全文获取类型
收费全文 | 199篇 |
免费 | 7篇 |
专业分类
各国政治 | 7篇 |
工人农民 | 9篇 |
世界政治 | 17篇 |
外交国际关系 | 7篇 |
法律 | 133篇 |
中国政治 | 2篇 |
政治理论 | 24篇 |
综合类 | 7篇 |
出版年
2022年 | 2篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 8篇 |
2017年 | 7篇 |
2016年 | 4篇 |
2015年 | 8篇 |
2014年 | 4篇 |
2013年 | 23篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 4篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 10篇 |
2004年 | 2篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 8篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有206条查询结果,搜索用时 15 毫秒
41.
42.
V C Reeve W B Robertson J Grant J R Soares E G Zimmermann H K Gillespie L E Hollister 《Journal of forensic sciences》1983,28(4):963-971
A pilot study was conducted to ascertain the range of induced hemolyzed blood/serum delta 9-tetrahydrocannabinol (delta 9-THC) concentrations in 58 human subjects. Subjects were tested within 5 min of smoking a delta 9-THC cigarette and then at half-hour intervals to 150 min. The subjects initially demonstrated a broad range of delta 9-THC hemolyzed blood levels, which settled within an hour to levels comparable to those measured in California drivers who had been stopped for impaired driving, arrested, and tested for delta 9-THC. Serum levels, when correlated with performance or roadside sobriety tests, demonstrated a broad range (5 to 183 ng/mL) of delta 9-THC levels and an "adaptation" effect in the subjects' perception of their own impairment. Although this preliminary study was not a double-blind placebo experiment, the overall performance of human subjects demonstrated the "adaptation" effect, which may be a significant factor in making judgments while performing such complex tasks as driving. Also, the effects of the drug extended beyond the period of elevated delta 9-THC blood levels, perhaps because of THC metabolites that may contribute to impairment or the persistence of THC in the central nervous system. This pilot study will lay the groundwork for a program designed to determine the epidemiology and behavior correlates of marijuana use in motorists. 相似文献
43.
44.
45.
46.
47.
The experience of aversive interactions within the family of origin is believed to increase the probability of parental physical child abuse. To test this hypothesis, 375 subjects were given a Childhood History Questionnaire (CHQ) and the Child Abuse Potential (CAP) Inventory. The CHQ contained a series of questions about the presence and frequency of various abusive behaviors and associated sequelae that were received and/or observed before and/or after puberty. The CAP Inventory was used to measure adult physical child abuse potential. As expected, a childhood history of physical abuse was significantly related to adult physical child abuse potential; and, as chronicity increased, so did abuse potential. The experience of physical abuse prior to puberty produced higher abuse scores than the experience of physical abuse after puberty. The study provides preliminary data indicating the childhood experience of a caring adult and / or caring friend moderates adult child abuse potential. 相似文献
48.
49.
Circumstances of criminal activities involving radioactive materials may mean fiber evidence recovered from a crime scene could have been exposed to materials emitting ionizing radiation. The consequences of radiation exposed fibers on the result of the forensic analysis and interpretation is explored. The effect of exposure to 1-1000 kGy radiation doses in natural and synthetic fibers was noticeable using comparative forensic examination methods, such as optical microscopy, microspectrophotometry, and thin-layer chromatography. Fourier transform infrared spectroscopy analysis showed no signs of radiation-induced chemical changes in any of the fiber structures. The outcome of the comparative methods highlights the risk of "false negatives" associated in comparing colors of recovered fibers that may have been exposed to unknown radiation doses. Consideration of such results supports the requirement to know the context, including the environmental conditions, as much as possible before undertaking a forensic fiber examination. 相似文献
50.