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   245993篇
  免费   21397篇
  国内免费   5142篇
耳鼻咽喉   4428篇
儿科学   5425篇
妇产科学   4151篇
基础医学   20241篇
口腔科学   8613篇
临床医学   22926篇
内科学   25852篇
皮肤病学   2867篇
神经病学   20055篇
特种医学   6202篇
外国民族医学   16篇
外科学   21863篇
综合类   36329篇
现状与发展   12篇
一般理论   25篇
预防医学   32041篇
眼科学   2216篇
药学   23048篇
  344篇
中国医学   26309篇
肿瘤学   9569篇
  2024年   887篇
  2023年   4813篇
  2022年   8542篇
  2021年   12376篇
  2020年   11875篇
  2019年   12835篇
  2018年   11675篇
  2017年   10246篇
  2016年   9186篇
  2015年   8555篇
  2014年   16568篇
  2013年   17768篇
  2012年   14605篇
  2011年   15740篇
  2010年   12651篇
  2009年   11267篇
  2008年   10693篇
  2007年   10527篇
  2006年   8917篇
  2005年   7451篇
  2004年   6212篇
  2003年   5636篇
  2002年   4341篇
  2001年   3570篇
  2000年   3145篇
  1999年   2607篇
  1998年   2135篇
  1997年   1905篇
  1996年   1529篇
  1995年   1452篇
  1994年   1315篇
  1993年   1183篇
  1992年   1101篇
  1991年   986篇
  1990年   879篇
  1989年   791篇
  1988年   756篇
  1987年   687篇
  1986年   620篇
  1985年   1913篇
  1984年   2177篇
  1983年   1371篇
  1982年   1792篇
  1981年   1260篇
  1980年   1078篇
  1979年   960篇
  1978年   797篇
  1977年   608篇
  1976年   744篇
  1975年   520篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
陈红亮 《中医学报》2016,(6):910-912
目的:观察理筋通督手法治疗颈性眩晕的临床疗效。方法:将120例颈性眩晕患者随机分成3组,理筋通督组、传统手法组及安慰剂组。理筋通督组采用理筋通督手法;传统手法组采用传统手法;安慰剂组口服维生素C。结果:理筋通督手法可显著减缓患者基底动脉舒张期最低血流速度(P0.05)。理筋通督组有效率为93.67%,传统手法组有效率为67.5%,安慰剂组有效率为17.5%,3组比较差异有统计学意义(P0.05),理筋通督组明显优于其他两组。结论:理筋通督手法治疗颈性眩晕临床疗效显著。  相似文献   
42.
43.
44.
45.
46.
ObjectivesPrior evidence suggests that sleep duration and sleep difficulties may be associated with cognitive function in old age, but little is known about the sleep–cognition association in late mid-life. Our aim was to examine the associations of accelerometer-based sleep duration as well as subjective sleep difficulties with different domains of cognitive function among aging workers.MethodsThe study population consisted of 289 participants (mean age 62.4 years, SD 1.02; 83% women) from the Finnish Retirement and Aging Study (FIREA). Sleep difficulties were measured using Jenkins Sleep Problem Scale (difficulties falling asleep, difficulties maintaining sleep, waking up too early in the morning, and nonrestorative sleep). Sleep duration was measured with wrist-worn accelerometer and self-report, and participants were divided into short (<7 h/night), mid-range (7–9 h/night) and long (≥9 h/night) sleepers. Participants underwent extensive cognitive testing covering three domains: (1) memory, (2) executive function, and (3) attention and information processing.ResultsGreater difficulties in waking up too early in the morning were associated with poorer executive function measured with Spatial Working Memory (SWM) test (p = 0.005). Additionally, nonrestorative sleep was associated with poorer executive function measured with Trail Making Test, B–A, (p = 0.036) and borderline significantly with lower SWM (p = 0.056). Compared to mid-range sleepers, long sleepers tended to have poorer cognitive function (all memory function tests and SWM), but the associations were not statistically significant due to small number of long sleepers.ConclusionsSubjective sleep difficulties may be linked to poorer executive function in a relatively healthy population of older workers in their 60 s. Thus, promoting good sleep quality may translate into better cognitive health in late mid-life.  相似文献   
47.
48.
49.
Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.

Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.

Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.

Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.

Trial registration: UMIN-CTR (UMIN000020288).  相似文献   

50.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  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