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   11002篇
  免费   108篇
各国政治   398篇
工人农民   378篇
世界政治   725篇
外交国际关系   359篇
法律   6780篇
中国政治   67篇
政治理论   2315篇
综合类   88篇
  2020年   113篇
  2019年   167篇
  2018年   191篇
  2017年   219篇
  2016年   218篇
  2015年   170篇
  2014年   189篇
  2013年   949篇
  2012年   223篇
  2011年   272篇
  2010年   212篇
  2009年   271篇
  2008年   278篇
  2007年   278篇
  2006年   269篇
  2005年   245篇
  2004年   240篇
  2003年   250篇
  2002年   238篇
  2001年   426篇
  2000年   372篇
  1999年   301篇
  1998年   165篇
  1997年   123篇
  1996年   137篇
  1995年   133篇
  1994年   134篇
  1993年   141篇
  1992年   234篇
  1991年   253篇
  1990年   242篇
  1989年   252篇
  1988年   226篇
  1987年   228篇
  1986年   263篇
  1985年   260篇
  1984年   232篇
  1983年   217篇
  1982年   152篇
  1981年   128篇
  1980年   115篇
  1979年   153篇
  1978年   88篇
  1977年   114篇
  1976年   98篇
  1975年   77篇
  1974年   95篇
  1973年   86篇
  1972年   79篇
  1971年   72篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
851.
852.
A survey was made of American Academy of Forensic Sciences (AAFS) forensic psychiatrists to evaluate whether there is concern among them about potential ethical problems in criminal justice work. Of the respondents, 93.8% had encountered such problems. The main concerns indicated were about those psychiatrists who become a "hired gun," become an advocate, do not give an honest opinion, or have problems with confidentiality. The need for ethical guidelines and further debate about ethical issues is presented.  相似文献   
853.
Demographic and trend analysis of 881 consecutive suicides in blacks and whites is presented. For the years 1975 through 1984, the suicide rate was 15.1/100 000 and did not significantly change. White males were overrepresented in all age groups, had an overall suicide rate of 34.9, and showed a small but statistically significant increase in rate which was not accounted for by any specific age group. White females, in general, were represented in proportion to their prevalence in the population, and those ages 20 to 24 demonstrated an increasing suicide rate which was small. Black males were at highest risk in their twenties, showed no significant trends, and were also represented near their prevalence in the population. Black females of all ages were underrepresented, and had low suicide rates which decreased with time. No significant rate changes were noted for teenagers or the elderly. Firearms was the method of choice in all groups, although methods varied with age, race, and sex, and male children preferred hanging. Small but significant increases were noted for the prevalence of nondrug methods in females and carbon monoxide deaths in white males. Similarities and differences to larger scale studies are discussed. Suicide may have characteristics unique to given geographical areas and pervasive to all areas. The authors advocate study and publication of local data to clarify further the nature of suicide.  相似文献   
854.
A method is described for the gas chromatographic quantitation of carbon monoxide by means of thermal conductivity detection. Carbon monoxide is released from blood samples as small as 0.02 mL using a unique extraction chamber. The method was compared to a standard gas chromatographic and spectrophotometric method of carbon monoxide quantitation. It was comparable to the former with all samples evaluated and apparently more reliable than the latter with decomposed samples.  相似文献   
855.
Purpose: in the literature, the term ‘Internet crime’ has been coined to indicate the scenario in which a victim of homicide or other crimes is met through a chat room, and lured to death at the hands of the murderer. Various criticisms have been made of this new concept, on the grounds that the outcome is no different from that of other crimes committed without the use of Web resources, and so the method used has no particular influence. Indeed, it has been claimed that informatic crime just reflects a technological change in the nature of crime rather than a new form of criminal behavior attributable to the use of the Internet for criminal purposes. Method: our reflections were prompted by our experience as expert forensic psychiatry witnesses in three cases in which the aggressors had confessed to having had an exclusively virtual relationship with the victims, in which they spent a lot of time daily in a chat room. Conclusion: this scenario offers points for reflection on the nature of Web-mediated victim–aggressor interactions, to assess the effects on the planning and commission of the crime. Discussion. it’s our opinion that there really is such a thing as Internet-correlated crime, because in this case the quality and quantity of the Internet interactions progressively altered the men’s perception of the real relationship between themself and their victims.  相似文献   
856.
857.
By potential damage, chemical terroristic attacks are much more dangerous than terroristic bombing. To fight chemical terrorism it is necessary to create the system of medical-environmental defense of the population. In line with emergency medicine, forensic medical service is a very important element of the antiterroristic defense. The activity of forensic-medical experts in the field of terroristic chemical attack is analysed.  相似文献   
858.
Thirty years have passed since the publication of "Cross-Subsidization:Pricing in Public Enterprises." The article rigorously definedcross-subsidization and is now a standard citation of regulatorsand scholars addressing the pricing of regulated multiproductfirms. The incremental cost test and the stand-alone cost test,however, have often been misunderstood and misapplied. Thisarticle answers the most common questions that have arisen inthe application of these tests for cross-subsidization and correctsthe most common errors that have been committed in their application.  相似文献   
859.
A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53-73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI/Pvu II, and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 +/- 7.2%. An example for the application of MZ 1.3 to paternity testing in an incest case is given. The probe can be used with radioactive or non-radioactive detection systems. An approach is presented to compare polymorphic fragment patterns from individuals obtained by independent gel runs on the basis of relative band positions (RBP) and calculated in a computerized analysis.  相似文献   
860.
Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.  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