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   802109篇
  免费   55534篇
  国内免费   1611篇
耳鼻咽喉   10415篇
儿科学   25739篇
妇产科学   19783篇
基础医学   122376篇
口腔科学   21987篇
临床医学   73124篇
内科学   155295篇
皮肤病学   17241篇
神经病学   57848篇
特种医学   28964篇
外国民族医学   79篇
外科学   120090篇
综合类   16182篇
现状与发展   3篇
一般理论   233篇
预防医学   59038篇
眼科学   18872篇
药学   60101篇
  3篇
中国医学   2501篇
肿瘤学   49380篇
  2021年   6987篇
  2019年   6941篇
  2018年   9709篇
  2017年   7440篇
  2016年   8314篇
  2015年   9312篇
  2014年   12881篇
  2013年   19542篇
  2012年   26379篇
  2011年   27690篇
  2010年   16200篇
  2009年   15146篇
  2008年   25828篇
  2007年   28030篇
  2006年   28144篇
  2005年   26913篇
  2004年   26265篇
  2003年   24850篇
  2002年   24337篇
  2001年   37105篇
  2000年   37479篇
  1999年   31151篇
  1998年   9113篇
  1997年   7748篇
  1996年   7885篇
  1995年   7552篇
  1994年   6901篇
  1993年   6301篇
  1992年   23531篇
  1991年   23430篇
  1990年   22752篇
  1989年   22531篇
  1988年   20464篇
  1987年   19869篇
  1986年   18905篇
  1985年   17788篇
  1984年   13388篇
  1983年   11466篇
  1982年   6857篇
  1979年   11960篇
  1978年   8651篇
  1977年   7401篇
  1976年   7070篇
  1975年   7678篇
  1974年   8824篇
  1973年   8461篇
  1972年   7896篇
  1971年   7295篇
  1970年   7057篇
  1969年   6417篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
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   
82.
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   
83.
84.
85.
86.
Acute renal failure (ARF) developed in a 7-week-old infant due to bilateral candidal bezoars (fungal balls) causing obstruction at the pelviureteric junction. The baby was born at term with an appropriate birthweight, and had been treated with broad-spectrum antibiotics for respiratory distress and septicemia during the 1st week of life. Recovery from ARF followed renal decompression with bilateral nephrostomy tube placement and parenteral administration of amphotericin B and 5-flucytosine. Received August 21, 1996; received in revised form and accepted January 3, 1997  相似文献   
87.
88.
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP.  相似文献   
89.
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