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   128073篇
  免费   7649篇
  国内免费   1591篇
耳鼻咽喉   1731篇
儿科学   3334篇
妇产科学   4469篇
基础医学   19591篇
口腔科学   4063篇
临床医学   10210篇
内科学   23086篇
皮肤病学   2705篇
神经病学   8872篇
特种医学   4315篇
外国民族医学   3篇
外科学   18162篇
综合类   5353篇
一般理论   37篇
预防医学   9428篇
眼科学   3030篇
药学   10716篇
中国医学   831篇
肿瘤学   7377篇
  2021年   1123篇
  2019年   1180篇
  2018年   1758篇
  2017年   1271篇
  2016年   1333篇
  2015年   1578篇
  2014年   2086篇
  2013年   2705篇
  2012年   3900篇
  2011年   4214篇
  2010年   2509篇
  2009年   2278篇
  2008年   3722篇
  2007年   4014篇
  2006年   4029篇
  2005年   3532篇
  2004年   3330篇
  2003年   3051篇
  2002年   2913篇
  2001年   7034篇
  2000年   7198篇
  1999年   5945篇
  1998年   1924篇
  1997年   1469篇
  1996年   1014篇
  1995年   951篇
  1992年   3935篇
  1991年   3980篇
  1990年   3763篇
  1989年   3755篇
  1988年   3633篇
  1987年   3469篇
  1986年   3265篇
  1985年   3131篇
  1984年   2183篇
  1983年   1907篇
  1982年   1057篇
  1979年   2026篇
  1978年   1270篇
  1977年   1062篇
  1976年   984篇
  1975年   1279篇
  1974年   1449篇
  1973年   1501篇
  1972年   1435篇
  1971年   1332篇
  1970年   1220篇
  1969年   1196篇
  1968年   1100篇
  1967年   961篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Local hyperthermia of the prostate was used to treat 72 patients who had an indwelling catheter because of urinary retention caused by benign prostatic hypertrophy. One month after completion of treatment 50% of patients were able to dispense with the catheter and 1 year later 40% remained catheter-free. The best results were achieved in patients who underwent 6 to 10 treatment sessions in conjunction with cyproterone acetate 50 mg tid administered during the treatment period only.  相似文献   
84.
The involuntary hospitalisation of psychiatric patients continues to be a controversial issue. All patients certified and admitted to Sterkfontein Hospital under Sections 9 and 12 of the Mental Health Act, No. 18 of 1973, over a 4-week period were surveyed. Almost 40% were admitted as urgent certifications. The majority of the patients in the sample were black, single, urban and had either primary or limited high school education. Most patients had been referred from academic/teaching and provincial hospitals. The average duration of hospital stay was 7.2 weeks, with only 1 patient eventually being transferred to a ward for chronic patients within the hospital, which suggests that Sterkfontein Hospital functions largely as an acute psychiatric facility. There was a discrepancy of approximately 30% between the assessments of the certifying and ward doctors, probably as a result of differing uses of terminology. Not only are more community psychiatric services needed, but communication between psychiatry and the other medical disciplines should be improved.  相似文献   
85.
86.
87.
Prolongation of the action potential duration of dorsal root ganglion (DRG) neurons by low (nM) concentrations of opioids occurs through activation of excitatory opioid receptors that are positively coupled via Gs regulatory protein to adenylate cyclase. Previous results suggested GM1 ganglioside to have an essential role in regulating this excitatory response, but not the inhibitory (APD-shortening) response to higher (μM) opioid concentrations. Furthermore, it was proposed that synthesis of GM1 is upregulated by prolonged activation of excitatory opioid receptor functions. To explore this possibility we have utilized cultures of hybrid F11 cells to carry out closely correlated electrophysiological and biochemical analyses of the effects of chronic opioid treatment on a homogeneous population of clonal cells which express many functions characteristic of DRG neurons. We show that chronic opioid exposure of F11 cells does, in fact, result in elevated levels of GM1 as well as cyclic adenosine monophosphate (AMP), concomitant with the onset of opioid excitatory supersensitivity as manifested by naloxone-evoked decreases in voltage-dependent membrane K+ currents. Such elevation of GM1 would be expected to enhance the efficacy of excitatory opioid receptor activation of the Gs/adenylate cyclase/cyclic AMP system, thereby providing a positive feedback mechanism that may account for the remarkable supersensitivity of chronic opioid-treated neurons to the excitatory effects of opioid agonists as well as antagonists. These in vitro findings may provide novel insights into the mechanisms underlying naloxone-precipitated withdrawal syndromes and opioid-induced hyperalgesia after chronic opiatf addiction in vivo. © 1995 Wiley-Liss, Inc.  相似文献   
88.
89.
Clinicopathologic correlation of pigmented epiretinal membranes   总被引:1,自引:0,他引:1  
We performed clinicopathologic correlation on ten surgically removed pigmented epiretinal membranes causing macular pucker. All cases occurred in eyes with existing retinal holes or tears, including eight cases of macular pucker after previous retinal detachment. These cases probably represented a limited form of proliferative vitreoretinopathy. All membranes contained pigment epithelial cells with polarity, basement membrane, and melanosomes. Cytoplasmic melanin granules accounted for the clinical feature of pigmentation in these eyes.  相似文献   
90.
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