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   1315052篇
  免费   92739篇
  国内免费   2064篇
耳鼻咽喉   18706篇
儿科学   45304篇
妇产科学   35579篇
基础医学   186148篇
口腔科学   34441篇
临床医学   114250篇
内科学   263917篇
皮肤病学   28386篇
神经病学   103567篇
特种医学   52229篇
外国民族医学   666篇
外科学   200201篇
综合类   27397篇
现状与发展   1篇
一般理论   426篇
预防医学   97843篇
眼科学   28957篇
药学   96883篇
  30篇
中国医学   2466篇
肿瘤学   72458篇
  2018年   13630篇
  2017年   10403篇
  2016年   11380篇
  2015年   12836篇
  2014年   17805篇
  2013年   27296篇
  2012年   37643篇
  2011年   39832篇
  2010年   23764篇
  2009年   22743篇
  2008年   38322篇
  2007年   41215篇
  2006年   41412篇
  2005年   40384篇
  2004年   39457篇
  2003年   38312篇
  2002年   37551篇
  2001年   64214篇
  2000年   66679篇
  1999年   56650篇
  1998年   15536篇
  1997年   14118篇
  1996年   14469篇
  1995年   13747篇
  1994年   13040篇
  1993年   12071篇
  1992年   44749篇
  1991年   43641篇
  1990年   42375篇
  1989年   40246篇
  1988年   37034篇
  1987年   36357篇
  1986年   33770篇
  1985年   32433篇
  1984年   24402篇
  1983年   20504篇
  1982年   12027篇
  1981年   10960篇
  1980年   9809篇
  1979年   21490篇
  1978年   14989篇
  1977年   12711篇
  1976年   11800篇
  1975年   12741篇
  1974年   14761篇
  1973年   14188篇
  1972年   13007篇
  1971年   11782篇
  1970年   11081篇
  1969年   10055篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
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   
102.
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   
103.
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   
104.
105.
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   
106.
107.
108.
109.
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   
110.
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