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   1302343篇
  免费   96401篇
  国内免费   2151篇
耳鼻咽喉   18476篇
儿科学   43235篇
妇产科学   38451篇
基础医学   190110篇
口腔科学   35957篇
临床医学   110703篇
内科学   257117篇
皮肤病学   26980篇
神经病学   101343篇
特种医学   50867篇
外国民族医学   366篇
外科学   201636篇
综合类   27237篇
现状与发展   1篇
一般理论   310篇
预防医学   94419篇
眼科学   30244篇
药学   99767篇
  2篇
中国医学   2623篇
肿瘤学   71051篇
  2018年   12534篇
  2016年   10655篇
  2015年   12288篇
  2014年   16906篇
  2013年   25444篇
  2012年   35322篇
  2011年   37786篇
  2010年   22285篇
  2009年   20931篇
  2008年   36596篇
  2007年   39509篇
  2006年   39958篇
  2005年   39165篇
  2004年   37770篇
  2003年   36561篇
  2002年   35992篇
  2001年   58990篇
  2000年   60397篇
  1999年   51386篇
  1998年   14501篇
  1997年   13008篇
  1996年   13243篇
  1995年   12534篇
  1994年   11922篇
  1993年   11008篇
  1992年   41389篇
  1991年   40759篇
  1990年   40241篇
  1989年   39043篇
  1988年   36394篇
  1987年   35620篇
  1986年   33990篇
  1985年   32405篇
  1984年   24100篇
  1983年   20978篇
  1982年   12480篇
  1981年   11012篇
  1979年   22759篇
  1978年   15946篇
  1977年   13809篇
  1976年   13034篇
  1975年   14254篇
  1974年   16756篇
  1973年   16139篇
  1972年   15367篇
  1971年   14278篇
  1970年   13240篇
  1969年   12760篇
  1968年   11996篇
  1967年   10493篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
991.
A young patient had an auriculo-ventricular block and a distal myopathy with muscle biopsy findings suggestive of inclusion body myositis. What was most unusual was the presence of numerous sarcoplasmic bodies identified as desmin by electron microscopy and immunocytochemistry. The nosological situation of this condition is discussed.  相似文献   
992.
Beta-adrenergic receptor density on T cells from healthy humans is greatest on suppressor cells (CD8+, CD28-) and the effect of catecholamines, secreted by the sympathetic nervous system, predominates on this subset. The sympathetic skin response, a measure of sympathetic nervous system function, is absent in most patients with chronic progressive multiple sclerosis (MS). We measured beta-adrenergic receptor density on suppressor cells, cytotoxic cells, and monocytes from patients with chronic progressive MS and healthy control subjects. Control receptor density on suppressor cells was 2.8 +/- 0.3 fmol/10(6) cells versus a density of 5.1 +/- 0.7 fmol/10(6) cells for patients. Cytotoxic cell (CD8+, CD28+) receptor density was 1.4 +/- 0.4 fmol/10(6) cells in control subjects and 0.9 +/- 0.3 fmol/10(6) cells in the patients. Monocytes displayed beta-adrenergic receptor densities of 2.6 +/- 0.4 fmol/10(6) cells in normal individuals and 2.7 +/- 0.4 fmol/10(6) cells in the patient group. CD8 lymphocyte beta-adrenergic receptor densities in patients with relapsing-remitting and those with stable MS were not different from control values, yet were significantly less than the values for patients with chronic progressive MS. We find that mononuclear cells from healthy control subjects and patients with chronic progressive MS proliferate in response to 200 units/ml of recombinant human interleukin-2 (IL-2) similarly. However, IL-2 treatment increased beta-adrenergic receptor density on normal mononuclear cells, but failed to increase it on mononuclear cells from patients with chronic progressive MS.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
993.
Reports on individual nonbehavioral child and adolescent psychotherapy since 1963 are reviewed. Inclusion criteria required some minimal contrasting group. Forty-three studies were assessed for basic methodological adequacy and main findings. The authors conclude that summary impressions from this body of literature cannot be made due to the magnitude of the flaws in basic psychotherapy research methodology. Suggestions are made regarding the future of child and adolescent psychotherapy research.  相似文献   
994.
995.
Bipolar disorder is a serious mental illness affecting a large number of Americans. While lithium, the treatment of choice for this disorder, is usually effective, a substantial number of individuals with bipolar disorder are not helped by lithium or are intolerant to its side effects. Consequently, investigators are searching for alternative drugs in order to treat lithium-resistant patients. Although a number of alternative drug treatments have been discussed in the literature, only the anticonvulsants carbamazepine and valproate appear to warrant serious consideration at this time. Future research will further define their roles as antimanic agents.  相似文献   
996.
997.
998.
In the processing of the waste products of phosphorus containing fertilizer production, several major health-related factors were identified depending on the industrial site's peculiarities: unfavourable microclimate conditions (both cold and heat), relative temperature differences, noise and vibration caused by the equipment, semi-product's, additives' and finished product's dusts, fluorine- and phosphorus-containing substances' affects and poor illumination. The proposed data were used for health-related improvements in the occupational conditions.  相似文献   
999.
NTS fallout-induced multiple myeloma in Utah.   总被引:1,自引:0,他引:1  
  相似文献   
1000.
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