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   3469篇
  免费   266篇
  国内免费   28篇
耳鼻咽喉   27篇
儿科学   213篇
妇产科学   63篇
基础医学   376篇
口腔科学   91篇
临床医学   333篇
内科学   817篇
皮肤病学   51篇
神经病学   133篇
特种医学   459篇
外科学   308篇
综合类   161篇
一般理论   1篇
预防医学   293篇
眼科学   53篇
药学   183篇
  1篇
中国医学   1篇
肿瘤学   199篇
  2022年   24篇
  2021年   63篇
  2020年   44篇
  2019年   60篇
  2018年   92篇
  2017年   56篇
  2016年   63篇
  2015年   68篇
  2014年   65篇
  2013年   143篇
  2012年   92篇
  2011年   109篇
  2010年   104篇
  2009年   139篇
  2008年   96篇
  2007年   146篇
  2006年   122篇
  2005年   107篇
  2004年   84篇
  2003年   77篇
  2002年   57篇
  2001年   82篇
  2000年   94篇
  1999年   86篇
  1998年   123篇
  1997年   139篇
  1996年   125篇
  1995年   88篇
  1994年   96篇
  1993年   111篇
  1992年   62篇
  1991年   50篇
  1990年   46篇
  1989年   66篇
  1988年   77篇
  1987年   71篇
  1986年   58篇
  1985年   47篇
  1984年   39篇
  1983年   35篇
  1982年   32篇
  1981年   50篇
  1980年   35篇
  1979年   23篇
  1978年   19篇
  1977年   33篇
  1976年   31篇
  1973年   21篇
  1969年   17篇
  1967年   17篇
排序方式: 共有3763条查询结果,搜索用时 31 毫秒
1.
2.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.  相似文献   
3.
The pilot study for a sentinel health events surveillance system for deaths among persons under age 45 with diabetes was conducted in six states in 1984 and 1985. Two hundred and thirty-three events were identified. Information from death certificates, physicians, and families revealed that 22% died from acute complications of diabetes and 53% from chronic complications. Blood pressure measurement and urinalysis testing had been performed in the last year for almost all of the decedents, but other preventive practices were reported less frequently. Hypertension was present in 57% and of those, was not controlled in 73%. Forty-four percent were cigarette smokers at the time of death. Agreement between physicians and families was generally higher for clinical conditions than for care practices. This surveillance system appears to yield information about the health care of persons with diabetes not readily available from other sources, although modifications may be necessary before implementation.  相似文献   
4.
Background: Pemetrexed and cisplatin have recently been shown to significantly improve survival compared with cisplatin alone. However, there are only limited data reflecting teaching hospital experience outside a clinical trial. Pemetrexed has only been available in Australia on a restricted basis since 2002. We reviewed our experience of patients treated on the Australian ‘Special Access Scheme’ at three major thoracic oncology units. Methods: Charts were reviewed for all patients enrolled on the scheme. Data was extracted on age, World Health Organization (WHO) performance status, histology, prior therapy, time from diagnosis to starting pemetrexed, chemotherapy (pemetrexed alone or with a platinum), cycle number, response rate, actuarial progression‐free and overall survival. Doses were cisplatin 75 mg/m2 or carboplatin AUC = 5 and pemetrexed 500 mg/m2 every 21 days. Results: 52 patients (32 male and 20 female) were reviewed. Median age was 58 years and 88% were WHO 0–1. Histology included 54% epithelial, 17% biphasic (epithelial and sarcomatoid) and 21% undefined. The median time from diagnosis to administration of pemetrexed was 145 days. Sixty‐five percent had minimal surgical intervention with video assisted thoracoscopy, pleurodesis and biopsy, while 19% had received prior palliative radiation. Seventy‐one percent were chemotherapy naïve, the remaining 29% having received previous platinum and/or gemcitabine regimens. Twenty‐three percent had pemetrexed alone, 35% in combination with carboplatin and 42% with cisplatin. The median number of cycles was 4 (range 1–13). The response rate was 33%. No toxicity was observed in 20% grade 3–4 toxicity in 10% (majority nausea/vomiting). The median progression‐free and overall survival times from starting pemetrexed were 184 days and 298 days, respectively. Conclusions: Pemetrexed‐based regimens are safe and effective in a community setting in malignant mesothelioma.  相似文献   
5.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
6.
7.
8.
The best quality long-lasting results require attention to the diagnosis of the precise anatomic problems followed by the architectural planning--the art of making beautiful highlights, shadows, and curves where indicated to produce a result that is aesthetically pleasing. Attention to the details of the surgical planning, execution of surgery, and postoperative care are essential to minimize untoward results and problems and produce a happy patient and pleased surgeon.  相似文献   
9.
10.
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