The paper first introduces the definition and classification of plant growth promoting rhizobacteria (PGPR), then reviews the research achievements on the mechanism of action of plant growth promoting rhizobacteria,...The paper first introduces the definition and classification of plant growth promoting rhizobacteria (PGPR), then reviews the research achievements on the mechanism of action of plant growth promoting rhizobacteria, including growth pro-moting mechanism and bio-control mechanism, subsequently lists the use of excel-lent plant growth promoting rhizobacteria strains in recent years, especial y Pseu-domonas and Bacil us strains, and final y discusses problems existing in this area and points out issues requiring further exploration, including PGPR screening meth-ods, preservation methods, mechanism of action, in order to commercialize PGPR as soon as possible and practical y realize its application to production.展开更多
Verbs of creation in English and Chinese demonstrate asymmetries in its projection to double-object construction. But underling the projection process there is a uniform operation mechanism, namely that the configurat...Verbs of creation in English and Chinese demonstrate asymmetries in its projection to double-object construction. But underling the projection process there is a uniform operation mechanism, namely that the configuration is affected by the interaction between the Meaning Assignment Principle (MAP), the Distance Principle of Iconicity (DPI) and the Lexical Feature Constraints (LFC), among which MAP and DPI are inviolable due to its cross-linguistic universality. Once LFC is violated, there must be compensation on the part of DPI, otherwise, the verb of creation in question would be unacceptable to double-object construction.展开更多
Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liqu...Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.展开更多
AIM;Oxidative stress participates in the cell carcinogenesis by inducing DNA mutations.Our aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing ROS(Reactive Oxygen Species)generation ...AIM;Oxidative stress participates in the cell carcinogenesis by inducing DNA mutations.Our aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing ROS(Reactive Oxygen Species)generation in experimental gastric carcinoma in a rat model. METHODS:Experimental gastric cancer was induced in twelve Wistar male rats(weighting 250-350 g)by profound duodeno-gastric reflux throught split gastrojenunostomy.The rats were allocated to the following groups:Group Ⅰ(n=6) was the control;Group Ⅱ(n=6)which was mantained with daily intake of tape water with Vitamin C(30 mg/Kg).After 6 or 12 months,samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups. Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with Nitrobluetetrazolium.The histopathologic confirmation of adenocarcinoma was made by eosin- hemathoxilin method. RESULTS:The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰ whereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of them.The cancers were located in the anastomosis in all cases.Basal luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/×10~6(mean±SD)and 14.9±4.0 count per minute/mg/×10~6,respectively,in group Ⅰ and Ⅱ animals(P <0.05).The Nitrobluetetrazolium method showed intense staining in tumor tissues but not in non neoplasic mucosa. CONCLUSION:Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric tissue.The reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic acid.Therefore,it may have a role in the prevention of gastric carcinoma. Oliveira CPMS Kassab P Lopasso FP Souza HP Janiszewski M Laurindo FRM Iriya K Laudanna AA.Protective effect of ascorbic acid in experimental gastric cancer:reduction of oxidative stress.World J Gastroenterol 2003;9(3):446-448 http://www.wjgnet.com/1007-9327/9/446.htm展开更多
TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repai...TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repair. A rabbit radial bone defect model was used to evaluate the effect of TGF-β, which was extracted and purified from bovine blood platelets, on the healing of a large segmental osteoperiosteal defect. A 1. 5-centimeter segmental defect was created in the mid-upper part of the radial shaft of adult rabbits. The defect was filled with implant containing TGF-β that consisted of carrier and bovine TGF-β. Limbs served as controls received carrier alone. The defectswere examined radiographically and histologically at 4, 8,12 , 16 and 20 weeks after implantation. The results showed that in TGF-β implant group . the defect areas at 12 weeks post operation were bridged by uniform new bone and the cut ends of cortex could not be seen;while in control group, the defects remained clear. Only a small amount of new bone formed as a cap on the cut bone ends. In the experimental group, new lamellar and woven bone formed in continuity with the cut ends of the cortex. An early medullar canal appears to be forming and contained normal-appearancing marrow elements; while the control group displayed entirely fibrous tissue within the defect site. Remnants of the cancellous bone carrier were observed in the control specimen. These data demonstrate that exogenous TGF-β initiate osteogenesis and stimulate the bone defects repair in animal model.展开更多
ObjectiveTo investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells invitroin culture medium were given different concentrations of oridonin. The inhibitory...ObjectiveTo investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells invitroin culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM),morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was det-ected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especi-ally after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells invitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.展开更多
AIM:Overexpression of mucosal metalloproteinases(MMP) has been demonstrated recently in inflammatory bowel disease.Their activity can be counterbalanced by the tissue inhibitor of metalloproteinases(TIMP).The aim of t...AIM:Overexpression of mucosal metalloproteinases(MMP) has been demonstrated recently in inflammatory bowel disease.Their activity can be counterbalanced by the tissue inhibitor of metalloproteinases(TIMP).The aim of this study was to evaluate the effect of ulcerative colitis(UC)on MMP- 1 and TIMP-1 plasma concentrations,as two possible biomarkers of the disease activity. METHODS:MMP-1 and TIMP-1 plasma concentrations were measured with an enzyme immunoassay in 16 patients with endoscopically confirmed active UC. RESULTS:Plasma concentrations of both MMP-1(13.7±0.2 ng/ml)and TIMP-1(799±140 ng/ml)were significantly elevated in UC patients in comparison to healthy controls (11.9±0.9 ng/ml and 220±7 ng/ml respectively).There was no correlation between TIMP-1 and MMP-1 concentrations (r=0.02).TIMP-1 levels revealed significant positive correlations with scored endoscopic degree of mucosal injury, disease activity index and clinical activity index values as well as C-reactive protein concentration.There was no correlation between MMP-1 and laboratory,clinical or endoscopic indices of the disease activity.CONCLUSION: These results confirm the role of both MMP- 1 and TIMP-1 in the pathogenesis of ulcerative colitis. However only TIMP-1 can be useful as a biomarker of the disease activity, demonstrating association with clinical and endoscopic pictures.展开更多
A study on the effect of Pb-Cd interaction on plant growth and on the chemistry of elements in plants was conducted under greenhouse condition with red soil-wetland rice system in different growth stage. The results s...A study on the effect of Pb-Cd interaction on plant growth and on the chemistry of elements in plants was conducted under greenhouse condition with red soil-wetland rice system in different growth stage. The results showed that Pb-Cd interactions on growth and metal uptake varied with different growth stageS and chemical compounds added. The plant height and the root weight were markedly affected by Pb-Cd interiction in the young stage but not in the ripening stage of rice at the treatments of PbCl_2 and CdCl_2 added. However, the weight of rice straw in the ripening stage was significantly effected by Pb-Cd interaction with the treatments of Pb(OAc)_2 and CdCl_2. The chemistry of elements in plants also depended on Pb-Cd interaction in varying degrees on account of different plant parts and growth stage. It seems that Pb-Cd interaction occurred not only in roots but also in other parts of wetland rice.展开更多
The liver is the main organ responsible for the metabolism of drugs and toxic chemicals, and so is the primary target organ for many organic solvents. Work activities with hepatotoxins exposures are numerous and, more...The liver is the main organ responsible for the metabolism of drugs and toxic chemicals, and so is the primary target organ for many organic solvents. Work activities with hepatotoxins exposures are numerous and, moreover, organic solvents are used in various industrial processes. Organic solvents used in different industrial processes may be associated with hepatotoxicity. Several factors contribute to liver toxicity; among these are: species differences, nutritional condition, genetic factors, interaction with medications in use, alcohol abuse and interaction, and age. This review addresses the mechanisms of hepatotoxicity. The main pathogenic mechanisms responsible for functional and organic damage caused by solvents are: inflammation, dysfunction of cytochrome P450, mitochondrial dysfunction and oxidative stress. The health impact of exposure to solvents in the workplace remains an interesting and worrying question for professional health work.展开更多
We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both t...We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both the total amylase and volume of pancreatic secretion.Cholecystokinin-A receptor antagonism abolished the stimulatory effect of somatostatin immunoneutralization.We conclude that somatostatin tonically inhibits pancreatic secretion in fasted rats via inhibition of the release or action of cholecystokinin.Furthermore,the source of these peptides is likely islet delta cells and intrapancreatic neurons,respectively.展开更多
In this experiment, expression of tissue-type plasminogen activator (t-PA) in smooth muscle cells (SMCs) was measured at different intervals after the arterial injury. In the normal iliac arteries, only low levels of ...In this experiment, expression of tissue-type plasminogen activator (t-PA) in smooth muscle cells (SMCs) was measured at different intervals after the arterial injury. In the normal iliac arteries, only low levels of t-PA activity were estimated. t-PA activity in extracts of the iliac arteries increased significantlyat the 4th day after the injury, equivalent to the process that SMCs migrated from the media to the intima,and the t-PA activity was then decreased approximately to the normal level at the 7th day. Coexistent to the above data, results from in situ hybridization showed that the expression of t-PA mRNA in the intima as well as media increased also significantly at the 4th day after the arterial injury, and at the 7th day, tPA mRNA was detected only in those SMCs locating closely adjacent to the internal elastic lamina. These results suggest that t-PA might play an important role in SMC migration following endothelial injury, andantagonism of t-PA expression and/or activity within the vessel wall might be helpful in intervening the de velopment of restenosis following angioplasty.展开更多
In a newborn rat model of sepsis, the changes of nitric oxide and the protective effects of methylene blue orland dexamethason were investigated. The results revealed that plasma nitric oxide levels were elevated at 6...In a newborn rat model of sepsis, the changes of nitric oxide and the protective effects of methylene blue orland dexamethason were investigated. The results revealed that plasma nitric oxide levels were elevated at 6 h and peaked at 12 h after bacterial challenge. The treatment with methylene or/and dexamethasone was found to blunt hypoglycemia and hyperlacticemia, to reduce the occurrence rate of loss of response to pain, and to prolong the survival time. Moreover, therapy by dexamethasone was shown to decrease the 24 h mortality. The results suggested that nitric oxide play an important role during the course of fatal P. aeruginosa sepsis, but it is clear that the clinical value of nitric oxide and its inhibitors need to be further studied.展开更多
In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle (CPB) succeed in developing resistance to most of the reg...In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle (CPB) succeed in developing resistance to most of the registered chemical insecticides. Consequently, heavy applications of chemical insecticides to control this pest become ineffective on a long-term basis and can lead to serious health and environmental problems. The use of natural enemies to control CPB is an interesting alternative to chemical means However, hand release of predators is not feasible on a large scale in the field. The main objective of this research study was to design and build a test bench to investigate the technical feasibility of mechanically releasing predators. The test bench consisted of a vertical chain conveyor mounted on two vertical shafts driven by an electric motor. Since the predators are small and fragile, they were placed in a specially designed container to preserve their physical integrity. Trials using this test bench showed that a carrier material was required, because most of the predators remained inside the container. The success of this mass predator release system will be highly valuable for the biological control of insect pests in many crops.展开更多
The present study was conducted in four districts of Telangana State of India with 120 respondents in which 60 were members and other 60 were non-members of DCSs (Dairy Co-operative Societies)/MPIs (Milk Producer I...The present study was conducted in four districts of Telangana State of India with 120 respondents in which 60 were members and other 60 were non-members of DCSs (Dairy Co-operative Societies)/MPIs (Milk Producer Institutions). Constraints perceived in dairy farming and suggestions elicited by members and non-members were noted, tabulated and analyzed. The major constraints perceived by half or more than half of members were scarcity of water (91.67%), lack of green fodder (88.33%), preferring NS (natural service) than AI (Artificial Insemination) (83.33%), negligence in feeding pregnant and dry animals (81.37%), insufficient loan amount (78.33%), tendency to feed only grass and brans (71.67%), lack of availability of sufficient labour (70.00%), lack of remunerative price for milk (66.67%), high cost of feed (61.67%), lack of fodder conservation (55.00%) and high cost of animals (50.00%). Whereas major constraints perceived by non-members were scarcity of water (96.67%), lack of green fodder (93.33%), preferring NS than AI (88.33%), lack of availability of sufficient labour (85.00%), negligence in feeding pregnant and dry animals (83.33%), tendency to feed only grass and brans (78.33%), high cost of animals (75.00%), complex procedure for obtaining loans (71.67%) and high cost of feed (66.67%). Suggestions elicited by members majorly were providing subsidy for purchase of animals/providing loans on par with the cost of animal (81.67%), enhancing the procurement price (70.00%), providing more incentives (60.00%), encouraging calf rearing (58.33%) and conducting frequent animal health camps (50.00%). In case of non-members major suggestions elicited were conducting frequent animal health camps (68.33%) and providing subsidy on purchase of animals/providing loans on par with the cost of animal (58.33%). Considering the above constraints perceived and suggestions elicited by dairy farmers a proper linkage strategy should be developed among private and public sectors in providing need based services to the dairy farmers.展开更多
基金Supported by the Science and Technology Project of Nanping Tobacco Company(201203)~~
文摘The paper first introduces the definition and classification of plant growth promoting rhizobacteria (PGPR), then reviews the research achievements on the mechanism of action of plant growth promoting rhizobacteria, including growth pro-moting mechanism and bio-control mechanism, subsequently lists the use of excel-lent plant growth promoting rhizobacteria strains in recent years, especial y Pseu-domonas and Bacil us strains, and final y discusses problems existing in this area and points out issues requiring further exploration, including PGPR screening meth-ods, preservation methods, mechanism of action, in order to commercialize PGPR as soon as possible and practical y realize its application to production.
文摘Verbs of creation in English and Chinese demonstrate asymmetries in its projection to double-object construction. But underling the projection process there is a uniform operation mechanism, namely that the configuration is affected by the interaction between the Meaning Assignment Principle (MAP), the Distance Principle of Iconicity (DPI) and the Lexical Feature Constraints (LFC), among which MAP and DPI are inviolable due to its cross-linguistic universality. Once LFC is violated, there must be compensation on the part of DPI, otherwise, the verb of creation in question would be unacceptable to double-object construction.
基金the Natural Science Foundation of Guangdong Province (No. 020839).
文摘Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.
文摘AIM;Oxidative stress participates in the cell carcinogenesis by inducing DNA mutations.Our aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing ROS(Reactive Oxygen Species)generation in experimental gastric carcinoma in a rat model. METHODS:Experimental gastric cancer was induced in twelve Wistar male rats(weighting 250-350 g)by profound duodeno-gastric reflux throught split gastrojenunostomy.The rats were allocated to the following groups:Group Ⅰ(n=6) was the control;Group Ⅱ(n=6)which was mantained with daily intake of tape water with Vitamin C(30 mg/Kg).After 6 or 12 months,samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups. Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with Nitrobluetetrazolium.The histopathologic confirmation of adenocarcinoma was made by eosin- hemathoxilin method. RESULTS:The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰ whereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of them.The cancers were located in the anastomosis in all cases.Basal luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/×10~6(mean±SD)and 14.9±4.0 count per minute/mg/×10~6,respectively,in group Ⅰ and Ⅱ animals(P <0.05).The Nitrobluetetrazolium method showed intense staining in tumor tissues but not in non neoplasic mucosa. CONCLUSION:Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric tissue.The reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic acid.Therefore,it may have a role in the prevention of gastric carcinoma. Oliveira CPMS Kassab P Lopasso FP Souza HP Janiszewski M Laurindo FRM Iriya K Laudanna AA.Protective effect of ascorbic acid in experimental gastric cancer:reduction of oxidative stress.World J Gastroenterol 2003;9(3):446-448 http://www.wjgnet.com/1007-9327/9/446.htm
文摘TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repair. A rabbit radial bone defect model was used to evaluate the effect of TGF-β, which was extracted and purified from bovine blood platelets, on the healing of a large segmental osteoperiosteal defect. A 1. 5-centimeter segmental defect was created in the mid-upper part of the radial shaft of adult rabbits. The defect was filled with implant containing TGF-β that consisted of carrier and bovine TGF-β. Limbs served as controls received carrier alone. The defectswere examined radiographically and histologically at 4, 8,12 , 16 and 20 weeks after implantation. The results showed that in TGF-β implant group . the defect areas at 12 weeks post operation were bridged by uniform new bone and the cut ends of cortex could not be seen;while in control group, the defects remained clear. Only a small amount of new bone formed as a cap on the cut bone ends. In the experimental group, new lamellar and woven bone formed in continuity with the cut ends of the cortex. An early medullar canal appears to be forming and contained normal-appearancing marrow elements; while the control group displayed entirely fibrous tissue within the defect site. Remnants of the cancellous bone carrier were observed in the control specimen. These data demonstrate that exogenous TGF-β initiate osteogenesis and stimulate the bone defects repair in animal model.
文摘ObjectiveTo investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells invitroin culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM),morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was det-ected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especi-ally after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells invitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.
文摘AIM:Overexpression of mucosal metalloproteinases(MMP) has been demonstrated recently in inflammatory bowel disease.Their activity can be counterbalanced by the tissue inhibitor of metalloproteinases(TIMP).The aim of this study was to evaluate the effect of ulcerative colitis(UC)on MMP- 1 and TIMP-1 plasma concentrations,as two possible biomarkers of the disease activity. METHODS:MMP-1 and TIMP-1 plasma concentrations were measured with an enzyme immunoassay in 16 patients with endoscopically confirmed active UC. RESULTS:Plasma concentrations of both MMP-1(13.7±0.2 ng/ml)and TIMP-1(799±140 ng/ml)were significantly elevated in UC patients in comparison to healthy controls (11.9±0.9 ng/ml and 220±7 ng/ml respectively).There was no correlation between TIMP-1 and MMP-1 concentrations (r=0.02).TIMP-1 levels revealed significant positive correlations with scored endoscopic degree of mucosal injury, disease activity index and clinical activity index values as well as C-reactive protein concentration.There was no correlation between MMP-1 and laboratory,clinical or endoscopic indices of the disease activity.CONCLUSION: These results confirm the role of both MMP- 1 and TIMP-1 in the pathogenesis of ulcerative colitis. However only TIMP-1 can be useful as a biomarker of the disease activity, demonstrating association with clinical and endoscopic pictures.
文摘A study on the effect of Pb-Cd interaction on plant growth and on the chemistry of elements in plants was conducted under greenhouse condition with red soil-wetland rice system in different growth stage. The results showed that Pb-Cd interactions on growth and metal uptake varied with different growth stageS and chemical compounds added. The plant height and the root weight were markedly affected by Pb-Cd interiction in the young stage but not in the ripening stage of rice at the treatments of PbCl_2 and CdCl_2 added. However, the weight of rice straw in the ripening stage was significantly effected by Pb-Cd interaction with the treatments of Pb(OAc)_2 and CdCl_2. The chemistry of elements in plants also depended on Pb-Cd interaction in varying degrees on account of different plant parts and growth stage. It seems that Pb-Cd interaction occurred not only in roots but also in other parts of wetland rice.
文摘The liver is the main organ responsible for the metabolism of drugs and toxic chemicals, and so is the primary target organ for many organic solvents. Work activities with hepatotoxins exposures are numerous and, moreover, organic solvents are used in various industrial processes. Organic solvents used in different industrial processes may be associated with hepatotoxicity. Several factors contribute to liver toxicity; among these are: species differences, nutritional condition, genetic factors, interaction with medications in use, alcohol abuse and interaction, and age. This review addresses the mechanisms of hepatotoxicity. The main pathogenic mechanisms responsible for functional and organic damage caused by solvents are: inflammation, dysfunction of cytochrome P450, mitochondrial dysfunction and oxidative stress. The health impact of exposure to solvents in the workplace remains an interesting and worrying question for professional health work.
文摘We used a potent and specific monoclonal antibody to somatostatin to test the physiologic inhibitory role of the tetradecapeptide somatostatin on pancreatic secretion.Somatostatin immunoneutralization increased both the total amylase and volume of pancreatic secretion.Cholecystokinin-A receptor antagonism abolished the stimulatory effect of somatostatin immunoneutralization.We conclude that somatostatin tonically inhibits pancreatic secretion in fasted rats via inhibition of the release or action of cholecystokinin.Furthermore,the source of these peptides is likely islet delta cells and intrapancreatic neurons,respectively.
文摘In this experiment, expression of tissue-type plasminogen activator (t-PA) in smooth muscle cells (SMCs) was measured at different intervals after the arterial injury. In the normal iliac arteries, only low levels of t-PA activity were estimated. t-PA activity in extracts of the iliac arteries increased significantlyat the 4th day after the injury, equivalent to the process that SMCs migrated from the media to the intima,and the t-PA activity was then decreased approximately to the normal level at the 7th day. Coexistent to the above data, results from in situ hybridization showed that the expression of t-PA mRNA in the intima as well as media increased also significantly at the 4th day after the arterial injury, and at the 7th day, tPA mRNA was detected only in those SMCs locating closely adjacent to the internal elastic lamina. These results suggest that t-PA might play an important role in SMC migration following endothelial injury, andantagonism of t-PA expression and/or activity within the vessel wall might be helpful in intervening the de velopment of restenosis following angioplasty.
文摘In a newborn rat model of sepsis, the changes of nitric oxide and the protective effects of methylene blue orland dexamethason were investigated. The results revealed that plasma nitric oxide levels were elevated at 6 h and peaked at 12 h after bacterial challenge. The treatment with methylene or/and dexamethasone was found to blunt hypoglycemia and hyperlacticemia, to reduce the occurrence rate of loss of response to pain, and to prolong the survival time. Moreover, therapy by dexamethasone was shown to decrease the 24 h mortality. The results suggested that nitric oxide play an important role during the course of fatal P. aeruginosa sepsis, but it is clear that the clinical value of nitric oxide and its inhibitors need to be further studied.
文摘In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle (CPB) succeed in developing resistance to most of the registered chemical insecticides. Consequently, heavy applications of chemical insecticides to control this pest become ineffective on a long-term basis and can lead to serious health and environmental problems. The use of natural enemies to control CPB is an interesting alternative to chemical means However, hand release of predators is not feasible on a large scale in the field. The main objective of this research study was to design and build a test bench to investigate the technical feasibility of mechanically releasing predators. The test bench consisted of a vertical chain conveyor mounted on two vertical shafts driven by an electric motor. Since the predators are small and fragile, they were placed in a specially designed container to preserve their physical integrity. Trials using this test bench showed that a carrier material was required, because most of the predators remained inside the container. The success of this mass predator release system will be highly valuable for the biological control of insect pests in many crops.
文摘The present study was conducted in four districts of Telangana State of India with 120 respondents in which 60 were members and other 60 were non-members of DCSs (Dairy Co-operative Societies)/MPIs (Milk Producer Institutions). Constraints perceived in dairy farming and suggestions elicited by members and non-members were noted, tabulated and analyzed. The major constraints perceived by half or more than half of members were scarcity of water (91.67%), lack of green fodder (88.33%), preferring NS (natural service) than AI (Artificial Insemination) (83.33%), negligence in feeding pregnant and dry animals (81.37%), insufficient loan amount (78.33%), tendency to feed only grass and brans (71.67%), lack of availability of sufficient labour (70.00%), lack of remunerative price for milk (66.67%), high cost of feed (61.67%), lack of fodder conservation (55.00%) and high cost of animals (50.00%). Whereas major constraints perceived by non-members were scarcity of water (96.67%), lack of green fodder (93.33%), preferring NS than AI (88.33%), lack of availability of sufficient labour (85.00%), negligence in feeding pregnant and dry animals (83.33%), tendency to feed only grass and brans (78.33%), high cost of animals (75.00%), complex procedure for obtaining loans (71.67%) and high cost of feed (66.67%). Suggestions elicited by members majorly were providing subsidy for purchase of animals/providing loans on par with the cost of animal (81.67%), enhancing the procurement price (70.00%), providing more incentives (60.00%), encouraging calf rearing (58.33%) and conducting frequent animal health camps (50.00%). In case of non-members major suggestions elicited were conducting frequent animal health camps (68.33%) and providing subsidy on purchase of animals/providing loans on par with the cost of animal (58.33%). Considering the above constraints perceived and suggestions elicited by dairy farmers a proper linkage strategy should be developed among private and public sectors in providing need based services to the dairy farmers.