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   5881442篇
  免费   412087篇
  国内免费   13209篇
耳鼻咽喉   84950篇
儿科学   192059篇
妇产科学   161144篇
基础医学   823988篇
口腔科学   176687篇
临床医学   555372篇
内科学   1097456篇
皮肤病学   131414篇
神经病学   477066篇
特种医学   220599篇
外国民族医学   2112篇
外科学   870203篇
综合类   140243篇
现状与发展   18篇
一般理论   2754篇
预防医学   484428篇
眼科学   144466篇
药学   434254篇
  22篇
中国医学   11818篇
肿瘤学   295685篇
  2018年   63732篇
  2017年   48348篇
  2016年   54777篇
  2015年   61719篇
  2014年   87392篇
  2013年   134550篇
  2012年   180495篇
  2011年   192597篇
  2010年   115831篇
  2009年   108432篇
  2008年   179680篇
  2007年   191393篇
  2006年   193028篇
  2005年   187652篇
  2004年   180896篇
  2003年   173724篇
  2002年   168742篇
  2001年   249318篇
  2000年   256818篇
  1999年   218690篇
  1998年   68675篇
  1997年   59880篇
  1996年   58613篇
  1995年   56456篇
  1994年   52320篇
  1993年   49215篇
  1992年   174517篇
  1991年   170806篇
  1990年   166188篇
  1989年   161443篇
  1988年   149238篇
  1987年   147127篇
  1986年   139781篇
  1985年   134764篇
  1984年   102075篇
  1983年   87723篇
  1982年   53086篇
  1981年   47945篇
  1979年   96399篇
  1978年   68597篇
  1977年   58714篇
  1976年   55545篇
  1975年   58978篇
  1974年   71869篇
  1973年   69194篇
  1972年   65495篇
  1971年   61398篇
  1970年   57215篇
  1969年   54529篇
  1968年   50552篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Metoclopramide, a substituted benzamide derivative, was orally administered to a patient with intractable hiccups. Dysphoria, akathisia, depressed mood with suicidal ideation, insomnia, racing thoughts, and labile affect were seen following the administration of metoclopramide. The episode met criteria for an organic affective syndrome. It is suggested that the mental status of patients undergoing metoclopramide therapy be monitored, since these symptoms have not been previously reported.  相似文献   
992.
Horner's syndrome or oculosympathetic paralysis is not an uncommon finding in patients with head and neck neoplasms. While in most cases the syndrome is easily established at the bedside, it can be confirmed and topographically defined as a central, preganglionic, or postganglionic lesion through sequential pharmacologic testing. The importance of such localization lies in differentiating neoplasia vs. a benign condition as the cause of the syndrome. Such variants as congenital Horner's, an alternating Horner's, and a pseudo-Horner's syndrome are discussed in regard to their differential features.  相似文献   
993.
In vitro studies established that neither cloth nor disposable diapers demonstrably contributed to the growth of Escherichia coli, Proteus vulgaris, Staphylococcus aureus, or Candida albicans when urine was present as a growth medium. In a clinical study of 166 children, the microbial skin flora of children with atopic dermatitis was compared with the flora of children with normal skin to determine the influence of diaper type. No biologically significant differences were detected between groups wearing disposable or cloth diapers in terms of frequency of isolation or log mean recovery of selected skin flora. Repeated isolation of S. aureus correlated with atopic dermatitis. The log mean recovery of S. aureus was higher in the atopic groups. The effects of each diaper type on skin microflora were equivalent in the normal and atopic populations.  相似文献   
994.
995.
BACKGROUND: The role of atopy in the evolution to chronic obstructive disease remains controversial. AIM: We aimed to assess the association between individual sensitization to common allergens and lung function. METHOD: We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis. RESULTS: Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR. CONCLUSION: We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas.  相似文献   
996.
A 28-year-old male patient diagnosed with Becker muscular dystrophy (BMD)-associated cardiomyopathy was successfully bridged to transplantation with the Cardiowest total artificial heart. Dramatic improvement of muscular functional status occurred following transplantation.  相似文献   
997.
998.
999.
1000.
Because both metabolic (Met Acid) and respiratory acidosis (Resp Acid) have diverse effects on mineral metabolism, it has been difficult to establish whether acidosis directly affects parathyroid hormone (PTH) secretion. Our goal was to determine whether acute Met Acid and Resp Acid directly affected PTH secretion. Three groups of dogs were studied: control, acute Met Acid induced by HCl infusion, and acute Resp Acid induced by hypoventilation. EDTA was infused to prevent acidosis-induced increases in ionized calcium, but more EDTA was needed in Met Acid than in Resp Acid. The PTH response to EDTA-induced hypocalcemia was evaluated also. Magnesium needed to be infused in groups receiving EDTA to prevent hypomagnesemia. The half-life of intact PTH (iPTH) was determined during hypocalcemia when PTH was measured after parathyroidectomy. During normocalcemia, PTH values were greater (p < 0.05) in Met Acid (92 +/- 19 pg/ml) and Resp Acid (77 +/- 22 pg/ml) than in controls (27 +/- 5 pg/ml); the respective pH values were 7.23 +/- 0.01, 7.24 +/- 0.01, and 7.39 +/- 0.02. The maximal PTH response to hypocalcemia was greater (p < 0.05) in Met Acid (443 +/- 54 pg/ml) than in Resp Acid (267 +/- 37 pg/ml) and controls (262 +/- 48 pg/ml). The half-life of PTH was greater (p < 0.05) in Met Acid than in controls, but the PTH secretion rate also was greater (p < 0.05) in Met Acid than in the other two groups. In conclusion, (1) both acute Met Acid and Resp Acid increase PTH secretion when the ionized calcium concentration is normal; (2) acute Met Acid may increase the bone efflux of calcium more than Resp Acid; (3) acute Met Acid acts as a secretogogue for PTH secretion because it enhances the maximal PTH response to hypocalcemia.  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