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   19654篇
  免费   591篇
各国政治   673篇
工人农民   816篇
世界政治   1264篇
外交国际关系   588篇
法律   12435篇
中国共产党   34篇
中国政治   185篇
政治理论   4031篇
综合类   219篇
  2020年   238篇
  2019年   273篇
  2018年   372篇
  2017年   452篇
  2016年   464篇
  2015年   379篇
  2014年   388篇
  2013年   1718篇
  2012年   437篇
  2011年   511篇
  2010年   407篇
  2009年   519篇
  2008年   564篇
  2007年   593篇
  2006年   565篇
  2005年   520篇
  2004年   504篇
  2003年   455篇
  2002年   451篇
  2001年   714篇
  2000年   644篇
  1999年   515篇
  1998年   298篇
  1997年   224篇
  1996年   259篇
  1995年   237篇
  1994年   248篇
  1993年   249篇
  1992年   398篇
  1991年   462篇
  1990年   416篇
  1989年   410篇
  1988年   418篇
  1987年   391篇
  1986年   448篇
  1985年   422篇
  1984年   373篇
  1983年   346篇
  1982年   245篇
  1981年   227篇
  1980年   204篇
  1979年   242篇
  1978年   171篇
  1977年   176篇
  1976年   151篇
  1975年   132篇
  1974年   146篇
  1973年   154篇
  1972年   118篇
  1971年   118篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Emotional and behavioral correlates of Type A behavior in children and adolescents were examined in 184 fifth-, seventh-, and ninth-grade students, classified as high or low Type A, using self-report, teacher ratings (fifth grade only), and structured interview procedures. Measures included the Hunter-Wolf A-B Rating Scale, Behavioral Symptoms of Stress Inventory, Dimensions of Temperament Survey, Desire for Control Scale, Eysenck Personality Inventory, and the Multiple Affect Adjective Checklist. High Type A children reported significantly more stressed-related behaviors, higher levels of depression, anger, anxiety, and cognitive disorganization, and greater reactivity than Low Type A. No differences were found on measures of temperament (activity level, attention span, adaptibility, and rhythmicity), desire for control, or introversion-extroversion. Females, in general, reported significantly more behavioral stress symptoms. However, no other gender differences were found. Possible reasons for reported differences between Type A children and adults are discussed, along with gender differences in behavioral symptoms. Need for multiple measures of Type A across situation is considered along with need for controlled longitudinal studies of Type A components and the influence of contexts.Received Ph.D. from Stanford. Research interests: Adolescent problems, stress.Received Ph.D. from Stanford. Research interests: Type A, anger/hostility; AIDS prevention.Received Ph.D. from Stanford. Research interests: child & family problems, stress disorders.Received Ph.D. from Stanford. Research interests: psychoneuroimmunology.Received Ph.D. from Stanford. Research interests: pain disorders, stress.Received Ph.D. from Stanford.Received Ph.D. from Stanford. Research interests: anxiety and phobic disorders.  相似文献   
982.
Eighty college males were given an expanded identity status interview which included two new interpersonal-sexual areas, “attitudes towards sexual expression” and “sex-role beliefs.” The relative contribution of the new content areas as well as of the standard three areas (occupation, religion, and politics) to overall identity status was assessed by noting the extent of correspondence. Identity status in each content area was also compared with performance on the dependent variable of cognitive complexity. Ideology contributed more than occupation both to overall status rating, as well as to discrimination on the dependent variable. Results on the two new areas supported the view that interpersonal-sexual concerns are important for men's identity development as well as for women's. The finding that all interview areas corresponded well with overall identity status and discriminated significantly on the dependent measure leads to the suggestion that the process variables of crisis and commitment may so overshadow a particular content area that any content of personal relevance for the late adolescent might be used in investigating ego identity development.  相似文献   
983.
A path-analytic study was undertaken to investigate the proposed relationship between physical attractiveness, need for intimacy, self-disclosure, thought about one's dating partner, and reported romantic love. Extrapolations from theories by Murstein (1971) and I. Reiss (1960), and conclusions from other empirical work, provided the background for the assessment of the relationship between the four proposed predictive factors and the development of romantic affect. During the winter of 1977-78 656 college students responded to a survey assessing each of the four predictors and romantic love. Path structures were initially estimated for male and female subsamples. Since few significant sex differences were noted, coefficients were compared for groups of students involved in dating relationships of varying durations. All four predictors were significantly associated with the subjects' self-reported romantic affect toward their dating partner. In all analyses, thinking about one's partner was found to be the most potent predictor. The data suggest the earlier work by Murstein and Reiss offer both testable and productive theoretical foundations for the study of romantic involvement. However, in future work it would be beneficial to (a) search for more numerous and powerful antecedents to romantic love; (b) delineate the specific role of cognitive processes in influencing romantic attachment; (c) compare relationships on criteria other than months of involvement; and (d) seek to examine love from the perspectives of both individuals involved in the dyadic relationship.Received her Ph.D. from the Pennsylvania State UniversityReceived his Ph.D. from The Pennsylvania State University.  相似文献   
984.
To investigate the incidence and correlates of bulimic behavior, 1268 high school females were surveyed. A 47-item questionnaire was used to identify a group of students that would meet the DSM-III criteria for a probable diagnosis of bulimia. Students were then compared across the four content areas of demographics; body perception and weight information; dieting, exercise and menstrual behavior; and frequency of bingeing and purging behavior. Results indicated that 4.9% of the students met rigorous criteria for the diagnosis of bulimia. Between-group comparisons indicated that body dissatisfaction, drive for thinness, and chronicity of dieting differentiated the two groups.This work was supported by Biomedical Research Grant #RR5476, the Sears Allstate Foundation, and the George and Tina Barr Foundation.Main interest is eating disorders.  相似文献   
985.
Although the Federal Health Privacy Rule has evened out some of the inconsistencies between states' health privacy laws, gaps in protection still remain. Furthermore, the Federal Rule contains some lax standards for the disclosure of health information. State laws can play a vital role in filling these gaps and strengthening the protections afforded health information. By enacting legislation that has higher privacy-protective standards than the Federal Health Privacy Rule, states can play three important roles. First, because they can directly regulate entities that are beyond HHS's mandate, states can afford their citizens a broader degree of privacy protection than the Federal Health Privacy Rule. Second, by having state health privacy laws, states can enforce privacy protections at the local level. Finally, action by the states can positively influence health privacy policies at the federal level by raising the standard as to what constitutes sufficient privacy protection. High privacy protections imposed by states may serve as the standard for comprehensive federal legislation, if and when Congress reconsiders the issue. So far, states' reactions to the Federal Privacy Rule have been mixed. Only time will tell whether states will assume the mantle of leadership on health privacy or relinquish their role as the primary protectors of health information.  相似文献   
986.

Introduction

Herbert Alexander Simon  相似文献   
987.
988.
Validation of a 16-locus fluorescent multiplex system   总被引:24,自引:0,他引:24  
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results.  相似文献   
989.
Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method.  相似文献   
990.
Premenstrual Syndrome (PMS) is believed to affect up to 90% of women of reproductive age. A small subset of women have been identified who actually experience psychotic symptoms in the premenstrual phase of their cycles. Not surprisingly, PMS has made it into the courts where it has been offered as a defense for criminal acts. The defense has generally fared poorly in the United States, although it has been successfully used as a factor in supporting diminished capacity in Great Britain. The following paper sets out to review the medical literature on premenstrual syndrome with a particular focus on premenstrual psychosis. Available literature from both medical and legal sources is then utilized to investigate instances in which premenstrual psychosis has been invoked as a defense in the courts.  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