全文获取类型
收费全文 | 713篇 |
免费 | 60篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 39篇 |
妇产科学 | 8篇 |
基础医学 | 77篇 |
口腔科学 | 20篇 |
临床医学 | 104篇 |
内科学 | 213篇 |
皮肤病学 | 6篇 |
神经病学 | 12篇 |
特种医学 | 166篇 |
外科学 | 39篇 |
综合类 | 19篇 |
预防医学 | 15篇 |
眼科学 | 6篇 |
药学 | 58篇 |
肿瘤学 | 28篇 |
出版年
2018年 | 12篇 |
2017年 | 8篇 |
2016年 | 6篇 |
2015年 | 9篇 |
2014年 | 17篇 |
2013年 | 11篇 |
2012年 | 12篇 |
2011年 | 9篇 |
2010年 | 17篇 |
2009年 | 31篇 |
2008年 | 8篇 |
2007年 | 29篇 |
2006年 | 12篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 12篇 |
1998年 | 52篇 |
1997年 | 45篇 |
1996年 | 38篇 |
1995年 | 30篇 |
1994年 | 24篇 |
1993年 | 33篇 |
1992年 | 8篇 |
1991年 | 14篇 |
1990年 | 13篇 |
1989年 | 34篇 |
1988年 | 21篇 |
1987年 | 22篇 |
1986年 | 13篇 |
1985年 | 21篇 |
1984年 | 14篇 |
1983年 | 16篇 |
1982年 | 14篇 |
1981年 | 20篇 |
1980年 | 23篇 |
1978年 | 11篇 |
1977年 | 8篇 |
1976年 | 9篇 |
1975年 | 8篇 |
1973年 | 5篇 |
1971年 | 6篇 |
1970年 | 10篇 |
1969年 | 8篇 |
1968年 | 15篇 |
1967年 | 7篇 |
1965年 | 5篇 |
排序方式: 共有812条查询结果,搜索用时 140 毫秒
1.
2.
3.
F. F. Snyder C. Dyer J. E. Seegmiller R. M. Goldblum G. C. Mills F. C. Schmalstieg 《Journal of inherited metabolic disease》1988,11(2):174-183
Summary The metabolism of adenosine and its effects on phosphoribosylpyrophosphate, PP-ribose-P, dependent nucleotide synthesis were studied using erythrocytes from patients with adenosine deaminase and hypoxanthine phosphoribosyltransferase deficiency as models. The phosphorylation of adenosine was progressively inhibited by concentrations of adenosine greater than 1 µmol L–1 for control and ADA deficient erythrocytes. There was essentially no initial rate of phosphorylation at 30 µmol L–1 adenosine. Adenosine, 1 µmol L–1, also caused a 60% reduction in PP-ribose-P concentration in ADA deficient erythrocytes. For HPRT deficient erythrocytes in which ADA activity was blocked by coformycin, 10 µmol L–1 inosine stimulated PP-ribose-P dependent nucleotide synthesis from adenine, whereas, 10 µmol L–1 adenosine inhibited nucleotide synthesis. These observations suggest that adenosine phosphorylation and PP-ribose-P dependent nucleotide synthesis are inhibited under conditions in which adenosine accumulates, such as in hereditary or pharmacologically induced ADA deficiency. 相似文献
4.
5.
Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
6.
7.
The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells. 相似文献
8.
9.
J A Schneider V Wong K Bradley J E Seegmiller 《The New England journal of medicine》1968,279(23):1253-1257
10.