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   2865210篇
  免费   227875篇
  国内免费   5235篇
耳鼻咽喉   41125篇
儿科学   89790篇
妇产科学   75099篇
基础医学   413858篇
口腔科学   82093篇
临床医学   262041篇
内科学   555012篇
皮肤病学   59461篇
神经病学   233238篇
特种医学   113175篇
外国民族医学   946篇
外科学   432532篇
综合类   67030篇
现状与发展   3篇
一般理论   1101篇
预防医学   228151篇
眼科学   67576篇
药学   216562篇
  7篇
中国医学   6179篇
肿瘤学   153341篇
  2018年   29522篇
  2017年   22779篇
  2016年   25200篇
  2015年   28387篇
  2014年   40444篇
  2013年   61482篇
  2012年   82715篇
  2011年   87421篇
  2010年   51495篇
  2009年   49034篇
  2008年   82574篇
  2007年   88266篇
  2006年   89259篇
  2005年   86310篇
  2004年   83438篇
  2003年   80239篇
  2002年   79115篇
  2001年   134890篇
  2000年   139173篇
  1999年   117237篇
  1998年   33266篇
  1997年   29965篇
  1996年   29937篇
  1995年   28794篇
  1994年   26985篇
  1993年   25149篇
  1992年   94360篇
  1991年   91701篇
  1990年   88851篇
  1989年   85905篇
  1988年   79653篇
  1987年   78267篇
  1986年   74205篇
  1985年   70552篇
  1984年   53197篇
  1983年   45241篇
  1982年   27032篇
  1981年   24122篇
  1979年   49755篇
  1978年   35014篇
  1977年   29470篇
  1976年   27907篇
  1975年   29613篇
  1974年   36233篇
  1973年   34353篇
  1972年   32260篇
  1971年   29759篇
  1970年   28159篇
  1969年   26168篇
  1968年   23819篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
951.
Despite growing concern with rural elderly populations, little attention has focused on their mental health, ways it may correlate with physical health, or how rural mental health patterns compare to urban. Popular wisdom contends that elderly people in general, and rural elderly persons in particular, are at increased risk for mental illness. This article examines these questions. A review of available literature suggests that elderly people may be at only slightly greater risk of mental illness than the population at large, though there are some indications that rates of depression may be somewhat higher among the elderly population. Much of this same literature implies that objective environmental conditions play a significant role in the incidence of depression. Analysis of data gathered in a statewide random poll (N = 743) indicates that while physical health tends to be poorer among rural populations, when health is held constant there is actually an inverse relationship between age and depression. Therefore, rural elderly persons are no more likely to be depressed than their urban counterparts despite harsher living conditions. Both conceptual and policy implications are discussed.  相似文献   
952.
Brain tissues from 38 patients with a clinical suspicion of encephalitis or encephalopathy were examined by two immunoenzymatic techniques for the detection of arboviral antigen. Group B arboviral antigen was identified in 23 of these tissues. This simple method could be used for the diagnosis of the causal agent of encephalitis.  相似文献   
953.
954.
955.
In six patients suffering from severe early dumping and six patients with late dumping after peptic ulcer surgery, the effect of the somatostatin analogue SMS 201-995 was compared with placebo. In early dumpers subcutaneous administration of 50 micrograms SMS 201-995 prior to meal ingestion induced a strong improvement of dumping symptoms as reflected by a decrease of the Sigstad dumping score from 12 +/- 2 during placebo to 5 +/- 2 (p less than 0.05). Furthermore, the postprandial increase of pulse rate was abolished; maximum pulse rate decreased from 85 +/- 7 beats/min to 67 +/- 7 beats/min (p less than 0.05). SMS 201-995 did not significantly affect postprandial changes in packed cell volume. In late dumpers 50 micrograms SMS 201-995 reduced peak plasma insulin after oral glucose from 173 +/- 16 mU/L during placebo to 35 +/- 9 mU/L during SMS 201-995 (p less than 0.05) and increased individual plasma glucose nadirs from 1.9 +/- 0.3 mmol/L to 7.5 +/- 3.3 mmol/L (p less than 0.01). Both in early and late dumpers SMS 201-995 improved postprandial expiratory breath hydrogen excretion indicating slowing of gastrointestinal hurry. SMS 201-995 is a powerful therapeutic agent for the management of patients suffering from the dumping syndrome after gastric surgery.  相似文献   
956.
Pulmonary valve insertion during reoperation for tetralogy of Fallot   总被引:1,自引:0,他引:1  
Our experience with pulmonary valve insertion during reoperation for residual lesions after initial open repair of tetralogy of Fallot in 15 patients is reported. Preoperatively, 14 patients were in moderate to severe congestive heart failure, and all 15 had decreased right ventricular (RV) function at cardiac catheterization. All 15 patients had pulmonary insufficiency but not as an isolated finding. The most common residual lesions encountered were ventricular septal defect in 9, tricuspid insufficiency in 11, and peripheral pulmonary arterial stenosis in 6. Tissue valves were inserted in all patients. Mean peak RV-left ventricular pressure ratio measured in the operating room decreased from 0.61 +/- 0.10 (+/- the standard deviation) to 0.47 +/- 0.17 (p less than 0.05). There were no operative deaths. At follow-up (mean, 33 months), all but 1 patient were in New York Heart Association Class I or II. Pulmonary valve insertion should be considered during reoperation for tetralogy of Fallot when pulmonary insufficiency and RV failure are present.  相似文献   
957.
958.
APACHE II score and abdominal sepsis. A prospective study   总被引:7,自引:0,他引:7  
Therapeutic trials for intra-abdominal sepsis require pretreatment stratification; physiologic scoring has been recently proposed for this purpose. We have prospectively tested the validity of one such scoring system, namely, the Acute Physiology and Chronic Health Evaluation (APACHE II). As part of a larger database, we correlated APACHE II scores with mortality in 100 patients hospitalized for generalized peritonitis or abdominal abscess. Use of steroids was recorded because of our suspicion that steroids increase mortality but blunt the physiologic response to sepsis. Thirty-one patients died, including 12 of 19 patients receiving steroids. Stepwise discriminant analysis revealed that the APACHE II score and steroid use were each independently associated with the rate of mortality. We report a prospective validation of pretreatment APACHE II scoring in abdominal sepsis. Steroid use is an independent risk factor.  相似文献   
959.
A total of 50 consecutive patients who were treated in JIPMER Hospital between 1970 and 1981 for corrosive injuries of the oesophagus and stomach were analysed. There were 23 males and 27 females. All but seven presented with dysphagia due to an established stricture. In addition seven of them had associated stricture of the stomach. They were treated with either repeated dilatations or, in selected cases, oesophageal replacement. Perforation of the oesophagus is an important complication associated with oesophageal dilatation indicating the need for oesophageal replacement in multiple or long dense strictures. Results are quite satisfactory with both modalities of treatment. However, oesophageal replacement surgery, performed properly in selected cases, offers a permanent solution to these unfortunate victims.  相似文献   
960.
Choledochal cyst is an unusual but serious condition which most commonly affects Oriental people. Recent experience of three patients with this condition in whom diagnosis was made by ultrasound examination is reported. Cholangiography (ERCP or PTC) was performed in two of the cases to define the anatomy. All three cases were successfully managed by cyst excision and biliary reconstruction by Roux-en-Y hepaticojejunostomy. The rationale for and importance of cyst excision are discussed.  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