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   413篇
  免费   71篇
  国内免费   31篇
  2023年   2篇
  2022年   4篇
  2021年   8篇
  2020年   9篇
  2019年   7篇
  2018年   8篇
  2017年   12篇
  2016年   13篇
  2015年   9篇
  2014年   16篇
  2013年   56篇
  2012年   13篇
  2011年   17篇
  2010年   13篇
  2009年   24篇
  2008年   26篇
  2007年   26篇
  2006年   18篇
  2005年   21篇
  2004年   22篇
  2003年   17篇
  2002年   16篇
  2001年   16篇
  2000年   21篇
  1999年   10篇
  1998年   9篇
  1997年   9篇
  1996年   8篇
  1995年   13篇
  1994年   9篇
  1993年   5篇
  1992年   12篇
  1991年   7篇
  1990年   1篇
  1989年   3篇
  1988年   4篇
  1987年   2篇
  1986年   2篇
  1985年   5篇
  1984年   3篇
  1983年   2篇
  1982年   2篇
  1981年   3篇
  1980年   3篇
  1979年   1篇
  1977年   3篇
  1976年   4篇
  1975年   1篇
排序方式: 共有515条查询结果,搜索用时 93 毫秒
111.
The ethical issues in conducting research on preventing HIV infection are among the most complex of any area of human subjects research. This article is an update of a 1987 article that addressed potential conflicts between research design and ethics with respect to AIDS prevention among injecting drug users. The present article reviews current ethical issues that arise in the design and conduct of HIV/AIDS prevention research focused on injecting drug users. Disclaimer: The content of this publication is solely the responsibility of the authors and does not necessarily represent the views of the Beth Israel Medical Center or Johns Hopkins University.  相似文献   
112.
This study examined the patterns of drug use and criminal activities among Latino arrestees. The findings indicate that while the prevalence of drug use at time of arrest, and in the prior 12 months were significantly lower for Latinos compared to Whites and Blacks, drug use still is of concern for this ethnic group. Almost 50% of Latinos reported drug use in the last year, and more importantly, they were more likely to report using dangerous drugs such as cocaine, heroin, and PCP than any other ethnic group. These findings are even more alarming considering that, for the most part, Latino drug users were treatment-naive, and that less than half perceived a need for drug treatment. Regarding criminal activities, Latinos were less likely to have a history of prior arrests and to have been arrested in the year prior to the interview than any other ethnic group. Interestingly, those immigrants who have resided in the U.S. for less than 1 year were significantly more likely to have been charged with drug-related crimes. U.S. born Latinos were more likely to have been arrested for property crimes, while Central American immigrants were more likely than any other Latino group to have been arrested for violent and domestic violence crimes. Treatment and policy implications of these findings are discussed.  相似文献   
113.
The effect of ethanol on the cigarette smoking of alcoholic subjects was studied in a residential laboratory. During daily 6-hr sessions, cigarettes were obtained either by request to the ward staff or by operation of a lever (fixed-ratio 5 or 10). In a mixed sequence across days, sessions involved ingestion of either vehicle (orange juice or vehicle plus ethanol (133.7 g). During ethanol sessions, the rate of cigarette smoking increased from 26% to 117% of vehicle levels. A series of control studies eliminated a number of potential behavorial mechanisms for the observed effect and indicated that the ethanol-induced increase in cigarette smoking occurred under a variety of experimental conditions: (1) when smoking could not occur concurrently with ethanol or vehicle consumption; (2) when subjects were not allowed to socialize; (3) when ingestion of ethanol or vehicle was scheduled for a number of consecutive days; (4) when various doses of ethanol were administered under blind conditions. In control experiments, weighing unsmoked tobacco and counting the number of puffs per cigarette indicated the effect was not due to smoking less of each cigarette. The effect was not limited to the experimental sessions alone, since total daily smoking was higher on ethanol days than vehicle days.  相似文献   
114.
115.
Pigeons were trained to track different key colors, depending on whether they had been injected with phencyclidine or saline prior to the session. A second-order schedule was used to generate large numbers of responses prior to the initial food delivery. The procedure offers several advantages over traditional procedures for studying drug discrimination.  相似文献   
116.
In this paper, modern statistics is considered as a branch of psychometrics and the question of how the central problems of statistics can be resolved using psychometric methods is investigated. Theories and methods developed in the fields of test theory, scaling, and factor analysis are related to the principle problems of modern statistical theory and method. Topics surveyed include assessment of probabilities, assessment of utilities, assessment of exchangeability, preposterior analysis, adversary analysis, multiple comparisons, the selection of predictor variables, and full-rank ANOVA. Reference is made to some literature from the field of cognitive psychology to indicate some of the difficulties encountered in probability and utility assessment. Some methods for resolving these difficulties using the Computer-Assisted Data Analysis (CADA) Monitor are described, as is some recent experimental work on utility assessment.1980 Psychometric Society presidential address.I am indebted to Paul Slovic and David Libby for valuable consultation on the issues discussed in this paper and to Nancy Turner and Laura Novick for assistance in preparation.Research reported herein was supported under contract number N00014-77-C-0428 from the Office of Naval Research to The University of Iowa, Melvin R. Novick, principal investigator. Opinions expressed herein reflect those of the author and not those of sponsoring agencies.  相似文献   
117.
A simple model for the utility of gambling   总被引:2,自引:0,他引:2  
A model of the utility of gambling is presented in a modified von Neumann-Morgenstern format. Axioms imply a utility function that preserves preferences between sure things and between gambles. The addition of a utility of gambling term to the expected utility of a gamble preserves preference comparisons between gambles and sure things. Aspects of the utility of gambling are noted, and comparisons are made to standard concepts of risk attitudes.The author is indebted to Joseph Sani for valuable discussions on the topic of this paper.  相似文献   
118.
The present research was concerned with identifying and validating the problematic interpersonal situations of male veteran drug addicts. In Study I, 20 addicts self-monitored the situations with which they had difficulty coping and their associated characteristics throughout a 2-week period. Fifty situations were obtained and then rewritten into specific interpersonal scenarios. In Study II, a second group of 36 addicts and a comparison group of 20 disabled veterans rated the commonality and difficulty of each scenario along seven-point scales. Univariate ANOVAs found that five scenarios received ratings greater than four on both scales and were associated with significantly higher ratings by the addicts. These preliminary scenarios may serve as role-play situations during social-skills assessment and training and may provide further information regarding the interpersonal determinants of relapse occasioned in the natural environment. The need for controlled comparison studies using behavioral measures and an overall improvement in the methodological rigor of research in the area is discussed.The authors acknowledge the editorial comments of Ted D. Nirenberg, Ph.D., on an earlier draft of this paper. Portions of these data were presented at the Fifth World Congress on Behavior Therapy, Washington, DC.  相似文献   
119.
A positive reinforcement contingency increased opioid abstinence during outpatient dose tapering (4, 2, then 0 mg/day during Weeks 1 through 3) in non‐treatment‐seeking heroin‐dependent volunteers who had been maintained on buprenorphine (8 mg/day) during an inpatient research protocol. The control group (n = 12) received $4.00 for completing assessments at each thrice‐weekly visit during dose tapering; 10 of 12 lapsed to heroin use 1 day after discharge. The abstinence reinforcement group (n = 10) received $30.00 for each consecutive opioid‐free urine sample; this significantly delayed heroin lapse (median, 15 days).  相似文献   
120.
通过对本地一所三级甲等医院进行的围手术期抗菌药物的干预对照研究,用SPSS软件对470个手术病例的调查资料进行了统计分析,加强抗菌药物的用药管理及进行用药干预,能在对住院时间和手术切口感染率无影响的同时,明显降低手术病例的药品费用,特别是抗茵药品的费用,减轻患者负担。  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