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   84995篇
  免费   5827篇
  国内免费   506篇
耳鼻咽喉   1040篇
儿科学   2376篇
妇产科学   1807篇
基础医学   10405篇
口腔科学   1383篇
临床医学   8720篇
内科学   18191篇
皮肤病学   1690篇
神经病学   7016篇
特种医学   3156篇
外国民族医学   1篇
外科学   13511篇
综合类   1640篇
一般理论   80篇
预防医学   5069篇
眼科学   2379篇
药学   5726篇
中国医学   351篇
肿瘤学   6787篇
  2023年   507篇
  2022年   920篇
  2021年   2025篇
  2020年   1232篇
  2019年   1860篇
  2018年   2287篇
  2017年   1707篇
  2016年   1844篇
  2015年   2208篇
  2014年   3176篇
  2013年   3933篇
  2012年   6051篇
  2011年   6307篇
  2010年   3563篇
  2009年   3069篇
  2008年   5291篇
  2007年   5531篇
  2006年   5528篇
  2005年   5367篇
  2004年   5015篇
  2003年   4660篇
  2002年   4249篇
  2001年   1496篇
  2000年   1312篇
  1999年   1300篇
  1998年   919篇
  1997年   716篇
  1996年   588篇
  1995年   539篇
  1994年   513篇
  1993年   455篇
  1992年   661篇
  1991年   635篇
  1990年   593篇
  1989年   554篇
  1988年   507篇
  1987年   510篇
  1986年   458篇
  1985年   414篇
  1984年   384篇
  1983年   326篇
  1982年   296篇
  1981年   261篇
  1980年   213篇
  1979年   221篇
  1978年   166篇
  1977年   141篇
  1976年   119篇
  1975年   107篇
  1974年   104篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
Opportunistic infections occur in patients with rheumatic diseases treated with low dose methotrexate (MTX) with or without other immunosuppressants. Our case report illustrates a fatal case of Pneumocystis carinii pneumonia in a patient with rheumatoid arthritis treated with low dose MTX and glucocorticoid. A review of the literature reveals other opportunistic infections such as Cryptococcus, Nocardia, and herpes zoster presenting in such patients. These occurrences suggest that MTX should be used cautiously in patients with rheumatic disease receiving concomitant medical therapy.  相似文献   
133.
Immunohistochemical expression of carbonic anhydrase isoenzyme II (CAII) was demonstrated in a population of fibrous astrocytes in a young lamb and an adult sheep. Such cells were identified by co-expression of CAII and glial fibrillary acidic protein, nuclear morphology and their contribution of glial fibrillary acidic protein reactive processes to the glial limitans. Similar cells were not identified in neonatal lambs. As in man and mouse, CAII was also expressed in choroid plexus epithelium occurring in neonate, young and adult sheep brain. In contrast, however, to man and mouse, CAII was not expressed in sheep oligodendrocytes.  相似文献   
134.
Book Review     
Paediatric Forensic Medicine and Pathology Edited by J. K. Mason London: Chapman and Hall Medical [Published in United States by Van Nostrand Reinhold9.95. New York], 1989, xii + 516 pp, $13  相似文献   
135.
136.
Background : Mortality rates from gastric cancer, apart from those derived from Japanese series, remain poor. This paper sought to determine the present outcome of gastric carcinoma in a predominantly Chinese population in Singapore. Prognostic factors useful in predicting survival were also evaluated in this population. Method : All cases of histologically confirmed gastric adenocarcinoma presenting in 1992 were entered into a prospective database. Prognostic factors related to age, sex, site of disease, depth of invasion, histological grade, nodal status and stage of disease were evaluated in patients with resectable disease to determine their utility in predicting survival. Results : Of 1310 consecutive patients with histologically proven adenocarcinomas, 37% had distant metastases at presentation predominantly in the liver (21%) and peritoneal cavity (20%). Sixty-four per cent of patients underwent surgery and in only 51% of these patients was resection of the turnour possible. Stages 111 and IV (T4N2) locally advanced disease were present in 38% of patients. Thus the majority of patients presented with late or metastatic disease (75%, stages 111 and IV). Sixty per cent of patients were alive at I year and 40% at 2 years after resection of the tumour (Kaplan-Meier survival plots). In contrast, no patient survived longer than a year if the tumour was not resectable (P < 0.001, log-rank test). Median survival of patients without surgery was 12 weeks. Median survival for patients with resected stage IV disease was 23 weeks, compared to 18 weeks after surgical bypass. Age, sex, site, depth of invasion and histological grade did not significantly predict survival. Patients with node-negative disease survived longer (2 year, 70%) than those with nodal involvement (2 years, 44%; P = 0.06, log-rank test). Pathologic staging with the TNM system was useful in predicting survival (P < 0.001). Sixty per cent of patients with stage I and II disease were alive at 2 years compared to 54% with stage III disease and 0% with stage IV disease. Conclusion : The prognosis of stomach cancer remains poor, due predominantly to late presentation. Pathologic TNM staging and nodal status were useful in predicting survival outcome after resection. If the tumour were resectable, survival was appreciable even in patients with advanced stage III (2 years, 54%) and stage IV (1 year, 40%) disease. Strategies to improve outcome should focus on early detection of gastric carcinomas.  相似文献   
137.
The information needs of women newly diagnosed with breast cancer   总被引:4,自引:0,他引:4  
Nurses can play a key role in patient education, including providing patients with useful and approrate information Rather than focusing on the process of education or information giving by nurses, this study places emphasis on the content of that information by taking the patients'perspective and asking the patients themselves what particular types of information are perceived as important at a specific point in time The aim of the study was to explore what particular types of information were important to women newly diagnosed with breast cancer, to enable nurses and other health care professionals to utilize their time as effectively as possible and provide a high-quality service to individuals in their care Women with breast cancer (a mean of 2 5 weeks from diagnosis) were interviewed and asked to compare items of information The items of information were presented m pairs and the women stated a preference for one item in that pan- Thirty-six pairs were presented in total The analysis involved the use of a Thurstone scaling model, which allowed rank ordermgs, or profiles of information needs, to be developed, reflecting the perceived importance of each item Information about the likelihood of cure, the spread of the disease and treatment options were perceived as the most important items of information at the tune of diagnosis Other information needs, in order of descending priority, included information about the risk to family, side-effects  相似文献   
138.
139.
140.
This study uses data from the Epidemiologic Catchment Area (ECA) surveys to examine the strength of the association between psychotic symptoms and violent behaviour, controlling for underlying mental disorder, substance abuse, sociodemographic characteristics and use of mental health services, in a representative sample of community residents. A replication is conducted of a study that found an increased risk of violence associated with a particular cluster of psychotic symptoms involving perceived threat and internal control-override (TCO). Respondents who reported TCO symptoms were about twice as likely to engage in assaultive behaviour as those with hallucinations or other psychotic symptoms, and about five times as likely as those with no mental disorder. The combination of substance use disorders with TCO symptoms added significantly to the risk of violent behaviour. Those with a history of using mental health services also posed a higher risk of violence, probably due to the differential selection of more severely ill and ‘dangerous’ individuals into treatment settings. Copyright © 1996 Whurr Publishers Ltd.  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