全文获取类型
收费全文 | 1493篇 |
免费 | 218篇 |
出版年
2021年 | 15篇 |
2019年 | 16篇 |
2018年 | 17篇 |
2016年 | 27篇 |
2015年 | 33篇 |
2014年 | 43篇 |
2013年 | 32篇 |
2012年 | 54篇 |
2011年 | 49篇 |
2010年 | 37篇 |
2009年 | 35篇 |
2008年 | 55篇 |
2007年 | 49篇 |
2006年 | 63篇 |
2005年 | 61篇 |
2004年 | 56篇 |
2003年 | 55篇 |
2002年 | 51篇 |
2001年 | 43篇 |
2000年 | 39篇 |
1999年 | 51篇 |
1998年 | 26篇 |
1997年 | 21篇 |
1996年 | 15篇 |
1995年 | 19篇 |
1994年 | 14篇 |
1993年 | 24篇 |
1992年 | 50篇 |
1991年 | 38篇 |
1990年 | 34篇 |
1989年 | 37篇 |
1988年 | 33篇 |
1987年 | 43篇 |
1986年 | 29篇 |
1985年 | 26篇 |
1984年 | 28篇 |
1983年 | 22篇 |
1982年 | 17篇 |
1981年 | 22篇 |
1980年 | 13篇 |
1979年 | 37篇 |
1978年 | 29篇 |
1977年 | 22篇 |
1975年 | 15篇 |
1974年 | 14篇 |
1973年 | 14篇 |
1972年 | 16篇 |
1971年 | 15篇 |
1970年 | 19篇 |
1968年 | 19篇 |
排序方式: 共有1711条查询结果,搜索用时 19 毫秒
101.
102.
A lymphocyte population of common marmosets (Callithrix jacchus) was identified by rosette formation with African green monkey erythrocytes; the rosette-forming cells appeared to be T lymphocytes, as approximately 62% of circulating lymphocytes and 85% of thymus cells formed rosettes with African green monkey erythrocytes. In addition, common marmoset lymphoid cells carrying T-lymphotropic Herpesvirus saimiri or Herpesvirus ateles formed rosettes with African green monkey erythrocytes and treatment of common marmoset circulating lymphocytes with an anti-T cell serum and complement (C′) eliminated rosette-forming cells. Common marmoset T lymphocytes apparently carry a surface receptor for African green monkey erythrocytes, but unlike humans and other closely related nonhuman primates, T lymphocytes of common marmosets fail to form rosettes with sheep erythrocytes. 相似文献
103.
104.
105.
106.
Structural analysis of basal bodies of the isolated oral apparatus of Tetrahymena pyriformis 总被引:7,自引:0,他引:7
J Wolfe 《Journal of cell science》1970,6(3):679-700
107.
Coral Reefs - Structural complexity provided by the living coral reef framework is the basis of the rich and dynamic biodiversity in coral reefs. In many cases today, the reduction in habitat... 相似文献
108.
109.
Edoardo Francini Fang-Shu Ou Stefano Lazzi Roberto Petrioli Andrea G. Multari Guido Pesola Luciana Messuti Elena Colombo Virginia Livellara Serena Bazzurri Sara Cherri Salvatora T. Miano Eric G. Wolfe Steven R. Alberts Joleen M. Hubbard Harry H. Yoon Guido Francini 《Translational oncology》2021,14(2)
BackgroundHigh tumor infiltrating lymphocytes (TILs) density was previously shown to be associated with favorable prognosis for patients with colon cancer (CC). However, the impact of TILs on overall survival (OS) of stage II CC patients who received adjuvant chemotherapy (ADJ) or not (no-ADJ) is unknown. We assessed the prognostic value of CD3+ TILs in stage II CC patients according to whether they had ADJ or not.MethodsPatients treated with curative surgery for stage II CC (2002–2013) were selected from the Santa Maria alle Scotte Hospital registry. TILs at the invasive front, center of tumor, and stroma were determined by immunohistochemistry and manually quantified as the rate of TILs/total tissue areas. High TILs (H-TILs) was defined as >20%. Patients were categorized as high or low TILs (L-TILs) and ADJ or no-ADJ.ResultsOf the 678 patients included, 137 (20%) received ADJ and 541 (80%) did not. The distribution of the 4 groups were: 16% (L-TIL/ADJ), 64% (L-TIL/no-ADJ), 5% (H-TIL/ADJ), 15% (H-TIL/no-ADJ). Compared to H-TILs/no-ADJ, ADJ patients showed a significantly increased OS (P<.01) regardless of the TILs rate whereas L-TILs/no-ADJ had significantly decreased OS and higher risk of death (HR=1.41; 95% CI, 1.06–1.88; P<.0001). On multivariable analysis, the unfavorable prognostic value of L-TILs (vs. H-TILs) for no-ADJ patients was confirmed (HR=1.36; 95% CI 1.02, 1.82; P=.0373).ConclusionLow CD3+ TILs rate was associated with shorter OS in those with stage II colon cancer who did not receive adjuvant therapy. Low CD3+ TILs could be considered an additional risk factor for still ADJ-untreated stage II CC patients, which could facilitate clinical decision making. 相似文献
110.
Katie J. Wolfe Hong Yu Ren Philipp Trepte Douglas M. Cyr 《Molecular biology of the cell》2013,24(23):3588-3602
Conformational diseases are associated with the conversion of normal proteins into aggregation-prone toxic conformers with structures similar to that of β-amyloid. Spatial distribution of amyloid-like proteins into intracellular quality control centers can be beneficial, but cellular mechanisms for protective aggregation remain unclear. We used a high-copy suppressor screen in yeast to identify roles for the Hsp70 system in spatial organization of toxic polyglutamine-expanded Huntingtin (Huntingtin with 103Q glutamine stretch [Htt103Q]) into benign assemblies. Under toxic conditions, Htt103Q accumulates in unassembled states and speckled cytosolic foci. Subtle modulation of Sti1 activity reciprocally affects Htt toxicity and the packaging of Htt103Q into foci. Loss of Sti1 exacerbates Htt toxicity and hinders foci formation, whereas elevation of Sti1 suppresses Htt toxicity while organizing small Htt103Q foci into larger assemblies. Sti1 also suppresses cytotoxicity of the glutamine-rich yeast prion [RNQ+] while reorganizing speckled Rnq1–monomeric red fluorescent protein into distinct foci. Sti1-inducible foci are perinuclear and contain proteins that are bound by the amyloid indicator dye thioflavin-T. Sti1 is an Hsp70 cochaperone that regulates the spatial organization of amyloid-like proteins in the cytosol and thereby buffers proteotoxicity caused by amyloid-like proteins. 相似文献