全文获取类型
收费全文 | 978篇 |
免费 | 131篇 |
国内免费 | 77篇 |
专业分类
1186篇 |
出版年
2024年 | 3篇 |
2023年 | 10篇 |
2022年 | 26篇 |
2021年 | 40篇 |
2020年 | 33篇 |
2019年 | 39篇 |
2018年 | 38篇 |
2017年 | 40篇 |
2016年 | 47篇 |
2015年 | 60篇 |
2014年 | 66篇 |
2013年 | 60篇 |
2012年 | 97篇 |
2011年 | 79篇 |
2010年 | 47篇 |
2009年 | 47篇 |
2008年 | 46篇 |
2007年 | 26篇 |
2006年 | 45篇 |
2005年 | 32篇 |
2004年 | 38篇 |
2003年 | 48篇 |
2002年 | 34篇 |
2001年 | 35篇 |
2000年 | 25篇 |
1999年 | 25篇 |
1998年 | 12篇 |
1997年 | 10篇 |
1996年 | 11篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 14篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
排序方式: 共有1186条查询结果,搜索用时 7 毫秒
161.
小鼠子宫颈部位输卵管蛋白表达的初步研究 总被引:2,自引:0,他引:2
用RT-PCR及免疫印迹法检测证实小鼠子宫颈粘膜上皮细胞具表达输卵管蛋白的能力,宫颈部所获得的输卵管蛋白转录产物, 310到 714的405bp的cDNA片段经序列测定及blast比较表明与输卵管部位表达的输卵管蛋白完全一致(100%)。小鼠子宫颈输卵管蛋白在动情周期的表达波动情况与输卵管粘膜上皮的类似,其表达于小鼠动情期明显增加。Westernblot显示小鼠子宫颈提取物中存在两种不同分子量(60KD,30KD)的输卵管蛋白。原位杂交结果则提示子宫颈粘膜上皮细胞含丰富的输卵管蛋白mRNA信号。通过"原体中风"实验未发现输卵管蛋白在体外对精子活动有影响,其功能尚须进一步分析。 相似文献
162.
Tellurium@Ordered Macroporous Carbon Composite and Free‐Standing Tellurium Nanowire Mat as Cathode Materials for Rechargeable Lithium–Tellurium Batteries 下载免费PDF全文
163.
164.
Rong Li Xiao‐Ling Tang Shi‐Ying Miao Shu‐Dong Zong Lin‐Fang Wang 《Cell biochemistry and function》2009,27(5):264-268
Sperm associated antigen 8 (SPAG8), a testis‐specific protein produced during male germ cell differentiation, was isolated from a human testis expression library using antibodies found in the serum obtained from an infertile woman. It was found to have a close functional relationship with microtubules. In this study, we generated a stably expressing SPAG8 CHO‐K1 cell line. Immunofluorescence confocal microscopy showed that SPAG8 was concentrated at the microtubule‐organizing center (MTOC) during prophase. As the cells progressed into metaphase, it co‐localized with α‐tubulin on the spindle. In anaphase, it was detected on both astral microtubules and mid‐zone. Following cytokinesis, SPAG8 resumed its localization on the MTOC. Meanwhile, flow cytometry analysis found that SPAG8 prolonged the G2/M phase of CHO‐K1 cells stably expressing SPAG8. Furthermore, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay showed that SPAG8 inhibited the proliferation of the stable cells. SPAG8 might be involved in the regulation of cell cycle by changing the phosphorylation level of Tyr15 on cdc2. These results suggest that SPAG8 might play a role in cell division during spermatogenesis. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
165.
166.
Jingchao Zhang Shubin Li Tao Sun Yiwu Zong Weiwen Zhang Kun Zhao 《Environmental microbiology》2021,23(5):2692-2703
Labelling of Type IV pili (TFP) can greatly improve our understanding of the pivotal roles of TFP in a variety of bacterial activities including motility, surface sensing and DNA-uptake etc. Here we show a simple and switchable pili-labelling method by plasmid-based inducible replacement of PilA without genetic modification in bacterial genome employed by complicated methods. Using this method, we characterized pili morphology and twitching motility of Pseudomonas aeruginosa in details. More importantly, we demonstrate its application in studying the replenishment dynamics of pilin pool of P. aeruginosa. 相似文献
167.
Hu F Sun WW Zhao XT Cui ZJ Yang WX 《Biochemical and biophysical research communications》2008,369(4):989-993
Synoviocyte hyperplasia is critical for rheumatoid arthritis, therefore, potentially an important target for therapeutics. It was found in this work that a TRPV1 agonist capsaicin, and acidic solution (pH 5.5) induced increases in cytosolic calcium concentration ([Ca2+]c) and reactive oxygen species (ROS) production in synoviocytes isolated from a rat model of collagen-induced arthritis. The increases in both [Ca2+]c and ROS production were completely abolished in calcium-free buffer or by a TRPV1 antagonist capsazepine. Further experiments revealed that capsaicin and pH 5.5 solution caused mitochondrial membrane depolarization and reduction in cell viability; such effects were inhibited by capsazepine, or the NAD(P)H oxidase inhibitor diphenylene iodonium. Both capsaicin and pH 5.5 buffer induced apoptosis as shown by nuclear condensation and fragmentation. Furthermore, RT-PCR readily detected TRPV1 mRNA expression in the isolated synoviocytes. Taken together, these data indicated that TRPV1 activation triggered synoviocyte death by [Ca2+]c elevation, ROS production, and mitochondrial membrane depolarization. 相似文献
168.
Foo LC Allen NJ Bushong EA Ventura PB Chung WS Zhou L Cahoy JD Daneman R Zong H Ellisman MH Barres BA 《Neuron》2011,71(5):799-811
The inability to purify and culture astrocytes has long?hindered studies of their function. Whereas astrocyte progenitor cells can be cultured from neonatal brain, culture of mature astrocytes from postnatal brain has not been possible. Here, we report a new method to prospectively purify astrocytes by immunopanning. These astrocytes undergo apoptosis in culture, but vascular cells and HBEGF promote their survival in serum-free culture. We found that some developing astrocytes normally undergo apoptosis in?vivo and that the vast majority of astrocytes contact blood vessels, suggesting that?astrocytes are matched to blood vessels by competing for vascular-derived trophic factors such as HBEGF. Compared to traditional astrocyte cultures, the gene profiles of the cultured purified postnatal astrocytes much more closely resemble those of in?vivo astrocytes. Although these astrocytes strongly promote synapse formation and function, they do not secrete glutamate in response to stimulation. 相似文献
169.
Xin Zong Xiao Xiao Fu Jie Yuanzhi Cheng Mingliang Jin Yulong Yin Yizhen Wang 《中国科学:生命科学英文版》2021,(11):1988-1991
Dear editor,
Endotoxic shock usually results from infection-induced physiologic,pathologic,and biologic abnormalities (Singer et al.,2016).Undeniably,it is stil... 相似文献
170.
Two types of sulfated octyl tetra- to octaoligofucosides with different sulfation patterns were synthesized employing a combination of stepwise elongation and convergent strategies in which trichloroacetimidates and thioglycosides were selected as the glycosyl donors. 相似文献