全文获取类型
收费全文 | 7468篇 |
免费 | 160篇 |
专业分类
各国政治 | 466篇 |
工人农民 | 253篇 |
世界政治 | 536篇 |
外交国际关系 | 296篇 |
法律 | 4644篇 |
中国共产党 | 7篇 |
中国政治 | 59篇 |
政治理论 | 1342篇 |
综合类 | 25篇 |
出版年
2022年 | 34篇 |
2021年 | 56篇 |
2020年 | 105篇 |
2019年 | 137篇 |
2018年 | 231篇 |
2017年 | 202篇 |
2016年 | 221篇 |
2015年 | 157篇 |
2014年 | 170篇 |
2013年 | 741篇 |
2012年 | 206篇 |
2011年 | 209篇 |
2010年 | 182篇 |
2009年 | 215篇 |
2008年 | 267篇 |
2007年 | 283篇 |
2006年 | 274篇 |
2005年 | 194篇 |
2004年 | 214篇 |
2003年 | 171篇 |
2002年 | 167篇 |
2001年 | 348篇 |
2000年 | 317篇 |
1999年 | 212篇 |
1998年 | 91篇 |
1997年 | 88篇 |
1996年 | 60篇 |
1995年 | 58篇 |
1994年 | 57篇 |
1993年 | 39篇 |
1992年 | 128篇 |
1991年 | 146篇 |
1990年 | 137篇 |
1989年 | 132篇 |
1988年 | 121篇 |
1987年 | 129篇 |
1986年 | 106篇 |
1985年 | 101篇 |
1984年 | 98篇 |
1983年 | 87篇 |
1982年 | 60篇 |
1981年 | 80篇 |
1980年 | 35篇 |
1979年 | 75篇 |
1978年 | 47篇 |
1975年 | 38篇 |
1974年 | 51篇 |
1973年 | 57篇 |
1972年 | 40篇 |
1971年 | 34篇 |
排序方式: 共有7628条查询结果,搜索用时 19 毫秒
901.
Four kinds of DNA probes that recognize hypervariable regions (HVR) were studied for parentage testing and individual identification. Allele frequencies and their confidence intervals among unrelated Japanese individuals were obtained. Codominant segregation of the polymorphism was confirmed in family studies. Two a priori probabilities were calculated for each HVR locus: the exclusion probabilities for an alleged father/mother/child trio and for an alleged parent/child duo, and the probabilities of matching of genotypes of two unrelated individuals or two siblings. The ease of availability of the probes and their highly discriminating polymorphic patterns mean they could be very useful for forensic purposes. 相似文献
902.
K J O'Connell H A Frazier M A Clark P J Christenson B T Keyes A Josselson 《Journal of forensic sciences》1988,33(2):410-417
An animal model was designed to evaluate the ability of the standard military flak jacket to protect the kidneys from direct ballistic trauma. Yorkshire swine were anesthetized and their flanks were protected by flak jackets. Ballistic insults ranging from a low-velocity handgun to a high-velocity rifle were evaluated. The results demonstrate that a flak jacket provides adequate protection against low- and mid-velocity projectiles since none of the animals from this group had evidence of internal trauma and because only minor superficial surgical attention would have been required. Survivability in each case was considered to be excellent. The flak jacket failed to provide any protection against several types of high-velocity bullets. These weapons caused severe internal injury to the genitourinary system as well as to other major organ systems. Survival would have been unlikely. 相似文献
903.
Manfred Oehmichen Horst Wiethölter Helmut Grüninger Mira Gencic 《Forensic science international》1983,21(1):43-57
In rabbits, intracerebrally applied erythrocytes can move with the cerebrospinal fluid along connecting pathways between the subarachnoid space and the cervical lymph nodes. This study compares the time dependency for the degradation of intracerebrally injected erythrocytes in the brain as well as in the cervical lymph nodes. Rabbits were killed at various predetermined intervals after the intracerebral erythrocyte injection. Microscopic and histologic examination of the brain and the cervical lymph nodes revealed the following findings: (1) Erythrophages first appeared in the brain 24 h after the injection; siderophages, 4 days after the injection. Siderophages were still demonstrable at the conclusion of the study, i.e. 240 days after the injection. (2) In the cervical lymph nodes erythrophages were first observed 1 h after the injection; siderophages, 9 h after the injection. Only isolated erythrophages and siderophages were found in the lymph nodes 12 days after intracerebral injection of red blood cells. Later on no erythrocytes or siderophages were observed in the lymph nodes. The findings indicate that non-phagocytized red blood cells arriving at the lymph nodes were ingested by local macrophages. The extremely rapid ingestion and digestion of the red blood cells by lymph node macrophages as well as the possible reasons were discussed. 相似文献
904.
905.
An infant fatality following accidental ingestion of ajmaline is described. Ajmaline was determined by thin-layer chromatography and infrared spectrophotometry, and quantitated by high performance liquid chromatography. The ajmaline concentration in blood was 5.5 micrograms/mL. The toxicological data relevant to the interpretation of case findings are presented. 相似文献
906.
907.
908.
909.
910.