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   2581篇
  免费   215篇
  国内免费   25篇
耳鼻咽喉   81篇
儿科学   190篇
妇产科学   22篇
基础医学   268篇
口腔科学   85篇
临床医学   271篇
内科学   544篇
皮肤病学   46篇
神经病学   173篇
特种医学   364篇
外科学   223篇
综合类   56篇
一般理论   3篇
预防医学   191篇
眼科学   34篇
药学   151篇
  1篇
中国医学   1篇
肿瘤学   117篇
  2022年   10篇
  2021年   29篇
  2020年   13篇
  2019年   32篇
  2018年   45篇
  2017年   44篇
  2016年   41篇
  2015年   52篇
  2014年   54篇
  2013年   81篇
  2012年   78篇
  2011年   66篇
  2010年   69篇
  2009年   100篇
  2008年   82篇
  2007年   81篇
  2006年   94篇
  2005年   72篇
  2004年   71篇
  2003年   65篇
  2002年   51篇
  2001年   55篇
  2000年   52篇
  1999年   63篇
  1998年   119篇
  1997年   134篇
  1996年   122篇
  1995年   86篇
  1994年   100篇
  1993年   105篇
  1992年   40篇
  1991年   48篇
  1990年   44篇
  1989年   65篇
  1988年   76篇
  1987年   56篇
  1986年   64篇
  1985年   48篇
  1984年   31篇
  1983年   21篇
  1982年   31篇
  1981年   38篇
  1980年   21篇
  1979年   24篇
  1978年   20篇
  1977年   31篇
  1976年   24篇
  1975年   9篇
  1974年   15篇
  1970年   7篇
排序方式: 共有2821条查询结果,搜索用时 75 毫秒
1.
Although studies have documented underuse of controller medications and overuse of short-acting inhaled ss(2)-agonist among children with persistent asthma in disadvantaged communities, the persistence of oral ss(2)-agonist use in pediatric practice has not been studied since inhaled short-acting ss(2)-agonists became widespread. We describe medications used to treat asthma among children 3 to 5 years of age at 10 Head Start and other subsidized preschool centers in East and Central Harlem, New York City. We interviewed 149 parents/guardians of children who were identified as having probable asthma based on physician's diagnosis, persistent symptoms, hospitalization, and medication use. We classified 86 of the 149 children (58%) as having current persistent asthma. Only 15 of them (17%) were reported to have used controller medications at least 5 days/week in the last 4 weeks-only 2 of whom used inhaled corticosteroids. By contrast, 53 children (62%) used oral ss(2)-agonist in the last 4 weeks, often (72%) in conjunction with nebulized or inhaled short-acting ss(2)-agonist. Use of oral ss(2)-agonist was associated with more severe symptoms. This study documents the continued widespread use of oral ss(2)-agonist for treatment of children in a low-income community with high prevalence of asthma.  相似文献   
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 authors screened for alcoholism 145 consecutive patients who presented with sexual dysfunction or disorders. Using the Michigan Alcoholic Screening Test (MAST), 29% of the patients scored in the probable alcoholic range. Probable alcoholics were more likely to present without a partner and claimed higher sex drive than nonalcoholic patients. Probable alcoholic males reported less joy and vigor than probable alcoholic females, while the reverse held for the nonalcoholic groups. Blind to the MAST results, the staff made six alcohol-related diagnoses and referred one patient for alcohol treatment. The authors discussed the importance of training faculty and resident staff in the relationship of alcohol abuse associated with psychosexual dysfunctions.  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.
We tested the hypothesis that since the implementation of the prospective payment system (PPS), elderly patients hospitalized for hip fractures receive shorter, less care-intensive hospitalizations and are more frequently institutionalized. In blinded fashion, we reviewed the charts of elderly patients with hip fractures admitted to a municipal hospital from 1981 through 1985. Demographic and clinical characteristics of patients treated before implementation of the PPS were similar to patients treated thereafter. After implementation of the PPS, the mean length of hospitalization fell from 16.6 to 10.3 days, and the mean number of physical therapy sessions received decreased from 9.7 to 4.9. Concomitantly, the proportion of patients discharged to a nursing home increased (21% to 48%), as did the proportion receiving nursing home care at six months after discharge (13% to 39%). This increase in long-term nursing home placement suggests that the quality of care for elderly patients with hip fractures may have deteriorated.  相似文献   
6.
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   
7.
8.
9.
10.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  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