According to the characteristics of circular agricultural mode focusing on pig farming and by dint of system dynamics mode-based analysis techniques to analyze the characteristics,the operation force for the recycling...According to the characteristics of circular agricultural mode focusing on pig farming and by dint of system dynamics mode-based analysis techniques to analyze the characteristics,the operation force for the recycling agricultural system focusing on pig farming was put forward.展开更多
[Objective] The aim was to investigate the effects of Primo MAXX growth regulator on growth of Bermuda grass,explore appropriate application concentration of Primo MAXX on Bermuda grass,and provide basis for the appli...[Objective] The aim was to investigate the effects of Primo MAXX growth regulator on growth of Bermuda grass,explore appropriate application concentration of Primo MAXX on Bermuda grass,and provide basis for the application of Primo MAXX in Bermuda meadow.[Method]The height,leaf colour and the aerial part's fresh weight of Bermuda grass treated with different concentrations were researched using single factor random block test.[Result]Primo MAXX application effectively reduced the height in all treatment without significant difference;appropriate application of Primo MAXX can enrich the color;and 35 days after application,Bermuda grass roots were become thicker.[Conclusion]The application of Primo MAXX with effective dose of 150-300 g/hm2 on Bermuda grass in southern China is more appropriate.展开更多
AIM: To study the inhibitory effect of baculovirus- mediated normal epithelial cell specific-1 (NES1) gene therapy on gastric cancer (GC) in vitro and in vivo. METHODS: We first constructed recombinant baculovirus vec...AIM: To study the inhibitory effect of baculovirus- mediated normal epithelial cell specific-1 (NES1) gene therapy on gastric cancer (GC) in vitro and in vivo. METHODS: We first constructed recombinant baculovirus vectors and then transfected them into gastric cancer cells (SGC-7901). Efficiency of the baculovirus for gene transfer into SGC-7901 cells and cell growth curves were detected by fluorescence microscopy, Western blot and 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in vitro, respectively. The therapeutic effect of this gene therapy on GC was confirmed in xenografted nude mice. Tumor growth was determined by tumor volume, and expression of NES1 in tumor was analyzed by immunohistochemistry. RESULTS: Baculovirus vectors were successfully transfected into SGC-7901 cells. SGC-7901 cells transfected with the NES1 gene inhibited cell growth. In the Bac-NES1 treated group, tumor growth was significantly reduced with a high level of NES1 expression CONCLUSION: Baculovirus-mediated NES1 gene can be used in gene therapy for GC.展开更多
Via the valuable opportunity of the Three Gorges Reservoir (TGR) 135-m filling in June 2003, the Yangtze discharge and suspended sediment concentration (SSC) entering the estuary during the period from 15 May to 15 Ju...Via the valuable opportunity of the Three Gorges Reservoir (TGR) 135-m filling in June 2003, the Yangtze discharge and suspended sediment concentration (SSC) entering the estuary during the period from 15 May to 15 July 2003 were analyzed to examine the instant effects of the filling on them. The Yangtze discharge and SSC entering the estuary in the periods before, during and after the filling clearly indicated three phases: 1) the pre-storage phase characterized by natural conditions, in which the SSC increased with increasing water discharge; 2) the storage phase, during which the SSC decreased dramatically with decreasing water discharge; and 3) the post-storage phase, during which both the SSC and water discharge remained at relatively low levels first until the end of June, then the SSC increased gradually with increasing water discharge. It seems that the times for the instant effects of the decreasing discharge downstream from the upper Yangtze on the Yangtze discharge and SSC entering the estuary due to the TGR 135-m filling to take place were about 5 d and 1 d respectively, while both were about 18 d for those of the increasing discharge. This probably reflects the buffering and resultantly hysteresis of the 1800-km stretch from the upper Yangtze to the estuary. The results are helpful for scientific and hydrological investigation of the Yangtze mainstream downstream from the TGR Dam and of the estuarine and adjacent coastal waters.展开更多
AIM: To investigate the effect of serum derived from rats treated with electroacupuncture at stomach meridian acupoints on the expression of epidermal growth factor receptor (EGFR) gene in gastric mucosal cells. METHO...AIM: To investigate the effect of serum derived from rats treated with electroacupuncture at stomach meridian acupoints on the expression of epidermal growth factor receptor (EGFR) gene in gastric mucosal cells. METHODS: The stress-induced gastric mucosal injury in rat model was established by water-immersion and restrained stress methods. 52 rats were randomly divided into: normal group (n = 8), model group (n = 8), model serum group (n = 12), stomach serum group (n = 12), and gallbladder serum group (n = 12). The gastric mucosal cells were separated by pronase-EDTA digestion method and incubated with serum. The EGFR gene expression in gastric mucosal cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: Compared with normal group (0.6860 ± 0.0594), the serum derived from rats of the stomach group (1.2272 ± 0.0813, P = 0.00 < 0.01) and gallbladder group (0.9640 ± 0.0387, P = 0.00 < 0.01) had a tendency to enhance the EGFR gene expression in gastric mucosal cells. Such tendency existed in the model group (0.7104 ± 0.0457) but with no signifi cant difference (P = 0.495 > 0.05) and in model serum group (0.8516 ± 0.0409) with an extremely obvious difference (P = 0.001 < 0.01). Furthermore, the EGFR gene expression in stomach serum group was significantly higher than that in gallbladder serum group (P = 0.00 < 0.01). CONCLUSION: The present study shows that serumderived from rats treated with electroacupuncture at stomach meridian acupoints can distinctly increase the EGFR gene expression of gastric mucosal cells. Therefore, there is certain meridian specificity in the serum, which could provide a proof for the TCM theory “particular relation between meridian and internal organ”.展开更多
AIM: To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma (HCC). METHODS: Erlotinib-induced alterations in gene expression were evaluated using cDNA array technol...AIM: To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma (HCC). METHODS: Erlotinib-induced alterations in gene expression were evaluated using cDNA array technology; changes in protein expression and/or protein activation due to erlotinib treatment as well as IGF-1-induced EGFR transactivation were investigated using Western blotting. RESULTS: Erlotinib treatment inhibited the mitogen activated protein (MAP)-kinase pathway and signal transducer of activation and transcription (STAT)- mediated signaling which led to an altered expression of apoptosis and cell cycle regulating genes as demonstrated by cDNA array technology. Overexpression of proapoptotic factors like caspases and gadds associated with a down-regulation of antiapoptotic factors like Bcl-2, Bcl-XL or jun D accounted for erlotinib's potency to induce apoptosis. Downregulation of cell cycle regulators promoting the G1/S-transition and overexpression of cyclin-dependent kinase inhibitors and gadds contributed to the induction of a G1/G0-arrest in response to erlotinib. Furthermore, we displayed the transactivation of EGFR-mediated signaling by the IGF-1-receptor and showed erlotinib's inhibitory effects on the receptor-receptor cross talk. CONCLUSION: Our study sheds light on the understanding of the mechanisms of action of EGFR-TK- inhibition in HCC-cells and thus might facilitate the design of combination therapies that act additively or synergistically. Moreover, our data on the pathways responding to erlotinib treatment could be helpful in predicting the responsiveness of tumors to EGFR-TKIs in the future.展开更多
AIM: To investigate the expression of cyclooxygenase-2 (COX-2) and epithelial growth factor receptor (EGFR) throughout the progression of Barrett's esophagus (BE). METHODS: COX-2 and EGFR protein expressions ...AIM: To investigate the expression of cyclooxygenase-2 (COX-2) and epithelial growth factor receptor (EGFR) throughout the progression of Barrett's esophagus (BE). METHODS: COX-2 and EGFR protein expressions were detected by using immunohistochemical method. A detailed cytomorphological changes were determined. Areas of COX-2 and EGFR expression were quantified by using computer Imaging System. RESULTS: The expressions of both COX-2 and EGFR increased along with the progression from BE to esophagus adenocarcinoma (EAC). A positive correlation was found between COX-2 expression and EGFR expression. CONCLUSION: COX-2 and EGFR may be cooperative in the stepwise progression from BE to EAC, thereby leading to carcinogenesis.展开更多
Subsurface flow is a prominent runoff process in sloping lands of purple soil in the upper Yangtze River basin.However,it remains difficult to identify and quantify.In this study,in situ runoff experimental plots were...Subsurface flow is a prominent runoff process in sloping lands of purple soil in the upper Yangtze River basin.However,it remains difficult to identify and quantify.In this study,in situ runoff experimental plots were used to measure soil moisture dynamics using an array of time domain reflectometry(TDR) together with overland flow and subsurface flow using isolated collecting troughs.Frequency of preferential flow during rainfall events and the controls of subsurface flow processes were investigated through combined analysis of soil properties,topography,rainfall intensity,initial wetness,and tillage.Results showed that subsurface flow was ubiquitous in purple soil profiles due to welldeveloped macropores,especially in surface soils while frequency of preferential flow occurrence was very low(only 2 cases in plot C) during all 22 rainfall events.Dry antecedent moisture conditions promoted the occurrence of preferential flow.However,consecutive real-time monitoring of soil moisture at different depths and various slope positions implied the possible occurrence of multiple subsurface lateral flows during intensive storms.Rainfall intensity,tillage operation,and soil properties were recognized as main controls of subsurface flow in the study area,which allows the optimization of management practices for alleviating adverse environmental effects of subsurface flow in the region.展开更多
137 Cs is an artificial radionuclide with a half-life of 30.2 years,which was released into the environment as a byproduct of atmospheric testing of nuclear weapons during the period of 1950s to 1970s with a peak depo...137 Cs is an artificial radionuclide with a half-life of 30.2 years,which was released into the environment as a byproduct of atmospheric testing of nuclear weapons during the period of 1950s to 1970s with a peak deposition in 1963.137 Cs fallout was strongly and rapidly adsorbed by soil particles when it deposited on the ground mostly with precipitation.Its following movements will associate with the adsorbed particles.137 Cs tracing technique has been widely used in soil erosion and sedimentation studies since 1980s.This paper introduces the basis of the technique and shows several case studies of assessment of soil erosion rates,investigation of sediment sources and dating of reservoir deposits by using the technique in the Loess Plateau and the Upper Yangtze River Basin.展开更多
This paper synthesized the principal land denudation processes and their role in determining riverine suspended sediment yields(SSY) in two typical geographical environments of the Upper Yangtze River Basin in China a...This paper synthesized the principal land denudation processes and their role in determining riverine suspended sediment yields(SSY) in two typical geographical environments of the Upper Yangtze River Basin in China and the Volga River Basin in Eastern Europe. In the Upper Yangtze River Basin, natural factors including topography, climate,lithology and tectonic activity are responsible for the spatial variation in the magnitude of denudation rates.Human disturbances have contributed to the temporal changes of soil erosion and fluvial SSY during the past decades. On one hand, land use change caused by deforestation and land reclamation has played an important role in the acceleration of sediment production from the central hilly area and lower Jinsha catchment; On the other hand, diverse soil conservation practices(e.g., reforestation,terracing) have contributed to a reduction of soil erosion and sediment production since the late 1980 s.It was difficult to explicitly decouple the effect of mitigation measures in the Lower Jinsha River Basindue to the complexity associated with sediment redistribution within river channels(active channel migration and significant sedimentation). The whole basin can be subdivided into seven sub-regions according to the different proportional inputs of principal denudation processes to riverine SSY. In the Volga River Basin, anthropogenic sheet, rill and gully erosion are the predominant denudation processes in the southern region, while channel bank and bed erosion constitutes the main source of riverine suspended sediment flux in the northern part of the basin. Distribution of cultivated lands significantly determined the intensity of denudation processes.Local relief characteristics also considerably influence soil erosion rates and SSY in the southern Volga River Basin. Lithology, soil cover and climate conditions determined the spatial distribution of sheet, rill and gully erosion intensity, but they play a secondary role in SSY spatial variation.展开更多
A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all node...A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all nodes on the walls of a cube with a side-length of 2 m are computed under a reference-charge explosion at each node of its inner space using the LS-DYNA software, and then are collected to form a reference database. Next, with the thought of the isoparametric finite element, an interpolating algori...展开更多
Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil...Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil in the global carbon cycle and provide a scientific basis for the assessment of the magnitude of carbon stored in a given area. Here we present estimates of soil organic carbon stock in soils in the upper reaches of the Yangtze River based on soil types as defined by Chinese Soil Taxonomy and recently compiled into a digital soil database. The results showed that the total soil organic carbon stock of the upper Yangtze River to a depth of 100 cm was 1.452x1013 kg. The highest soil organic carbon stock was found in felty soils (2.419x10TM kg), followed by dark brown soils (1.269x10=kg), and dark feltysoils (L139x10=kg). Chernozems and irrigation silting soils showed the lowest soil organic carbon stock, mainly due to the small total area of such soils. The soil organic carbon density of these major soil types ranged from 5.6 to 26.1 kg m2- The average soil organic carbon density of the upper reaches of the Yangtze River was 16.4 kg m-2, which was higher than that of the national average. Soil organic carbon density indicated a distinct decreasing trend from west to east, which corresponds to the pattern of increasing temperature from cold to subtropical.展开更多
AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of the...AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of themismatch repair(MMR)machinery in colorectal tumors.METHODS:The CA-SSRⅠgenotype was analyzed ina total of 86 primary colorectal tumors,selected upontheir microsatellite instability(MSI)status[42 with highfrequency MSI(MSI-H)and 44 microsatellite stable(MSS)]and their respective normal tissue.The effect of the CA-SSRⅠgenotype on the expression of the EGFR gene wasevaluated in 18 specimens using quantitative real-timereverse transcription PCR and immunohistochemistry.RESULTS:Mutations in CA-SSRⅠwere detected in 86%(36 of 42)of MSI-H colorectal tumors and 0%(0 of 44)ofMSS tumors,indicating the EGFR gene as a novel putativespecific target of the defective MMR system(P<0.001).Impaired expression of EGFR was detected in most ofthe colorectal tumors analyzed[6/12(50%)at the mRNAlevel and 15/18(83%)at the peptide level].However,noassociation was apparent between EGFR expression andCA-SSRⅠstatus in tumors or normal tissues.CONCLUSION:Our results suggest that CA-SSRⅠsequence does not contribute to the regulation of EGFRtranscription in colon,and should thus not be consideredas a promising predictive marker for response to EGFRinhibitors in patients with colorectal cancer.展开更多
The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β...The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β) were greatly affected by incoming shortwave radiation and canopy growth.During the non-growing season and early-growing season, sensible heat(H) dominated the energy flux, and β could reach a maximum of 2.5, while during most of the growing season, latent heat dominated the energy flux and β fluctuated from 0.4 to 1.0.The energy budget ratio in growing season was about 0.76, and the value would be higher if heat exchange during tidal flooding was in-cluded.During tidal flooding days, β was slightly higher than that at exposure days in most cases.Vegetation cover seems exert little effect on energy partitioning except in March when the standing dead grass intercepted the incoming radiation that might reach the soil surface and reduce the turbulence between soil and atmosphere, thus suppressing the evaporation from the soil though the soil mositure was high at that time.展开更多
AIM: To explore the effects of recombinant human growth hormone (rhGH) on intestinal mucosal epithelial cell proliferation and nutritional status in patients with enterocutaneous fistula. METHODS: Eight patients w...AIM: To explore the effects of recombinant human growth hormone (rhGH) on intestinal mucosal epithelial cell proliferation and nutritional status in patients with enterocutaneous fistula. METHODS: Eight patients with enterocutaneous fistulas received recombinant human growth hormone (10 ug/d) for 7 d. Image analysis and immunohistochemical techniques were used to analyse the expression of proliferating cell nuclear antigen (PCNA) in intestinal mucosal epithelial cells in biopsy samples from the patients who had undergone an endoscopic biopsy through the fistula at day 0, 4 and 7. Body weights, nitrogen excretion, serum levels of total proteins, albumin, prealbumin, transferrin and fibronectin were measured at day 0, 4 and 7. RESULTS: Significant improvements occurred in the expression of PCNA in the intestinal mucosal epithelial cells at day 4 and 7 compared to day 0 (24.93 ± 3.41%, 30.46 ± 5.24% vs 12.92 ± 4.20%, p 〈 0.01). These changes were accompanied by the significant improvement of villus height (500.54 ± 53.79 um, 459.03 ± 88.98um vs 210.94 ± 49.16 um, P 〈 0.01), serum levels of total proteins (70.52 ± 5.13 g/L, 74.89 ± 5.16 g/L vs 63.51 ± 2.47 g/L, P 〈 0.01), albumin (39.44 ± 1.18 g/L, 42.39 ± 1.68 g/L vs 35.74 ± 1.75 g/L, P 〈 0.01) and fibronectin (236.3 4- 16.5 mg/L, 275.8± 16.9 mg/L vs 172.5 ± 21.4 mg/L, P 〈 0.01) at day 4 and 7, and prealbumin (286.38 ± 65.61 mg/L vs 180.88 ± 48.28 mg/L, P 〈 0.05), transferrin (2.61 ± 0.12 g/L vs 2.41 ±0.14 g/L, P 〈 0.05) at day 7. Nitrogen excretion was significantly decreased at day 7 (3.40 ± 1.65 g/d vs 7.25 ± 3.92 g/d, P 〈 0.05). No change was observed in the body weight. CONCLUSION: Recombinant human growth hormone could promote intestinal mucosal epithelial cell proliferation and protein synthesis in patients with enterocutaneous fistula.展开更多
Objective: To detect the expressions of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in purified rat choroid plexus epithelial cells in vitro. Methods: Primary and passage choroid plexu...Objective: To detect the expressions of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in purified rat choroid plexus epithelial cells in vitro. Methods: Primary and passage choroid plexus epithelial cells were obtained from newborn, one-day Spragne-Dawley rats. The expressions of BDNF and NGF were measured by qRT-PCR and Western blottingting. The secretions of BDNF and NGF were detected by ELISA. Cell supematants of primary cells, purified cells and passage 1 cells were harvested. Results: The expression of BDNF in the purified cells was significantly lower than that in the primary cells (P〈0.05), and it in the primary cells and the purified cells was significantly higher than that in the passage 1 cells (P〈0.05). The expression of NGF was significantly higher in the purified cells than in the primary cells and the passage 1 cells (P〈0.05). It in the passage 1 cells was significantly higher than that in the primary cells (P〈0.05). Conclusion: The time of CPECs transplantation for central nervous system diseases should be selected based on their secretory function and features,which could lead to better and more effective treatment.展开更多
基金Supported by National Natural Science Fund(70861004)~~
文摘According to the characteristics of circular agricultural mode focusing on pig farming and by dint of system dynamics mode-based analysis techniques to analyze the characteristics,the operation force for the recycling agricultural system focusing on pig farming was put forward.
基金Supported by Science and Technology Project of Guangdong Province(2008B020400015,2006B20301045)~~
文摘[Objective] The aim was to investigate the effects of Primo MAXX growth regulator on growth of Bermuda grass,explore appropriate application concentration of Primo MAXX on Bermuda grass,and provide basis for the application of Primo MAXX in Bermuda meadow.[Method]The height,leaf colour and the aerial part's fresh weight of Bermuda grass treated with different concentrations were researched using single factor random block test.[Result]Primo MAXX application effectively reduced the height in all treatment without significant difference;appropriate application of Primo MAXX can enrich the color;and 35 days after application,Bermuda grass roots were become thicker.[Conclusion]The application of Primo MAXX with effective dose of 150-300 g/hm2 on Bermuda grass in southern China is more appropriate.
基金The Doctoral Fund from the Ministry of Education of China, No. BXJ0710
文摘AIM: To study the inhibitory effect of baculovirus- mediated normal epithelial cell specific-1 (NES1) gene therapy on gastric cancer (GC) in vitro and in vivo. METHODS: We first constructed recombinant baculovirus vectors and then transfected them into gastric cancer cells (SGC-7901). Efficiency of the baculovirus for gene transfer into SGC-7901 cells and cell growth curves were detected by fluorescence microscopy, Western blot and 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in vitro, respectively. The therapeutic effect of this gene therapy on GC was confirmed in xenografted nude mice. Tumor growth was determined by tumor volume, and expression of NES1 in tumor was analyzed by immunohistochemistry. RESULTS: Baculovirus vectors were successfully transfected into SGC-7901 cells. SGC-7901 cells transfected with the NES1 gene inhibited cell growth. In the Bac-NES1 treated group, tumor growth was significantly reduced with a high level of NES1 expression CONCLUSION: Baculovirus-mediated NES1 gene can be used in gene therapy for GC.
基金supported by the National Basic Research Program of China (2002CB412400)the Natural Science Foundation of Shandong Province (Y2007E14)+1 种基金the Doctoral Fund of Ministry of Education of China (200804231011)the Key Lab of Submarine Geosciences and Prospecting Techniques of the Ministry of Education
文摘Via the valuable opportunity of the Three Gorges Reservoir (TGR) 135-m filling in June 2003, the Yangtze discharge and suspended sediment concentration (SSC) entering the estuary during the period from 15 May to 15 July 2003 were analyzed to examine the instant effects of the filling on them. The Yangtze discharge and SSC entering the estuary in the periods before, during and after the filling clearly indicated three phases: 1) the pre-storage phase characterized by natural conditions, in which the SSC increased with increasing water discharge; 2) the storage phase, during which the SSC decreased dramatically with decreasing water discharge; and 3) the post-storage phase, during which both the SSC and water discharge remained at relatively low levels first until the end of June, then the SSC increased gradually with increasing water discharge. It seems that the times for the instant effects of the decreasing discharge downstream from the upper Yangtze on the Yangtze discharge and SSC entering the estuary due to the TGR 135-m filling to take place were about 5 d and 1 d respectively, while both were about 18 d for those of the increasing discharge. This probably reflects the buffering and resultantly hysteresis of the 1800-km stretch from the upper Yangtze to the estuary. The results are helpful for scientific and hydrological investigation of the Yangtze mainstream downstream from the TGR Dam and of the estuarine and adjacent coastal waters.
基金Supported by the National Natural Science Foundation of China, No. 90209023 the State 973 Project, No. 2005CB523308
文摘AIM: To investigate the effect of serum derived from rats treated with electroacupuncture at stomach meridian acupoints on the expression of epidermal growth factor receptor (EGFR) gene in gastric mucosal cells. METHODS: The stress-induced gastric mucosal injury in rat model was established by water-immersion and restrained stress methods. 52 rats were randomly divided into: normal group (n = 8), model group (n = 8), model serum group (n = 12), stomach serum group (n = 12), and gallbladder serum group (n = 12). The gastric mucosal cells were separated by pronase-EDTA digestion method and incubated with serum. The EGFR gene expression in gastric mucosal cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: Compared with normal group (0.6860 ± 0.0594), the serum derived from rats of the stomach group (1.2272 ± 0.0813, P = 0.00 < 0.01) and gallbladder group (0.9640 ± 0.0387, P = 0.00 < 0.01) had a tendency to enhance the EGFR gene expression in gastric mucosal cells. Such tendency existed in the model group (0.7104 ± 0.0457) but with no signifi cant difference (P = 0.495 > 0.05) and in model serum group (0.8516 ± 0.0409) with an extremely obvious difference (P = 0.001 < 0.01). Furthermore, the EGFR gene expression in stomach serum group was significantly higher than that in gallbladder serum group (P = 0.00 < 0.01). CONCLUSION: The present study shows that serumderived from rats treated with electroacupuncture at stomach meridian acupoints can distinctly increase the EGFR gene expression of gastric mucosal cells. Therefore, there is certain meridian specificity in the serum, which could provide a proof for the TCM theory “particular relation between meridian and internal organ”.
基金Supported by Deutsche Forschungsgemeinschaft (DFG),Deutsche Krebshilfe and Sonnenfeld-Stiftung Berlin
文摘AIM: To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma (HCC). METHODS: Erlotinib-induced alterations in gene expression were evaluated using cDNA array technology; changes in protein expression and/or protein activation due to erlotinib treatment as well as IGF-1-induced EGFR transactivation were investigated using Western blotting. RESULTS: Erlotinib treatment inhibited the mitogen activated protein (MAP)-kinase pathway and signal transducer of activation and transcription (STAT)- mediated signaling which led to an altered expression of apoptosis and cell cycle regulating genes as demonstrated by cDNA array technology. Overexpression of proapoptotic factors like caspases and gadds associated with a down-regulation of antiapoptotic factors like Bcl-2, Bcl-XL or jun D accounted for erlotinib's potency to induce apoptosis. Downregulation of cell cycle regulators promoting the G1/S-transition and overexpression of cyclin-dependent kinase inhibitors and gadds contributed to the induction of a G1/G0-arrest in response to erlotinib. Furthermore, we displayed the transactivation of EGFR-mediated signaling by the IGF-1-receptor and showed erlotinib's inhibitory effects on the receptor-receptor cross talk. CONCLUSION: Our study sheds light on the understanding of the mechanisms of action of EGFR-TK- inhibition in HCC-cells and thus might facilitate the design of combination therapies that act additively or synergistically. Moreover, our data on the pathways responding to erlotinib treatment could be helpful in predicting the responsiveness of tumors to EGFR-TKIs in the future.
基金Supported by the University of Louisville Hospital the Society for Surgery of the Alimentary Tract Career Development Award
文摘AIM: To investigate the expression of cyclooxygenase-2 (COX-2) and epithelial growth factor receptor (EGFR) throughout the progression of Barrett's esophagus (BE). METHODS: COX-2 and EGFR protein expressions were detected by using immunohistochemical method. A detailed cytomorphological changes were determined. Areas of COX-2 and EGFR expression were quantified by using computer Imaging System. RESULTS: The expressions of both COX-2 and EGFR increased along with the progression from BE to esophagus adenocarcinoma (EAC). A positive correlation was found between COX-2 expression and EGFR expression. CONCLUSION: COX-2 and EGFR may be cooperative in the stepwise progression from BE to EAC, thereby leading to carcinogenesis.
基金by the Natural Science Foundation of China (Grant No. 40801101)
文摘Subsurface flow is a prominent runoff process in sloping lands of purple soil in the upper Yangtze River basin.However,it remains difficult to identify and quantify.In this study,in situ runoff experimental plots were used to measure soil moisture dynamics using an array of time domain reflectometry(TDR) together with overland flow and subsurface flow using isolated collecting troughs.Frequency of preferential flow during rainfall events and the controls of subsurface flow processes were investigated through combined analysis of soil properties,topography,rainfall intensity,initial wetness,and tillage.Results showed that subsurface flow was ubiquitous in purple soil profiles due to welldeveloped macropores,especially in surface soils while frequency of preferential flow occurrence was very low(only 2 cases in plot C) during all 22 rainfall events.Dry antecedent moisture conditions promoted the occurrence of preferential flow.However,consecutive real-time monitoring of soil moisture at different depths and various slope positions implied the possible occurrence of multiple subsurface lateral flows during intensive storms.Rainfall intensity,tillage operation,and soil properties were recognized as main controls of subsurface flow in the study area,which allows the optimization of management practices for alleviating adverse environmental effects of subsurface flow in the region.
基金supported by National Natural Science Foundation of China (Grant No. 40971169,41101259)Ministry of Environmental Protectionof China (Grant No. 2009ZX07104-002-06)State Key Laboratory of Environmental Geochemistry (Grant No. SKLEG9008)
文摘137 Cs is an artificial radionuclide with a half-life of 30.2 years,which was released into the environment as a byproduct of atmospheric testing of nuclear weapons during the period of 1950s to 1970s with a peak deposition in 1963.137 Cs fallout was strongly and rapidly adsorbed by soil particles when it deposited on the ground mostly with precipitation.Its following movements will associate with the adsorbed particles.137 Cs tracing technique has been widely used in soil erosion and sedimentation studies since 1980s.This paper introduces the basis of the technique and shows several case studies of assessment of soil erosion rates,investigation of sediment sources and dating of reservoir deposits by using the technique in the Loess Plateau and the Upper Yangtze River Basin.
基金support for this study was jointly provided by the Chinese Academy of Sciences (No. ZCX2-XB3-09)the Ministry of Science and Technology of China (No. 2011BAD31B03)
文摘This paper synthesized the principal land denudation processes and their role in determining riverine suspended sediment yields(SSY) in two typical geographical environments of the Upper Yangtze River Basin in China and the Volga River Basin in Eastern Europe. In the Upper Yangtze River Basin, natural factors including topography, climate,lithology and tectonic activity are responsible for the spatial variation in the magnitude of denudation rates.Human disturbances have contributed to the temporal changes of soil erosion and fluvial SSY during the past decades. On one hand, land use change caused by deforestation and land reclamation has played an important role in the acceleration of sediment production from the central hilly area and lower Jinsha catchment; On the other hand, diverse soil conservation practices(e.g., reforestation,terracing) have contributed to a reduction of soil erosion and sediment production since the late 1980 s.It was difficult to explicitly decouple the effect of mitigation measures in the Lower Jinsha River Basindue to the complexity associated with sediment redistribution within river channels(active channel migration and significant sedimentation). The whole basin can be subdivided into seven sub-regions according to the different proportional inputs of principal denudation processes to riverine SSY. In the Volga River Basin, anthropogenic sheet, rill and gully erosion are the predominant denudation processes in the southern region, while channel bank and bed erosion constitutes the main source of riverine suspended sediment flux in the northern part of the basin. Distribution of cultivated lands significantly determined the intensity of denudation processes.Local relief characteristics also considerably influence soil erosion rates and SSY in the southern Volga River Basin. Lithology, soil cover and climate conditions determined the spatial distribution of sheet, rill and gully erosion intensity, but they play a secondary role in SSY spatial variation.
基金Supported by National Natural Science Foundation of China (No. 50678116)National Key Technology R&D Program of China (No. 2006BAJ13B02)Tianjin Municipal Major Project of Application Foundation and Frontal Technology Research (No. 08JCZDJC19500)
文摘A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all nodes on the walls of a cube with a side-length of 2 m are computed under a reference-charge explosion at each node of its inner space using the LS-DYNA software, and then are collected to form a reference database. Next, with the thought of the isoparametric finite element, an interpolating algori...
基金funded by Special Program of Strategic Science and Technology of Chinese Academy of Sciences (Grant No. XDA05050506)State Key and Basic Research Development Planning (Grant No. 2012CB417101)+1 种基金Project of Natural Science Foundation of China (Grant No. 40901134)West Light Foundation of Chinese Academy of Sciences
文摘Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil in the global carbon cycle and provide a scientific basis for the assessment of the magnitude of carbon stored in a given area. Here we present estimates of soil organic carbon stock in soils in the upper reaches of the Yangtze River based on soil types as defined by Chinese Soil Taxonomy and recently compiled into a digital soil database. The results showed that the total soil organic carbon stock of the upper Yangtze River to a depth of 100 cm was 1.452x1013 kg. The highest soil organic carbon stock was found in felty soils (2.419x10TM kg), followed by dark brown soils (1.269x10=kg), and dark feltysoils (L139x10=kg). Chernozems and irrigation silting soils showed the lowest soil organic carbon stock, mainly due to the small total area of such soils. The soil organic carbon density of these major soil types ranged from 5.6 to 26.1 kg m2- The average soil organic carbon density of the upper reaches of the Yangtze River was 16.4 kg m-2, which was higher than that of the national average. Soil organic carbon density indicated a distinct decreasing trend from west to east, which corresponds to the pattern of increasing temperature from cold to subtropical.
文摘AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of themismatch repair(MMR)machinery in colorectal tumors.METHODS:The CA-SSRⅠgenotype was analyzed ina total of 86 primary colorectal tumors,selected upontheir microsatellite instability(MSI)status[42 with highfrequency MSI(MSI-H)and 44 microsatellite stable(MSS)]and their respective normal tissue.The effect of the CA-SSRⅠgenotype on the expression of the EGFR gene wasevaluated in 18 specimens using quantitative real-timereverse transcription PCR and immunohistochemistry.RESULTS:Mutations in CA-SSRⅠwere detected in 86%(36 of 42)of MSI-H colorectal tumors and 0%(0 of 44)ofMSS tumors,indicating the EGFR gene as a novel putativespecific target of the defective MMR system(P<0.001).Impaired expression of EGFR was detected in most ofthe colorectal tumors analyzed[6/12(50%)at the mRNAlevel and 15/18(83%)at the peptide level].However,noassociation was apparent between EGFR expression andCA-SSRⅠstatus in tumors or normal tissues.CONCLUSION:Our results suggest that CA-SSRⅠsequence does not contribute to the regulation of EGFRtranscription in colon,and should thus not be consideredas a promising predictive marker for response to EGFRinhibitors in patients with colorectal cancer.
基金Under the auspices of National Natural Science Foundation of China (No. 30870409,40471087)Science and Technology Commission of Shanghai (No. 07DZ12038-2)the Program for New Century Excellent Talents in University (No.NCET-06-0364) funded by the Ministry of Education of China
文摘The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β) were greatly affected by incoming shortwave radiation and canopy growth.During the non-growing season and early-growing season, sensible heat(H) dominated the energy flux, and β could reach a maximum of 2.5, while during most of the growing season, latent heat dominated the energy flux and β fluctuated from 0.4 to 1.0.The energy budget ratio in growing season was about 0.76, and the value would be higher if heat exchange during tidal flooding was in-cluded.During tidal flooding days, β was slightly higher than that at exposure days in most cases.Vegetation cover seems exert little effect on energy partitioning except in March when the standing dead grass intercepted the incoming radiation that might reach the soil surface and reduce the turbulence between soil and atmosphere, thus suppressing the evaporation from the soil though the soil mositure was high at that time.
基金Supported by National Natural Science Foundation of China, No. 30571797National Natural Science Foundation of Jiangsu Province, No. BK2006719
文摘AIM: To explore the effects of recombinant human growth hormone (rhGH) on intestinal mucosal epithelial cell proliferation and nutritional status in patients with enterocutaneous fistula. METHODS: Eight patients with enterocutaneous fistulas received recombinant human growth hormone (10 ug/d) for 7 d. Image analysis and immunohistochemical techniques were used to analyse the expression of proliferating cell nuclear antigen (PCNA) in intestinal mucosal epithelial cells in biopsy samples from the patients who had undergone an endoscopic biopsy through the fistula at day 0, 4 and 7. Body weights, nitrogen excretion, serum levels of total proteins, albumin, prealbumin, transferrin and fibronectin were measured at day 0, 4 and 7. RESULTS: Significant improvements occurred in the expression of PCNA in the intestinal mucosal epithelial cells at day 4 and 7 compared to day 0 (24.93 ± 3.41%, 30.46 ± 5.24% vs 12.92 ± 4.20%, p 〈 0.01). These changes were accompanied by the significant improvement of villus height (500.54 ± 53.79 um, 459.03 ± 88.98um vs 210.94 ± 49.16 um, P 〈 0.01), serum levels of total proteins (70.52 ± 5.13 g/L, 74.89 ± 5.16 g/L vs 63.51 ± 2.47 g/L, P 〈 0.01), albumin (39.44 ± 1.18 g/L, 42.39 ± 1.68 g/L vs 35.74 ± 1.75 g/L, P 〈 0.01) and fibronectin (236.3 4- 16.5 mg/L, 275.8± 16.9 mg/L vs 172.5 ± 21.4 mg/L, P 〈 0.01) at day 4 and 7, and prealbumin (286.38 ± 65.61 mg/L vs 180.88 ± 48.28 mg/L, P 〈 0.05), transferrin (2.61 ± 0.12 g/L vs 2.41 ±0.14 g/L, P 〈 0.05) at day 7. Nitrogen excretion was significantly decreased at day 7 (3.40 ± 1.65 g/d vs 7.25 ± 3.92 g/d, P 〈 0.05). No change was observed in the body weight. CONCLUSION: Recombinant human growth hormone could promote intestinal mucosal epithelial cell proliferation and protein synthesis in patients with enterocutaneous fistula.
基金Supported by grants from the National Natural Science Foundation of China(No.30973099 and No.81271341)
文摘Objective: To detect the expressions of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in purified rat choroid plexus epithelial cells in vitro. Methods: Primary and passage choroid plexus epithelial cells were obtained from newborn, one-day Spragne-Dawley rats. The expressions of BDNF and NGF were measured by qRT-PCR and Western blottingting. The secretions of BDNF and NGF were detected by ELISA. Cell supematants of primary cells, purified cells and passage 1 cells were harvested. Results: The expression of BDNF in the purified cells was significantly lower than that in the primary cells (P〈0.05), and it in the primary cells and the purified cells was significantly higher than that in the passage 1 cells (P〈0.05). The expression of NGF was significantly higher in the purified cells than in the primary cells and the passage 1 cells (P〈0.05). It in the passage 1 cells was significantly higher than that in the primary cells (P〈0.05). Conclusion: The time of CPECs transplantation for central nervous system diseases should be selected based on their secretory function and features,which could lead to better and more effective treatment.