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   611706篇
  免费   74809篇
  国内免费   2509篇
耳鼻咽喉   8496篇
儿科学   21239篇
妇产科学   14413篇
基础医学   102508篇
口腔科学   19697篇
临床医学   59500篇
内科学   119250篇
皮肤病学   19333篇
神经病学   50172篇
特种医学   21383篇
外国民族医学   84篇
外科学   92431篇
综合类   12609篇
现状与发展   5篇
一般理论   140篇
预防医学   44906篇
眼科学   13938篇
药学   48436篇
  23篇
中国医学   3394篇
肿瘤学   37067篇
  2021年   5756篇
  2020年   7887篇
  2019年   14690篇
  2018年   15351篇
  2017年   15263篇
  2016年   16259篇
  2015年   16971篇
  2014年   18655篇
  2013年   22418篇
  2012年   18547篇
  2011年   20038篇
  2010年   17892篇
  2009年   13679篇
  2008年   16867篇
  2007年   16712篇
  2006年   16984篇
  2005年   16216篇
  2004年   15510篇
  2003年   14732篇
  2002年   14670篇
  2001年   25344篇
  2000年   26320篇
  1999年   21484篇
  1998年   5879篇
  1997年   5119篇
  1996年   5368篇
  1995年   4914篇
  1992年   15963篇
  1991年   16497篇
  1990年   16583篇
  1989年   15956篇
  1988年   14716篇
  1987年   14548篇
  1986年   13714篇
  1985年   13075篇
  1984年   9679篇
  1983年   8287篇
  1979年   9439篇
  1978年   6871篇
  1977年   5787篇
  1976年   5612篇
  1975年   6404篇
  1974年   7645篇
  1973年   7136篇
  1972年   6967篇
  1971年   6694篇
  1970年   6177篇
  1969年   5892篇
  1968年   5567篇
  1967年   5013篇
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
71.
72.
73.
Formulae for the calculation of the count of microorganisms isolated from natural bacterial biocenoses of a child's body have been derived. The authors suggest a variant of simplified drip method for the computation of microorganism colonies in solid media. The described method helps cut down the nutrient media consumption at least 3-fold and is time-saving.  相似文献   
74.
Perceptual asymmetry on a series of four specially constructed dichotic word tests was found to change as a function of the emotional quality of the words in the tests (P = 0.05). This was most pronounced in the case of positively valued words which produced an increase in asymmetry consistent with facilitated left-hemisphere function (P less than 0.004). Changes in asymmetry with emotion differed as a function of personality characteristics of the subjects, with repressors and high anxious subjects showing an increase with emotion while true low anxious subjects showed a decrease (P less than 0.02). Personality groups also differed in asymmetry on an emotionally neutral test (P less than 0.04) and in changes in asymmetry over time independent of emotion (P less than 0.001). These data suggest that emotion mediated activation of the left hemisphere may facilitate information processing within that hemisphere. Moreover, they indicate that dichotic listening tests may provide a non-invasive and inexpensive method for assessing emotion mediated changes in brain state that are clinically relevant.  相似文献   
75.
76.
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   
77.
78.
79.
Carnitine status in Reye and Reye-like syndromes   总被引:4,自引:0,他引:4  
Fourteen children with the following Reye and Reye-like syndromes were studied to determine each patient's carnitine status: valproate-induced Reye-like attack, ornithine transcarbamylase deficiency, systemic carnitine deficiency, methylmalonic acidemia, and propionic acidemia. Reduced free carnitine and increased serum and urine acylcarnitine levels were found in all patients except for 2 with Reye syndrome, in whom serum creatinine levels were mildly elevated and serum free carnitine levels were not reduced. The renal free carnitine reabsorption rate was reduced in all cases. The free carnitine content of autopsied liver samples were reduced in 2 Reye syndrome patients, 2 OTC deficiency patients, and in a single systemic carnitine deficiency patient. The observed secondary free carnitine deficiency may be a factor in the pathogenesis of Reye and Reye-like syndromes.  相似文献   
80.
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