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121.
不同生物药剂对稻水象甲的毒力、拒食活性及防效分析 总被引:2,自引:0,他引:2
【目的】防治稻水象甲的现有常规化学药剂的大量施用所引发的环境问题越发突出,而其生物药剂单一,加之天敌匮乏,故开展符合绿色生产标准的低毒、低残留、无污染生物药剂的筛选已成为稻水象甲防治工作所面临的首要任务。【方法】以越冬代稻水象甲成虫为试虫,采用室内点滴、田间喷雾等方法,对5种符合绿色生产标准药剂的毒力、拒食活性、防效及药后取食量等指标进行了测定和综合评价。【结果】室内生测方面:72 h后对处理稻水象甲成虫的室内毒力显著;此外,对试验前后的取食斑面积进行比较,发现药后各药剂拒食活性差异显著,均表现出较好的拒食作用。田间药效方面:除0.6%苦参碱AS外,其他药剂对稻水象甲均表现出较好的防效,100亿个孢子·m L~(-1)白僵菌OD、1.5%除虫菊素AS、7.5%鱼藤酮EC和6%乙基多杀菌素SC这4种药剂15 d的田间防效为51.24%~82.55%;3 d后各处理组田间新增取食斑数、取食长度均显著低于对照组。【结论】在绿色水稻生产中,100亿个孢子·m L~(-1)白僵菌OD、1.5%除虫菊素AS、7.5%鱼藤酮EC和6%乙基多杀菌素SC均具有较好的推广价值,可用于稻水象甲的防治。 相似文献
122.
Qu Z Karagueuzian HS Garfinkel A Weiss JN 《American journal of physiology. Heart and circulatory physiology》2004,286(4):H1310-H1321
The role of dynamic instabilities in the initiation of reentry in diseased (remodeled) hearts remains poorly explored. Using computer simulations, we studied the effects of altered Na(+) channel and cell coupling properties on the vulnerable window (VW) for reentry in simulated two-dimensional cardiac tissue with and without dynamic instabilities. We related the VW for reentry to effects on conduction velocity, action potential duration (APD), effective refractory period dispersion and restitution, and concordant and discordant APD alternans. We found the following: 1). reduced Na(+) current density and slowed recovery promoted postrepolarization refractoriness and enhanced concordant and discordant APD alternans, which increased the VW for reentry; 2). uniformly reduced cell coupling had little effect on cellular electrophysiological properties and the VW for reentry. However, randomly reduced cell coupling combined with decoupling promoted APD dispersion and alternans, which also increased the VW for reentry; 3). the combination of decreased Na(+) channel conductance, slowed Na(+) channel recovery, and cellular uncoupling synergistically increased the VW for reentry; and 4) the VW for reentry was greater when APD restitution slope was steep than when it was flat. In summary, altered Na(+) channel and cellular coupling properties increase vulnerability to reentrant arrhythmias. In remodeled hearts with altered Na(+) channel properties and cellular uncoupling, dynamic instabilities arising from electrical restitution exert important influences on the VW for reentry. 相似文献
123.
Rho‐kinase inhibitor Y‐27632 increases cellular proliferation and migration in human foreskin fibroblast cells 下载免费PDF全文
Juha Piltti Markku Varjosalo Chengjuan Qu Jukka Häyrinen Mikko J. Lammi 《Proteomics》2015,15(17):2953-2965
The idea of direct differentiation of somatic cells into other differentiated cell types has attracted a great interest recently. Rho‐kinase inhibitor Y‐27632 (ROCKi) is a potential drug molecule, which has been reported to support the gene expressions typical for the chondrocytes, thus restricting their phenotypic conversion to fibroblastic cells upon the cellular expansion. In this study, we have investigated the short‐term biological responses of ROCKi to human primary foreskin fibroblasts. The fibroblast cells were exposed to 1 and 10 μM ROCKi treatments. A proteomics analysis revealed expression changes of 56 proteins, and a further protein pathway analysis suggested their association with the cell morphology, the organization, and the increased cellular movement and the proliferation. These functional responses were confirmed by a Cell‐IQ time‐lapse imaging analysis. Rho‐kinase inhibitor treatment increased the cellular proliferation up to twofold during the first 12 h, and a wound model based migration assay showed 50% faster filling of the mechanically generated wound area. Additionally, significantly less vinculin‐associated focal adhesions were present in the ROCKi‐treated cells. Despite the marked changes in the cell behavior, ROCKi was not able to induce the expression of the chondrocyte‐specific genes, such as procollagen α1(II) and aggrecan. 相似文献
124.
Molecular docking and pharmacophore model approaches were used to characterise the binding features of four different series of Rho kinase (ROCK) inhibitors. Docking simulation of 20 inhibitors with ROCK was performed. The binding conformations and binding affinities of these inhibitors were obtained using AutoDock 4.0 software. The predicted binding affinities correlate well with the activities of these inhibitors (R 2 = 0.904). 3D pharmacophore models were generated for ROCK based on highly active inhibitors implemented in Catalyst 4.11 program. The best pharmacophore model consists of one hydrogen bond acceptor feature and two hydrophobic features, and they all seemed to be essential for inhibitors in terms of their binding activities. It is anticipated that the findings reported in this paper may provide very useful information for designing new ROCK inhibitors. 相似文献
125.
126.
Caspase-2 (casp-2) is the most conserved caspase across species, and is one of the initiator caspases activated by various stimuli. The casp-2 gene produces several alternative splicing isoforms. It is believed that the long isoform, casp-2L, promotes apoptosis, whereas the short isoform, casp-2S, inhibits apoptosis. The actual effect of casp-2S on apoptosis is still controversial, however, and the underlying mechanism for casp-2S-mediated apoptosis inhibition is unclear. Here, we analyzed the effects of casp-2S on DNA damage induced apoptosis through “gain-of-function” and “loss-of-function” strategies in ovarian cancer cell lines. We clearly demonstrated that the over-expression of casp-2S inhibited, and the knockdown of casp-2S promoted, the cisplatin-induced apoptosis of ovarian cancer cells. To explore the mechanism by which casp-2S mediates apoptosis inhibition, we analyzed the proteins which interact with casp-2S in cells by using immunoprecipitation (IP) and mass spectrometry. We have identified two cytoskeleton proteins, Fodrin and α-Actinin 4, which interact with FLAG-tagged casp-2S in HeLa cells and confirmed this interaction through reciprocal IP. We further demonstrated that casp-2S (i) is responsible for inhibiting DNA damage-induced cytoplasmic Fodrin cleavage independent of cellular p53 status, and (ii) prevents cisplatin-induced membrane blebbing. Taken together, our data suggests that casp-2S affects cellular apoptosis through its interaction with membrane-associated cytoskeletal Fodrin protein. 相似文献
127.
Min Wu Qi Shen Yong Yang Sheng Zhang Wen Qu Jing Chen Hongying Sun Shuqing Chen 《Journal of industrial microbiology & biotechnology》2013,40(6):589-599
Human serum albumin (HSA) and human parathyroid hormone (1-34) [PTH (1-34)] fusion protein [HSA/PTH (1-34)] is a promising long-acting form of PTH (1-34) for osteoporosis treatment. Secretory expression of intact HSA/PTH (1-34) in Pichia pastoris GS115 was accompanied by two degradation fragments, with molecular weights around 66 kDa, in addition to the well-known ~45 kDa HSA-truncated fragment, resulting in a low yield of intact protein. In this study, two internal cleavage sites were identified in the PTH (1-34) portion of the fusion protein by Western Blot analysis. To minimize proteolytic cleavages, several protease genes including PEP4 (encoding proteinase A), PRB1 (proteinase B) and seven YPSs genes (yapsin family members) were knocked out respectively by disruption of the individual genes and the selective combinations. Reduced degradation was observed by single disruption of either PEP4 gene or YPS1 gene, and the lowest level of degradation was observed in a pep4△yps1△ double disruptant. After 72 h of induction, more than 80 % of the HSA/PTH (1-34) secreted by the pep4△yps1△ double disruptant remained intact, in comparison to only 30 % with the wild-type strain. 相似文献
128.
Fatty acyl reductases (FARs) are key enzymes that participate in sex pheromone biosynthesis by reducing fatty acids to fatty alcohols. Lepidoptera typically harbor numerous FAR gene family members. Although FAR genes are involved in the biosynthesis of sex pheromones in moths, the key FAR gene of Spodoptera litura remains unclear. In this work, we predicted 30 FAR genes from the S. litura genome and identified a domain duplication within gene SlitFAR3, which exhibited high and preferential expression in the sexually mature female pheromone glands (PGs) and a rhythmic expression pattern during the scotophase of sex pheromone production. The molecular docking of SlitFAR3, as predicted using a 3D model, revealed a co-factor NADPH binding cavity and 2 substrate binding cavities. Functional expression in yeast cells combined with comprehensive gas chromatography indicated that the SlitFAR3 gene could produce fatty alcohol products. This study is the first to focus on the special phenomenon of FAR domain duplication, which will advance our understanding of biosynthesis-related genes from the perspective of evolutionary biology. 相似文献
129.
Wei Guo Mengxia Jin Zhaoxia Miao Kai Qu Xia Liu Peicheng Zhang Hailin Qin Haibo Zhu Yinghong Wang 《PloS one》2015,10(6)
2'', 3'', 5''-tri-O-acetyl-N6-(3-hydroxyphenyl) adenosine (also known as WS070117) is a new adenosine analog that displays anti-hyperlipidemic activity both in vitro and in vivo experiments as shown in many preliminary studies. Due to its new structure, little is known about the metabolism of WS070117. Hence, the in vivo metabolites of WS070117 in rat urine following oral administration were investigated. Identification of the metabolites was conducted using the combination of high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD), ion trap electrospray ionization-mass spectrometry (ESI-MS), and off-line microprobe nuclear magnetic resonance (NMR) measurements. Seven metabolites were obtained as pure compounds at the sub-milligram to milligram levels. Results of structure elucidation unambiguously revealed that the phase I metabolite, N6-(3-hydroxyphenyl) adenosine (M8), was a hydrolysate of WS070117 by hydrolysis on the three ester groups. N6-(3-hydr-oxyphenyl) adenine (M7), also one of the phase I metabolites, was the derivative of M8 by the loss of ribofuranose. In addition to two phase I metabolites, there were five phase II metabolites of WS070117 found in rat urine. 8-hydroxy-N6-(3-hydroxy-phenyl) adenosine (M6) was the product of M7 by hydrolysis at position 8. The other four were elucidated to be N6-(3-O-β-D-glucuronyphenyl) adenine (M2), N8-hydroxy-N6-(3-O-sulfophenyl) adenine (M3), N6-(3-O-β-D-glucuronyphenyl) adenosine (M4), and N6-(3-O- sulfophenyl) adenosine (M5). Phase II metabolic pathways were proven to consist of hydroxylation, glucuronidation and sulfation. This study provides new and valuable information on the metabolism of WS070117, and also demonstrates the HPLC/MS/off-line microprobe NMR approach as a robust means for rapid identification of metabolites. 相似文献
130.