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   355896篇
  免费   27017篇
  国内免费   15648篇
耳鼻咽喉   3710篇
儿科学   5972篇
妇产科学   8916篇
基础医学   45877篇
口腔科学   7644篇
临床医学   39789篇
内科学   60503篇
皮肤病学   5149篇
神经病学   21259篇
特种医学   12423篇
外国民族医学   99篇
外科学   42755篇
综合类   38594篇
现状与发展   48篇
一般理论   78篇
预防医学   23561篇
眼科学   9399篇
药学   33892篇
  164篇
中国医学   11615篇
肿瘤学   27114篇
  2023年   3765篇
  2022年   9139篇
  2021年   12345篇
  2020年   8900篇
  2019年   8546篇
  2018年   9476篇
  2017年   8040篇
  2016年   7766篇
  2015年   11413篇
  2014年   14437篇
  2013年   14167篇
  2012年   20851篇
  2011年   22796篇
  2010年   13887篇
  2009年   11293篇
  2008年   15947篇
  2007年   16227篇
  2006年   15772篇
  2005年   15487篇
  2004年   11476篇
  2003年   10329篇
  2002年   9156篇
  2001年   12288篇
  2000年   12626篇
  1999年   11754篇
  1998年   5323篇
  1997年   4932篇
  1996年   3684篇
  1995年   3414篇
  1994年   2991篇
  1993年   2249篇
  1992年   5839篇
  1991年   5644篇
  1990年   5086篇
  1989年   4840篇
  1988年   4541篇
  1987年   4279篇
  1986年   3900篇
  1985年   3589篇
  1984年   2457篇
  1983年   2113篇
  1982年   1175篇
  1979年   2133篇
  1978年   1322篇
  1975年   1276篇
  1974年   1474篇
  1973年   1507篇
  1972年   1430篇
  1971年   1323篇
  1970年   1206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.
6.

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   
7.
Abstract

Background: This study aims to compare the effectiveness of inhaled prostacyclin or its analoguesversus nitric oxide (NO) in treating pulmonary hypertension (PH) after cardiac or pulmonary surgery remains unclear.

Methods: PubMed, Cochrane, and Embase databases were searched for literature published prior to December 2019 using the following keywords: inhaled, nitric oxide, prostacyclin, iloprost, treprostinil, epoprostenol, Tyvaso, flolan, and pulmonary hypertension. Randomized controlled trials and multiple-armed prospective studies that evaluated inhaled NO versus prostacyclin (or analogues) in patients for perioperative and/or postoperative PH after either cardiac or pulmonary surgery were included. Retrospective studies, reviews, letters, comments, editorials, and case reports were excluded.

Results: Seven studies with a total of 195 patients were included. No difference in the improvement of mean pulmonary arterial pressure (pooled difference in mean change= ?0.10, 95% CI: ?3.98 to 3.78, p?=?.959) or pulmonary vascular resistance (pooled standardized difference in mean change= ?0.27, 95% CI: ?0.60 to 0.05, p?=?.099) were found between the two treatments. Similarly, no difference was found in other outcomes between the two treatments or subgroup analysis.

Conclusions: Inhaled prostacyclin (or analogues) was comparable to inhaled NO in treating PH after cardiac or pulmonary surgery.
  • Key messages
  • This study compared the efficacy of inhaled prostacyclin or its analogues versus inhaled NO to treat PH after surgery. The two types of agent exhibited similar efficacy in managing MPAP, PVR, heart rate, and cardiac output was observed.

  • Inhaled prostacyclin may serve as an alternative treatment option for PH after cardiac or pulmonary surgery.

  相似文献   
8.
Abstract

Purpose: We examined underlying psychosocial processes of a behavioral treatment for urinary incontinence (UI) of prostate cancer survivors.

Design: Secondary analysis of data collected from a clinical trial.

Sample: Two hundred forty-four prostate cancer survivors who participated in a clinical trial of behavioral intervention to UI as intervention or control subjects.

Methods: The participants had a 3-month behavioral intervention or usual care and were followed up for an additional 3?months. They were assessed at baseline, 3, and 6?months. Latent growth curve models were performed to examine trajectories of each study variable and relationships among the variables.

Findings: Increasing self-efficacy and social support were significantly and independently associated with more reduction of urinary leakage frequency over time.

Implications for psychosocial oncology: Providing problem-solving skills and social support, including peer support, are essential for empowering patients to reduce UI.  相似文献   
9.
10.
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