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121.
Alcohol induced oxidative stress is linked to the metabolism of ethanol. In this study it has been observed that administration of ethanol in lower concentration caused gain in body and liver weight. while higher concentration of ethanol caused lesser gain in body and liver weight. Ethanol treatment enhanced lipid peroxidation significantly, depletion in levels of hepatic glutathione and ascorbate, accompanied by a decline in the activities of glutathione peroxidase and glutathione reductase, and increased in hepatic glutathione s-transferase activity. Interestingly catalase activity increases in lower concentration of ethanol exposure, and decreased in higher concentration. Superoxide dismutase activity was also increased on ethanol exposure. But, ethanol feeding did not show any effect on glucose-6-phosphate dehydrogenase activity. Ethanol ingestion perturbs the antioxidant system in a dose and time dependent manner.  相似文献   
122.
Ethanol-induced liver injury may be linked, at least partly, to an oxidative stress resulting from increased free radical production and/or decreased antioxidant defence. Distinguishing alcoholic and non-alcoholic liver disease has important implications. This study looked at the possible changes between alcoholic and non-alcoholic liver diseases by examining the presence of oxidative damage, as monitored by several parameters relating to oxidative stress. Lipid peroxides concentration, superoxide dismutase activity and glutathione S-transferase activity increased, where as glutathione content, glutathione peroxidase activity and glutathione reductase activity decreased among the tested subjects in comparison to normal healthy group. Determination of these parameters may be valuable in the evaluation of liver disease. However, oxidative stress related enzymes and non-enzymes can not be utilized as a marker for alcoholic liver diseases, as these parameters responded in the same way after liver is damaged irrespective of their cause. Their level may help in determining the degree of liver damage. Degree of oxidative injury was similar in patients with non-alcoholic liver disease and in moderate drinkers; while significantly higher in heavy drinkers. The differences between the groups might be based on the type of liver pathological condition rather than its etiology (i.e. alcohol and non alcohol related causes).  相似文献   
123.
A simple, highly sensitive, direct, competitive ELISA for human serum testosterone has been indigenously developed. Specific antisera against testosterone were raised in rabbits using testosterone—3carboxymethyl oxime (CMO)—bovine serum albumin (BSA) as the antigen. For the enzyme conjugate, testoterone—3CMO was coupled with horse raddish peroxidase by the active ester method. The standard curve covered a wide range from 3.9 pg/ml to 500 pg/ml. The inter and intra-assay variation were found to be low and within the acceptable limits. Specificity and accuracy for the assay was established by having negligible crossreactivity with the related steroids and an excellent parallelism between the sample and standard dilution curve. Samples measured by RIA and ELISA showed very high degree of correlation (r=0.991).  相似文献   
124.
A decrease in the membrane anchored erythrocyte complement receptor 1 (CR1) is reported as an acquired phenomenon in a number of inflammatory and autoimmune diseases with concomitant rise in soluble CR1 (sCR1) levels in plasma. There is a need to establish the normal range of sCR1 in Indian adults to assess the function and disease association of this protein. The plasma sCR1 levels of 50 healthy individuals have been estimated by an indigenously developed sandwich ELISA. sCR1 levels from 26 patients suffering from nephropathies had also been assayed which was much higher than the normal controls. This observation suggests sCR1 as a potential market for the assessment of disease activity in nephropathies.  相似文献   
125.
Alcohol induced effects on kidney   总被引:1,自引:1,他引:0  
After administration ethanol and its metabolites go through kidneys and are excreted into urine, and its content in the urine is higher than that of the blood and the liver. Chronic ethanol administration decreases the renal tubular reabsorption and reduces renal function. Multiple functional abnormalities of renal tubules may be associated with ethanol-induced changes in membrane composition and lipid peroxidation. The vulnerability of the kidney to oxidative damage has been partly attributed to its high content of long-chain polyunsaturated fatty acids. Renal ultra structural abnormalities due to ethanol exposure may be important in the genesis of functional disturbances. Increased oxidative stress and endothelial dysfunction with their complex interrelationships are relevant aspects of atherogenesis in chronic renal failure. Antioxidants, particularly polyphenols are expected to decrease the vulnerability of the kidney to oxidative challenges.  相似文献   
126.
Alcohol appears to affect brain function, primarily by interfering with the action of gamma-aminobutyric acid (GABA) and other neurotransmitters. As alcohol is mainly metabolized in the liver, therefore we undertook this pilot study to monitor the patterns of changes in plasma amino-acid concentrations due to alcoholic and nonalcohol fatty liver disease and their relation with plasma GABA level. Plasma amino-acid concentrations were measured in 25 alcoholic liver disease (ALD) patients, 18 non-alcoholic fatty liver disease (NAFLD) patients, and 24 age and sex matched control subjects by HPLC. GABA concentration was elevated, while isoleucine and leucine levels reduced significantly in ALD patients compared to the control subjects. Methionine and phenylalanine levels elevated and valine content reduced significantly in ALD patients compared to other two groups, and GABA level was significantly correlated with methionine and phenylalanine. Plasma concentration of lysine was significantly reduced in both groups of liver disease patients compared to the control group, but was not correlated with GABA level. Glycine and tyrosine levels reduced significantly in NAFLD patients compared to other two groups and were significantly correlated with GABA. Interestingly, though amino acids such as alanine, histidine, proline and serine were not affected by liver diseases, but were significantly correlated with GABA level. This pilot study indicated that alcoholic liver disease presented a more deranged plasma amino acid pattern than nonalcoholic, and the amino acid imbalances. More studies are necessary to identify the role of any particular amino acid on brain function and on neurotransmitter(s).  相似文献   
127.
Summary  Amoebiasis, caused by an enteric protozoanEntamoeba histolytica, is one of the major parasitic diseases of mankind. Current estimate suggests that the parasite infects about 10% of the world population at any given time. There is an urgent need to characterize the antigenic molecules ofE. histolytica, and find out antigens which have both immunodiagnostic and prophylactic potential against amoebiasis. The results of somatic antigen analysis, using sera from immune or infected individuals, indicated that the wholeE. histolytica trophozoites, are highly complex and heterogeneous in nature and both immunodiagnostic and immuno prophylaxis activity remain mainly in a surface associated 29 kDa glycoprotein ofE. histolytica. Future studies at molecular level particularly, genes responsible for expression of this protein, their homology with other proteins and structure analysis will give better understanding about this polypeptide. Studies on excretory secretory antigens, clearly demonstrated thatE. histolytica like many organisms, also liberates certain antigenic moieties into the culture medium during in vitro cultivation and this antigen has similar diagnostic values like the conventional somatic antigens. It is important that the ESA should be prepared from the supernatant after collecting the cell and use for immunodiagnosis of amoebiasis. This is an additional source of antigen which will help in carrying out more tests using the same reagents. Further studies are needed to clarify the location of these molecules on the parasite, along with detailed biochemical and immunological characterization and their relation with the pathogenesis. This was presented at the symposium on “Recent Trends in Tropical Disease Research”, held at Sevagram on 5-6 September, 1997.  相似文献   
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Exploiting variation in welfare reform across states and over time and using relevant comparison groups, this study estimates the effects of welfare reform on an important source of human capital acquisition among women at risk for relying on welfare: vocational education and training. The results suggest that welfare reform reduced enrollment in full-time vocational education and had no significant effects on part-time vocational education or participation in other types of work-related courses, though there appears to be considerable heterogeneity across states with respect to the strictness of educational policy and the strength of work incentives under welfare reform. In addition, we find evidence of heterogeneous effects by prior educational attainment. We find no evidence that the previously observed negative effects of welfare reform on formal education (including college enrollment), which we replicated in this study, have been offset by increases in vocational education and training.  相似文献   
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