全文获取类型
收费全文 | 137862篇 |
免费 | 9616篇 |
国内免费 | 630篇 |
专业分类
耳鼻咽喉 | 1671篇 |
儿科学 | 3469篇 |
妇产科学 | 2520篇 |
基础医学 | 17591篇 |
口腔科学 | 2912篇 |
临床医学 | 13594篇 |
内科学 | 28374篇 |
皮肤病学 | 1771篇 |
神经病学 | 12123篇 |
特种医学 | 5508篇 |
外科学 | 22105篇 |
综合类 | 1991篇 |
现状与发展 | 1篇 |
一般理论 | 174篇 |
预防医学 | 12559篇 |
眼科学 | 2934篇 |
药学 | 9730篇 |
2篇 | |
中国医学 | 179篇 |
肿瘤学 | 8900篇 |
出版年
2023年 | 678篇 |
2022年 | 1057篇 |
2021年 | 2599篇 |
2020年 | 1481篇 |
2019年 | 2416篇 |
2018年 | 2951篇 |
2017年 | 2139篇 |
2016年 | 2251篇 |
2015年 | 2746篇 |
2014年 | 4060篇 |
2013年 | 6119篇 |
2012年 | 8945篇 |
2011年 | 9526篇 |
2010年 | 5302篇 |
2009年 | 4854篇 |
2008年 | 8473篇 |
2007年 | 9071篇 |
2006年 | 8632篇 |
2005年 | 8798篇 |
2004年 | 8459篇 |
2003年 | 7961篇 |
2002年 | 7761篇 |
2001年 | 1325篇 |
2000年 | 1099篇 |
1999年 | 1438篇 |
1998年 | 1646篇 |
1997年 | 1318篇 |
1996年 | 1269篇 |
1995年 | 1245篇 |
1994年 | 1042篇 |
1993年 | 1015篇 |
1992年 | 885篇 |
1991年 | 905篇 |
1990年 | 799篇 |
1989年 | 776篇 |
1988年 | 786篇 |
1987年 | 774篇 |
1986年 | 787篇 |
1985年 | 869篇 |
1984年 | 947篇 |
1983年 | 881篇 |
1982年 | 1150篇 |
1981年 | 1172篇 |
1980年 | 976篇 |
1979年 | 652篇 |
1978年 | 689篇 |
1977年 | 613篇 |
1976年 | 534篇 |
1975年 | 480篇 |
1974年 | 492篇 |
排序方式: 共有10000条查询结果,搜索用时 34 毫秒
91.
James E. Vogel MD 《Aesthetic surgery journal / the American Society for Aesthetic Plastic surgery》2004,24(6):561-564
The hairline and frontal hair volume are frequently overlooked aspects of attractive facial proportion and overall facial aesthetics. The author contends that patient benefit from hair restoration surgery is significant, and these procedures should be routinely considered as part of a complete facial rejuvenation. 相似文献
92.
93.
Ross W. James Peter A Howat K. John Fisher 《Australian and New Zealand journal of public health》1987,11(1):54-61
Health education campaigns which utilise the mass media generally employ advertising techniques. Television and print media are considered more influential, with radio being primarily used for awareness raising and campaign support messages. There is relatively little research into the effectiveness of radio talkback programs in promoting health or reducing illness. This paper argues a case for health and welfare professionals to utilise talkback radio as part of their health promotion activities. 相似文献
94.
James W Van Huysse 《Pathophysiology》2007,14(3-4):213-220
An endogenous ouabain-like substance (OLS) plays a critical role in the etiology of experimental models of human hypertension induced by a high salt diet. Early on, evidence for a role of this Na, K-ATPase inhibitor in blood pressure regulation was provided mainly by correlations of blood pressure with the levels of circulating Na, K-ATPase inhibitor. However, over the past decade, numerous studies have shown that endogenous Na pump inhibitors in the brain mediate salt-dependent hypertension in a variety of experimental models, including Dahl salt-sensitive (Dahl-S) and spontaneously hypertensive (SHR) rats on a high-salt diet. Other forms of hypertension that are known to be mediated by endogenous ouabain-like substances include steroid/salt- (e.g., DOCA-salt) and ACTH-induced hypertension. Even when exogenous ouabain is peripherally administered and/or the plasma ouabain/OLS level is increased in rats, the resulting hypertension is of CNS origin. After peripheral ouabain administration, ouabain levels increase in the plasma and the inhibitor subsequently accumulates in the brain. The ensuing hypertension is abolished by the intracerebroventricular (icv) administration of an anti-ouabain antibody (but not by the same antibody dose given iv), by discrete excitotoxic lesions in the brain or by ganglionic blockade, demonstrating that the response is neurally mediated. The pressor response to stimuli that increase the brain OLS (high salt diet, icv sodium) or to icv ouabain is abolished by icv losartan, demonstrating that the brain OLS activates the brain renin-angiotensin system (RAS) downstream. There are three isoforms of the catalytic alpha subunit of the Na, K-ATPase in the brain and cardiovascular system (alpha1, alpha2 and alpha3), but it is not known which brain isoform(s) mediate the hypertensive effects of circulating/CNS ouabain. Preliminary studies in gene-targeted mice suggest that the alpha2 isoform plays a critical role. 相似文献
95.
96.
97.
98.
99.
100.
James Edward Paul Elizabeth Ling Carlos Lalonde Lehana Thabane 《Journal canadien d'anesthésie》2007,54(10):799-810
PURPOSE: To determine if deliberate hypotension decreases blood loss and transfusion requirements in patients undergoing orthopedic surgery, a systematic review of all randomized trials addressing this issue was undertaken. METHODS: Electronic databases, citations lists and review articles were searched for potential articles. Relevant articles met the following inclusion criteria: English language, humans undergoing orthopedic surgery, deliberate hypotension used by any method, intraoperative blood loss measured as an outcome, and the trial methodology being randomized and controlled. Four outcomes were analyzed, including estimated blood loss, blood transfused, surgery duration, and quality of the surgical field. For all analyses, the random-effects model was used. RESULTS: Seventeen articles met the inclusion criteria. The surgeries studied included total hip arthroplasty (seven), orthognathic surgery (eight), total knee arthroplasty (one) and spinal fusion (one). A total of 636 patients were randomized across all studies. For blood loss, the overall weighted mean difference favoured treatment, with a savings of about 287 mL of blood [95% confidence interval (CI): -447, -127]. The mean differences also showed a statistically significant benefit for deliberate hypotension in reducing transfusion requirements (-667 mL of blood transfused; 95% CI: -963, -370). Deliberate hypotension was not shown to reduce the duration of surgery (-1.9 min of surgery; 95% CI: -7.2, 3.5) or improve surgical conditions (surgical field quality rating -0.5; 95% CI: -1.1, 0.2). CONCLUSION: This review provides some support for the use of deliberate hypotension in reducing blood loss and transfusion requirements in orthopedic surgery, but these results are tempered by the small sample sizes and poor methodological quality of published studies. 相似文献