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   18079篇
  免费   1386篇
各国政治   648篇
工人农民   612篇
世界政治   1319篇
外交国际关系   507篇
法律   13135篇
中国共产党   1篇
中国政治   127篇
政治理论   3007篇
综合类   109篇
  2020年   402篇
  2019年   437篇
  2018年   494篇
  2017年   580篇
  2016年   608篇
  2015年   515篇
  2014年   553篇
  2013年   1794篇
  2012年   426篇
  2011年   530篇
  2010年   651篇
  2009年   620篇
  2008年   443篇
  2007年   450篇
  2006年   548篇
  2005年   406篇
  2004年   388篇
  2003年   412篇
  2002年   359篇
  2001年   707篇
  2000年   599篇
  1999年   493篇
  1998年   229篇
  1997年   195篇
  1996年   178篇
  1995年   198篇
  1994年   207篇
  1993年   175篇
  1992年   341篇
  1991年   359篇
  1990年   338篇
  1989年   374篇
  1988年   328篇
  1987年   312篇
  1986年   320篇
  1985年   348篇
  1984年   317篇
  1983年   310篇
  1982年   232篇
  1981年   211篇
  1980年   189篇
  1979年   235篇
  1978年   163篇
  1977年   142篇
  1976年   120篇
  1975年   113篇
  1974年   131篇
  1973年   121篇
  1972年   93篇
  1971年   104篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
942.
This article uses three perspectives to explain the radical economic and state sector reforms undertaken in New Zealand starting in 1984. We interpret the reforms using a rational-comprehensive perspective, a garbage can perspective and a modified garbage can perspective identified in the work of John Kingdon. With New Zealand as an illustrative case, we explore the conditions under which radical reform is possible, the factors governing the adoption of reforms, and the impact on the reform process of a country's historical and cultural traditions. Our analysis emphasizes the import of a package of ready-made solutions, strong advocates (particularly a well-placed policy entrepreneur) who attach the solutions to a problem, and the existence of a 'window of opportunity' for adoption of the reforms. We conclude with a discussion of the implications of adopting reforms that run counter to a nation's long-established traditions.  相似文献   
943.
Lemonick MD 《Time》2000,156(18):66-70, 73-4
  相似文献   
944.
945.
946.
947.
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   
948.
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   
949.
950.
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   
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