全文获取类型
收费全文 | 7980篇 |
免费 | 216篇 |
专业分类
各国政治 | 326篇 |
工人农民 | 273篇 |
世界政治 | 482篇 |
外交国际关系 | 217篇 |
法律 | 5458篇 |
中国共产党 | 1篇 |
中国政治 | 45篇 |
政治理论 | 1326篇 |
综合类 | 68篇 |
出版年
2020年 | 93篇 |
2019年 | 100篇 |
2018年 | 137篇 |
2017年 | 144篇 |
2016年 | 164篇 |
2015年 | 121篇 |
2014年 | 138篇 |
2013年 | 720篇 |
2012年 | 213篇 |
2011年 | 251篇 |
2010年 | 179篇 |
2009年 | 157篇 |
2008年 | 234篇 |
2007年 | 242篇 |
2006年 | 226篇 |
2005年 | 203篇 |
2004年 | 241篇 |
2003年 | 225篇 |
2002年 | 214篇 |
2001年 | 319篇 |
2000年 | 292篇 |
1999年 | 226篇 |
1998年 | 88篇 |
1997年 | 67篇 |
1995年 | 72篇 |
1994年 | 66篇 |
1993年 | 74篇 |
1992年 | 147篇 |
1991年 | 166篇 |
1990年 | 182篇 |
1989年 | 175篇 |
1988年 | 176篇 |
1987年 | 167篇 |
1986年 | 174篇 |
1985年 | 181篇 |
1984年 | 142篇 |
1983年 | 132篇 |
1982年 | 72篇 |
1981年 | 66篇 |
1980年 | 57篇 |
1979年 | 78篇 |
1978年 | 88篇 |
1976年 | 59篇 |
1975年 | 71篇 |
1974年 | 94篇 |
1973年 | 89篇 |
1972年 | 74篇 |
1971年 | 64篇 |
1970年 | 68篇 |
1969年 | 69篇 |
排序方式: 共有8196条查询结果,搜索用时 15 毫秒
951.
M I Okoye D E Congdon W F Mueller 《The American journal of forensic medicine and pathology》1985,6(2):105-124
This report describes certain interesting postmortem findings in the hearts of five subjects who died suddenly, silently, and unexpectedly, and in whom the only significant abnormality at autopsy was asymmetric septal hypertrophy (ASH) of the heart. Deep clefts, cystic faults, and dilated vascular channels were not only seen within the septal myocardium in all the hearts, but also within the left ventricular free walls of two hearts. The septal myocardium and the left ventricular free walls of two hearts and the A-V node and His bundle of one heart demonstrated mural and luminal thrombi of several dilated vascular channels. In another heart, foci of cardiocytic myofibrillar degeneration were seen, especially close to narrowed small coronary vessels. Fetal dispersion and fibrosis of the A-V node and His bundle were evident in one heart. These abnormalities in the conducting system and the ventricular myocardium suggest that the hearts of subjects with ASH are not only excellent anatomic substrates for lethal arrhythmias, but also are bound to be hemodynamically impaired. We believe that conditions such as hypoxia, increased oxygen demand by the heart or abnormal sympathetic stimulus may easily trigger fatal arrhythmias in such individuals, thereby causing sudden death. 相似文献
952.
953.
954.
955.
956.
957.
The current expansion of free political association under glasnost'has focused the political energies of mobilized national movementson demands for republican autonomy. Reform-minded elements inthe Gorbachev leadership have encouraged these movements, seeingthem as counterweights to central governmental bureaucracy.Aspirations for national statehood have reached fullest expressionin the Baltic republics, where the republican parliaments haveexpressed overwhelming support for economic and cultural sovereignty,but such sentiments are voiced by national intelligentsias ineach republic. Moscow has adopted a program of republican decentralizationas a solution to the growing problem of the federal budget deficit,but the implications of republican economic autonomy for thecohesiveness of the federal union are fundamental and far-reaching. 相似文献
958.
J Hiss A Hirshberg D F Dayan J J Bubis M Wolman 《The American journal of forensic medicine and pathology》1988,9(4):310-312
Healing of incised wounds in the backs of mice was studied to establish criteria that would allow the timing of stages during cutaneous wound healing. Starting from day 4 after the incisions were made, three mice were killed every 3 days until day 40. Sections from wounds were stained with hematoxylin-eosin, a reticulin procedure, and picrosirius red. Unstained sections were used for blue autofluorescence. The significance of the findings from the ultraviolet study was limited, but the picrosirius red-polarized light procedure was found to be useful for estimating the age of the repair process as polarization colors of greater wavelengths progressively increased with the age of the lesion. 相似文献
959.
960.