全文获取类型
收费全文 | 34600篇 |
免费 | 2844篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 286篇 |
儿科学 | 1304篇 |
妇产科学 | 1065篇 |
基础医学 | 4410篇 |
口腔科学 | 582篇 |
临床医学 | 5798篇 |
内科学 | 6299篇 |
皮肤病学 | 509篇 |
神经病学 | 3317篇 |
特种医学 | 697篇 |
外国民族医学 | 1篇 |
外科学 | 3362篇 |
综合类 | 422篇 |
一般理论 | 68篇 |
预防医学 | 4307篇 |
眼科学 | 483篇 |
药学 | 1895篇 |
1篇 | |
中国医学 | 32篇 |
肿瘤学 | 2686篇 |
出版年
2023年 | 167篇 |
2022年 | 238篇 |
2021年 | 573篇 |
2020年 | 480篇 |
2019年 | 798篇 |
2018年 | 843篇 |
2017年 | 628篇 |
2016年 | 780篇 |
2015年 | 819篇 |
2014年 | 1065篇 |
2013年 | 1618篇 |
2012年 | 2273篇 |
2011年 | 2306篇 |
2010年 | 1284篇 |
2009年 | 1181篇 |
2008年 | 2168篇 |
2007年 | 2329篇 |
2006年 | 2305篇 |
2005年 | 2233篇 |
2004年 | 2101篇 |
2003年 | 2039篇 |
2002年 | 1916篇 |
2001年 | 488篇 |
2000年 | 457篇 |
1999年 | 449篇 |
1998年 | 487篇 |
1997年 | 367篇 |
1996年 | 350篇 |
1995年 | 348篇 |
1994年 | 286篇 |
1993年 | 271篇 |
1992年 | 257篇 |
1991年 | 232篇 |
1990年 | 219篇 |
1989年 | 240篇 |
1988年 | 189篇 |
1987年 | 167篇 |
1986年 | 196篇 |
1985年 | 195篇 |
1984年 | 186篇 |
1983年 | 169篇 |
1982年 | 175篇 |
1981年 | 165篇 |
1980年 | 168篇 |
1979年 | 117篇 |
1978年 | 106篇 |
1977年 | 88篇 |
1976年 | 96篇 |
1975年 | 87篇 |
1974年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
21.
This is the third and final part of a series of articles that report the findings of a study that investigated the effects of a summer externship program on the transition into a professional role among nurses who participated in a summer nurse externship program at an acute care pediatric hospital. Specifically, this article reports the retention and recruitment benefits of a summer nurse externship program for the institution from 1998 through 2003. A total of 153 externs out of the 193 (79.0%) assumed a registered nurse position at the institution, and 77% remained in that role for 12 months. Overall, the nurse extern program for this institution appeared to be an effective recruitment and retention strategy that is on par with the institution and national data for retention and turnover data. 相似文献
22.
Sally Ann Lederman 《Journal of human lactation》2006,22(4):387; author reply 387-387; author reply 388
23.
24.
25.
26.
Michael K. Gardner Elaine Clark Mary Ann C. Bowman Patrick J. Miller 《Alcoholism, clinical and experimental research》1989,13(4):508-511
This study investigated analogical reasoning abilities of alcoholics who had been abstinent from alcohol for at least 1 year. Their performance was compared to that of nonalcoholic controls matched as a group for education, age, and gender. Solution times and error rates were modeled using a regression model. Results showed a nonsignificant trend for alcoholics to be faster, but more error prone, than controls. The same componential model applied to both groups, and fit them equally well. Although differences have been found in analogical reasoning ability between controls and alcoholics immediately following detoxification, we find no evidence of differences after extended periods of sobriety. 相似文献
27.
28.
Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia. 相似文献
29.
30.