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   2761篇
  免费   234篇
  国内免费   5篇
耳鼻咽喉   21篇
儿科学   101篇
妇产科学   43篇
基础医学   271篇
口腔科学   30篇
临床医学   287篇
内科学   766篇
皮肤病学   51篇
神经病学   268篇
特种医学   145篇
外国民族医学   1篇
外科学   446篇
综合类   54篇
预防医学   195篇
眼科学   24篇
药学   173篇
中国医学   3篇
肿瘤学   121篇
  2023年   12篇
  2022年   27篇
  2021年   40篇
  2020年   31篇
  2019年   56篇
  2018年   58篇
  2017年   58篇
  2016年   44篇
  2015年   90篇
  2014年   95篇
  2013年   118篇
  2012年   149篇
  2011年   140篇
  2010年   117篇
  2009年   88篇
  2008年   121篇
  2007年   116篇
  2006年   137篇
  2005年   86篇
  2004年   74篇
  2003年   78篇
  2002年   80篇
  2001年   73篇
  2000年   70篇
  1999年   74篇
  1998年   55篇
  1997年   29篇
  1996年   43篇
  1995年   37篇
  1994年   35篇
  1993年   48篇
  1992年   70篇
  1991年   53篇
  1990年   53篇
  1989年   68篇
  1988年   63篇
  1987年   40篇
  1986年   43篇
  1985年   46篇
  1984年   25篇
  1983年   40篇
  1982年   14篇
  1981年   15篇
  1980年   17篇
  1979年   28篇
  1978年   11篇
  1977年   13篇
  1976年   9篇
  1974年   10篇
  1957年   10篇
排序方式: 共有3000条查询结果,搜索用时 15 毫秒
1.
2.
3.
10 patients with CLL and 2 with CML were treated with gradually increasing doses of 1 alpha(OH)D3, up to 4 micrograms daily during 6 wk. 3 patients with preleukemia and 1 with myelofibrosis were treated with 2 micrograms daily of 1 alpha(OH)D3 for a prolonged period up to 17 wk. The treatment with 1 alpha (OH)D3 did not result in changes of disease parameters in any of the patients under study. Receptor studies for 1,25(OH)2D3 were performed in 8 CLL patients and revealed only 1 patient with increased specific receptor binding capacity. The maximum tolerable dose of 1 alpha(OH)D3 varied individually, but was in the range of 2-4 micrograms daily.  相似文献   
4.
Two cases are presented in which the cause of small-bowel obstruction was enterolith originating in jejunal diverticula.  相似文献   
5.
6.
7.
Objective: The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods: This is a cross‐sectional study, utilising a survey carried out in primary health care clinics (PHCs) in Al‐Ain, United Arab Emirates (UAE). A multistage stratified sampling design was used and a representative sample of 1304 UAE nationals aged 18–65 years who attended PHC clinics for any reason were included and 1103 (84.5%) subjects agreed to participate and responded to the questionnaire during a period from June 2001 to January 2002. A specially designed questionnaire with three parts was used for the data collection: socio‐demographic information of the studied subjects, modified version of the Roland‐Morris scale for evaluating back‐related functional disability and SCL‐90 R for depression and somatization subscales was used to assess depressive and somatic symptoms. Results: Of the total number of subjects surveyed (1103), 586 (53.1%) were men and 517 (46.9%) women. The mean age was 34.9 ± 13.4 years for men and 33.5 ± 11.8 years for women. The prevalence of LBP in the studied subjects was 64.7% (95% CI, 60.7–68.5] with 46.7% among men and 53.3% among women. There were a significant differences between the subjects with LBP and without LBP with respect to gender (P < 0.001), body mass index (BMI) (P < 0.001), occupational status (P < 0.001) and living environment (P = 0.016). Functional disability was higher in patients with LBP. Young patients in aged 15–34 years, patients with preparatory/secondary educational level and students showed higher depressive symptoms. A similar pattern was found in patients with somatic symptoms. Factor analysis revealed a strong association between depression and somatization in LBP patients. Conclusions: Functional disability was higher in with LBP. Furthermore, symptoms of depression and somatization are prevalent among LBP patients.  相似文献   
8.
The purpose of this study was to investigate whether men employed in the metal industry have sperm of poorer quality than men in other types of work. A postal questionnaire was sent to men employed in the metal industry, certain other types of nonmetal industries, and other types of employment in which the factors suspected to influence sperm quality were not present. By means of this questionnaire survey, it was hoped to define the possible influences of the work environment on sperm quality. Out of the total of 3,119 men included in the investigation, 2,517 (81%) filled out the questionnaire satisfactorily. Semen analysis was performed for all 3,119 men. There was a greater risk for poor sperm quality among welders than among men not employed in welding. The risk for poor sperm quality was increased for those welders who worked with stainless steel. Welding in general, and specifically with stainless steel, is connected with a risk of reduced sperm quality.  相似文献   
9.
The community-based course presented is a longitudinal course running through four semesters in the Faculty of Medicine, University of Gezira, Sudan. Students combine their regular work in primary health care centres with attachments to a number of families in Wad Medani town. They continue to visit these families regularly throughout their entire medical course with the aim of studying them and helping them with some of their medical and psychosocial problems.  相似文献   
10.
Various types of phenothiazines were examined for antibacterial effect on 61 Gram-positive and Gram-negative bacterial strains in vitro. The investigated phenothiazines were two neuroleptic drugs, fluphenazine and chlorpromazine, and two antihistaminic drugs, alimemazine and promethazine. All four drugs have antibacterial effects in vitro, the phenothiazines being more potent against the Gram-positive microorganisms. The antibacterial potency of the drugs was measured as IC50: Fluphenazine 29 microM (15 micrograms/ml), alimemzaine 49 microM (37 micrograms/ml), promethazine 88 microM (28 micrograms/ml) and chlorpromazine 92 microM (29 micrograms/ml). The antibacterial potency of the drugs was linked neither to the neuroleptic nor the antihistaminic potency of the drugs, which is in agreement with results of earlier stereoisomeric investigations. Thus, the known phenothiazines may represent a pool of potentially new antimicrobial drugs. A therapeutic application of these results, however, requires additional in vitro an in vivo testing in an animal model. The bacterial model might be of value as a model system in the study of the interaction of neuropharmacological agents and other membrane active compounds on biological membranes.  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