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   18461篇
  免费   364篇
各国政治   907篇
工人农民   1402篇
世界政治   1032篇
外交国际关系   805篇
法律   10324篇
中国共产党   3篇
中国政治   156篇
政治理论   4086篇
综合类   110篇
  2023年   59篇
  2020年   167篇
  2019年   202篇
  2018年   1473篇
  2017年   1454篇
  2016年   1261篇
  2015年   307篇
  2014年   287篇
  2013年   1355篇
  2012年   468篇
  2011年   1256篇
  2010年   1238篇
  2009年   858篇
  2008年   1019篇
  2007年   927篇
  2006年   277篇
  2005年   302篇
  2004年   431篇
  2003年   419篇
  2002年   232篇
  2001年   386篇
  2000年   361篇
  1999年   309篇
  1998年   173篇
  1997年   130篇
  1996年   140篇
  1995年   152篇
  1994年   134篇
  1993年   119篇
  1992年   170篇
  1991年   167篇
  1990年   158篇
  1989年   147篇
  1988年   167篇
  1987年   163篇
  1986年   171篇
  1985年   154篇
  1984年   160篇
  1983年   165篇
  1982年   103篇
  1981年   71篇
  1980年   83篇
  1979年   107篇
  1978年   86篇
  1977年   77篇
  1976年   70篇
  1975年   58篇
  1972年   53篇
  1971年   54篇
  1969年   56篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
The distribution of plasminogen phenotypes in the population of Veneto was investigated by ultrathin-layer isoelectric focusing. In our sample (n = 1325), the three common phenotypes PLG1, PLG2, PLG2-1 and two further phenotypes PLG1-V and PLG2-V were, observed and the following frequencies calculated: PLG1 = 0.84038; PLG2 = 0.15811; PLGV = 0.00151. These gene frequencies are compared to those found in other populations. Analysis of 41 mother-child pairs was in agreement with an autosomal codominant inheritance.  相似文献   
902.
Cytochrome b gene for species identification of the conservation animals   总被引:7,自引:0,他引:7  
A partial DNA sequence of cytochrome b gene was used to identify the remains of endangered animals and species endemic to Taiwan. The conservation of animals species included in this study were: the formosan gem-faced civets, leopard cats, tigers, clouded leopards, lion, formosan muntjacs, formosan sika deers, formosan sambars, formosan serows, water buffalo, formosan pangolins and formosan macaques. The control species used included domestic cats, domestic dogs, domestic sheeps, domestic cattles, domestic pigs and humans. Heteroplasmy was detected in the formosan macaque, domestic pig and domestic cats. The frequencies of heteroplasmy in these animals were about 0.25% (1 in 402bp). Sequences were aligned by Pileup program of GCG computer package, and the phylogenetic tree was constructed by the neighbor-joining method. The results of sequence comparison showed that the percentage range of sequence diversity in the same species was from 0.25 to 2.74%, and that between the different species was from 5.97 to 34.83%. The results of phylogenetic analysis showed that the genetic distance between the different species was from 6.33 to 40.59. Animals of the same species, both the endangered animal species and domestic animals, were clustered together in the neighbor-joining tree. Three unknown samples of animal remains were identified by this system. The partial sequence of cytochrome b gene adopted in this study proved to be usable for animal identification.  相似文献   
903.
Christine Battersby has argued that it is Kant (and not Descartes) who provides the paradigm model of what it is to be a self in modernity. The Kantian self is established in opposition to its other. The body is commonly envisaged as a container, with selfhood as something that is defended against the outside. In contrast, she proposes a feminist reworking of such a model of selfhood, applicable to both men and women, in which the self and other emerge over time through patterns of relationality. This paper introduces Battersby’s work by focusing upon her early analysis of Kantian aesthetics, in particular the sublime. The aim is to draw out some of the legal and political implications of her work, particularly with regard to the common law’s developing conception of privacy. This is carried out by distinguishing her ontological position from the psychology of Carol Gilligan and then by considering the overlapping concerns of Jennifer Nedelsky in the area of legal theory.
Janice RichardsonEmail:
  相似文献   
904.
Although adolescents are commonly assumed to be rebellious, risky and moody, two experiments demonstrate for the first time that these beliefs operate both explicitly and implicitly as stereotypes. In Experiment 1, participants (a) explicitly endorsed adolescent stereotypes and (b) implicitly associated adolescent stereotyped words more rapidly with the adolescent than the adult social category. Individual differences in the explicit endorsement of adolescent stereotypes predicted explicit perceptions of the rebelliousness of a 17-year-old but not a 71-year-old, although individual differences in implicit stereotyping did not. Identification with adults was associated with greater implicit stereotyping but not explicit stereotyping. In Experiment 2, subliminal exposure to adolescent stereotyped words increased subsequent perceptions of the rebelliousness of a 17-year-old but not a 71-year-old. Although individual differences in implicit adolescent stereotyping did not predict explicit evaluations of adolescents, stereotypes of adolescents nevertheless influenced explicit evaluations unconsciously and unintentionally.
Curtis D. HardinEmail:
  相似文献   
905.
We examine the understudied link between mental/physical health problems and their relationship with perceived unsafety via higher levels of vulnerability. We examine this relationship by linking data at the individual-level, the neighborhood-level, and the county-level using the Portraits of American Life Survey (PALS). Using this data we examine the effect of individual and neighborhood conditions on perceived safety while controlling for county-level crime rates. Findings indicate that higher numbers of physical impairment and mental health issues are independently related to higher levels of perceived unsafety. Both mental and physical health problems are associated with higher levels of fear. These higher levels of vulnerability then directly contribute to higher levels of feeling of unsafety. Unlike past research, we find a mental health link to fear of crime that cannot be explained by physical impairments.  相似文献   
906.
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings.  相似文献   
907.
Charles Peirce’s semeiotic is inseparable from his account of the three categories of experience and his metaphysics. The discussion summarizes his account of the categories and considers the way they have ontological implications. These implications are then focused on Peirce’s Apapism, which is his way of referring to a theory of evolution. Finally, some suggestions are offered for a way the semeiotic with the metaphysical implications, especially their relevance for a theory of evolution, propose how Peirce might apply them for questions of jurisprudence.
Carl R. HausmanEmail:
  相似文献   
908.
The optimized summed scored attributes (OSSA) method was recently introduced and validated for nonmetric ancestry estimation between American Black and White individuals. The method proceeds by scoring, dichotomizing, and subsequently summing ordinal morphoscopic trait scores to maximize between‐group differences. This study tests the applicability of the OSSA method for sex estimation using five cranial traits given the methodological similarities between classifying sex and ancestry. A large sample of documented crania from Japan and Thailand (n = 744 males, 320 females) are used to develop a heuristically selected OSSA sectioning point of ≤1 separating males and females. This sectioning point is validated using a holdout sample of Japanese, Thai, and Filipino (n = 178 males, 82 females) individuals. The results indicate a general correct classification rate of 82% using all five traits, and 81% when excluding the mental eminence. Designating an OSSA score of 2 as indeterminate is recommended.  相似文献   
909.
Many Americans own guns to protect themselves against other people, but there is evidence that both victimization and gun access increase suicide risk. We conducted qualitative interviews with informants of 17 suicide cases in New Orleans of the 60 who died between January 2015 and April 2016 to understand the relationship between past trauma, gun access and storage, and suicide. Nine cases had experienced a past trauma, including three who had recently had a family member killed by homicide. Eight died via firearm; of those, seven owned the guns they used to take their lives and stored them locked (but loaded) at home or in their cars. Preventing community violence and addressing its sequelae may be important for reducing suicides. A multi‐pronged strategy consisting of policies, education, and marketing will likely be needed to address the risk of suicide conferred by gun access.  相似文献   
910.
An often implicit assumption of perceptual deterrence tests is that the elicited values pertaining to arrest risk reflect stable underlying beliefs. But researchers in other disciplines have found that reported expectations are highly susceptible to exogenous factors (e.g., anchors and question ordering), indicating that such values are somewhat arbitrary responses to probabilistic questions. At the same time, reported expectations are coherent within persons, such that respondents rank order them rationally. For deterrence, then, absolute values reported on arrest risks are likely not stable but individuals still rank order specific crimes in meaningful ways. We examine the interpretability of reported arrest risk for three possibilities: 1) Reported risks are stable probabilistic values; 2) reported risks are arbitrary and uninformative for deterrence research; or 3) reported risks display “coherent arbitrariness” with unstable values between individuals but stable rank ordering of crimes within individuals. Through the use of three random experiments of college students, our results indicate that elicited risk perceptions are arbitrary in that they are influenced by the presentation of anchors and question ordering. Nevertheless, the rank ordering of crimes within and across conditions is unaffected by the presentation of anchors, suggesting that reported risks are locally coherent within persons.  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