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   1353109篇
  免费   95339篇
  国内免费   3039篇
耳鼻咽喉   19867篇
儿科学   40616篇
妇产科学   38986篇
基础医学   189209篇
口腔科学   40495篇
临床医学   114300篇
内科学   266126篇
皮肤病学   30579篇
神经病学   107431篇
特种医学   54060篇
外国民族医学   440篇
外科学   210447篇
综合类   31473篇
现状与发展   6篇
一般理论   449篇
预防医学   93479篇
眼科学   32028篇
药学   101722篇
  4篇
中国医学   3196篇
肿瘤学   76574篇
  2018年   12686篇
  2016年   11302篇
  2015年   12607篇
  2014年   17650篇
  2013年   26367篇
  2012年   34522篇
  2011年   36444篇
  2010年   21659篇
  2009年   20929篇
  2008年   34584篇
  2007年   37593篇
  2006年   38003篇
  2005年   36632篇
  2004年   35594篇
  2003年   34466篇
  2002年   33935篇
  2001年   63658篇
  2000年   65373篇
  1999年   55439篇
  1998年   14698篇
  1997年   13501篇
  1996年   12975篇
  1995年   12253篇
  1994年   11483篇
  1992年   42781篇
  1991年   41295篇
  1990年   40568篇
  1989年   39568篇
  1988年   36979篇
  1987年   36418篇
  1986年   34912篇
  1985年   33112篇
  1984年   24839篇
  1983年   21066篇
  1982年   12678篇
  1981年   11574篇
  1979年   23931篇
  1978年   17074篇
  1977年   14838篇
  1976年   13393篇
  1975年   15270篇
  1974年   18087篇
  1973年   17567篇
  1972年   16813篇
  1971年   15719篇
  1970年   14916篇
  1969年   14347篇
  1968年   13460篇
  1967年   12015篇
  1966年   11258篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Premalignant lesions of the penis include cutaneous horn, balanitis xerotica obliterans, and leukoplakia. The true incidence of progression of each of these to squamous-cell carcinoma is unknown. Bowenoid papulosis, erythroplasia of Queyrat, and Bowen's disease are histologically identical to in situ carcinoma. Although the first is consistently benign, the latter two regularly evolve into invasive cancer. Malignant scrotal lesions include squamous-cell carcinoma, liposarcoma, leiomyosarcoma, basal-cell carcinoma, extramammary Paget's disease, erythroplasia of Queyrat, malignant melanoma, and metastases. Hemangioma can be confused with carcinoma.  相似文献   
102.
A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in Heidelberg and Giessen (FRG) provided information on occupational factors in 200 patients and 800 controls (adjusted to sex, age and area of living; 4:1 matched design). The number of subjects exposed to wood dusts, organic chemicals, coal products or to cement was significantly elevated in the tumour group. An increased risk for head and neck cancer was observed after exposition to wood dust (RR = 2,2), organic compounds (RR = 2,4), coal products (RR = 2,7) and especially to cement (RR = 4,4). The cancer risk due to cement exposition showed a positive correlation to the duration of exposition and remained significantly elevated after adjustment for alcohol and tobacco consumption.  相似文献   
103.
Results of an hierarchical factor analysis with university students (N = 101) do not support the construct validity of the Multidimensional Aptitude Battery (MAB). Although the MAB Full Scale IQ seems to be a valid measure of general mental ability, the construct validity of the Verbal and Performance scale IQs is not supported. Therefore, the Verbal and Performance IQs should be interpreted with caution, if at all. In addition, re-analysis of previous investigations of the MAB underscores the importance of ascertaining the reading level of subjects prior to the administration of the MAB. Marginal reading proficiency, especially on a timed paper-and-pencil test such as the MAB, will confound results.  相似文献   
104.
105.
Analysis of accident logs in child day care centers indicates that biting is common, especially among toddlers 13 to 30 months of age. Children of this age often lack appropriate verbal skills and resort to aggressive means to achieve their goals. Still awkward in gross-motor skills, toddlers can also suffer self-bites following accidental falls. According to medical reports, human bites sometimes are more virulent than animal bites and can cause severe trauma. Although the AIDS virus has been cultured from saliva, transmission from saliva alone has not been documented. Bite injuries in day care, however, usually are minor and can be treated by washing, applying cold compresses, and comforting the child. Suggested methods to diminish the frequency of biting in day care include physical changes within the room, behavior modification, and other classroom management techniques.  相似文献   
106.
107.
To study the effect of alcohol on glucose and insulin metabolism,a simultaneous infusion of glucose and insulin was given for150 min to healthy volunteers, once during alcohol and onceduring calorie-free gingerale (control) ingestion. During alcoholintake, the average steady-state (between 100 and 150 min) glucoseof 5.44±0.39 mmol/1. and the average steady-state insulinof 6.3±1.1 ng/ml were significantly higher than those(4.0±0.39 mmol/1. of glucose and 4.4±0.6 ng/mlof insulin) observed during the control state. Despite the highersteady-state insulin concentrations, the glucose metabolismwas significantly less during alcohol ingestion. These findingssuggest alcohol-induced impairment in glucose metabolism iscaused by a decreased tissue sensitivity to insulin.  相似文献   
108.
One of our patients had trouble maintaining therapeutic and safe levels of theophylline, even though we were careful in planning and monitoring her drug regimen. This case report shows how we were able to use principles of pharmacokinetics to distinguish among plausible explanations for her experience. We discovered that she was not taking the drug consistently as prescribed and that supervised administration resolved apparent contradictions between doses and serum levels. We believe that physicians can use the same information and methods that we used to get better and safer results from theophylline therapy.  相似文献   
109.
110.
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