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   3235825篇
  免费   257867篇
  国内免费   6691篇
耳鼻咽喉   46029篇
儿科学   102270篇
妇产科学   89263篇
基础医学   453352篇
口腔科学   92567篇
临床医学   295839篇
内科学   632537篇
皮肤病学   69151篇
神经病学   272273篇
特种医学   127047篇
外国民族医学   1187篇
外科学   485309篇
综合类   78377篇
现状与发展   4篇
一般理论   1331篇
预防医学   262814篇
眼科学   76553篇
药学   236731篇
  5篇
中国医学   6565篇
肿瘤学   171179篇
  2018年   34732篇
  2017年   26643篇
  2016年   29588篇
  2015年   33444篇
  2014年   48121篇
  2013年   72849篇
  2012年   98270篇
  2011年   103839篇
  2010年   61279篇
  2009年   58606篇
  2008年   97532篇
  2007年   103495篇
  2006年   104531篇
  2005年   101699篇
  2004年   97561篇
  2003年   93824篇
  2002年   91812篇
  2001年   150905篇
  2000年   155623篇
  1999年   131043篇
  1998年   38432篇
  1997年   34828篇
  1996年   34477篇
  1995年   33069篇
  1994年   30745篇
  1993年   28812篇
  1992年   103591篇
  1991年   99575篇
  1990年   95897篇
  1989年   92206篇
  1988年   85512篇
  1987年   84096篇
  1986年   79273篇
  1985年   75752篇
  1984年   57831篇
  1983年   49265篇
  1982年   30176篇
  1981年   26845篇
  1979年   53505篇
  1978年   37753篇
  1977年   31666篇
  1976年   29768篇
  1975年   31007篇
  1974年   38137篇
  1973年   36440篇
  1972年   34192篇
  1971年   31447篇
  1970年   29741篇
  1969年   27672篇
  1968年   25621篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia.  相似文献   
72.
73.
74.
75.
76.
77.
78.
CONTEXT: Although the nonmedical use of stimulant drugs such as cocaine and methamphetamine is increasingly common in many rural areas of the United States, little is known about the health beliefs of people who use these drugs. PURPOSE: This research describes illicit stimulant drug users' views on health and health-related concepts that may affect their utilization of health care services. METHODS: A respondent-driven sampling plan was used to recruit 249 not-in-treatment, nonmedical stimulant drug users who were residing in 3 rural counties in west central Ohio. A structured questionnaire administered by trained interviewers was used to collect information on a range of topics, including current drug use, self-reported health status, perceived need for substance abuse treatment, and beliefs about health and health services. FINDINGS: Participants reported using a wide variety of drugs nonmedically, some by injection. Alcohol and marijuana were the most commonly used drugs in the 30 days prior to the interview. Powder cocaine was used by 72.3% of the sample, crack by 68.3%, and methamphetamine by 29.7%. Fair or poor health status was reported by 41.3% of the participants. Only 20.9% of the sample felt they needed drug abuse treatment. Less than one third of the sample reported that they would feel comfortable talking to a physician about their drug use, and 65.1% said they preferred taking care of their problems without getting professional help. CONCLUSIONS: Stimulant drug users in rural Ohio are involved with a range of substances and hold health beliefs that may impede health services utilization.  相似文献   
79.
PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads.  相似文献   
80.
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