全文获取类型
收费全文 | 36584篇 |
免费 | 2761篇 |
国内免费 | 138篇 |
专业分类
耳鼻咽喉 | 340篇 |
儿科学 | 843篇 |
妇产科学 | 692篇 |
基础医学 | 4905篇 |
口腔科学 | 964篇 |
临床医学 | 4435篇 |
内科学 | 7224篇 |
皮肤病学 | 367篇 |
神经病学 | 3883篇 |
特种医学 | 1375篇 |
外国民族医学 | 3篇 |
外科学 | 4968篇 |
综合类 | 537篇 |
现状与发展 | 1篇 |
一般理论 | 33篇 |
预防医学 | 2961篇 |
眼科学 | 708篇 |
药学 | 2919篇 |
中国医学 | 67篇 |
肿瘤学 | 2258篇 |
出版年
2023年 | 140篇 |
2022年 | 245篇 |
2021年 | 595篇 |
2020年 | 372篇 |
2019年 | 534篇 |
2018年 | 646篇 |
2017年 | 542篇 |
2016年 | 602篇 |
2015年 | 713篇 |
2014年 | 1070篇 |
2013年 | 1509篇 |
2012年 | 2329篇 |
2011年 | 2615篇 |
2010年 | 1427篇 |
2009年 | 1292篇 |
2008年 | 2316篇 |
2007年 | 2393篇 |
2006年 | 2241篇 |
2005年 | 2430篇 |
2004年 | 2168篇 |
2003年 | 2121篇 |
2002年 | 2021篇 |
2001年 | 528篇 |
2000年 | 487篇 |
1999年 | 559篇 |
1998年 | 530篇 |
1997年 | 405篇 |
1996年 | 391篇 |
1995年 | 358篇 |
1994年 | 301篇 |
1993年 | 280篇 |
1992年 | 327篇 |
1991年 | 286篇 |
1990年 | 278篇 |
1989年 | 271篇 |
1988年 | 265篇 |
1987年 | 258篇 |
1986年 | 244篇 |
1985年 | 287篇 |
1984年 | 274篇 |
1983年 | 245篇 |
1982年 | 274篇 |
1981年 | 246篇 |
1980年 | 255篇 |
1979年 | 177篇 |
1978年 | 183篇 |
1977年 | 176篇 |
1976年 | 141篇 |
1975年 | 121篇 |
1974年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Nidogen 1 (NID1) is a glycoprotein found in basement membranes involved in cross-linking collagen IV and laminin. The role of NID in breast cancer has only been evaluated in a small number of studies and the findings of these studies have been inconsistent. Our previous work revealed that highly tumorigenic murine mammary tumor cells express high levels of Nid1 while weakly tumorigenic mammary tumor cells express low levels of Nid1. To investigate Nid1, two stable knockdown lines were created, and Nid1 knockdown was confirmed at both the mRNA and protein level. Nid1 knockdown significantly reduced cell proliferation and migration/invasion and these reductions in proliferation and migration/invasion could be rescued by conditioned media containing NID1 protein. The reduced migration/invasion observed in the Nid1 knockdown cells was not associated with significant alterations in the epithelial gene Cdh1 or the mesenchymal genes Snai1, Snai2, Twist1, Twist2, Zeb1 and Zeb2. Therefore, suppression of Nid1 expression reduces proliferation and migration/invasion in claudin-low murine mammary tumor cells. 相似文献
2.
3.
4.
5.
ObjectivesTo fill an empirical gap in the literature by examining changes in quality of care measures occurring when multispecialty clinic systems were acquired by hospital-owned, vertically integrated health care delivery systems in the Twin Cities area.ConclusionsMoving a clinic system into a vertically integrated delivery system resulted in limited increases in quality of care indicators. Caution is warranted when the acquisition causes disruption in referral patterns. 相似文献
6.
7.
8.
Michael W. Manning Yi-Ju Li Dean Linder John C. Haney Yi-Hung Wu Mihai V. Podgoreanu Madhav Swaminathan Jacob N. Schroder Carmelo A. Milano Ian J. Welsby Mark Stafford-Smith Kamrouz Ghadimi 《Journal of cardiothoracic and vascular anesthesia》2021,35(5):1310-1318
- Download : Download high-res image (215KB)
- Download : Download full-size image
9.
Marleah Dean 《Health communication》2016,31(6):752-761
On May 14, 2013, Angelina Jolie disclosed she carries BRCA1, which means she has an 87% risk of developing breast cancer during her lifetime. Jolie decided to undergo a preventative bilateral mastectomy (PBM), reducing her risk to 5%. The purpose of this study was to analyze the type of information individuals are exposed to when using the Internet to search health information regarding Jolie’s decision. Qualitative content analysis revealed four main themes—information about genetics, information about a PBM, information about health care, and information about Jolie’s gender identity. Broadly, the identified websites mention Jolie’s high risk for developing cancer due to the genetic mutation BRCA1, describe a PBM occasionally noting reasons why she had this surgery and providing alternatives to the surgery, discuss issues related to health care services, costs, and insurances about Jolie’s health decision, and portray Jolie as a sexual icon, a partner to Brad Pitt, a mother of six children, and an inspirational humanitarian. The websites also depict Jolie’s health decision in positive, negative, and/or both ways. Discussion centers on how this actress’ health decision impacts the public. 相似文献
10.
Anne-Marie Selzler Veronica Moore Razanne Habash Lauren Ellerton Erica Lenton Roger Goldstein 《COPD》2020,17(4):452-461
Abstract The purpose of this study was to investigate the strength of the relationships between self-efficacy and (i) functional exercise capacity and (ii) physical activity in chronic obstructive pulmonary disease (COPD), and whether self-efficacy assessment type (i.e., COPD symptoms, exercise-task, exercise-barrier, general, falls) and physical activity assessment type (i.e., self-report vs. objective) are moderators. A systematic search of COPD and self-efficacy concepts was conducted using eight databases from inception to 23 January 2019. Studies were included if they provided correlation coefficients of the relationship between self-efficacy and functional exercise capacity or physical activity, were conducted in adults diagnosed with COPD, and were published in English-language journals. A total of 14 correlation coefficients were included in the self-efficacy and functional exercise capacity meta-analysis, and 16 in the self-efficacy and physical activity meta-analysis. Data were screened, reviewed, and extracted independently by two reviewers, with discrepancies resolved by a third reviewer. Stronger self-efficacy was associated with better functional exercise capacity (weighted r?=?0.38, 95%CI [0.25, 0.50]), and greater physical activity (weighted r?=?0.25, 95%CI [0.17, 0.34]). Exercise-task self-efficacy had the strongest relationship to functional exercise capacity (weighted r?=?0.64, 95% CI [0.51, 0.73]). For physical activity, the type of self-efficacy most strongly related was inconclusive. In COPD, self-efficacy has a relationship to functional exercise capacity and physical activity, the strength of which is influenced by the choice of self-efficacy measure. An understanding of these relationships will assist clinicians in selecting the self-efficacy measure most closely related to the outcome of interest. 相似文献