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   28455篇
  免费   2119篇
  国内免费   106篇
耳鼻咽喉   390篇
儿科学   872篇
妇产科学   592篇
基础医学   3972篇
口腔科学   1008篇
临床医学   3428篇
内科学   5868篇
皮肤病学   472篇
神经病学   2680篇
特种医学   672篇
外科学   3283篇
综合类   247篇
一般理论   14篇
预防医学   2959篇
眼科学   699篇
药学   1719篇
中国医学   91篇
肿瘤学   1714篇
  2023年   309篇
  2022年   566篇
  2021年   1127篇
  2020年   626篇
  2019年   964篇
  2018年   1089篇
  2017年   794篇
  2016年   824篇
  2015年   948篇
  2014年   1229篇
  2013年   1541篇
  2012年   2366篇
  2011年   2466篇
  2010年   1230篇
  2009年   1102篇
  2008年   1837篇
  2007年   1702篇
  2006年   1602篇
  2005年   1485篇
  2004年   1279篇
  2003年   1155篇
  2002年   1083篇
  2001年   212篇
  2000年   165篇
  1999年   148篇
  1998年   210篇
  1997年   141篇
  1996年   109篇
  1995年   94篇
  1994年   96篇
  1993年   85篇
  1992年   114篇
  1991年   95篇
  1990年   103篇
  1989年   71篇
  1988年   85篇
  1987年   113篇
  1986年   107篇
  1985年   92篇
  1984年   93篇
  1983年   89篇
  1982年   92篇
  1981年   77篇
  1980年   60篇
  1979年   72篇
  1978年   52篇
  1976年   50篇
  1974年   53篇
  1973年   44篇
  1972年   48篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
41.
The aim of this study was to evaluate corneal innervation in soft contact lens wearers using the Tomey Confoscan confocal microscope (40x/0.75 objective lens). Three distinct age- and sex-matched subject groups were involved, including extended soft (hydrogel and silicone-hydrogel) contact lens wearers, overnight soft (hydrogel) contact lens wearers, and non contact lens wearers. A number of variables were objectively measured, subjectively evaluated, or graded in order to investigate the distribution and morphology of corneal nerves. For most of the evaluated parameters, no statistically significant differences were found. However, qualitative observations showed noticeable differences in corneal nerve appearance among the different subject groups; the degree of corneal oedema was suggested as the main causative factor. In conclusion, neither the short-term (overnight wear) nor the long-term (12-month extended wear) soft contact lens wear appeared to affect the morphology and/or distribution of corneal nerves as viewed with confocal microscopy.  相似文献   
42.
43.
BACKGROUND: The objective of this study was to evaluate the relationship between food allergy and asthma morbidity in adults. METHODS: We interviewed a cohort of persistent asthmatics from an inner-city clinic. Allergies to food were assessed by patient report of convincing symptoms of acute allergic reactions. Outcome variables included health resource utilization and medication use. RESULTS: The prevalence of allergy to fish, peanut, tree-nut, shellfish, and seed allergies were 3%, 3%, 3%, 13%, and 1%. Patients with allergies to > 1 food had increased asthma hospitalizations, ED visits, and use of oral steroids (p < 0.05 for all comparisons). Specifically, allergy to fish was associated with a greater risk of health resource utilization and increased frequency of oral steroid use (p < or = 0.03 for all comparisons). CONCLUSIONS: Self-reported allergy to foods was associated with worse outcomes, suggesting that food allergy may be a risk factor for increased asthma morbidity in adults.  相似文献   
44.
45.
46.
Pradeep J Nathan  Andrew H Kemp  Ben J Harrison 《Neuropsychopharmacology》2003,28(7):1383; author reply 1384-1383; author reply 1385
  相似文献   
47.
48.
One of the side effects of cisplatinum-based chemotherapy is the impairment of spermatogenic function. In order to understand the mechanisms responsible for this side effect, the present study examined the short- and long-term effects of five daily injections of 2 mg/kg cisplatinum upon the functional normality of Leydig cells and Sertoli cells in intact adult rats, and their relationship with the status of spermatogenesis. Results of the present study demonstrate that cisplatinum treatment resulted in a progressive but reversible loss of germ cells from the seminiferous epithelium. Although testicular testosterone contents reduced transiently after the adminisration of cisplatinum, these testosterone levels are otherwise sufficient to support complete spermatogenesis. Thus, the cisplatinum-induced germinal regression cannot be accounted for by hypoandrogenism. The testicular ABP contents of the drug-treated rats remained unchanged during the treatment period, decreased transiently 30 days after the treatment, and returned to normal 120 days after treatment. A decrease in epididymal ABP content was also noted 10 and 30 days after the drug treatment. These observations suggest that Sertoli cell functions were affected by cisplatinum treatment. The effects of cisplatinum upon Sertoli cells were further demonstrated by the dose-dependent suppression of the production of ABP, lactate, and estradiol in cultured Sertoli cells. In addition, cisplatinum administration resulted in a reversible decrease in pituitary weights and an irreversible decrease in seminal vesicle weights. These results further demonstrate the toxic effects of cisplatinum upon various aspects of the male reproductive system.  相似文献   
49.
One goal of supportive housing is to enlarge and improve the functioning of the social support networks of residents. The networks of a convenience sample of 42 residents were assessed using scales developed by Barrera. The size of the networks (11.5) was no larger than that reported for similar clients living in other types of community settings but the composition differed. Staff and co-residents appear to partially replace rather than add to family and friends. This is of concern because friends are uniquely important determinants of satisfaction. An association between perceived need for support and network size was also found. These findings suggest some positive influences but also raise questions about unintended negative consequences of living in artificially constructed social environments.When this project was undertaken, Dr. Goering, Janet Durbin, Bill Lancee and Taras Babiak were all members of the Social and Community Psychiatry Section, Clarke Institute. Robert Foster was Executive Director of Regeneration House, Inc., where Susan Boyles is Assistant Executive Director.  相似文献   
50.
The need for adequate preparation for transition for young people with health care needs who require long term follow-up in the adult sector has long been recognised and is a required part of the national service framework for children. The Royal College of Paediatrics and Child Health and the Royal College of Nursing have endorsed this need for improvement in services for adolescents. In 2006 the Department of Health launched guidelines with a wealth of recommendations. Despite these initiatives only slow progress has been made (usually by enthusiasts) and much work is needed to develop good programmes in many specialties, including non-malignant haematology.  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