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   16591篇
  免费   514篇
各国政治   507篇
工人农民   701篇
世界政治   1063篇
外交国际关系   520篇
法律   10826篇
中国共产党   34篇
中国政治   170篇
政治理论   3112篇
综合类   172篇
  2021年   94篇
  2020年   225篇
  2019年   234篇
  2018年   326篇
  2017年   392篇
  2016年   423篇
  2015年   329篇
  2014年   366篇
  2013年   1451篇
  2012年   395篇
  2011年   445篇
  2010年   358篇
  2009年   412篇
  2008年   493篇
  2007年   540篇
  2006年   525篇
  2005年   454篇
  2004年   458篇
  2003年   421篇
  2002年   382篇
  2001年   627篇
  2000年   576篇
  1999年   460篇
  1998年   234篇
  1997年   178篇
  1996年   204篇
  1995年   180篇
  1994年   200篇
  1993年   182篇
  1992年   323篇
  1991年   380篇
  1990年   328篇
  1989年   329篇
  1988年   335篇
  1987年   325篇
  1986年   339篇
  1985年   327篇
  1984年   267篇
  1983年   282篇
  1982年   193篇
  1981年   210篇
  1980年   165篇
  1979年   194篇
  1978年   160篇
  1977年   132篇
  1976年   115篇
  1975年   108篇
  1974年   117篇
  1973年   132篇
  1971年   94篇
排序方式: 共有10000条查询结果,搜索用时 974 毫秒
921.
922.
923.
924.
An intoxication following administration of morphine, tramadol and atracurium in a suicide case is reported. The route of administration and the amount of the particular drug were known from the investigation of the death scene and the findings of the postmortem examination. Tramadol was present in the gastric contents as well as in blood, liver, kidney and brain samples, whereas the drug could not be detected in muscle. All body fluids and tissues investigated contained morphine as well as its 3- and 6-glucuronides with the exception of muscle tissue. The concentrations of morphine and its glucuronide metabolites were determined by LC/MS following solid phase extraction. Interestingly, the concentration of M6G in brain, liver and kidney were close to the concentration of M3G in the particular tissue. This phenomenon might be explained by a preferential hydrolysis of M3G or by a preferential formation of M6G postmortem. Measurement of morphine and M6G in femoral blood and cerebrospinal fluid may be a useful indicator in rapid deaths.  相似文献   
925.
After surgical treatment of an inguinal hernia, a 26-year-old male was discharged from hospital with a well healing surgical wound. Four weeks later he was admitted again with a major localized painful swelling of the soft tissues, whereas the clinical examination revealed no further local or systemic signs of inflammation. The immediate operation disclosed no abscess formation, but a large colliquation necrosis of the subcutaneous tissue with an outstanding petroleum-like odour. On toxicological examination of the necrotic tissue, a respective petroleum distillate was found. The patient was confronted with the suspicion of having injected the petroleum preparation himself to prolong the wound healing and finally admitted the self-mutilating behaviour. The pathophysiology, clinical history and morphological findings are discussed in comparison with case reports of chemically induced self-mutilation.  相似文献   
926.
927.
928.
A method is presented for the numerical analysis of sex differences in size and shape of the proximal humeral outlines using elliptical Fourier functions (EFFs). A skeletal sample consisting of right and left humeri pairs of 69 individuals, 36 males and 33 females, was used. The proximal superior view in the plane of the proximo-distal axis of each humerus was photographed and then 54 boundary points were located on the two-dimensional outline tracings. These points were digitized and used to compute EFFs with 27 harmonics. From the EFFs, a set of expected points on the proximal humeral outline was generated using the centroid as an origin. Superimposition of the male and female outlines on this centroid provided a detailed picture of the relative sex differences in size and shape with respect to that center. The bounded area of the proximal humeral outline showed statistically significant sex differences. Additionally, statistical results of the amplitudes derived from the "area-standardized" EFFs and visual assessments of the mean outline plots indicated significant sex differences in shape of the proximal humeral outlines. Focusing on localized regional differences, the greater tubercle was located more postero-medially and the lesser tubercle was located more anteriorly in the males compared to the females. Sex determinations from the proximal humeri were also examined with discriminant functions based on the amplitudes, which represent shape characteristics of the outline, and the hounded area. Using a cross-validation method, predictions of the percentages of cases correctly classified with the discriminant functions were ranged from 92.8% to 95.7% for the right and left humeral data. These results suggest that differences in size and shape of the proximal humeral outlines may be better predictors of sex when compared with conventional measurements of the humerus.  相似文献   
929.
Recent criminal acts in the United Kingdom, United States and other countries have demonstrated the dangers to public safety from the criminal use of improvised explosives on a large scale. Four sets of trials were carried out over four years, partly in collaboration with the United States Federal Bureau of Investigation, involving the firing of large bombs, mostly fertilizer based. The principal objectives of the firings were to measure the physical effects of the explosions upon objects representative of those that would be found at a real bomb scene and to recover any chemical traces deposited on these objects. The results are intended for use as an aid in determining the approximate size and type of an explosive employed in a terrorist attack. This paper describes the background behind the trials, the procedures for preparation of witness materials and charges, and the collection and analysis of physical and chemical evidence.  相似文献   
930.
Population genetics of nine STR loci in two populations from Brazil   总被引:2,自引:0,他引:2  
The Short Tandem Repeats (STRs) D3S1358, HUMvWA31/A, HUMFIBRA/FGA, D8S 1179, D2S11, D18S51, D5S818, D13S317, and D7S820 were studied in two Brazilian populations (from Amazonia and S. Paulo) using the "AmpF1 STR Profiler Plus PCR Amplification Kit." The nine loci showed a combined discrimination power greater than 0.9999999999 and a chance of exclusion of 0.9999.  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