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41.
Previous studies indicated that chlorogenic acid, a compound present in many fruits and vegetables, has anti-cancer activities. We report that chlorogenic acid regulates the expression of apoptosis-related genes and self-renewal-related stem cell markers in cancer cells. The lung cancer cell line A549 was cultured with or without chlorogenic acid. The presence of chlorogenic acid decreased cell proliferation as measured by MTT activity. Polymerase chain reaction (PCR) showed that treatment of cells with chlorogenic acid reduced the expression of BCL2 but increased that of both BAX and CASP3. Chlorogenic acid enhanced annexin V expression as measured using fluorescently labeled annexin V. Chlorogenic acid also induced p38 MAPK and JNK gene expression. Meanwhile, several agents, including SB203580 (p38 MAP kinase inhibitor), N-acetylcysteine (antioxidant inhibitor), dipyridamole (phosphodiesterase inhibitor), and apocynin (NADPH-oxidase inhibitor) blocked chlorogenic acid-induced BAX gene expression. Chlorogenic acid reduced gene expression levels of stem cell-associated markers NANOG, POU5F1, and SOX2. Together these results indicate that chlorogenic acid affects the expression of apoptosis-related genes that are part of oxidative stress and p38 MAP-dependent pathways, as well as genes encoding stem cell markers. In conclusion, chlorogenic acid may contribute to the polyphenolic anti-cancer effect associated with consumption of vegetables and fruits.  相似文献   
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A series of 4-aryl-thieno[1,4]diazepin-2-one were synthesized and evaluated for their antiproliferative activities against the A375P melanoma and U937 hematopoietic cell lines. Several compounds showed very potent antiproliferative activities toward both cell lines and the activities were better than that of sorafenib, the reference standard. Derivatives were made as amide (8a8i, 9a9m) and urea (10a10d, 11a11d) with diverse hydrophobic moieties. One of the most potent inhibitor 10d, 1-(4-((4-ethylpiperazin-1-yl)methyl)-3-(trifluoromethyl)phenyl)-3-(4-(2-oxo-2,3-dihydro-1H-thieno [3,4-b][1,4]diazepin-4-yl)phenyl)urea was found to be very potent inhibitor of multi-protein kinases including FMS kinase (IC50?=?3.73?nM) and is a promising candidate for further development in therapeutics for cancer.  相似文献   
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When Physarumpolycephalum is pulse-labeled for up to 20 minutes with 3H-thymidine and the shortest labeled DNA strands are partially purified by sedimentation through a neutral aqueous sucrose gradient and then through a formamide-sucrose gradient, these short strands band in Cs2SO4 isopycnic density gradients at a density greater than that of bulk single-stranded DNA. Their density is brought partially or nearly completely back to that of single-stranded DNA by hydrolysis with pancreatic RNase A or alkali, respectively. Therefore the dense material attached to the short pulse-labeled DNA strands consists at least partially of RNA.  相似文献   
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The stereospecific reduction of 6-Br-β-tetralone to its corresponding alcohol (S)-6-Br-β-tetralol was carried out by the yeast Trichosporon capitatum MY1890 and by the bacterium Rhodococcus erythropolis MA7213, using a range of ionic liquids chosen for the diversity of their composition. The decrease in cell viability of both types of cell upon exposure to ionic liquids was found to be between that determined for cells residing purely in fermentation media, and cells residing in a two-phase mixture of media and organic solvent (toluene). For T. capitatum MY1890 bioconversions, the water miscible hydrophilic ionic liquid [Emim][TOS] gave a reaction profile comparable to that observed in the previously studied water-ethanol (10% v/v) system, in terms of overall rate of reaction (0.2 g (prod) L-1 h-1) and conversion (100%). Of the hydrophobic ionic liquids evaluated, [Oc3MeN][BTA] gave the best conversion of 60%, but at a much reduced rate, suggesting solute mass transfer from the ionic liquid phase was rate limiting. For bioconversions carried out with R. erythropolis MA7213 employing 20% v/v [Emim][TOS] as a co-solvent, the conversion yield doubled, and a four-fold increase in initial rate was found compared to the standard ethanol co-solvent. This was attributed to improved cell viability and reduced aggregation of the R. erythropolis MA7213 compared to T. capitatum MY1890. Overall, this study demonstrates the feasibility of using ionic liquids for whole cell biocatalysis, however, no obvious link is apparent between the physico-chemical properties of ionic liquids, their influence on cell viability, and their efficacy as media for bioconversions.  相似文献   
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Chrysoperla carnea (Stephens) is an important biological control agent currently being used in many integrated pest management (IPM) programs to control insect pests. The effect of post-treatment temperature on insecticide toxicity of a spinosyn (spinosad), pyrethroid (lambda cyhalothrin), organophosphate (chlorpyrifos) and new chemistry (acetamiprid) to C. carnea larvae was investigated under laboratory conditions. Temperature coefficients of each insecticide tested were evaluated. From 20 to 40 °C, toxicity of lambda cyhalothrin and spinosad decreased by 2.15- and 1.87-fold while toxicity of acetamiprid and chlorpyrifos increased by 2.00 and 1.79-fold, respectively. The study demonstrates that pesticide effectiveness may vary according to environmental conditions. In cropping systems where multiple insecticide products are used, attention should be given to temperature variation as a key factor in making pest management strategies safer for biological control agents. Insecticides with a negative temperature coefficient may play a constructive role to conserve C. carnea populations.  相似文献   
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Induction of Specific MicroRNAs Inhibits Cutaneous Wound Healing   总被引:1,自引:0,他引:1  
Chronic nonhealing wounds, such as venous ulcers (VUs), are a widespread and serious medical problem with high morbidity and mortality. The molecular pathology of VUs remains poorly understood, impeding the development of effective treatment strategies. Using mRNA expression profiling of VUs biopsies and computational analysis, we identified a candidate set of microRNAs with lowered target gene expression. Among these candidates, miR-16, -20a, -21, -106a -130a, and -203 were confirmed to be aberrantly overexpressed in a cohort study of 10 VU patients by quantitative PCR and in situ hybridizations. These microRNAs were predicted to target multiple genes important for wound healing, including early growth response factor 3, vinculin, and leptin receptor (LepR). Overexpression of the top up-regulated miRNAs, miR-21 and miR-130a, in primary human keratinocytes down-regulated expression of the endogenous LepR and early growth response factor 3. The luciferase reporter assay verified LepR as a direct target for miR-21 and miR-130a. Both miR-21 and miR-130a delayed epithelialization in an acute human skin wound model. Furthermore, in vivo overexpression of miR-21 inhibited epithelialization and granulation tissue formation in a rat wound model. Our results identify a novel mechanism in which overexpression of specific set of microRNAs inhibits wound healing, resulting in new potential molecular markers and targets for therapeutic intervention.  相似文献   
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