全文获取类型
收费全文 | 205篇 |
免费 | 12篇 |
专业分类
各国政治 | 5篇 |
工人农民 | 26篇 |
世界政治 | 9篇 |
外交国际关系 | 1篇 |
法律 | 127篇 |
中国政治 | 2篇 |
政治理论 | 45篇 |
综合类 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 6篇 |
2015年 | 9篇 |
2014年 | 9篇 |
2013年 | 24篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 11篇 |
2009年 | 8篇 |
2008年 | 10篇 |
2007年 | 5篇 |
2006年 | 5篇 |
2005年 | 10篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 6篇 |
2000年 | 5篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有217条查询结果,搜索用时 140 毫秒
211.
Vivienne Heaton M.Sc. Colin Moffatt Ph.D. Tal Simmons Ph.D. 《Journal of forensic sciences》2014,59(3):676-682
Numerous Calliphoridae species have been observed to form larval aggregations during the feeding stage of development, resulting in localized increases in temperature. This study investigates the relationship between maggot numbers in a mass and heat generation. Single‐species aggregations (Lucilia sericata) of various sizes (50–2500 individuals) were reared in the laboratory at a constant ambient temperature of 22°C. Internal mass temperatures were recorded every 5 min throughout the feeding stage of development. Results showed that mass temperatures increased with mass numbers (p‐value < 0.001), ranging from 2.5 to 14°C above ambient. A minimum mass size of 1200 produced overall temperatures that were significantly warmer than ambient, diverging away from 22°C after c. 26 h. These results indicate that the microclimate of a mass has the potential to differ significantly from ambient, which may be influencing larval development rates and should therefore be factored into mPMI estimates to increase accuracy. 相似文献
212.
Cassandra L. Kisiel Tracy Fehrenbach Elizabeth Torgersen Brad Stolbach Gary McClelland Gene Griffin Kristine Burkman 《Journal of family violence》2014,29(1):1-14
Patterns of trauma exposure and symptoms were examined in a sample of 16,212 children in Illinois child welfare. Data were collected on trauma histories, child and caregiver needs and strengths, and analyzed in light of the proposed Developmental Trauma Disorder diagnostic criteria. Youth exposed to both interpersonal violence and attachment-based (“non-violent”) traumas within the caregiving system had significantly higher levels of affective/physiological, attentional/behavioral, and self/relational dysregulation in addition to posttraumatic stress symptoms compared to youth with either type of trauma alone or in relation to other trauma experiences. These complexly traumatized children exhibited higher levels of functional impairment and were more likely to have placement disruptions and psychiatric hospitalizations. Findings suggest a developmental trauma framework can more adequately capture the spectrum of needs of these multiply traumatized youth than existing diagnostic formulations. Utilizing this framework for assessment, treatment planning, and intervention can lead to more targeted and effective services for these children. 相似文献
213.
Sarah D. Lynne-Landsman Julia A. Graber Tracy R. Nichols Gilbert J. Botvin 《Journal of youth and adolescence》2011,40(1):48-58
The theory of sensation seeking has conceptualized this construct as a stable personality trait associated with a variety
of problem behaviors. Reckless behavior theory posits that increases in reckless behavior during adolescence can be attributed,
in part, to increases in sensation seeking. This study evaluated patterns of stability and change in sensation seeking among
868 urban, minority youth (53% female), followed longitudinally across middle school (6th–8th grades). Group-based trajectory
analysis identified a stable low group (20%), a moderate increasing group (60%), and a stable high group (20%) each of which
demonstrated unique associations with changes in problem behaviors. Stable low sensation seekers reported consistently low
levels of aggression, delinquency, and substance use across middle school. Moderate increasing sensation seekers reported
significant increases in these risk behaviors over time from levels near zero in the 6th grade. Stable high sensation seekers
reported high, stable levels of aggression and delinquency upon entry into middle school as well as significant increases
in substance use across middle school. These results lend support to both theories and highlight a need for caution when categorizing
adolescents as high or low sensation seekers. 相似文献
214.
Jonathan Goldner Tracy L. Peters Maryse H. Richards Steven Pearce 《Journal of youth and adolescence》2011,40(2):174-186
This study examined protective and risky companionship and locations for exposure to community violence among African American
young adolescents living in high crime, urban areas. The Experience Sampling Method (ESM), an in vivo data collection method,
was employed to gather information from 233 students (62% female) over 3 years, beginning in the 6th grade. Questionnaire
variables of exposure to community violence were regressed onto ESM companionship and location variables, cross-sectionally
and longitudinally, separately for boys and girls. At different points, time spent with parents, in school, and outside in
private space was associated with less exposure to violence for boys and girls, while time spent with girls was protective
for boys. In addition, time spent outside in public and with older peers was associated with increased risk for boys and girls.
These findings are discussed in relation to previous and potential future research, and to strategies to prevent exposure
to community violence. 相似文献
215.
Adolescence heralds a unique period of vulnerability to depressive symptoms. This longitudinal study examined relational victimization in adolescents?? peer relationships as a unique predictor of depressive symptoms among a primarily (85%) Caucasian sample of 540 youth (294 females) concurrently and across a 6-year period. The moderating effects of emotional support received from mothers, fathers, and peers on the association between relational victimization and adolescents?? depressive symptoms were also investigated. Findings revealed that adolescents who were relationally victimized consistently had higher depressive symptoms than their non-victimized peers. However, high levels of emotional support from fathers buffered this relationship over time. Emotional support from mothers and peers also moderated the longitudinal relationship between relational victimization and depressive symptoms, with high levels of support predicting increases in adolescents?? symptoms. Relational victimization presents a clear risk for depressive symptoms in adolescence, and emotional support may serve either a protective or vulnerability-enhancing role depending on the source of support. 相似文献
216.
217.
Wyman JF Dean DE Yinger R Simmons A Brobst D Bissell M Silveira F Kelly N Shott R Ohr J Howard R Lewis B 《Journal of forensic sciences》2011,56(3):694-699
Drug levels in decomposed individuals are difficult to interpret. Concentrations of 16 drugs were monitored in tissues (blood, brain, liver, kidney, muscle, and soil) from decomposing pigs for 1 week. Pigs were divided into groups (n = 5) with each group receiving four drugs. Drug cocktails were prepared from pharmaceutical formulations. Intracardiac pentobarbital sacrifice was 4 h after dosing, with tissue collection at 4, 24, 48, 96, and 168 h postdosing. Samples were frozen until assay. Detection and quantitation of drugs were through solid phase extraction followed by gas chromatograph/mass spectrometer analysis. Brain and kidneys were not available after 48 h; liver and muscle persisted for 1 week. Concentration of drugs increased during decomposition. During 1 week of decomposition, muscle showed average levels increasing but concentrations in liver were increased many fold, compared to muscle. Attempting to interpret drug levels in decomposed bodies may lead to incorrect conclusions about cause and manner of death. 相似文献