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   80652篇
  免费   5861篇
  国内免费   416篇
耳鼻咽喉   797篇
儿科学   2042篇
妇产科学   1830篇
基础医学   10161篇
口腔科学   1816篇
临床医学   8280篇
内科学   17995篇
皮肤病学   979篇
神经病学   6615篇
特种医学   2496篇
外国民族医学   3篇
外科学   12239篇
综合类   1214篇
现状与发展   1篇
一般理论   135篇
预防医学   7307篇
眼科学   2178篇
药学   5566篇
中国医学   170篇
肿瘤学   5105篇
  2023年   381篇
  2022年   392篇
  2021年   1603篇
  2020年   1005篇
  2019年   1399篇
  2018年   1745篇
  2017年   1199篇
  2016年   1335篇
  2015年   1548篇
  2014年   2402篇
  2013年   3644篇
  2012年   5094篇
  2011年   5606篇
  2010年   3148篇
  2009年   2839篇
  2008年   5159篇
  2007年   5532篇
  2006年   5184篇
  2005年   5318篇
  2004年   5008篇
  2003年   4532篇
  2002年   4386篇
  2001年   937篇
  2000年   782篇
  1999年   932篇
  1998年   917篇
  1997年   729篇
  1996年   603篇
  1995年   601篇
  1994年   543篇
  1993年   522篇
  1992年   616篇
  1991年   581篇
  1990年   488篇
  1989年   512篇
  1988年   454篇
  1987年   418篇
  1986年   387篇
  1985年   463篇
  1984年   478篇
  1983年   434篇
  1982年   577篇
  1981年   495篇
  1980年   513篇
  1979年   309篇
  1978年   347篇
  1977年   335篇
  1976年   285篇
  1975年   299篇
  1974年   259篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Acetylcholinesterase inhibitors may improve myelin integrity.   总被引:2,自引:0,他引:2  
Recent clinical trials have revealed that cholinergic treatments are efficacious in a wide spectrum of neuropsychiatric disorders that span the entire human lifespan and include disorders without cholinergic deficits. Furthermore, some clinical and epidemiological data suggest that cholinergic treatments have disease modifying/preventive effects. It is proposed that these observations can be usefully understood in a myelin-centered model of the human brain. The model proposes that the human brain's extensive myelination is the central evolutionary change that defines our uniqueness as a species and our unique vulnerability to highly prevalent neuropsychiatric disorders. Within the framework of this model the clinical, biochemical, and epidemiologic data can be reinterpreted to suggest that nonsynaptic effects of cholinergic treatments on the process of myelination and myelin repair contributes to their mechanism of action and especially to their disease modifying/preventive effects. The ability to test the model in human populations with safe and noninvasive imaging technologies makes it possible to undertake novel clinical trial efforts directed at primary prevention of some of the most prevalent and devastating of human disorders.  相似文献   
72.
73.
74.
75.
76.
An incipient boil should be treated early by radiotherapy, which usually aborts the lesion with prompt relief of discomfort and expedites involution without suppuration and without scarring, or by ultraviolet light, one treatment often proving effective. A localized and inactive boil should be freely incised, followed by distance radiation with ultraviolet light to hasten healing. In recurrent and chronic types confined to localized areas, fractional unfiltered or filtered roentgen rays are recommended, with generalized ultraviolet light baths for tonic effects.In the superficial type of carbuncle either roentgen or ultraviolet therapy causes prompt relief of pain, rapid regression and evacuation of pus. In the deep type, incision is generally the preferable method, supplemented by local and general actinotherapy.  相似文献   
77.
A brief review of the developmental background of the lateral cervical sinuses, fistulas, cysts and auricles has been presented. In all likelihood they are of branchial cleft origin. Surgical excision is the recommended treatment as shown in the cases described.  相似文献   
78.
阴茎勃起神经再生模型和机制的研究   总被引:1,自引:0,他引:1  
探明神经性勃起功能障碍(NED)的分子生物学机制以期对该类疾病进行神经调控干预,是男科学研究的当务之急。本文回顾了急性神经损伤、前列腺癌、糖尿病和帕金森病所致的NED的研究进展。通过利用大鼠阴茎勃起神经的盆腔大神经节(MPG),在体外构建一个三维培养体系来研究各种生长因子和细胞信号通路对神经再生的影响。体外结果表明脑源性神经生长因子(BDNF)通过JAK/STAT信号通路可显著促进NED的恢复,并在体内证实了该效应。因此,通过调控JAK/STAT信号通路来达到神经调控干预措施预防治疗神经性勃起功能障碍成为可能。  相似文献   
79.
The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy.  相似文献   
80.
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