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排序方式: 共有271条查询结果,搜索用时 265 毫秒
91.
Kathryn E. Barry Liesje Mommer Jasper van Ruijven Christian Wirth Alexandra J. Wright Yongfei Bai John Connolly Gerlinde B. De Deyn Hans de Kroon Forest Isbell Alexandru Milcu Christiane Roscher Michael Scherer-Lorenzen Bernhard Schmid Alexandra Weigelt 《Trends in ecology & evolution》2019,34(2):167-180
92.
Tatiana Dumitra Panaite Petru Alexandru Vlaicu Mariana Ropota Alexandru Radu Corbu Mihaela Saracila 《Archives of animal nutrition》2019,73(3):222-238
The aim of this study was to investigate the effects of simultaneous supplementation of laying hens with dietary sources of n-3 polyunsaturated fatty acids (PUFA) and carotenoids on egg quality, fatty acids and carotenoid profile of the egg yolk and on feed and yolk lipid peroxidation. A 6-week experiment was carried out with 53-week old laying hens (96 Tetra SL) assigned to a control and three treatment groups supplemented with 5% flaxseeds and different levels of dried tomato waste (DTW, 2.5%, 5.0% and 10.0%). Hens from the groups supplemented with 5% and 7.5% DTW had a significantly lower average daily feed intake and laying percentage as compared to the control. Increased doses of dietary DTW enhanced yolk Roche colour score in direct correlation with the enrichment of egg yolk in carotenoids but decreased their transfer efficiency from feed to egg. After 4 weeks, egg yolk from hens fed with 5% flaxseeds and 7.5% DTW had increased lutein and zeaxanthin levels (by 29% and 24%, respectively) and the colour score was 3.5 fold higher compared to the control group. As a result of the dietary supplementation with flaxseed, the n-3 fatty acid content was 3.1–3.7-fold higher in egg yolk compared with the control and the n-6/n-3 ratio decreased from 18.3 (control) to 4.1–5.4 in supplemented diets. Dietary supplementation with 5% DTW effectively prevented lipid oxidation of eggs enriched with n-3 PUFA, but the increase in DTW content depressed the absorption and deposition of n-3 PUFA in egg yolk. 相似文献
93.
94.
Vijay Singh Damodar Gupta Rajesh Arora Rajendra Prashad Tripathi Alexandru Almasan Roger M. Macklis 《PloS one》2014,9(11)
Background
The sensitivity of human Burkitt''s lymphoma cells to rituximab (Rtx) and tositumomab (Tst) was assessed on cells expressing different levels of CD20 on surface. Cells that harbor low CD20 levels may resists against therapeutics response to CD20-specific antibodies. We postulated that, radiation-induced modulation of CD20 surface levels may play a crucial and central role in determining the relative efficacy of rituximab and tositumomab in treating Burkitt''s lymphoma disease. Here, we examined the γ-radiation-induced CD20 expression in the Burkitt lymphoma cell line ‘Daudi’ and the relation of differential levels of CD20 with anti-CD20 mAbs mediated cell death.Methodology
In this study we examined kinetics of CD20 expression following sub lethal doses ofγ-radiation to Daudi cells and thereafter anti-CD20 mAbs (rituximab and tositumomab) were added in cell suspensions. The correlation of kinetics of CD20 expression and cells treated with anti-CD20 mAbs/or corresponding isotype Abs with special reference to changes in mitochondrial membrane potential and reactive oxygen species generation was also examined. Further, we also investigated the efficacy of anti-CD20 mAbs and possible induction of cell death in relation to levels of CD20 cell surface expression.Conclusion
This report provides evidence that CD20 expression can be induced by exposure of cells to γ-radiation. In addition, these findings demonstrated that the efficacy of anti-CD20 mAbs is dependent on the surface levels of CD20. Based on these findings, we hypothesized (i) irradiation just prior to immunotherapy may provide new treatment options even in aggressive B cell tumors, which are resistant to current therapies in vivo (ii) The efficacy of induction of apoptosis varies with type of monoclonal antibodies in vitro. 相似文献95.
A Bierhaus T Fleming S Stoyanov A Leffler A Babes C Neacsu SK Sauer M Eberhardt M Schnölzer F Lasischka WL Neuhuber TI Kichko I Konrade R Elvert W Mier V Pirags IK Lukic M Morcos T Dehmer N Rabbani PJ Thornalley D Edelstein C Nau J Forbes PM Humpert M Schwaninger D Ziegler DM Stern ME Cooper U Haberkorn M Brownlee PW Reeh PP Nawroth 《Nature medicine》2012,18(9):1445
96.
Rigazio S Lehto HR Tuunanen H Någren K Kankaanpaa M Simi C Borra R Naum AG Parkkola R Knuuti J Nuutila P Iozzo P 《American journal of physiology. Endocrinology and metabolism》2008,295(2):E413-E419
Lipolysis may regulate liver free fatty acid (FFA) uptake and triglyceride accumulation; both are potential causes of insulin resistance and liver damage. We evaluated whether 1) systemic FFA release is the major determinant of liver FFA uptake in fasting humans in vivo and 2) the beneficial metabolic effects of FFA lowering can be explained by a reduction in liver triglyceride content. Sixteen healthy subjects were subdivided in two groups of similar characteristics to undergo positron emission tomography with [(11)C]acetate and [(11)C]palmitate to quantify liver FFA metabolism (n = 8), or magnetic resonance spectroscopy (MRS) to measure hepatic fat content (n = 8), before and after the acute lowering of circulating FFAs by using the antilipolytic agent acipimox. MRS was again repeated after a 1-wk treatment period. Acipimox suppressed FFA levels while stimulating hepatic fractional extraction of FFAs (P < 0.05). As a result, fasting liver FFA uptake was decreased by 79% (P = 0.0002) in tight association with lipolysis (r = 0.996, P < 0.0001). The 1-wk treatment induced a significant improvement in systemic (+30%) and liver (+70%) insulin sensitivity (P < 0.05) and decreased circulating triglycerides (-20%, P = 0.06) and liver enzymes (ALT -20%, P = 0.03). No change in liver fat content was observed after either acute or sustained FFA suppression. We conclude that acute and sustained inhibitions of lipolysis and liver FFA uptake fail to deplete liver fat in healthy human subjects. Liver FFA uptake was decreased in proportion to FFA delivery. As a consequence, liver and systemic insulin sensitivity were improved, together with liver function, independently of changes in hepatic triglyceride accumulation. 相似文献
97.
98.
Hairpin-structured phosphorothioate oligodeoxyribonucleotides containing a singlet oxygen-sensitive linker in the loop were prepared. These compounds do not bind complementary nucleic acids in the dark. Upon irradiation with red light in the presence of chlorine e6 the linker within these compounds is cleaved and a single-stranded oligodeoxyribonucleotide is produced. The latter compound is an efficient binder of complementary nucleic acids. This is the first example of ‘caged’ phosphorothioate oligodeoxyribonucleotides, whose nucleic acid binding ability is triggered by red light. 相似文献
99.
Increasing the levels of CD20 expression in cells that harbor low CD20 levels may enhance their responsiveness to CD20-specific antibody therapies. Here, we examined the regulation of CD20 expression after treatment with 0.5-2.0 Gy X-irradiation and hydrogen peroxide (H(2)O(2)), in the presence or absence of known antioxidants, in the Burkitt lymphoma cell lines Daudi and Raji. Irradiation of cells enhanced cell-surface CD20 expression; the kinetics and extent of this change were cell-type specific and time-dependent. The kinetics of reactive oxygen species generation and changes in mitochondrial membrane potential after irradiation were also correlated with changes in CD20 expression. Raji and Daudi cells treated with H(2)O(2) showed a 2-to 2.5-fold increase in CD20 expression at 12 and 20 h, respectively. Buthionine sulfoximine, which depletes glutathione, also increased surface CD20, whereas antioxidants, such as PEG-catalase, PEG-SOD, vitamin C, and amifostine, decreased CD20 expression induced by radiation or H(2)O(2). The antioxidant-mediated decrease in CD20 expression induced by radiation or H(2)O(2) suggests a mechanism involving redox regulation. These results demonstrate the critical role of radiation-induced oxidative stress in CD20 expression and may have implications for defining and improving the efficacy of CD20-targeted antibody therapy and radioimmunotherapy. 相似文献
100.
Sato F Jin Z Schulmann K Wang J Greenwald BD Ito T Kan T Hamilton JP Yang J Paun B David S Olaru A Cheng Y Mori Y Abraham JM Yfantis HG Wu TT Fredericksen MB Wang KK Canto M Romero Y Feng Z Meltzer SJ 《PloS one》2008,3(4):e1890