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41.
Syntheses of 3,3-diheteroaromatic oxindole derivatives has been achieved by coupling indole-2,3-dione (isatin) with differently substituted indoles and pyrrole in presence of I2 in i-PrOH. The in vitro spermicidal potentials and the mode of spermicidal action of the synthesized analogues were evaluated and the derivative, 3,3-bis (5-methoxy-1H-indol-3-yl) indolin-2-one (3d) exhibited most significant activity.  相似文献   
42.
We describe herein a one-pot synthesis of novel tetracyclic scaffolds that incorporate a fusion of a proline, 1,2,3-triazole ring with [1,4]-benzodiazepin-8(4H)-one ring systems following click chemistry. The expected peptide bond formation followed by in situ 1,3-dipolar cycloaddition in absence of any catalyst led to the formation of new triazole fused benzodiazepine derivatives.  相似文献   
43.
A water-soluble polysaccharide of an edible mushroom Calocybe indica var. APK2 showed immunoenhancing (macrophage, splenocyte, thymocyte, and bone marrow activation) and cytotoxic activity toward HeLa cell lines and found to consist of d-glucose, d-galactose, and l-fucose in a molar ratio of nearly 3:1:1. On the basis of acid hydrolysis, methylation analysis, and NMR studies (1H, 13C, DEPT-135, TOCSY, DQF–COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of the fuco-galacto-glucan was established as:  相似文献   
44.
A water-soluble polysaccharide was isolated from the aqueous extract of the fruit bodies of somatic hybrid PCH9FB, obtained through intergeneric protoplast fusion between the strains Pleurotus florida and Calocybe indica var. On the basis of total acid hydrolysis, the polysaccharide was found to contain galactose, fucose, and glucose in a molar ratio of nearly 2:1:2. Methylation analysis and NMR experiments ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) showed that the structure of the repeating unit present in the polysaccharide was This molecule showed macrophage, splenocyte, thymocyte activation as well as antioxidant property.  相似文献   
45.
Electron transfer (ET) reactions are important for their implications in both oxidative and reductive DNA damages. The current contribution investigates the efficacy of caffeine, a xanthine alkaloid in preventing UVA radiation induced ET from a carcinogen, benzo[a]pyrene (BP) to DNA by forming stable caffeine–BP complexes. While steady‐state emission and absorption results emphasize the role of caffeine in hosting BP in aqueous medium, the molecular modeling studies propose the energetically favorable structure of caffeine–BP complex. The picosecond‐resolved emission spectroscopic studies precisely explore the caffeine‐mediated inhibition of ET from BP to DNA under UVA radiation. The potential therapeutic activity of caffeine in preventing DNA damage has been ensured by agarose gel electrophoresis. Furthermore, time‐gated fluorescence microscopy has been used to monitor caffeine‐mediated exclusion of BP from various cell lines including squamous epithelial cells, WI‐38 (fibroblast), MCF‐7 (breast cancer) and HeLa (cervical cancer) cells. Our in vitro and ex vivo experimental results provide imperative evidences about the role of caffeine in modified biomolecular recognition of a model carcinogen BP by DNA resulting dissociation of the carcinogen from various cell lines, implicating its potential medicinal applications in the prevention of other toxic organic molecule induced cellular damages. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
46.

SUMMARY

All living organisms are continuously faced with endogenous or exogenous stress conditions affecting genome stability. DNA repair pathways act as a defense mechanism, which is essential to maintain DNA integrity. There is much to learn about the regulation and functions of these mechanisms, not only in human cells but also equally in divergent organisms. In trypanosomatids, DNA repair pathways protect the genome against mutations but also act as an adaptive mechanism to promote drug resistance. In this review, we scrutinize the molecular mechanisms and DNA repair pathways which are conserved in trypanosomatids. The recent advances made by the genome consortiums reveal the complete genomic sequences of several pathogens. Therefore, using bioinformatics and genomic sequences, we analyze the conservation of DNA repair proteins and their key protein motifs in trypanosomatids. We thus present a comprehensive view of DNA repair processes in trypanosomatids at the crossroads of DNA repair and drug resistance.  相似文献   
47.
International Journal of Biometeorology - The aim of this study was to estimate, using data mining, which microclimate and behavioral variables affect the behavior of animals to seek shaded or...  相似文献   
48.
D K Das  J Iyengar  R M Jones  D Lu  S Maity 《Cryobiology》1991,28(2):177-184
A recent study from our laboratory indicated additional tissue injury during rewarming of a cooled rabbit leg. Oxygen-derived free radicals were believed to play a role in such "rewarming injury." Since free radicals may attack membrane phospholipids, we analyzed the phospholipid composition in the leg tissue during cooling and rewarming. Our results indicated significant breakdown of membrane phospholipids, particularly phosphatidylcholine and phosphatidylethanolamine, with a corresponding accumulation of lysophosphatidylcholine and nonesterified fatty acids. Quinacrine, a phospholipase inhibitor, was able to preserve membrane phospholipids during rewarming of the cooled leg. Rewarming of cooled tissue was also accompanied by additional tissue injury, as evidenced by the increased release of lactic acid dehydrogenase and creatine kinase, as well as enhanced lipid peroxidation, as evidenced by increased malonaldehyde formation. Quinacrine reduced the release of these intracellular enzymes and decreased lipid peroxidation, suggesting its efficacy as a therapeutic agent against hypothermic injury.  相似文献   
49.
50.
Information on the use of buffalo follicular fluid (buFF) in modulation of ovarian functions in farm animals is scanty compared to other species. This is an attempt to investigate the effect of direct administration and active immunization of 30 kDa and above buFF proteins on ovarian functions in goats. Treatment of goats (n = 6) with steroid free 30 kDa and above buFF protein fraction during late-luteal phase for 4 days (days 12 or 13 to days 15 or 16) of the natural cycle, delayed the onset of estrus by 24 h compared to control although the mean duration of estrus was unaffected. A 71% increase (P = 0.06) in mean ovulation number was also observed following treatment. However, the population of large (> or =5 mm diameter) follicle was not affected. The ovarian activity calculated as total of ovulation and large follicles increased (1.6 times) significantly (P = 0.02) in treated animals. Active immunization of goats (n = 5) against these proteins did not affect the onset and duration of estrus. Similarly, the ovulation rate, number of large follicles and the ovarian activity did not differ significantly between immunized and control groups. The study revealed that 30 kDa and above buffalo follicular fluid contains some factor(s) that cause delay in the onset of estrus in goats and increase the ovulation rate. Active immunization against these proteins in goat did not show any effect either on onset, duration of estrus or ovulation rate and large follicle population. Detailed study on these buffalo follicular fluid proteins may help to use them further for modulation of ovarian function in farm animals.  相似文献   
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