This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the develo...This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the development of a plastic zone. Also this study developed a stress change and fracture development model of the underlying coal-rock mass. In addition, the stress and depth of fracture of any point in the floor were deduced with the application of Maple Calculation Software. The specific engineering parameters of the Pingdingshan No. 12 colliery were applied to determine the relationship between the depth of fracture in the floor and the mining height. The pressure-relief principle of the underlying coal-rock mass was analyzed while varying the mining height of the upper protective seam. The findings indicate that as the depth of fracture in the floor increases, the underlying coal-rock mass experiences a limited amount of pressure relief, and the pressure relief protection range becomes narrower.Additionally, the stress distribution evolves from a ‘‘U" shape into a ‘‘V" shape. A 2.0 m mining height of protective seam situates the outburst-prone seam, Ji_(15), within the effective pressure relief protection range. The fracture development and stress-relief ratio rises to 88%, ensuring the pressure-relief effect as well as economic benefits. The measurement data show that: after mining the upper protective seam, the gas pressure of Ji_(15) dropped from 1.78 to 0.35 MPa, demonstrating agreement between the engineering application and the theoretical calculation.展开更多
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyl...[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture.展开更多
The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural haza...The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural hazards such as landslides and mudslides.This study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow protection.Debris flow velocity and kinetic energy variations were studied through single-factor experiments.Suitable baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris flow.Subsequently,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of baffles.The research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their energy.When the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition area.Similarly,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition area.Through orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>h.When the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>h.The experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9.展开更多
[Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal do...[Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal dose(LD_(50))was determined by acute toxicity test with the toxic reaction and mortality of mice as indexes.Sixty Kunming mice were randomly divided into 6 groups:normal control group,model group(ConA-induced liver injury model),Jinchuan formula plum wine high,medium and low dose groups(1.0,0.5,0.25 g/kg)and silybin group(0.1 g/kg).The levels of ALT,AST,LDH in serum and TG,VLDL in liver were measured.After HE staining,the pathological changes of liver tissue in mice were observed,and the liver protective effect of Jinchuan formula plum wine extract was analyzed and evaluated.[Results]LD_(50)was 11.18 g/kg,and the 95%confidence limit of LD_(50)was 10.31-12.05 g/kg.The high-dose group of Jinchuan formula plum wine extract could significantly reduce the serum ALT and AST activities of ConA-induced liver injury mice(P<0.05).[Conclusions]Jinchuan formula plum wine extract is relatively safe,and also has a protective effect on liver injury.展开更多
Protected areas(PAs) have experienced explosive growth in Northwest China over the last three decades, but their effectiveness in representing regional ecological system diversity has not attracted considerable attent...Protected areas(PAs) have experienced explosive growth in Northwest China over the last three decades, but their effectiveness in representing regional ecological system diversity has not attracted considerable attention. Low effectiveness would exacerbate the conservation-development conflicts, particularly those that arise as a result of the Great Western Development Strategy(GWDS). Thus, an assessment of the effectiveness of the PA network has become quite important. We proposed natural vegetation communities to represent regional ecological system diversities, and proposed Global 200 Priority Ecoregions, Important Bird Areas, and ecosystem function regions to represent important conservation areas. To determine their effectiveness, we studied the extent to which ecological system diversities and important conservation areas are represented by the existing 96 PAs. Our results indicated that the total coverage of vegetation communities in PAs in Northwest China is not sufficiently comprehensive. As the PA system has expanded, the growth in the total area of the PAs has been greater than that of their vegetation community richness. While most of the important conservation areas are covered by PAs, some regions have not yet reached the 10% threshold; further, PAs are distributed unevenly and conservation gaps remain in the region. Therefore, these regions should receive more attention when planning new PAs. It is vital that more biodiversity datasets and assessment of ecosystem function regions are integrated in order to provide a basis for the government to formulate appropriate protection and development strategies.展开更多
The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.T...The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR.展开更多
Following is an interview by staff reporters of the Human Rights magazine with Zheng Silin, Chinese minister of labor and social security. The interview was meant in part to celebrate the tenth anniversary of the impl...Following is an interview by staff reporters of the Human Rights magazine with Zheng Silin, Chinese minister of labor and social security. The interview was meant in part to celebrate the tenth anniversary of the implementation of the Labor Law of the People's Republic of China that falls on January 1,2005. We are publishing this transcript with a view to providing our readers with information about how China has worked persistently to protect citizens' right to work and social security and the achievements it has made in this regard. We need to remind our readers of the fact that back in March 2004, the National People's Congress, China's highest legislature, approved a recommendation for revision of China's Constitution. In accordance with the recommendation, the Constitution had one more clause added: The state shall establish and improve a social security system commensurate to the level of the economic and social development.展开更多
Objective:The study was to explore the effect of evidence-based management in occupational protection for nurses who perform chemotherapy.Methods:40 chemotherapy nurses were selected,20 of them were included in the ex...Objective:The study was to explore the effect of evidence-based management in occupational protection for nurses who perform chemotherapy.Methods:40 chemotherapy nurses were selected,20 of them were included in the experimental group for evidence-based management,and the other 20 were included in the control group for routine management.Results:Compared with the control group,there were significantly fewer adverse nursing events in the experimental group,and P<0.05.Conclusion:The effect of evidence-based management in occupational protection of nurses who perform chemotherapy is significant.展开更多
The Chinese government will step up its efforts to stop the country’s wetlands from shrinking, said Ma Fu, Deputy Director of the State’s Forestry Administration, while announcing the newly drafted the Action Plan f...The Chinese government will step up its efforts to stop the country’s wetlands from shrinking, said Ma Fu, Deputy Director of the State’s Forestry Administration, while announcing the newly drafted the Action Plan for National Wetlands Conservation on November 8th in Beijing.展开更多
Reactive oxygen species(ROS)-induced oxidative damage is strongly associated with the pathogenesis of chronic diseases,and natural antioxidant peptides have good abilities of scavenging ROS.The antioxidant activity of...Reactive oxygen species(ROS)-induced oxidative damage is strongly associated with the pathogenesis of chronic diseases,and natural antioxidant peptides have good abilities of scavenging ROS.The antioxidant activity of peptide Lys-Ser-Pro-Leu-Tyr(KSPLY)derived from Hericium erinaceus remains unclear.In the present study,the antioxidant effect and mechanism of KSPLY on H_(2)O_(2)-induced oxidative damage in HepG2 cells were investigated.The results indicated that KSPLY exhibited the antioxidant capacity in H_(2)O_(2)-induced HepG2 cells by enhancing superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT)activities.In comparison with the H_(2)O_(2)-treated damage group,the apoptosis rate,ROS level,and malondialdehyde(MDA)content of HepG2 cells treated with KSPLY were significantly decreased.The H.erinaceus-derived peptide KSPLY pretreatment promoted the expression of detoxification and antioxidant enzymes via the Keap1/Nrf2 signal pathway,thereby inhibiting the generation of ROS and MDA.In conclusion,the H.erinaceus-derived peptide KSPLY effectively protected HepG2 cells against H_(2)O_(2)-induced oxidative damage,and it provided a theoretical basis for the further development of new natural antioxidants.展开更多
[Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose ...[Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose extract group(200 mg/kg),low-dose extract group(100 mg/kg)and positive control group(2 mg/kg colchicine),with 5 mice in each group.All groups except the blank group were given intraperitoneal injection of 20%CCl 4 olive oil solution(2 mL/kg),and the blank group was given the same dose of olive oil solution three times a week.After 4 weeks,each administration group was given the corresponding dose of drugs(10 mL/kg),and the blank group and model group were given the corresponding amount of normal saline for 2 weeks.After the last intragastric administration,fasting was required,but water was allowed,blood was taken from eyeballs,and upper serum was taken by static centrifugation.Serum AST,ALT,CRP,IL-6 and SOD levels were detected by the kit.[Results]Compared with the blank group,the serum AST and ALT levels in the model group were significantly increased;compared with the model group,the ethanol extract of sweet potato leaves could decrease the levels of ALT,AST,CRP,IL-6 and increase the level of SOD in serum.[Conclusions]The ethanol extract of sweet potato leaves had protective effect on the mice with liver injury induced by CCl_(4),and its mechanism may be to protect the liver by lowering enzymes,inhibiting inflammation and antioxidant stress.展开更多
Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion (I/R) injury and microRNAs (miRNAs) could act on various facets of cardiac function. However, the role of miRNA...Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion (I/R) injury and microRNAs (miRNAs) could act on various facets of cardiac function. However, the role of miRNAs in the cardioprotection by electroacupuncture pre-treatment on myocardial I/R injury remains unknown. The purpose of the study was to examine whether miR-214 was involved in cardio-protection by electroacupuncture. Methods Using rat myocardial I/R model, we examined the role of electroacupuncture pretreatment in myocardial I/R injury and analyzed the changes in the expression of miR-214. In addition, I/R was simulated in vitro by performing oxy-gen-glucose deprivation (OGD) on H9c2 cell cultures, and the effect of electroacupuncture pretreatment on I/R injury as well as expressional level of miR-214 were examined in vitro. Furthermore, the miR-214 mimic was transfected into OGD-treated H9c2 cells, we analyzed the cell apoptosis, lactate dehydrogenase (LDH) and creatine kinase (CK) activities, intracellular free Ca2+concentration ([Ca2+]i) as well as the relative protein levels of sodium/calcium exchanger 1(NCX1), BCL2-like 11 (BIM), calmodulin-dependent protein kinase IIδ(CaMKIIδ) and Cyclophilin D (CypD). Results The in vivo results revealed that compared with the I/R group, the electroacupuncture pretreatment group showed significant decreased myocardial infarct size, as well as the increased indices of the cardiac function, including heart rate, mean arterial pressure, left ventricular systolic pressure and maximal rate for left ventricular pressure rising and declining (±dp/dt max). In addition, electroacupuncture pretreatment could inhibit the elevation of LDH and CK activities induced by I/R injury. The quantitative PCR (qPCR) results demonstrated electroacupuncture pretreatment could provide cardioprotection against myocardial I/R injury in rats with miR-214 up-regulation. In the meanwhile, in vitro, electroacupuncture pretreatment protected H9c2 cells from OGD-induced injury. Trans-fection of miR-214 mimic showed protective effects on OGD-induced injury to H9c2 cells by reducing apoptosis, decreasing LDH and CK activities, rescuing the OGD-induced Ca2+and down-regulating elevated protein levels of NCX1, BIM, CaMKIIδand CypD. Conclusions Our findings firstly demonstrated that electroacupuncture pretreatment promotes the expression of miR-214 in myocardial I/R injury and miR-214 contributes to the protective effect of electroacupuncture on myocardial I/R injury.展开更多
AIM: To investigate the association between nutrient intakes and high incidence rate of gastric cancer among residents in Zhoushan Islands.METHODS: A frequency-matched design of case-control study was used during the ...AIM: To investigate the association between nutrient intakes and high incidence rate of gastric cancer among residents in Zhoushan Islands.METHODS: A frequency-matched design of case-control study was used during the survey on dietary factors and gastric cancer in Zhoushan Islands, China. A total of 103 cases of gastric cancer diagnosed in 2001 were included in the study and 133 controls were randomly selected from the residents in Zhoushan Islands. A food frequency questionnaire was specifically designed for the Chinese dietary pattern to collect information on dietary intake. A computerized database of the dietary and other relative information of each participant was completed. Total calories and 15 nutrients were calculated according to the food composition table and their adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by gender using unconditional logistic regression models.RESULTS: High intakes of protein, saturated fat, and cholesterol were observed with the increased risk of gastric cancer particularly among males (ORQ4 vsQ1 were 10.3, 3.24, 2.76 respectively). While carbohydrate was a significant high-risk nutrient (ORQ4 vsQ1 = 14.8; Pfor linear trend = 0.024) among females. Regardless of their gender, the cases reported significantly higher daily intake of sodium mainly from salts. As to the nutrients of vitamins A and C, an inversed association with the risk of GC was found. Baseline characteristics of participants were briefly described.CONCLUSION: The findings from this study confirm the role of diet-related exposure in the etiology of gastric cancer from the point of view of epidemiology. An increased risk of gastric cancer is associated with high intakes of protein, saturated fat, cholesterol and sodium,while consumption of polyunsaturated fat, vitamin A and ascorbic acid may have a protective effect against gastric cancer.展开更多
The seedling hydroponic culture experiment of kidney bean ( Phaseolus vulgaris ) and corn ( Zea mays ) was conducted to investigate the alleviation effect of lanthanum on Cd stress. It is found that growth is seri...The seedling hydroponic culture experiment of kidney bean ( Phaseolus vulgaris ) and corn ( Zea mays ) was conducted to investigate the alleviation effect of lanthanum on Cd stress. It is found that growth is seriously inhibited and metabolism is maladjusted in the two crops under 30 and 300 μmol·L^-1 Cd^2+ stress. Plant height, taproot length, leaf area, and fresh or dry weight of root, stem, and leaf are all obviously decreased. Further, chlorophyll content decreases, membrane permeability, malonydialdehyde (MDA) content, activities of catalase (CAT) and peroxidase (POD) increases under Cd stress, as compared with the control. The damage to these two crops becomes more conspicuous with the prolongation of Cd stress. It is suggested that lanthanum might help kidney bean and corn seedlings alleviate Cd stress by improving the photosynthetic capacity, reducing membrane permeability and MDA content, and maintaining the activities of CAT and POD of these two crops.展开更多
BACKGROUND: The majority of studies addressing spinal cord ischemia/reperfusion injury (SCIRI) have focused on drugs, proteins, cytokines, and various surgical techniques. A recent study reports that human umbilica...BACKGROUND: The majority of studies addressing spinal cord ischemia/reperfusion injury (SCIRI) have focused on drugs, proteins, cytokines, and various surgical techniques. A recent study reports that human umbilical cord mesenchymal stem cell (hUCMSC) transplantation achieves good therapeutic effects, but the mechanisms underlying nerve protection remain poorly understood. OBJECTIVE: To observe survival of transplanted hUCMSCs in SCIRI rat models and the influence on motor function in the hind limbs, to determine interleukin-8 expression and cellular apoptosis in spinal cord tissues, and to verify the hypothesis that hUCMSC transplantation exhibits protective effects on SCIRI. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Laboratory of the Department of Orthopedics in the First Affiliated Hospital of Soochow University, China between January 2007 and December 2008. MATERIALS: hUCMSCs were harvested from umbilical cord blood of healthy pregnant women after parturition in the Obstetrical Department of the First Affiliated Hospital of Soochow University, China. Rabbit anti-human BrdU monoclonal antibody was provided by DAKO, USA. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) Kit and enzyme-linked immunosorbent assay (ELISA) Kit were purchased by Wuhan Boster, China. METHODS: A total of 72 healthy, Wistar, adult rats were randomly assigned to three groups: sham-surgery, model, and transplantation, with 24 rats in each group. SCIRI was induced in the model and transplantation groups via the abdominal aorta block method. The infrarenal abdominal aorta was not blocked in the sham-surgery group. Prior to abdominal aorta occlusion, 0.2 03 mL bromodeoxyuridine (BrdU)-Iabeled hUCMSCs suspension (cell concentration 5 × 10 3/uL) was injected through the great saphenous vein of the hind limb, and an equal volume of physiological saline was administered to the model and sham-surgery groups. MAIN OUTCOME MEASURES: Pathological observation of rat spinal cord tissues was performed by hematoxylin-eosin staining at 6, 24, and 48 hours post-surgery. Immunohistochemistry was applied to determine hUCMSCs survival in the spinal cord. The amount of cellular apoptosis and interleukin-8 expression in spinal cord tissues was assayed utilizing the TUNEL and ELISA methods, respectively. Motor function in the hind limbs was evaluated according to Jacob's score. RESULTS: Numerous BrdU-positive cells were observed in spinal cord tissues from the transplantation group. The number of apoptotic cells and interleukin-8 levels significantly decreased in the transplantation group (P 〈 0.05), pathological injury was significantly ameliorated, and motor function scores significantly increased (P 〈 0.05) compared with the model group. CONCLUSION: Via vein transplantation, hUCMSCs were shown to reach and survive in the injury area. Results suggested that the transplanted hUCMSCs contributed to significantly improved pathological changes in the injured spinal cord, as well as motor function, following SCIRI. The protective mechanism correlated with inhibition of cellular apoptosis and reduced production of inflammatory mediators.展开更多
This study aims to observe the protective effects of ginsenoside Rbl on liver and lung in rats with septic shock and reveal its mechanism. Rats were randomly divided into three groups: sham, cecal ligation and punctu...This study aims to observe the protective effects of ginsenoside Rbl on liver and lung in rats with septic shock and reveal its mechanism. Rats were randomly divided into three groups: sham, cecal ligation and puncture (CLP), and CLP with ginsenoside Rb1. Then, the survival rate, arterial blood pressure, TLR4 mRNA, and TNF-α levels were determined. The liver and lung tissues were stained with hematoxylin-eosin (HE). The overall survival rate of the Rb1 group was significantly higher than that of the CLP group. Mean arterial blood pressure went down in both the CLP and Rb1 groups after CLP, and there was a significant difference both in the sham and Rb1 groups when compared with the CLP group. The Rb1 treatment group had markedly lower TLR4 mRNA expression and TNF-a levels than the CLP group. In the CLP group, pathology showed swelling, degeneration, necrosis, and neutrophii infiltration in the liver and alveolar epithelial cells. However, in the Rb1 group, there was mild degeneration and slight neutrophil infiltration, but no obvious necrosis. Rb1 may improve the survival rate, ameliorate arterial blood pressure, and protect the liver and lung in septic shock rats by downregulating the expression of TLR4 mRNA and inhibiting the production of TNF-α.展开更多
Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed pr...Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group (P〈0.01), while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.展开更多
The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (...The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (a) pyrene to nuclear DNA. Unscheduled DNA synthesis (UDS) induced by aflatoxin BI (10^(-7) mol.L-1) in freshly isolated rat hepatocytes was also inhibited by DDB (10^(-6)-10^(-3)mol.L-1). Oral administration of DDB at 200 mg.kg-1 once daily for 3 d induced a significant increase of liver cytosol glutathione-S-transferase and microsomal UDPG-transferase activity in mice. These results indicate that DDB is able to directly or indirectly antagonize certain carcinogen-induced DNA damages.展开更多
OBJECTIVE To investigate the effect of quercetin on primary cultured newborn rat cortex neuron cell which is estrogen depletion,and discuss the possible mechanism,to provide new ideas and strategies for developing a d...OBJECTIVE To investigate the effect of quercetin on primary cultured newborn rat cortex neuron cell which is estrogen depletion,and discuss the possible mechanism,to provide new ideas and strategies for developing a drug of neurodegenerative disease.METHODS Rat cortex neurons were isolated from one day old Sprague Dawley rats and treated with estrogen,quercetin and estrogen receptor antagonists(ICI182,780).Cell viability was determined by MTT assay,neurite outgrowth was measured by fluorescent microsope and estrogen receptors were determine by Western blot.RESULTS Quercetin functions like estrogen to increase cortex neuronal cell viability,the Que(50,100μmol·L^(-1))group compared with the control group could significantly improve the activity of the cortical neurons(P<0.05).It can also increase neurite out growth,the Que(50,100μmol·L^(-1))group significantly promoted the formation of synapse,most of the neurons were full,and the synapses of neurons became thick,growth,and connect to a dense neural network.And in the Western blot experiments,Que(50,100μmol·L^(-1))group could obviously increase the expression of estrogen receptor alpha protein,in addition,the neural protective effect of quercetin can be inhibited by ICI182,780.CONCLUSION Quercetin like estrogen can protected cortex neuronal and the effect of quercetin on cortex neuronal cells was mediated by estrogen receptor alpha.展开更多
Objective To study effects of saturated hydrogen saline in preventing noise-induced hearing loss. Methods Fifteen guinea pigs were randomly divided into 3 groups (5 each), group one was for control, group two was tr...Objective To study effects of saturated hydrogen saline in preventing noise-induced hearing loss. Methods Fifteen guinea pigs were randomly divided into 3 groups (5 each), group one was for control, group two was treated with normal saline and group three was treated with saturated hydrogen saline, which was given intraperitoneally at 1 hour before noise exposure at 1 ml/100 g. One hundred rounds of impulse noise ( 157 dB SPL peak) were delivered as noise exposure. Immediately after exposure to impulse noise and on Days 1, 2, 4 and 8 following exposure, auditory brainstem response (ABR) thresholds were measured. Outer hair cell morphological changes and sueeinate dehydrogenase (SDH) activity were examined on Day 8 post-exposure. Results Immediately after noise exposure, ABR thresholds in saturated hydrogen saline treated animals were lower than the non-treated animals (P 〈 0.05 ). Microscopy showed little SDH staining, cell swelling and irregular cell arrangement in the non-treated or normal saline treated animals. Whereas in the saturated hydrogen saline treated animals, there was deep SDH staining with significantly reduced cell loss and more regular cellular arrangement compared to the other two groups. The surviving cells counts was 45.17 ±12.15 for non-treated animals, 44.50 ±10.02 for normal saline treated animals and,116.50±2.38 for animals treated with saturated hydrogen saline. While the count was similar between non-treated and normal saline treated animals, it was significantly higher in saturated sions Intraperitoneal injection of saturated hydrogen saline damage. hydrogen saline treated animals (P 〈 0.05). Concluappears to protect the cochlea against noise-induced damage.展开更多
基金supported by the Foundation for Distinguished professor of Jiangsu Provincethe Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.51421003)
文摘This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the development of a plastic zone. Also this study developed a stress change and fracture development model of the underlying coal-rock mass. In addition, the stress and depth of fracture of any point in the floor were deduced with the application of Maple Calculation Software. The specific engineering parameters of the Pingdingshan No. 12 colliery were applied to determine the relationship between the depth of fracture in the floor and the mining height. The pressure-relief principle of the underlying coal-rock mass was analyzed while varying the mining height of the upper protective seam. The findings indicate that as the depth of fracture in the floor increases, the underlying coal-rock mass experiences a limited amount of pressure relief, and the pressure relief protection range becomes narrower.Additionally, the stress distribution evolves from a ‘‘U" shape into a ‘‘V" shape. A 2.0 m mining height of protective seam situates the outburst-prone seam, Ji_(15), within the effective pressure relief protection range. The fracture development and stress-relief ratio rises to 88%, ensuring the pressure-relief effect as well as economic benefits. The measurement data show that: after mining the upper protective seam, the gas pressure of Ji_(15) dropped from 1.78 to 0.35 MPa, demonstrating agreement between the engineering application and the theoretical calculation.
基金Supported by National Key Technology R&D Program(2006BAD05B06-04)Kunming Science and Technology Program(08S010201)~~
文摘[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture.
基金provided by the National Natural Science Foundation of China(Grant No.41977233)the key projects of the Science and Technology Department of Sichuan Province(Grant No.2020YJ0360)+1 种基金Sichuan Education and Teaching Reform project(Grant No.JG2021-1069)the opening project of Sichuan province university key Laboratory(Grant No.SC_FQWLY-2020-Z-02)。
文摘The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural hazards such as landslides and mudslides.This study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow protection.Debris flow velocity and kinetic energy variations were studied through single-factor experiments.Suitable baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris flow.Subsequently,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of baffles.The research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their energy.When the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition area.Similarly,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition area.Through orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>h.When the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>h.The experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9.
文摘[Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal dose(LD_(50))was determined by acute toxicity test with the toxic reaction and mortality of mice as indexes.Sixty Kunming mice were randomly divided into 6 groups:normal control group,model group(ConA-induced liver injury model),Jinchuan formula plum wine high,medium and low dose groups(1.0,0.5,0.25 g/kg)and silybin group(0.1 g/kg).The levels of ALT,AST,LDH in serum and TG,VLDL in liver were measured.After HE staining,the pathological changes of liver tissue in mice were observed,and the liver protective effect of Jinchuan formula plum wine extract was analyzed and evaluated.[Results]LD_(50)was 11.18 g/kg,and the 95%confidence limit of LD_(50)was 10.31-12.05 g/kg.The high-dose group of Jinchuan formula plum wine extract could significantly reduce the serum ALT and AST activities of ConA-induced liver injury mice(P<0.05).[Conclusions]Jinchuan formula plum wine extract is relatively safe,and also has a protective effect on liver injury.
基金Under the auspices of National Science&Technology Pillar Program During the Twelfth Five-year Plan Period(No.2011BAC09B08)
文摘Protected areas(PAs) have experienced explosive growth in Northwest China over the last three decades, but their effectiveness in representing regional ecological system diversity has not attracted considerable attention. Low effectiveness would exacerbate the conservation-development conflicts, particularly those that arise as a result of the Great Western Development Strategy(GWDS). Thus, an assessment of the effectiveness of the PA network has become quite important. We proposed natural vegetation communities to represent regional ecological system diversities, and proposed Global 200 Priority Ecoregions, Important Bird Areas, and ecosystem function regions to represent important conservation areas. To determine their effectiveness, we studied the extent to which ecological system diversities and important conservation areas are represented by the existing 96 PAs. Our results indicated that the total coverage of vegetation communities in PAs in Northwest China is not sufficiently comprehensive. As the PA system has expanded, the growth in the total area of the PAs has been greater than that of their vegetation community richness. While most of the important conservation areas are covered by PAs, some regions have not yet reached the 10% threshold; further, PAs are distributed unevenly and conservation gaps remain in the region. Therefore, these regions should receive more attention when planning new PAs. It is vital that more biodiversity datasets and assessment of ecosystem function regions are integrated in order to provide a basis for the government to formulate appropriate protection and development strategies.
基金sponsored by the National Social Science Foundation of China"Research on the Status,Efficiencies and the Policy on the National Significant Seismic Monitoring and Protection Regions"(11&ZD054)
文摘The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR.
文摘Following is an interview by staff reporters of the Human Rights magazine with Zheng Silin, Chinese minister of labor and social security. The interview was meant in part to celebrate the tenth anniversary of the implementation of the Labor Law of the People's Republic of China that falls on January 1,2005. We are publishing this transcript with a view to providing our readers with information about how China has worked persistently to protect citizens' right to work and social security and the achievements it has made in this regard. We need to remind our readers of the fact that back in March 2004, the National People's Congress, China's highest legislature, approved a recommendation for revision of China's Constitution. In accordance with the recommendation, the Constitution had one more clause added: The state shall establish and improve a social security system commensurate to the level of the economic and social development.
文摘Objective:The study was to explore the effect of evidence-based management in occupational protection for nurses who perform chemotherapy.Methods:40 chemotherapy nurses were selected,20 of them were included in the experimental group for evidence-based management,and the other 20 were included in the control group for routine management.Results:Compared with the control group,there were significantly fewer adverse nursing events in the experimental group,and P<0.05.Conclusion:The effect of evidence-based management in occupational protection of nurses who perform chemotherapy is significant.
文摘The Chinese government will step up its efforts to stop the country’s wetlands from shrinking, said Ma Fu, Deputy Director of the State’s Forestry Administration, while announcing the newly drafted the Action Plan for National Wetlands Conservation on November 8th in Beijing.
基金supported by the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(20KJB550016)the National Natural Science Foundation of China(32101944)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Reactive oxygen species(ROS)-induced oxidative damage is strongly associated with the pathogenesis of chronic diseases,and natural antioxidant peptides have good abilities of scavenging ROS.The antioxidant activity of peptide Lys-Ser-Pro-Leu-Tyr(KSPLY)derived from Hericium erinaceus remains unclear.In the present study,the antioxidant effect and mechanism of KSPLY on H_(2)O_(2)-induced oxidative damage in HepG2 cells were investigated.The results indicated that KSPLY exhibited the antioxidant capacity in H_(2)O_(2)-induced HepG2 cells by enhancing superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT)activities.In comparison with the H_(2)O_(2)-treated damage group,the apoptosis rate,ROS level,and malondialdehyde(MDA)content of HepG2 cells treated with KSPLY were significantly decreased.The H.erinaceus-derived peptide KSPLY pretreatment promoted the expression of detoxification and antioxidant enzymes via the Keap1/Nrf2 signal pathway,thereby inhibiting the generation of ROS and MDA.In conclusion,the H.erinaceus-derived peptide KSPLY effectively protected HepG2 cells against H_(2)O_(2)-induced oxidative damage,and it provided a theoretical basis for the further development of new natural antioxidants.
基金Supported by National College Students Innovation and Entrepreneurship Training Program(202110599016)Guangxi Key R&D Project(GuiKeAB 18221095).
文摘[Objectives]To investigate the protective effect of ethanol extract from sweet potato leaves on liver injury induced by CCl_(4)in mice.[Methods]25 ICR mice were randomly divided into blank group,model group,high-dose extract group(200 mg/kg),low-dose extract group(100 mg/kg)and positive control group(2 mg/kg colchicine),with 5 mice in each group.All groups except the blank group were given intraperitoneal injection of 20%CCl 4 olive oil solution(2 mL/kg),and the blank group was given the same dose of olive oil solution three times a week.After 4 weeks,each administration group was given the corresponding dose of drugs(10 mL/kg),and the blank group and model group were given the corresponding amount of normal saline for 2 weeks.After the last intragastric administration,fasting was required,but water was allowed,blood was taken from eyeballs,and upper serum was taken by static centrifugation.Serum AST,ALT,CRP,IL-6 and SOD levels were detected by the kit.[Results]Compared with the blank group,the serum AST and ALT levels in the model group were significantly increased;compared with the model group,the ethanol extract of sweet potato leaves could decrease the levels of ALT,AST,CRP,IL-6 and increase the level of SOD in serum.[Conclusions]The ethanol extract of sweet potato leaves had protective effect on the mice with liver injury induced by CCl_(4),and its mechanism may be to protect the liver by lowering enzymes,inhibiting inflammation and antioxidant stress.
基金This study was supported by a grant from the Hainan Provincial Nature Science Foundation
文摘Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion (I/R) injury and microRNAs (miRNAs) could act on various facets of cardiac function. However, the role of miRNAs in the cardioprotection by electroacupuncture pre-treatment on myocardial I/R injury remains unknown. The purpose of the study was to examine whether miR-214 was involved in cardio-protection by electroacupuncture. Methods Using rat myocardial I/R model, we examined the role of electroacupuncture pretreatment in myocardial I/R injury and analyzed the changes in the expression of miR-214. In addition, I/R was simulated in vitro by performing oxy-gen-glucose deprivation (OGD) on H9c2 cell cultures, and the effect of electroacupuncture pretreatment on I/R injury as well as expressional level of miR-214 were examined in vitro. Furthermore, the miR-214 mimic was transfected into OGD-treated H9c2 cells, we analyzed the cell apoptosis, lactate dehydrogenase (LDH) and creatine kinase (CK) activities, intracellular free Ca2+concentration ([Ca2+]i) as well as the relative protein levels of sodium/calcium exchanger 1(NCX1), BCL2-like 11 (BIM), calmodulin-dependent protein kinase IIδ(CaMKIIδ) and Cyclophilin D (CypD). Results The in vivo results revealed that compared with the I/R group, the electroacupuncture pretreatment group showed significant decreased myocardial infarct size, as well as the increased indices of the cardiac function, including heart rate, mean arterial pressure, left ventricular systolic pressure and maximal rate for left ventricular pressure rising and declining (±dp/dt max). In addition, electroacupuncture pretreatment could inhibit the elevation of LDH and CK activities induced by I/R injury. The quantitative PCR (qPCR) results demonstrated electroacupuncture pretreatment could provide cardioprotection against myocardial I/R injury in rats with miR-214 up-regulation. In the meanwhile, in vitro, electroacupuncture pretreatment protected H9c2 cells from OGD-induced injury. Trans-fection of miR-214 mimic showed protective effects on OGD-induced injury to H9c2 cells by reducing apoptosis, decreasing LDH and CK activities, rescuing the OGD-induced Ca2+and down-regulating elevated protein levels of NCX1, BIM, CaMKIIδand CypD. Conclusions Our findings firstly demonstrated that electroacupuncture pretreatment promotes the expression of miR-214 in myocardial I/R injury and miR-214 contributes to the protective effect of electroacupuncture on myocardial I/R injury.
基金Supported by the Foundation of Ministry of Public Health of China, No. WKZ-2001-1-17
文摘AIM: To investigate the association between nutrient intakes and high incidence rate of gastric cancer among residents in Zhoushan Islands.METHODS: A frequency-matched design of case-control study was used during the survey on dietary factors and gastric cancer in Zhoushan Islands, China. A total of 103 cases of gastric cancer diagnosed in 2001 were included in the study and 133 controls were randomly selected from the residents in Zhoushan Islands. A food frequency questionnaire was specifically designed for the Chinese dietary pattern to collect information on dietary intake. A computerized database of the dietary and other relative information of each participant was completed. Total calories and 15 nutrients were calculated according to the food composition table and their adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by gender using unconditional logistic regression models.RESULTS: High intakes of protein, saturated fat, and cholesterol were observed with the increased risk of gastric cancer particularly among males (ORQ4 vsQ1 were 10.3, 3.24, 2.76 respectively). While carbohydrate was a significant high-risk nutrient (ORQ4 vsQ1 = 14.8; Pfor linear trend = 0.024) among females. Regardless of their gender, the cases reported significantly higher daily intake of sodium mainly from salts. As to the nutrients of vitamins A and C, an inversed association with the risk of GC was found. Baseline characteristics of participants were briefly described.CONCLUSION: The findings from this study confirm the role of diet-related exposure in the etiology of gastric cancer from the point of view of epidemiology. An increased risk of gastric cancer is associated with high intakes of protein, saturated fat, cholesterol and sodium,while consumption of polyunsaturated fat, vitamin A and ascorbic acid may have a protective effect against gastric cancer.
文摘The seedling hydroponic culture experiment of kidney bean ( Phaseolus vulgaris ) and corn ( Zea mays ) was conducted to investigate the alleviation effect of lanthanum on Cd stress. It is found that growth is seriously inhibited and metabolism is maladjusted in the two crops under 30 and 300 μmol·L^-1 Cd^2+ stress. Plant height, taproot length, leaf area, and fresh or dry weight of root, stem, and leaf are all obviously decreased. Further, chlorophyll content decreases, membrane permeability, malonydialdehyde (MDA) content, activities of catalase (CAT) and peroxidase (POD) increases under Cd stress, as compared with the control. The damage to these two crops becomes more conspicuous with the prolongation of Cd stress. It is suggested that lanthanum might help kidney bean and corn seedlings alleviate Cd stress by improving the photosynthetic capacity, reducing membrane permeability and MDA content, and maintaining the activities of CAT and POD of these two crops.
文摘BACKGROUND: The majority of studies addressing spinal cord ischemia/reperfusion injury (SCIRI) have focused on drugs, proteins, cytokines, and various surgical techniques. A recent study reports that human umbilical cord mesenchymal stem cell (hUCMSC) transplantation achieves good therapeutic effects, but the mechanisms underlying nerve protection remain poorly understood. OBJECTIVE: To observe survival of transplanted hUCMSCs in SCIRI rat models and the influence on motor function in the hind limbs, to determine interleukin-8 expression and cellular apoptosis in spinal cord tissues, and to verify the hypothesis that hUCMSC transplantation exhibits protective effects on SCIRI. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Laboratory of the Department of Orthopedics in the First Affiliated Hospital of Soochow University, China between January 2007 and December 2008. MATERIALS: hUCMSCs were harvested from umbilical cord blood of healthy pregnant women after parturition in the Obstetrical Department of the First Affiliated Hospital of Soochow University, China. Rabbit anti-human BrdU monoclonal antibody was provided by DAKO, USA. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) Kit and enzyme-linked immunosorbent assay (ELISA) Kit were purchased by Wuhan Boster, China. METHODS: A total of 72 healthy, Wistar, adult rats were randomly assigned to three groups: sham-surgery, model, and transplantation, with 24 rats in each group. SCIRI was induced in the model and transplantation groups via the abdominal aorta block method. The infrarenal abdominal aorta was not blocked in the sham-surgery group. Prior to abdominal aorta occlusion, 0.2 03 mL bromodeoxyuridine (BrdU)-Iabeled hUCMSCs suspension (cell concentration 5 × 10 3/uL) was injected through the great saphenous vein of the hind limb, and an equal volume of physiological saline was administered to the model and sham-surgery groups. MAIN OUTCOME MEASURES: Pathological observation of rat spinal cord tissues was performed by hematoxylin-eosin staining at 6, 24, and 48 hours post-surgery. Immunohistochemistry was applied to determine hUCMSCs survival in the spinal cord. The amount of cellular apoptosis and interleukin-8 expression in spinal cord tissues was assayed utilizing the TUNEL and ELISA methods, respectively. Motor function in the hind limbs was evaluated according to Jacob's score. RESULTS: Numerous BrdU-positive cells were observed in spinal cord tissues from the transplantation group. The number of apoptotic cells and interleukin-8 levels significantly decreased in the transplantation group (P 〈 0.05), pathological injury was significantly ameliorated, and motor function scores significantly increased (P 〈 0.05) compared with the model group. CONCLUSION: Via vein transplantation, hUCMSCs were shown to reach and survive in the injury area. Results suggested that the transplanted hUCMSCs contributed to significantly improved pathological changes in the injured spinal cord, as well as motor function, following SCIRI. The protective mechanism correlated with inhibition of cellular apoptosis and reduced production of inflammatory mediators.
基金supported by the Major Invite Tender Project of Health Department of Jiangxi Province(No.20104005)the Major Project of the Department of Education of Jiangxi Province(No.GJJ12003)the 13th’Challenge Cup’of Extracurricular academic and scientific works of Nanchang University
文摘This study aims to observe the protective effects of ginsenoside Rbl on liver and lung in rats with septic shock and reveal its mechanism. Rats were randomly divided into three groups: sham, cecal ligation and puncture (CLP), and CLP with ginsenoside Rb1. Then, the survival rate, arterial blood pressure, TLR4 mRNA, and TNF-α levels were determined. The liver and lung tissues were stained with hematoxylin-eosin (HE). The overall survival rate of the Rb1 group was significantly higher than that of the CLP group. Mean arterial blood pressure went down in both the CLP and Rb1 groups after CLP, and there was a significant difference both in the sham and Rb1 groups when compared with the CLP group. The Rb1 treatment group had markedly lower TLR4 mRNA expression and TNF-a levels than the CLP group. In the CLP group, pathology showed swelling, degeneration, necrosis, and neutrophii infiltration in the liver and alveolar epithelial cells. However, in the Rb1 group, there was mild degeneration and slight neutrophil infiltration, but no obvious necrosis. Rb1 may improve the survival rate, ameliorate arterial blood pressure, and protect the liver and lung in septic shock rats by downregulating the expression of TLR4 mRNA and inhibiting the production of TNF-α.
基金supported by Key Program of National Natural Science Foundation of China(U1432248)National Natural Science Foundation of China(11175222,11305226)
文摘Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group (P〈0.01), while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.
文摘The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (a) pyrene to nuclear DNA. Unscheduled DNA synthesis (UDS) induced by aflatoxin BI (10^(-7) mol.L-1) in freshly isolated rat hepatocytes was also inhibited by DDB (10^(-6)-10^(-3)mol.L-1). Oral administration of DDB at 200 mg.kg-1 once daily for 3 d induced a significant increase of liver cytosol glutathione-S-transferase and microsomal UDPG-transferase activity in mice. These results indicate that DDB is able to directly or indirectly antagonize certain carcinogen-induced DNA damages.
基金supported by Science and Technology Research Project of Hebei Higher School,Hebei Education Department(ZD2015131)Natural Science Foundation of Hebei Province(H2012405016)
文摘OBJECTIVE To investigate the effect of quercetin on primary cultured newborn rat cortex neuron cell which is estrogen depletion,and discuss the possible mechanism,to provide new ideas and strategies for developing a drug of neurodegenerative disease.METHODS Rat cortex neurons were isolated from one day old Sprague Dawley rats and treated with estrogen,quercetin and estrogen receptor antagonists(ICI182,780).Cell viability was determined by MTT assay,neurite outgrowth was measured by fluorescent microsope and estrogen receptors were determine by Western blot.RESULTS Quercetin functions like estrogen to increase cortex neuronal cell viability,the Que(50,100μmol·L^(-1))group compared with the control group could significantly improve the activity of the cortical neurons(P<0.05).It can also increase neurite out growth,the Que(50,100μmol·L^(-1))group significantly promoted the formation of synapse,most of the neurons were full,and the synapses of neurons became thick,growth,and connect to a dense neural network.And in the Western blot experiments,Que(50,100μmol·L^(-1))group could obviously increase the expression of estrogen receptor alpha protein,in addition,the neural protective effect of quercetin can be inhibited by ICI182,780.CONCLUSION Quercetin like estrogen can protected cortex neuronal and the effect of quercetin on cortex neuronal cells was mediated by estrogen receptor alpha.
基金Supported by NFSC grant(30600700,30772413)Chinese PLA 12th five medical research grant
文摘Objective To study effects of saturated hydrogen saline in preventing noise-induced hearing loss. Methods Fifteen guinea pigs were randomly divided into 3 groups (5 each), group one was for control, group two was treated with normal saline and group three was treated with saturated hydrogen saline, which was given intraperitoneally at 1 hour before noise exposure at 1 ml/100 g. One hundred rounds of impulse noise ( 157 dB SPL peak) were delivered as noise exposure. Immediately after exposure to impulse noise and on Days 1, 2, 4 and 8 following exposure, auditory brainstem response (ABR) thresholds were measured. Outer hair cell morphological changes and sueeinate dehydrogenase (SDH) activity were examined on Day 8 post-exposure. Results Immediately after noise exposure, ABR thresholds in saturated hydrogen saline treated animals were lower than the non-treated animals (P 〈 0.05 ). Microscopy showed little SDH staining, cell swelling and irregular cell arrangement in the non-treated or normal saline treated animals. Whereas in the saturated hydrogen saline treated animals, there was deep SDH staining with significantly reduced cell loss and more regular cellular arrangement compared to the other two groups. The surviving cells counts was 45.17 ±12.15 for non-treated animals, 44.50 ±10.02 for normal saline treated animals and,116.50±2.38 for animals treated with saturated hydrogen saline. While the count was similar between non-treated and normal saline treated animals, it was significantly higher in saturated sions Intraperitoneal injection of saturated hydrogen saline damage. hydrogen saline treated animals (P 〈 0.05). Concluappears to protect the cochlea against noise-induced damage.