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141.
Here, we present a method of extracting drug residues from fingerprints via Direct Analyte‐Probed Nanoextraction coupled to nanospray ionization–mass spectrometry (DAPNe‐NSI‐MS). This instrumental technique provides higher selectivity and lower detection limits over current methods, greatly reducing sample preparation, and does not compromise the integrity of latent fingerprints. This coupled to Raman microscopy is an advantageous supplement for location and identification of trace particles. DAPNe uses a nanomanipulator for extraction and differing microscopies for localization of chemicals of interest. A capillary tip with solvent of choice is placed in a nanopositioner. The surface to be analyzed is placed under a microscope, and a particle of interest is located. Using a pressure injector, the solvent is injected onto the surface where it dissolves the analyte, and then extracted back into the capillary tip. The solution is then directly analyzed via NSI‐MS. Analyses of caffeine, cocaine, crystal methamphetamine, and ecstasy have been performed successfully.  相似文献   
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Official data maintained by the Florida Department of Juvenile Justice of 16,779 juveniles released from commitment programs to the community or aftercare between July 1, 1998 and June 30, 2000 were examined in this study. No consistent relationship between length of confinement and recidivism was found. The effects of length of stay were mediated based on the risk level of the commitment facility and gender. The length of confinement was only significant for juveniles released from high-risk facilities and male offenders. More research must be conducted to further examine the positive and negative impact of confinement on juvenile re-offending. Future research must include in its analysis the effect of program quality and treatment. Both factors may significantly mediate the relationship between confinement and recidivism.  相似文献   
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Social Justice Research - Students face innumerable stressors, in and outside of schools. Some schools are better able to support students to thrive, individually and collectively, in the midst of...  相似文献   
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School-based extracurricular activity involvement has been associated with lower levels of substance use among adolescents from various populations; however, these associations have only been slightly examined among American Indian (AI) adolescents. Building from various theoretical perspectives, it was hypothesized that AI adolescents’ perceived access to and the intensity (i.e., frequency) of participation in extracurricular activities would be associated with lower substance use and less engagement in risky substance use behaviors (i.e., being drunk or high at school, riding/driving with an intoxicated driver, and selling drugs). The moderating influences of sex, age, reservation residence, and metropolitan status also were examined. Data from the 2010 Arizona Youth Survey were analyzed for 5,701 8th, 10th, and 12th grade AI adolescents (49.1 % female). The expected protective effects of extracurricular participation were demonstrated, such that high levels of perceived availability and intensity of participation consistently predicted low levels of all outcomes. Some of these associations were moderated by one or more demographic factors, with unique patterns emerging for each behavior. Ultimately, the findings suggest that AI adolescents benefit from the availability of extracurricular activities and intensity of participation in them, but the degree of the effect is contingent upon other individual and contextual characteristics.  相似文献   
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Political scientists are keenly interested in how diversity influences politics, yet we know little about how diverse groups of political actors interact. We advance a unified theory of colleague valuation to address this puzzle. The theory explains how minority group size affects how members of a political organization differentially value majority and minority group colleagues, predicting that the effect of preference divergence on individual‐level colleague valuation is greatest when the minority group is smallest. We test this prediction using member‐to‐member leadership political action committee (PAC) contributions in the U.S. House of Representatives. The results obtain strong, albeit not uniform, support for the theory, demonstrating that the gender gap in colleague valuations declines as preference divergence increases in all but one instance. In contrast to conventional wisdom, the theory and evidence indicate that women serving in the U.S. House of Representatives receive less support from men colleagues as their ranks increase.  相似文献   
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Relatively little is known about the degree to which subcomponents of self-regulation change during early to middle adolescence. This study considered familial predictors (maternal/paternal regulatory support, antagonistic parenting, and parent-child closeness) of rank-order change in behavioral, emotional and cognitive regulation and perseverance over one year. N?=?452 adolescents ages 11–16 years and their parents completed questionnaires and parent-child discussion tasks (48.7% male; 69.6% white). Results indicated minimal direct effects of parenting, though maternal and paternal parenting and parent-child closeness exerted small effects that were moderated by prior levels of cognitive regulation and perseverance. Parents may contribute to the development of complex regulatory capacities that mature after foundational emotional and behavioral regulation competencies.  相似文献   
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Sexuality Related Social Support Among Lesbian, Gay, and Bisexual Youth   总被引:1,自引:0,他引:1  
Lesbian, gay, and bisexual (“LGB”) youth may face significant stressors related to their sexual orientation. Few studies, however, have examined youth’s experiences of support for coping with these stressors. The current study compared LGB youth’s perceptions of support for sexuality stress to their support for other types of problems. The links between sexuality stress, sexuality support, and emotional distress were also examined. Ninety-eight LGB youth (ages 18–21, 33% female) rated support from family, heterosexual friends, and sexual minority friends for dealing with problems related, and not related, to their sexuality. From family and heterosexual friends, support for sexuality stress was less available than support for other stressors. Sexual minority friends provided the highest levels of sexuality support. In regression analyses, higher levels of sexuality support related to decreased emotional distress and buffered against the negative effects of sexuality stress on emotional distress. Sexuality support, although less available than other types of support, may be especially relevant to mental health among LGB youth.  相似文献   
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