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   705774篇
  免费   48874篇
  国内免费   1304篇
耳鼻咽喉   9166篇
儿科学   23285篇
妇产科学   17604篇
基础医学   110386篇
口腔科学   19955篇
临床医学   63750篇
内科学   134294篇
皮肤病学   16159篇
神经病学   49429篇
特种医学   25737篇
外国民族医学   76篇
外科学   104461篇
综合类   14818篇
现状与发展   2篇
一般理论   160篇
预防医学   51387篇
眼科学   16318篇
药学   53941篇
  3篇
中国医学   2359篇
肿瘤学   42662篇
  2019年   5430篇
  2018年   7858篇
  2017年   6104篇
  2016年   6819篇
  2015年   7550篇
  2014年   10260篇
  2013年   15377篇
  2012年   20489篇
  2011年   21488篇
  2010年   12715篇
  2009年   11930篇
  2008年   19983篇
  2007年   21504篇
  2006年   21897篇
  2005年   20438篇
  2004年   19985篇
  2003年   18939篇
  2002年   18451篇
  2001年   36325篇
  2000年   36894篇
  1999年   30377篇
  1998年   7876篇
  1997年   6663篇
  1996年   6969篇
  1995年   6627篇
  1994年   6096篇
  1993年   5589篇
  1992年   22967篇
  1991年   22924篇
  1990年   22309篇
  1989年   22076篇
  1988年   20035篇
  1987年   19418篇
  1986年   18467篇
  1985年   17305篇
  1984年   12697篇
  1983年   10741篇
  1982年   5921篇
  1979年   11518篇
  1978年   8128篇
  1977年   6832篇
  1976年   6594篇
  1975年   7268篇
  1974年   8498篇
  1973年   8141篇
  1972年   7658篇
  1971年   7127篇
  1970年   6877篇
  1969年   6306篇
  1968年   5780篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
62.
63.
A true comparison of long-term medical and surgical treatment in gastro-oesophageal reflux disease (GORD) is impossible as few studies have been carried out with adequate randomisation of the patients and long-term evaluation of quality of life. In general the control of the reflux symptoms is roughly equal with medical and surgical treatment. However, surgery can cause other symptoms such as dysphagia or non-specific epigastric discomfort or pain in some patients, which reduces the overall efficacy in controlling the symptoms. Based on a cost utility analysis, Heudebert et al. came to the conclusion that medical treatment was their preferred strategy for most patients with severe erosive oesophagitis.  相似文献   
64.
65.
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   
66.
Clinical versus ultrasonographic evaluation of scrotal disorders   总被引:1,自引:0,他引:1  
Clinical and ultrasonographic examinations of scrotal disorders were compared in 166 patients in order to determine their ability to distinguish between those diseases requiring surgery and those requiring clinical follow-up only. Ultrasound examinations were efficient in discriminating between normal and pathological findings. Extra-testicular lesions were readily differentiated from testicular ones. Although both clinical and ultrasonographic examinations had high sensitivity (90%) in detecting testicular cancer, the number of false positive findings was smaller after ultrasound examination. This gave a predictive value of a positive test of 53% after ultrasound examination but only 33% after clinical examination. Ultrasound examination may, therefore, reduce the number of surgical explorations in the scrotum and should be performed in patients with suspected testicular pathology based on history and palpatory findings.  相似文献   
67.
Summary Five monoclonal antibodies against the excretory/secretory (E/S) antigen of Toxocara canis were obtained and characterized. Immunoprecipitating activity was demonstrated in an in-vitro micropre-cipitating assay using live T. canis larvae. Their capacity to kill larvae was also shown in an in-vitro assay. Two zones of reactivity were observed in 7.5 and 12.5% SDS-PAGE (177-77 kD, 43-15 kD) of immunoprecipitates of human and mouse positive polyclonal anlisera. The murine monoclonal antibodies showed a common pattern of reactivity with the proteins in the 177-77 kD range.  相似文献   
68.
69.
Background.Computers that collect data from patients and provide both patients and practitioners with printed feedback on a range of health risks are a tool for assisting general practitioners with preventive care. This study assessed the impact of computer-generated printed feedback on cervical screening among women who were underscreened for cervical cancer.Method.Female attenders at two Australian general practices were randomly allocated to Experimental or Control groups. Women in both groups completed a health risk survey on a touch screen computer prior to their consultation. Those in the Experimental group received printed pages summarizing their results, including their eligibility for cervical screening and last Pap test, for themselves and their doctor. The number and proportion of underscreened women who had a Pap test in the 6 months after completing the computer survey, as determined by pathology records, were examined.Results.Of the 679 participants, 139 were classified as underscreened on the basis of self-report (74 Experimental, 65 Control) and 272 on the basis of their pathology records (148 Experimental, 124 Control). Overall about one-third of women had a test in the 6-month period, and the differences between the groups were not significant for women overall (18–70 years) or for women 18–49 years. Among women 50–70 who were underscreened based on self-report, those receiving the printout were more likely to have a Pap test in the next 6 months (P< 0.05). This pattern was also evident, but did not reach statistical significance, for older women who were underscreened based on pathology records.Conclusions.We are unable to draw conclusions regarding the effectiveness of the computer system due to the modest proportions of women screened, the small numbers, and the fact that the computer survey may have created an intervention effect in the Control group. As the study suggests the computer system is acceptable to women and may be effective for encouraging screening among older women, further exploration of the system is desirable.  相似文献   
70.
In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data.  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