首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   263584篇
  免费   56680篇
  国内免费   12443篇
耳鼻咽喉   3370篇
儿科学   6399篇
妇产科学   3740篇
基础医学   35684篇
口腔科学   8205篇
临床医学   36750篇
内科学   49542篇
皮肤病学   8917篇
神经病学   21933篇
特种医学   8956篇
外国民族医学   76篇
外科学   33016篇
综合类   33108篇
现状与发展   45篇
一般理论   52篇
预防医学   17496篇
眼科学   6293篇
药学   25448篇
  164篇
中国医学   11861篇
肿瘤学   21652篇
  2024年   673篇
  2023年   2871篇
  2022年   7366篇
  2021年   10666篇
  2020年   11805篇
  2019年   16199篇
  2018年   16040篇
  2017年   16728篇
  2016年   17007篇
  2015年   19701篇
  2014年   21880篇
  2013年   21711篇
  2012年   18706篇
  2011年   19596篇
  2010年   18949篇
  2009年   13380篇
  2008年   12185篇
  2007年   11307篇
  2006年   10833篇
  2005年   10411篇
  2004年   7534篇
  2003年   7206篇
  2002年   6365篇
  2001年   5338篇
  2000年   4929篇
  1999年   4391篇
  1998年   2419篇
  1997年   2314篇
  1996年   1903篇
  1995年   1710篇
  1994年   1478篇
  1993年   930篇
  1992年   1321篇
  1991年   1100篇
  1990年   933篇
  1989年   804篇
  1988年   762篇
  1987年   678篇
  1986年   555篇
  1985年   440篇
  1984年   273篇
  1983年   213篇
  1982年   115篇
  1981年   122篇
  1980年   100篇
  1979年   141篇
  1978年   77篇
  1977年   71篇
  1976年   54篇
  1974年   61篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
4.
5.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
6.
7.

Context

Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.

Objectives/Methods

We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.

Results

Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.

Conclusion

Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months.  相似文献   
8.
9.
10.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号