全文获取类型
收费全文 | 32342篇 |
免费 | 2730篇 |
国内免费 | 2351篇 |
出版年
2024年 | 52篇 |
2023年 | 415篇 |
2022年 | 457篇 |
2021年 | 1770篇 |
2020年 | 1117篇 |
2019年 | 1460篇 |
2018年 | 1397篇 |
2017年 | 1031篇 |
2016年 | 1383篇 |
2015年 | 2028篇 |
2014年 | 2386篇 |
2013年 | 2690篇 |
2012年 | 2979篇 |
2011年 | 2706篇 |
2010年 | 1634篇 |
2009年 | 1424篇 |
2008年 | 1658篇 |
2007年 | 1466篇 |
2006年 | 1290篇 |
2005年 | 1043篇 |
2004年 | 930篇 |
2003年 | 806篇 |
2002年 | 724篇 |
2001年 | 616篇 |
2000年 | 530篇 |
1999年 | 531篇 |
1998年 | 311篇 |
1997年 | 310篇 |
1996年 | 294篇 |
1995年 | 295篇 |
1994年 | 263篇 |
1993年 | 186篇 |
1992年 | 283篇 |
1991年 | 191篇 |
1990年 | 155篇 |
1989年 | 160篇 |
1988年 | 101篇 |
1987年 | 89篇 |
1986年 | 64篇 |
1985年 | 72篇 |
1984年 | 30篇 |
1983年 | 33篇 |
1982年 | 19篇 |
1981年 | 16篇 |
1980年 | 12篇 |
1979年 | 9篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 921 毫秒
991.
Duan Xianlan Zhao Lian Jin Wancun Xiao Qinxin Peng Yani Huang Gan Li Xia DaSilva-Arnold Sonia Yu Haibo Zhou Zhiguang 《Molecular biology reports》2020,47(10):7557-7566
Molecular Biology Reports - The main pathogenesis of type 1 diabetes mellitus (T1DM) is autoimmune-mediated apoptosis of pancreatic islet β cells. We sought to characterize the function of... 相似文献
992.
Ji Jie Xu Min-Xue Qian Tian-Yang Zhu Sheng-Ze Jiang Feng Liu Zhao-Xiu Xu Wei-Song Zhou Juan Xiao Ming-Bing 《Molecular biology reports》2020,47(8):6091-6103
Molecular Biology Reports - Cervical cancer is the leading cause of cancer-related death among women worldwide. Identifying an effective treatment with fewer side effects is imperative, because all... 相似文献
993.
Molecular Biology Reports - Chondrocytes are the sole cell type present within cartilage, and play pivotal roles in controlling the formation and composition of health cartilage. Chondrocytes... 相似文献
994.
Li Wanting Ye Anqi Ao Luyao Zhou Lin Yan Yunyi Hu Yahui Fang Weirong Li Yunman 《Neurochemical research》2020,45(10):2258-2277
Neurochemical Research - Stroke is the fifth leading cause of death worldwide and is a main cause of disability in adults. Neither currently marketed drugs nor commonly used treatments can promote... 相似文献
995.
Qian Wang Xiao-Ping Li Xi Zhou Chun-Fen Yang Zhu Zhu 《Journal of cellular biochemistry》2020,121(10):4108-4119
This study aimed to identify the association between lnc-LAMC2-1:1 polymorphism rs2147578 and the recurrence of ovary cancer, as well as to study the underlying mechanism of rs2147578 in ovary cancer. Real-time polymerase chain reaction, Western blot analysis, immunohistochemistry, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Logrank test, and Kaplan-Meier analysis were carried out to explore the role of rs2147578 in ovary cancer. No obvious difference was observed concerning all clinical characteristics among 90 patients genotyped as CC (N = 28), CG (N = 38), and GG (N = 24) in their rs2147578 polymorphism. In addition, the subjects carrying the CC genotype had longer recurrence-free survival time and showed a lower level of malignancy compared with those carrying CG and GG genotypes. Lnc-LAMC2-1:1 and miR-128 were lowly expressed in the CC group, while deleted in colorectal cancer (DCC) was highly expressed in the CC group. Furthermore, DCC was identified as a target gene of miR-128, and miR-128 mimics decreased the luciferase activity of cells cotransfected with wild-type DCC 3′-untranslated region. Lnc-LAMC2:1-1 directly targeted and affected miR-128 expression, and the G allele in lnc-LAMC2-1:1 rs2147578 upregulated miR-128 expression. Transfection with a miR-128 precursor evidently downregulated the expression of lnc-LAMC2-1:1, miR-128, and DCC expression, but did not affect the expression of ABCC5 and body mass index. Finally, miR-128 precursor promoted cell proliferation and inhibited cell apoptosis. Compared with lnc-LAMC2-1:1 rs2147578C allele, the G allele increases the risk of ovarian cancer by reducing the binding between lnc-LAMC2-1:1 and miR-128-3p, which in turn further decreases the expression of DCC and inhibits cell apoptosis. 相似文献
996.
997.
Zhou Peilu Khan Rayyan Li Qiyao Liu Guangliang Xu Na Yang Yinju Wang Yi Wang Shusheng Chen Aiguo 《Plant Molecular Biology Reporter》2020,38(1):1-13
Plant Molecular Biology Reporter - Low temperature is among the most significant abiotic stresses restricting geographical distribution of plants and reducing crop productivity. However, the... 相似文献
998.
Experiments that longitudinally collect RNA sequencing (RNA-seq) data can provide transformative insights in biology research by revealing the dynamic patterns of genes. Such experiments create a great demand for new analytic approaches to identify differentially expressed (DE) genes based on large-scale time-course count data. Existing methods, however, are suboptimal with respect to power and may lack theoretical justification. Furthermore, most existing tests are designed to distinguish among conditions based on overall differential patterns across time, though in practice, a variety of composite hypotheses are of more scientific interest. Finally, some current methods may fail to control the false discovery rate. In this paper, we propose a new model and testing procedure to address the above issues simultaneously. Specifically, conditional on a latent Gaussian mixture with evolving means, we model the data by negative binomial distributions. Motivated by Storey (2007) and Hwang and Liu (2010), we introduce a general testing framework based on the proposed model and show that the proposed test enjoys the optimality property of maximum average power. The test allows not only identification of traditional DE genes but also testing of a variety of composite hypotheses of biological interest. We establish the identifiability of the proposed model, implement the proposed method via efficient algorithms, and demonstrate its good performance via simulation studies. The procedure reveals interesting biological insights, when applied to data from an experiment that examines the effect of varying light environments on the fundamental physiology of the marine diatom Phaeodactylum tricornutum. 相似文献
999.
Recurrent event data are commonly encountered in biomedical studies. In many situations, they are subject to an informative terminal event, for example, death. Joint modeling of recurrent and terminal events has attracted substantial recent research interests. On the other hand, there may exist a large number of covariates in such data. How to conduct variable selection for joint frailty proportional hazards models has become a challenge in practical data analysis. We tackle this issue on the basis of the “minimum approximated information criterion” method. The proposed method can be conveniently implemented in SAS Proc NLMIXED for commonly used frailty distributions. Its finite-sample behavior is evaluated through simulation studies. We apply the proposed method to model recurrent opportunistic diseases in the presence of death in an AIDS study. 相似文献
1000.