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   1871929篇
  免费   126061篇
  国内免费   3800篇
耳鼻咽喉   23079篇
儿科学   62031篇
妇产科学   49324篇
基础医学   258407篇
口腔科学   50701篇
临床医学   164780篇
内科学   364406篇
皮肤病学   39566篇
神经病学   147472篇
特种医学   72751篇
外国民族医学   244篇
外科学   286051篇
综合类   41447篇
现状与发展   4篇
一般理论   543篇
预防医学   142317篇
眼科学   43102篇
药学   133386篇
  10篇
中国医学   5143篇
肿瘤学   117026篇
  2021年   12993篇
  2019年   13754篇
  2018年   40276篇
  2017年   31193篇
  2016年   34584篇
  2015年   20047篇
  2014年   27271篇
  2013年   39162篇
  2012年   59770篇
  2011年   75556篇
  2010年   50397篇
  2009年   41646篇
  2008年   70120篇
  2007年   75417篇
  2006年   56449篇
  2005年   55168篇
  2004年   54700篇
  2003年   52911篇
  2002年   49291篇
  2001年   92490篇
  2000年   94400篇
  1999年   77535篇
  1998年   20111篇
  1997年   17619篇
  1996年   17597篇
  1995年   16980篇
  1994年   15501篇
  1993年   14262篇
  1992年   57756篇
  1991年   55667篇
  1990年   53381篇
  1989年   51173篇
  1988年   46501篇
  1987年   45294篇
  1986年   42536篇
  1985年   40323篇
  1984年   29596篇
  1983年   25117篇
  1982年   14072篇
  1979年   25719篇
  1978年   17732篇
  1977年   15025篇
  1976年   14019篇
  1975年   14683篇
  1974年   17799篇
  1973年   17102篇
  1972年   15802篇
  1971年   14592篇
  1970年   13585篇
  1969年   12658篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
Although surgical lung resection could improve prognosis in some patients with multidrug-resistant tuberculosis (MDR-TB), there are no reports on the optimal candidates for this surgery. The aim of the present study was to elucidate the prognostic factors for surgery in patients with MDR-TB. Patients who underwent lung resection for the treatment of MDR-TB between March 1993 and December 2004 were included in the present study. Treatment failure was defined as greater than or equal to two of the five cultures recorded in the final 12 months of treatment being positive, any one of the final three cultures being positive, or the patient having died during treatment. The variables that affected treatment outcomes were identified through univariate and multivariate logistic regression analysis. In total, 79 patients with MDR-TB were included in the present study. The treatment outcomes of 22 (27.8%) patients were classified as failure. A body mass index <18.5 kg x m(-2), primary resistance, resistance to ofloxacin and the presence of a cavitary lesion beyond the range of the surgical resection were associated with treatment failure. Low body mass index, primary resistance, resistance to ofloxacin and cavitary lesions beyond the range of resection are possible poor prognostic factors for surgical lung resection in multidrug-resistant tuberculosis patients.  相似文献   
45.
46.
47.
48.
49.
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   
50.
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   
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