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   2698276篇
  免费   195415篇
  国内免费   7263篇
耳鼻咽喉   35280篇
儿科学   88594篇
妇产科学   73404篇
基础医学   387544篇
口腔科学   77035篇
临床医学   251602篇
内科学   520816篇
皮肤病学   58240篇
神经病学   215568篇
特种医学   99909篇
外国民族医学   592篇
外科学   394604篇
综合类   61603篇
现状与发展   5篇
一般理论   950篇
预防医学   214132篇
眼科学   62705篇
药学   198233篇
  12篇
中国医学   6732篇
肿瘤学   153394篇
  2021年   20989篇
  2019年   22016篇
  2018年   31598篇
  2017年   23912篇
  2016年   26237篇
  2015年   29898篇
  2014年   41475篇
  2013年   62207篇
  2012年   85821篇
  2011年   90770篇
  2010年   53538篇
  2009年   49702篇
  2008年   83754篇
  2007年   88890篇
  2006年   89525篇
  2005年   85872篇
  2004年   82364篇
  2003年   78341篇
  2002年   75896篇
  2001年   131210篇
  2000年   134596篇
  1999年   112127篇
  1998年   30663篇
  1997年   27076篇
  1996年   27002篇
  1995年   25826篇
  1994年   23926篇
  1993年   22219篇
  1992年   86786篇
  1991年   84212篇
  1990年   81146篇
  1989年   77691篇
  1988年   71323篇
  1987年   69690篇
  1986年   66075篇
  1985年   62864篇
  1984年   46714篇
  1983年   39793篇
  1982年   23036篇
  1979年   41818篇
  1978年   29328篇
  1977年   24539篇
  1976年   23326篇
  1975年   24303篇
  1974年   29585篇
  1973年   28694篇
  1972年   26616篇
  1971年   24692篇
  1970年   22962篇
  1969年   21269篇
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
61.
62.
Leocani  L.  Comi  G. 《Neurological sciences》2006,27(1):s27-s29
Neurological Sciences - Brain plasticity, intended as the pattern of functional and structural changes in responses to environmental physiological or pathological events, is underlined by several...  相似文献   
63.
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating.  相似文献   
64.
65.
66.
67.
68.
Primary chemotherapy administered to breast cancer patientsis the best model to identify baseline features able to predictwhich patients may be most likely to benefit or not from a cytotoxicregimen. In the March issue of Annals of Oncology two papersevaluated the predictive role of immunohistochemical p53 expressionon  相似文献   
69.
70.
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   
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