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   14016篇
  免费   150篇
各国政治   434篇
工人农民   1263篇
世界政治   635篇
外交国际关系   508篇
法律   8258篇
中国政治   53篇
政治理论   2997篇
综合类   18篇
  2021年   46篇
  2020年   73篇
  2019年   113篇
  2018年   1392篇
  2017年   1316篇
  2016年   1136篇
  2015年   132篇
  2014年   142篇
  2013年   631篇
  2012年   333篇
  2011年   1051篇
  2010年   1122篇
  2009年   709篇
  2008年   894篇
  2007年   835篇
  2006年   149篇
  2005年   196篇
  2004年   328篇
  2003年   268篇
  2002年   133篇
  2001年   314篇
  2000年   283篇
  1999年   198篇
  1998年   90篇
  1997年   93篇
  1996年   75篇
  1995年   83篇
  1994年   75篇
  1993年   41篇
  1992年   123篇
  1991年   139篇
  1990年   131篇
  1989年   127篇
  1988年   115篇
  1987年   126篇
  1986年   100篇
  1985年   96篇
  1984年   106篇
  1983年   92篇
  1982年   62篇
  1981年   75篇
  1980年   35篇
  1979年   80篇
  1978年   50篇
  1977年   34篇
  1975年   38篇
  1974年   49篇
  1973年   54篇
  1972年   39篇
  1971年   34篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
  相似文献   
882.
Of the fifty-seven cases of cot death studied two-thirds were younger than 3 months, which is also the peak age of infantile hypoglycaemia. Findings from routine necropsy and histology were scarce; in eleven cases they could be regarded as potentially fatal. About half of the infants had had a mild virus-type infection approximately one week before death. Special attention was paid to endocrine pancreas. Insulitis or lymphocytes in the septa were discovered in twelve cases. Hyperplasia of the islets of Langerhans was a common observation; the hyperplasia being either nesidioblastosis-like with clusters of islets around ducti, or diffuse. The average proportion of islet tissue in the whole pancreas parenchyma was around 5% in infants aged 1–6 months, the percentage being significantly greater than in age-matched controls (4.3%). The pancreatic insulin content was also higher in the cot death cases. Serum insulin values were low (mean 4.8 ± 1.2 μU/ml) in cot deaths; in the controls they were twice as high (mean 11.6 ± 1.6 μU/ml) (p < 0.005). The cause of death in this group of cot deaths could thus be (congenital?) hyperplasia of the islets, possibly combined with a lesion in the B-cells caused by a virus. The mechanism of death would be hypoglycaemia.  相似文献   
883.
884.
885.
14 fresh cadavers of adult persons were placed with the head or body tilted in atypical positions 3 to 65 hours after death. The persons concerned were neither asphyxiated nor had they suffered cranial trauma. Hypostasis in the head and neck occurred more rapidly and intensively the deeper the cranial parts of the body were placed. In the simulated cadaver positions, artificial ecchymoses were observed in only a few places, mainly in the eyelids, the conjunctiva, the galea and the temporal muscles except when the head was vertically downwards. Just as with the postmortem haematomas, the hypostatic settling to the plane of the heart was decisive.  相似文献   
886.
887.
888.
889.
Case report. A 82 year old woman died 80 min after accidental ingestion of 5 mg beta-methyl-digoxin. The autopsy and the histological examination revealed non-specific alterations due to shock and preexisting coronary heart disease. Digoxin levels in various fluids and tissues were estimated by radioimmunoassay: bloodplasma 20--25 ng/ml, liquor 10--13 ng/ml, liver 100--110 ng/g, kidney 130--145 ng/g; the gastric fluid contained 0,6 mg. Forensic aspects of glycosid-intoxication, especially of the varying concentrations in different tissues, are discussed.  相似文献   
890.
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