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941.
Whereas non-suicidal self injury (NSSI) is reported in 13–23% of adolescents and is an increasingly studied topic, there has been little investigation into the pathophysiology behind self-injury. This commentary examines recent research into pain and emotional distress to discuss implications for the manner we should understand, research, and treat NSSI in the future. Research indicates that adolescents may be particularly vulnerable to NSSI behaviors due to neurodevelopmental changes in the processing of distress and pain. Additionally, emotional distress and physical pain neural pathways may have been altered in these individuals, leading to the development of NSSI behaviors during adolescence when changes in ongoing brain development may lead to further emotional dysregulation and poor impulse control. Further studies that directly characterize the relationship between emotional distress and physical pain in adolescence, as well as the neural differences between self-injurers and non-self-injurers, are needed.  相似文献   
942.
In this study we examined the effects of risk factors (perceived neighborhood crime/delinquency problems, neighborhood incivilities) and protective factors (teacher support, family support, peer support) on the school engagement of 123 urban adolescents of color. Age and gender were also examined to determine if different ages (younger or older) or genders (male or female) significantly modified the relationship between the risk factors and school engagement. Results indicated that perceived neighborhood incivilities was uniquely predictive of school engagement. Contrary to hypotheses, different levels of the perceived social support variables did not modify the effects of risky neighborhood conditions on adolescent’s perceived school engagement. Age, but not gender, significantly modified the relationship between perceived family social support and perceived neighborhood crime on adolescents’ reported levels of school engagement. The implications of the results for prevention and intervention programs that address school engagement among early adolescents of color are considered.
Brian P. DalyEmail:
  相似文献   
943.
A large proportion of perinatally HIV-infected (PHIV) children are becoming adolescents and exploring their sexuality. This study explored the prevalence of sexual behaviors (kissing, touching, engaging in oral sex, or having vaginal/anal intercourse) in a sample of predominantly ethnic minority youths (N = 339; 54.1% Black and 30.4% Latino; 51% female; ages 9–16) perinatally exposed to HIV (61% HIV+). Using logistic regression, we tested the association between sexual behavior and HIV status, demographic characteristics, and peer influences regarding sexual behavior. PHIV youth were less likely to be sexually active. Among sexually active youth, PHIV youth were more likely to engage in touching behavior than HIV-negative youth and were less likely to engage in penetrative sex. Youths reporting that a greater number of their peers believed that sexually active boys were “cool” or “popular” were more likely to report sexual behavior. The association between sexual behavior and peers believing sexually active girls were “cool” or “popular” varied by age, gender, and HIV status. Furthermore, friends’ sexual activity was associated with sexual intercourse. Prevention programs should strengthen messages addressing peer norms regarding sexuality, as well as address specific issues related to adolescent HIV.
Claude Ann MellinsEmail:
  相似文献   
944.
Fibromuscular dysplasia is an idiopathic, nonatheromatous, and noninflammatory arterial disease that most commonly affects the renal and carotid arteries. We report a child with subarachnoid and ocular hemorrhage associated with an aneurysm due to fibromuscular dysplasia. Computed tomography following a witnessed collapse revealed diffuse subarachnoid hemorrhage and severe cerebral edema. An autopsy confirmed the radiographic findings and detected bilateral retinal hemorrhages, optic nerve sheath hemorrhages, and a ruptured saccular aneurysm due to focal fibromuscular dysplasia involving the intracranial right vertebral artery. This case documents a fatal subarachnoid hemorrhage in a child with an intracranial saccular aneurysm caused by fibromuscular dysplasia. The associated retinal hemorrhages are easily detected by postmortem monocular indirect ophthalmoscopy.  相似文献   
945.
Performance validity tests (PVTs) effectively detect suboptimal test performance, but cutoff scores for a given test may differ between populations. This research examines how optimal PVT cutoffs differ in a collegiate research population when mental health and clinical conditions are considered. Healthy controls (n = 328) and non-referred students with self-reported clinical conditions (n = 42) were assigned to perform their best while others simulated ADHD symptoms (n = 123). PVT indices were derived from a stand-alone measure (Victoria Symptom Validity Test) and embedded measures (California Verbal Learning Test – Second Edition; Wechsler Adult Intelligence Scale – Fourth Edition, Digit Span). PVT cutoffs with the highest sensitivity, while maintaining adequate specificity, were identified when the control groups were considered together, and when students with reported clinical conditions were considered separately. Mean differences in PVT performances were found between the simulation group and control groups, but not between clinical and nonclinical controls. The optimized cutoffs differed for five of eight PVT indices when all controls were considered together versus the clinical control group, only. When discordance was observed, cutoffs tended to be lower (less stringent) for the non-referred clinical control group. Together, these optimized cutoffs tended to be more stringent than previously established cutoffs. This study suggests that PVT cutoffs may be responsibly altered in a research context in the presence of a clinical condition. Future research should investigate if PVT classification accuracies can be improved in clinical and forensic samples while considering clinical conditions.  相似文献   
946.
947.
ABSTRACT

This paper analyzes the relative roles of cultural and structural factors in the emergence and solidification of taxi driving as an ethnic occupational niche among Ethiopian immigrants in the Washington DC metropolitan area within the wider context of globalization and immigrant integration. An ethnic occupational niche is the concentration and specialization of members of an ethnic group in a particular occupational activity. Using data from the US Census Bureau and in-depth interviews with 25 (male) Ethiopian cab drivers and three Ethiopian cab company owners, it examines the factors that affected the entrance of first-generation Ethiopian immigrants in this occupation since the 1980s. This research demonstrates that mixed embeddedness or the interplay of structural factors such as blocked mobility as well as cultural factors such as the strong social networks that exist among Ethiopian immigrants were important in the induction of new immigrants into taxicab driving. The demographic composition of the Washington metropolitan area and policies of the DC Taxicab Commission that allow for fairly easy entry of new drivers in the taxicab business also facilitated the emergence of this occupational niche.  相似文献   
948.
Terrorist organizations’ physical safe havens continue to shape the terrorist threat to the United States by extending the groups’ longevity and increasing the threat they pose. As a result, eliminating terrorist safe havens has been a key component of U.S. counterterrorism policy since at least 2001. However, some scholars challenged the post-9/11 policy consensus that terrorists find sanctuary in weak states and so-called ungoverned spaces. This article seeks to bridge this gap between scholarship and policy by offering a typology for disaggregating different kinds of terrorist safe havens. Our typology operates on two axes based on host government will (i.e., the host government's posture toward each group with haven inside its borders), as well as government capability, (specifically whether the host government possesses the specific capabilities needed to oust each group). This intersection of will and capability produces three types of havens. We briefly illustrate each type of haven using the exemplar case study of Pakistan—a location often described as an overarching safe haven, but which is actually home to several sanctuaries—and offer policy recommendations for addressing them. A need exists to disaggregate and identify how the United States can approach haven elimination. This typology and the analysis that stems from it offer a starting point for devising such strategies.  相似文献   
949.
Racial discrimination has serious negative consequences for the adjustment of African American adolescents. Taking an ecological approach, this study examined the linkages between perceived racial discrimination within and outside of the neighborhood and urban adolescents’ externalizing and internalizing behaviors, and tested whether neighborhood cohesion operated as a protective factor. Data came from 461 African American adolescents (mean age = 15.24 years, SD = 1.56; 50 % female) participating in the Project on Human Development in Chicago Neighborhoods. Multilevel models revealed that perceived discrimination within youth’s neighborhoods was positively related to externalizing, and discrimination both within and outside of youth’s neighborhoods predicted greater internalizing problems. Neighborhood cohesion moderated the association between within-neighborhood discrimination and externalizing. Specifically, high neighborhood cohesion attenuated the association between within-neighborhood discrimination and externalizing. The discussion centers on the implications of proximal stressors and neighborhood cohesion for African American adolescents’ adjustment.  相似文献   
950.
One of the most consistent findings in developmental criminology is the “age–crime curve”—the observation that criminal behavior increases in adolescence and decreases in adulthood. Recently, Brown and Males (Justice Policy J 8:1–30, 2011) conducted an analysis of aggregate arrest, poverty, and population data from California and concluded that the widely-observed adolescent peak in rates of offending is not a consequence of developmental factors, but rather an artifact of age differences in economic status. Youngsters, they argue, offend more than adults because they are poorer than adults. The present study challenges Brown and Males’ proposition by analyzing data from the National Longitudinal Study of Youth (NLSY97; N = 8,984; 51 % female; 26 % Black, 21 % Hispanic, 52 % non-Black, non-Hispanic; ages 12–18 at Wave 1), which collected measures of criminal behavior and economic status at multiple time points. Consistent with scores of other studies, we find that criminal offending peaks in adolescence, even after controlling for variation in economic status. Our findings both counter Brown and Males’ claim that the age–crime curve is illusory and underscore the danger of drawing inferences about individual behavior from analysis of aggregated data.  相似文献   
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