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   1279386篇
  免费   98111篇
  国内免费   2001篇
耳鼻咽喉   18432篇
儿科学   44433篇
妇产科学   35046篇
基础医学   182270篇
口腔科学   33594篇
临床医学   111336篇
内科学   258431篇
皮肤病学   28036篇
神经病学   100414篇
特种医学   51229篇
外国民族医学   660篇
外科学   196477篇
综合类   27068篇
现状与发展   1篇
一般理论   380篇
预防医学   95749篇
眼科学   27930篇
药学   94884篇
  2篇
中国医学   2426篇
肿瘤学   70700篇
  2018年   13157篇
  2017年   9982篇
  2016年   10925篇
  2015年   12391篇
  2014年   17205篇
  2013年   26251篇
  2012年   36092篇
  2011年   38125篇
  2010年   22827篇
  2009年   21834篇
  2008年   36677篇
  2007年   39290篇
  2006年   39560篇
  2005年   38470篇
  2004年   37619篇
  2003年   36463篇
  2002年   35819篇
  2001年   64004篇
  2000年   66507篇
  1999年   56418篇
  1998年   15137篇
  1997年   13757篇
  1996年   14201篇
  1995年   13461篇
  1994年   12769篇
  1993年   11797篇
  1992年   44570篇
  1991年   43477篇
  1990年   42239篇
  1989年   40127篇
  1988年   36908篇
  1987年   36246篇
  1986年   33623篇
  1985年   32284篇
  1984年   24145篇
  1983年   20282篇
  1982年   11726篇
  1981年   10701篇
  1980年   9518篇
  1979年   21347篇
  1978年   14825篇
  1977年   12536篇
  1976年   11695篇
  1975年   12628篇
  1974年   14668篇
  1973年   14124篇
  1972年   12950篇
  1971年   11735篇
  1970年   11053篇
  1969年   10032篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
The sodium, potassium and creatinine contents of three non-consecutive 24-h urine samples collected by 34 selected adult individuals (10 m; 24 f) living in Cork City were determined. The pooled mean 24-h excretion of sodium and potassium in collections adjudged to be complete were 152 mmol and 78 mmol, respectively. There was no significant difference between group average weekday and weekend-day excretion of Na or K, for either males or females. This suggests that weekend 24-h urinary collections, which most subjects find more convenient, are suitable for studies of sodium and potassium intakes of groups. The ratios of intra- to inter-individual variation for 24-h urinary sodium were 1.4 and 2.1 for males and females, respectively. The corresponding ratios for 24-h urinary potassium were 6.6 for males and 4.9 for females. These ratios indicated that there were large individual day-to-day variations in urinary sodium and potassium excretion in this group. It was estimated that a sample size of 35-60 individuals would be required to estimate group mean sodium and potassium intakes by means of single 24-h urine collections.  相似文献   
103.
Vogt-Koyanagi-Harada syndrome and pregnancy   总被引:2,自引:0,他引:2  
Two black women had bilateral anterior and posterior uveitis, nonrhegmatogenous retinal detachments, pleocytosis, headaches, dysacousis, and alopecia. These patients with Vogt-Koyanagi-Harada (VKH) syndrome improved clinically while they were pregnant after the discontinuation of corticosteroid treatment. They developed recurrent symptoms and findings after termination of their pregnancies. We speculate that changes in immunity and humoral constituents during pregnancy account for their remissions. It is important to assess the menstrual history and to avoid pregnancy before initiating steroid treatment for VKH syndrome.  相似文献   
104.
Keloids     
Keloids are benign fibrous growths that result from an abnormal connective tissue response in certain predisposed individuals. Blacks form keloids more often than whites; however, the reason for this racial difference is not known. Trauma, foreign-body reactions, infections, and endocrine dysfunction have all been proposed as precipitating factors. Keloids are found most commonly on the ear lobes, shoulders, upper back, and midchest. They extend past the area of trauma and once present tend to remain stable. Although sometimes pruritic, painful, or tender, they are usually asymptomatic. Histologically, keloids are characterized by thick collagen bundles, abundant mucinous ground substance, few fibroblasts, and few if any foreign-body reactions. Although there have been many therapeutic modalities, most have had limited success. The most commonly used therapeutic approach is a combination of cryotherapy, intralesional steroid injections, surgical excision, and pressure devices.  相似文献   
105.
106.
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status.  相似文献   
107.
108.
109.
110.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben.  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