全文获取类型
收费全文 | 10179篇 |
免费 | 927篇 |
国内免费 | 1612篇 |
出版年
2024年 | 37篇 |
2023年 | 162篇 |
2022年 | 300篇 |
2021年 | 552篇 |
2020年 | 420篇 |
2019年 | 520篇 |
2018年 | 518篇 |
2017年 | 372篇 |
2016年 | 454篇 |
2015年 | 750篇 |
2014年 | 801篇 |
2013年 | 808篇 |
2012年 | 1012篇 |
2011年 | 915篇 |
2010年 | 592篇 |
2009年 | 544篇 |
2008年 | 612篇 |
2007年 | 535篇 |
2006年 | 452篇 |
2005年 | 410篇 |
2004年 | 387篇 |
2003年 | 321篇 |
2002年 | 276篇 |
2001年 | 157篇 |
2000年 | 139篇 |
1999年 | 121篇 |
1998年 | 90篇 |
1997年 | 93篇 |
1996年 | 82篇 |
1995年 | 57篇 |
1994年 | 46篇 |
1993年 | 33篇 |
1992年 | 27篇 |
1991年 | 12篇 |
1990年 | 20篇 |
1989年 | 10篇 |
1988年 | 9篇 |
1987年 | 12篇 |
1986年 | 5篇 |
1985年 | 12篇 |
1984年 | 9篇 |
1983年 | 2篇 |
1982年 | 14篇 |
1979年 | 2篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1965年 | 1篇 |
1950年 | 5篇 |
1911年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 406 毫秒
61.
建立了一种改良的血清1,25-双羟胆钙化醇(1,25-Dihydroxycholecalciferol,DHCC)超微量放射受体检测(RRA)技术。完成了灵敏度、精密度、准确度、稳定性及特异性等技术指标。报告了我国健康青年血清DHCC正常值;检测了先天性佝偻病、青春期佝偻病病人及患肾性骨病奶牛等血清DHCC水平。 根据配体与受体相互结合的定量关系,建立了DHCCR(DHCC受体)检测技术。在游离与结合配基分离方面,除建立与比较了DCC(葡聚糖包埋的活性炭)及HAP(羟基磷灰石)方法外,还首次将IEF(等电聚焦电泳)应用于DHCCR分离技术。对佝偻病鸡小肠粘膜上皮细胞受体含量进行了检测并比较了鸡小肠、输卵管壳腺及肝组织DHCCR含量。 相似文献
62.
Schistosoma japonicum miracidia swim directed along a chemical gradient toward the snails Oncomelania hupensis and Biomphalaria glabrata, and they turn back when the concentration of attractive chemicals decreases. The host signal for this chemotactic response has a molecular weight of more than 30,000. When swimming miracidia encounter the surface of O. hupensis or agar containing O. hupensis snail-conditioned water (SCW) they perform the host-specific responses "contact with return," "repeated investigation," and "attachment," but they do not exhibit such behavior when encountering B. glabrata surface or agar containing B. glabrata SCW. Thus S. japonicum miracidia respond to different host signals when they approach snails than when they attach to snails. 相似文献
63.
冬小麦春化过程中低温诱导的与花芽分化相关的mRNA和蛋白质的合成 总被引:4,自引:0,他引:4
应用SDS电泳及高分辨双向电泳技术,分析了冬小麦经春化、脱春化及超期春化处理后茎类蛋白质组分的变化。发现52.5,38kD和16.2kD蛋白质与冬小麦开花诱导密切相关。mRNA体外翻译结果表明,春化作用中低温诱导与开花紧密相关的mRNA的出现有一定的顺序性。因此推测:春化诱导开花是低温导致某些特定基因表达的结果,而表达的调节主要发生在转录水平上。 相似文献
64.
Ai-Jie Xin Li Cheng Hua Diao Peng Wang Yi-Hua Gu Bin Wu Yan-Cheng Wu Guo-Wu Chen Shu-Min Zhou Shu-Juan Guo Hui-Juan Shi Sheng-Ce Tao 《Clinical proteomics》2014,11(1):10
It is well known that cell surface glycans or glycocalyx play important roles in sperm motility, maturation and fertilization. A comprehensive profile of the sperm surface glycans will greatly facilitate both basic research (sperm glycobiology) and clinical studies, such as diagnostics of infertility. As a group of natural glycan binders, lectin is an ideal tool for cell surface glycan profiling. However, because of the lack of effective technology, only a few lectins have been tested for lectin-sperm binding profiles. To address this challenge, we have developed a procedure for high-throughput probing of mammalian sperm with 91 lectins on lectin microarrays. Normal sperm from human, boar, bull, goat and rabbit were collected and analyzed on the lectin microarrays. Positive bindings of a set of ~50 lectins were observed for all the sperm of 5 species, which indicated a wide range of glycans are on the surface of mammalian sperm. Species specific lectin bindings were also observed. Clustering analysis revealed that the distances of the five species according to the lectin binding profiles are consistent with that of the genome sequence based phylogenetic tree except for rabbit. The procedure that we established in this study could be generally applicable for sperm from other species or defect sperm from the same species. We believe the lectin binding profiles of the mammalian sperm that we established in this study are valuable for both basic research and clinical studies. 相似文献
65.
66.
67.
68.
Hai‐Fan Yu Lian‐Wen Zheng Zhan‐Qing Yang Yu‐Si Wang Ji‐Cheng Huang Shu Liu Zhan‐Peng Yue Bin Guo 《Journal of cellular and molecular medicine》2020,24(12):7023-7033
Serpinb6b is a novel member of Serpinb family and found in germ and somatic cells of mouse gonads, but its physiological function in uterine decidualization remains unclear. The present study revealed that abundant Serpinb6b was noted in decidual cells, and advanced the proliferation and differentiation of stromal cells, indicating a creative role of Serpinb6b in uterine decidualization. Further analysis found that Serpinb6b modulated the expression of Mmp2 and Mmp9. Meanwhile, Serpinb6b was identified as a target of Bmp2 regulation in stromal differentiation. Treatment with rBmp2 resulted in an accumulation of intracellular cAMP level whose function in this differentiation program was mediated by Serpinb6b. Addition of PKA inhibitor H89 impeded the Bmp2 induction of Serpinb6b, whereas 8‐Br‐cAMP rescued the defect of Serpinb6b expression elicited by Bmp2 knock‐down. Attenuation of Serpinb6b greatly reduced the induction of constitutive Wnt4 activation on stromal cell differentiation. By contrast, overexpression of Serpinb6b prevented this inhibition of differentiation process by Wnt4 siRNA. Moreover, blockage of Wnt4 abrogated the up‐regulation of cAMP on Serpinb6b. Collectively, Serpinb6b mediates uterine decidualization via Mmp2/9 in response to Bmp2/cAMP/PKA/Wnt4 pathway. 相似文献
69.
Sayed Sifat Bin Nain Zulkar Khan Md. Shakil Ahmed Abdulla Faruq Tasmin Rubaia Adhikari Utpal Kumar 《International journal of peptide research and therapeutics》2020,26(4):2089-2107
International Journal of Peptide Research and Therapeutics - Lassa virus (LASV) is responsible for a type of acute viral haemorrhagic fever referred to as Lassa fever. Lack of adequate treatment... 相似文献
70.
Zhao Shan Li Zhiyong Xin Xiangdong Zhang Bei Jiang Xizhi Thomas Attaribo Charles Asakiya Zhang Lei Gui Zhongzheng 《International journal of peptide research and therapeutics》2020,26(4):1913-1921
International Journal of Peptide Research and Therapeutics - Silk fibroin is an excellent raw material for medical products as it shows remarkable biocompatibility, water-based processing, and... 相似文献