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   1736486篇
  免费   125694篇
  国内免费   3896篇
耳鼻咽喉   22536篇
儿科学   57083篇
妇产科学   47072篇
基础医学   246149篇
口腔科学   49656篇
临床医学   153932篇
内科学   344316篇
皮肤病学   40122篇
神经病学   134627篇
特种医学   65020篇
外国民族医学   242篇
外科学   263066篇
综合类   39165篇
现状与发展   4篇
一般理论   534篇
预防医学   127911篇
眼科学   40906篇
药学   125880篇
  7篇
中国医学   4629篇
肿瘤学   103219篇
  2021年   13819篇
  2019年   14595篇
  2018年   21629篇
  2017年   16160篇
  2016年   17504篇
  2015年   19864篇
  2014年   27416篇
  2013年   39741篇
  2012年   55385篇
  2011年   58147篇
  2010年   34430篇
  2009年   32082篇
  2008年   53768篇
  2007年   57147篇
  2006年   57607篇
  2005年   54806篇
  2004年   52843篇
  2003年   50043篇
  2002年   48234篇
  2001年   93059篇
  2000年   95157篇
  1999年   78137篇
  1998年   19955篇
  1997年   17430篇
  1996年   17539篇
  1995年   16883篇
  1994年   15398篇
  1993年   14167篇
  1992年   57867篇
  1991年   55699篇
  1990年   53364篇
  1989年   51070篇
  1988年   46399篇
  1987年   45206篇
  1986年   42473篇
  1985年   40227篇
  1984年   29506篇
  1983年   25041篇
  1982年   13959篇
  1979年   25614篇
  1978年   17629篇
  1977年   14962篇
  1976年   13950篇
  1975年   14635篇
  1974年   17735篇
  1973年   17048篇
  1972年   15761篇
  1971年   14537篇
  1970年   13511篇
  1969年   12607篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Infections due to Penicillium species other than P.marneffei are rare. We identified a boy with X-linked chronic granulomatous disease (X-CGD) with a pulmonary nodule and adjacent rib osteomyelitis caused by Penicillium piceum. The only sign of infection was an elevated sedimentation rate. P. piceum was isolated by fine needle aspirate and from excised infected tissues. Surgical removal and one year of voriconazole treatment were very well tolerated and led to complete recovery. Microbiological, microscopic and molecular studies support the fungal diagnosis. P. piceum should be considered as a relevant pathogen in immunocompromised patients.  相似文献   
33.
34.
35.
36.
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   
37.
38.
39.
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   
40.
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