首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   597篇
  免费   24篇
各国政治   42篇
工人农民   69篇
世界政治   28篇
外交国际关系   36篇
法律   307篇
中国政治   10篇
政治理论   127篇
综合类   2篇
  2023年   5篇
  2022年   5篇
  2021年   7篇
  2020年   12篇
  2019年   32篇
  2018年   33篇
  2017年   19篇
  2016年   28篇
  2015年   17篇
  2014年   23篇
  2013年   110篇
  2012年   27篇
  2011年   27篇
  2010年   16篇
  2009年   17篇
  2008年   20篇
  2007年   24篇
  2006年   27篇
  2005年   22篇
  2004年   19篇
  2003年   13篇
  2002年   14篇
  2001年   9篇
  2000年   4篇
  1999年   2篇
  1998年   6篇
  1997年   5篇
  1996年   7篇
  1995年   7篇
  1993年   5篇
  1992年   2篇
  1991年   4篇
  1989年   5篇
  1988年   4篇
  1987年   3篇
  1986年   7篇
  1984年   4篇
  1983年   2篇
  1982年   3篇
  1977年   2篇
  1976年   4篇
  1975年   1篇
  1974年   3篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
  1969年   1篇
  1968年   4篇
  1967年   1篇
排序方式: 共有621条查询结果,搜索用时 15 毫秒
571.
Purpose. Three studies examined the degree to which investigative interviewers' adherence to best‐practice guidelines is consistent across similar mock interviews. Method. In each study, two interviews were administered within a period of several hours. Further, group and individual stability of interviewer performance was analysed, and performance was measured by calculating the proportion of open‐ended and leading questions as well as the presence of predetermined problem behaviours. The studies varied depending on the type of interview paradigm employed. Interviewer performance in Study 1was measured in a group context where participants rotated between the role of interviewer, child respondent, and observer. In Study 2, an adult played the role of a child recalling abuse but this occurred in isolation (participants did not observe others or play the child). Study 3 was similar to Study 2 except that in each interview an unfamiliar child aged 5–7 years recalled an innocuous event. Results. Interviewer performance was relatively stable across tasks, although the strength of the relationship between measures varied across analyses. Improvement in open‐ended question usage occurred in Study 1 but not Studies 2 and 3. Irrespective of the assessment context, the dichotomous rating scale yielded greater consistency than when questions were tallied. Further, group stability overestimated individual stability. The practical implications of these findings for trainers and researchers are discussed.  相似文献   
572.
Abstract: Samples containing the toxic castor bean protein ricin have been recently seized in connection with biocriminal activity. Analytical methods that enable investigators to determine how the samples were prepared and to match seized samples to potential source materials are needed. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here, we describe the use of solid‐phase microextraction and headspace analysis to determine whether castor beans were processed by acetone extraction. We prepared acetone‐extracted castor bean mash, along with controls of unextracted mash and mash extracted with nonacetone organic solvents. Samples of acetone‐extracted mash and unextracted mash were stored in closed containers for up to 109 days at both room temperature and ?20°C, and in open containers at room temperature for up to 94 days. Acetone‐extracted bean mash could consistently be statistically distinguished from controls, even after storage in open containers for 94 days.  相似文献   
573.
Abstract: The Food and Drug Administration does not require surgical sutures to be tracked by manufacturer, physician, or patient; thereby, surgical sutures have been of little use to forensic practitioners who are tasked with establishing a positive identification with biological evidence. This study demonstrates the investigative process used to pinpoint suture manufacturers by presenting a case where surgical sutures were a distinctive characteristic that aided in the positive identification of skeletal remains. The suture’s manufacturer, construction material and structure, size, and medical use was determined by contacting a local surgical suture and orthopedic implant manufacturer and utilizing publicly available manufacturer websites, which provide catalogs and specific product details. This research was one of many lines of evidence used to establish the positive identification of a 47‐year‐old male.  相似文献   
574.

Abstract:

An alarming number of drownings occur in lifeguarded swimming areas, where one might presume swimmers are protected from injury. One reason drownings occur in lifeguarded swimming areas is because lifeguard surveillance is a highly difficult task. Observational research suggests lifeguards are usually alert, but researchers also report egregious examples of inattention. We offer three strategies that have initial empirical support to reduce risk of drowning at lifeguarded swimming areas: (a) regular training to help lifeguards recognize they are vulnerable to drowning events and to raise their confidence; (b) regular practice via simulated emergency responses, and (c) addressing staff schedules so lifeguards can devote full attention to protecting swimmer safety while on duty. ‎  相似文献   
575.
576.
Polydimethylsiloxane (PDMS) is commonly used to lubricate condoms. The detection of PDMS on swabs from complainants can be used to support an allegation of sexual assault. Previous research has focused on establishing analytical techniques for detecting PDMS. This research examined the persistence of PDMS on the penis, in the vagina, in the mouth, and on skin. The longest PDMS detection times were 20 h on the penis, 35 h in the vagina, and 52 h on skin. PDMS was detected up to 4 h in the mouth if the participant did not eat or drink and up to 9 h if the participant slept. PDMS was not detected in the mouth after eating or drinking. The presence of biological fluids had no detrimental effect on the analysis. Aqueous extraction of swabs for DNA did not remove any significant amount of PDMS; hence, swab remains could be subsequently analyzed for PDMS.  相似文献   
577.
State and local governments are designing programs to prevent child maltreatment at an increasing rate. A relatively small portion of families offered these programs go on to engage in and complete services. Workers in a child maltreatment prevention program implemented across 21 sites in 1 state documented outreach efforts in logs maintained by program evaluators. Additionally, evaluators interviewed 23 outreach workers and supervisors who were developing and refining outreach strategies in this prevention program. Data from logs and responses to interviews speak to challenges in navigating prevention outreach with families to achieve engagement and buy-in, particularly when “cold-calling” about screened-out reports of child maltreatment. This paper presents a summary of barriers and facilitators of family engagement in outreach for prevention services, guidance from the public health literature on improving outreach strategies for at-risk populations, and suggested practice, policy, and research implications.  相似文献   
578.
Although researchers have made numerous advances in the understanding of the nature, extent, and dynamics of violence against women (VAW), there is an ever-increasing need for data used in academic research and within policy decision-making to be collected via rigorous methodological designs to accurately measure the incidence and impact of VAW. What is now needed are research collaborations within an interdisciplinary research cluster that will expand understanding of the complex nature of VAW. The current article details an agenda or “call to action” to address deficiencies and advance VAW research, in addition to informing VAW intervention and prevention efforts.  相似文献   
579.
Perceptions of children's credibility were studied in two experiments wherein participants watched a videotape of a 4- to 5- or a 6- to 7-year old child report details of a play session that had been experienced once (single-event) or was the last in a series of four similar play sessions (repeat-event). The child's report was classified as high or low accurate. In Experiments 1 and 2, reports of repeat-event children were judged to be less believable on several measures. In Experiment 1, younger children were viewed as less credible than older children. In both experiments, neither undergraduates nor community members correctly discriminated between high- and low-accurate reports. Content analysis in Study 3 revealed the relationship between age and event frequency and children's credibility ratings was mediated by the internal consistency of children's reports. Recent research on children's reports of instances of repeated events has identified several challenges facing children who report repeated abuse. These data bring to light another potential difficulty for these children.  相似文献   
580.
On 13 December 2000, British Telecom (BT) filed what must be one of the more unlikely patent infringement actions to have come before the courts recently. As a result of a routine review of its global patent portfolio, BT made the somewhat serendipitous discovery that it owns an old US patent which, according to BT, covers the concept of hyperlinking. The patent was granted in 1989 and is due to run until 2006. Similar patents were filed around the world, but have all now expired. This article explores the passage of the dispute in the US courts and explains how BT’s case came to flounder at the first hurdle.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号