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   273901篇
  免费   23361篇
  国内免费   16530篇
耳鼻咽喉   2350篇
儿科学   3428篇
妇产科学   5345篇
基础医学   32193篇
口腔科学   4806篇
临床医学   34832篇
内科学   44802篇
皮肤病学   3088篇
神经病学   15454篇
特种医学   9587篇
外国民族医学   115篇
外科学   30112篇
综合类   39061篇
现状与发展   56篇
一般理论   48篇
预防医学   17002篇
眼科学   7474篇
药学   27460篇
  175篇
中国医学   12590篇
肿瘤学   23814篇
  2024年   782篇
  2023年   3903篇
  2022年   9636篇
  2021年   12697篇
  2020年   9407篇
  2019年   8485篇
  2018年   9021篇
  2017年   7918篇
  2016年   7555篇
  2015年   11450篇
  2014年   14340篇
  2013年   13301篇
  2012年   19838篇
  2011年   21635篇
  2010年   13248篇
  2009年   10609篇
  2008年   14499篇
  2007年   14561篇
  2006年   14030篇
  2005年   14161篇
  2004年   9785篇
  2003年   8751篇
  2002年   7523篇
  2001年   6760篇
  2000年   7009篇
  1999年   7342篇
  1998年   4194篇
  1997年   4263篇
  1996年   3231篇
  1995年   3009篇
  1994年   2617篇
  1993年   1757篇
  1992年   2572篇
  1991年   2280篇
  1990年   1921篇
  1989年   1677篇
  1988年   1453篇
  1987年   1360篇
  1986年   1116篇
  1985年   876篇
  1984年   586篇
  1983年   458篇
  1982年   256篇
  1981年   240篇
  1980年   218篇
  1979年   274篇
  1978年   165篇
  1977年   129篇
  1976年   115篇
  1974年   123篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
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   
3.
4.
5.

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   
6.
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   
7.
8.
Finding appropriate soft-tissue to cover a wound located over the middle or distal portion of the foot can be challenging. A distally based sural fasciomusculocutaneous flap including the sural nerve and a midline cuff of the gastrocnemius muscle can be used for this purpose. This flap is designed on the proximal third of the posterior calf and is nourished in a retrograde manner by the lower peroneal septocutaneous perforators, through the vascular axis of the sural nerve to the musculocutaneous perforators of the gastrocnemius muscle. Between October of 2002 and January of 2004, this flap was applied in nine individuals, including four diabetic patients. The skin defects all resulted from trauma, osteomyelitis or chronic ulcer, and combined with bone or tendon exposure. One flap developed distal necrosis. The other flaps survived fully and provided good contour. In our series, diabetes mellitus seemed not to compromise the vascularity of the flap. The distally based sural fasciomusculocutaneous flap is very useful for lower limb reconstruction, particularly for the foot, because of its long vascular pedicle and the availability of the skin portion of the proximal calf based on direct branches between the musculocutaneous perforators and the neurovascular axis of the sural nerve. This is an important variant of the sural neurocutaneous flap and it appears to be a good alternative to free flaps for resurfacing the foot.  相似文献   
9.
公正的、客观的、完善的法律制度,是调整医患法律关系,规范医疗行为,保障医患双方合法权益的客观需要。随着我国法制建设的迅速发展,目前,患者越来越需要懂得依法维护自己的生命健康权利;医生越来越需要懂得依法进行诊疗,依法履行义务,依法维护自己的切身权利和利益;社会越来越需要有公正健全的法律制度。我国卫生法学领域的“新生代”正是在这种情况下应运而生的。各地涌现出一批兼有医学和法学双学历、勤勉好学、勇于探索、热衷于卫生法学研究的年轻人,将来必有建树。本刊《医与法》栏目就是他们及时发表睿见的一个园地,欢迎来稿。  相似文献   
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