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   13483篇
  免费   350篇
各国政治   714篇
工人农民   404篇
世界政治   950篇
外交国际关系   514篇
法律   8193篇
中国共产党   1篇
中国政治   54篇
政治理论   2845篇
综合类   158篇
  2020年   133篇
  2019年   177篇
  2018年   261篇
  2017年   265篇
  2016年   283篇
  2015年   208篇
  2014年   229篇
  2013年   1466篇
  2012年   333篇
  2011年   345篇
  2010年   294篇
  2009年   306篇
  2008年   340篇
  2007年   323篇
  2006年   346篇
  2005年   291篇
  2004年   285篇
  2003年   304篇
  2002年   305篇
  2001年   490篇
  2000年   432篇
  1999年   361篇
  1998年   176篇
  1997年   188篇
  1996年   144篇
  1995年   151篇
  1994年   161篇
  1993年   152篇
  1992年   260篇
  1991年   305篇
  1990年   271篇
  1989年   294篇
  1988年   259篇
  1987年   277篇
  1986年   281篇
  1985年   257篇
  1984年   243篇
  1983年   252篇
  1982年   170篇
  1981年   166篇
  1980年   139篇
  1979年   199篇
  1978年   137篇
  1977年   114篇
  1976年   117篇
  1975年   120篇
  1974年   142篇
  1973年   134篇
  1972年   118篇
  1971年   103篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
951.
952.
No reliable data are available on cases of lethal child abuse (by active force) in the area of Federal Republic of Germany prior to reunification (the former West Germany). In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in nearly the entire area of Federal Republic of Germany. RESULTS: The study center received information on 58 cases of lethal child abuse. Extrapolated to all institutes of legal medicine, this corresponds to 62 cases in all of West Germany in the period studied. An approximately equal number of unreported cases should be added to this figure. Including unreported cases, at least 20 cases of lethal child abuse occurred per year; thus only one in every two cases ever came to light. Almost two thirds of the victims were younger than one year old. At autopsy 59% exhibited signs of repeated abuse at autopsy. By far the most common cause of death was direct impact from a blunt object, usually to the head. Mostly, the male person to whom the victim relates most closely (father, stepfather, partner of the mother) has killed the child. Twenty-one of the 74 persons charged saw the charges against them dropped or were acquitted due to lack of evidence; 51 received sentences ranging from one year probation to life. In the remaining two cases the outcome of the trial was unknown. Signs of abuse were readily apparent at autopsy in almost all cases. The high number of unreported cases underscores the need to educate medical students and practicing physicians to be on the look-out for signs of abuse and argues for an increase in the rate of autopsy.  相似文献   
953.
A young nurse was found dead in her flat. In chemical-toxicological analysis the following femoral blood drug concentrations were determined: paroxetine 0.176 mg/l, doxepine 82.12 mg/l, desmethyldoxepine 0.34 mg/l. Additionally the drug concentrations were determined in various body fluids and organs. The results of the described fatality are discussed. For interpretation of toxicologic results in antidepressant fatalities ratios of parent drug to metabolite and postmortem drug redistribution should be taken into account.  相似文献   
954.
Estimation of time of death (TOD) of white-tailed deer is important to wildlife law enforcement officers. The purpose of this study was to develop and test a model for estimating TOD of white-tailed deer in Missouri. We compare the utility of carcass temperature, pupil diameter, and rigor mortis as TOD indicators. The effects of body size, ambient temperature, and various carcass handling methods on the estimate were also examined. Data were collected from 1484 deer during the 1995-96 and 1996-97 hunting seasons. Stepwise regression indicated that all three indicators were significant and that body size and ambient temperature could influence the model. Predictive equations were developed for various combinations of the indicators based on practicality and statistical probabilities. TOD was estimated for 28 animals where the exact TOD was known. There was no significant difference between the estimated and known TOD (p = 0.759) and the average of the absolute differences in 1 h and 28 min.  相似文献   
955.
This article describes the application of solid-phase microextraction (SPME) to the recovery of manufacturing by-products and impurities from an illicit drug seizure. The preparation chosen for examination using this technique contained 4-methoxyamphetamine, an hallucinogenic amphetamine that has been encountered frequently in South Australia. Compounds found in the PMA preparation included 4-methoxyphenol, 4-methoxybenzaldehyde, 4-methoxyphenyl-2-propanone, 4-methoxyphenyl-2-propanol, 4-methoxyphenyl-propene, and (tentatively) 4-methyl-5-(4'-methoxyphenyl) pyrimidine. The presence of these compounds suggests that the active drug was prepared from 4-methoxybenzaldehyde via 4-methoxyphenyl-2-propanone using a Leuckardt reductive amination. In this instance, SPME was found to be a simple, rapid, and non-destructive recovery technique that gave results complementary to those provided by conventional liquid-liquid extraction. There is an indication that SPME might find application in profiling of illicit drugs.  相似文献   
956.
Beer consumption is commonly an issue in a medico-legal setting, requiring estimates either of a likely blood alcohol concentration (BAC) for a given pattern of consumption or vice versa. Four hundred and four beers and malt beverages available for sale in the State of Washington were tested by gas chromatography for their alcohol content. Considerable variability in the alcoholic strength was found, even within the same class. Overall the range of concentrations was 2.92%v/v to 15.66%v/v. The mean alcohol concentration for ales was 5.51%v/v (SD 1.23%v/v), and for lagers, 5.32% (SD 1.43%v/v). Some specialty brews had characteristically higher or lower mean concentrations: ice beers 6.07%v/v, malt liquor 7.23%v/v, light beer 4.13%v/v, seasonal ales 6.30%v/v. Six brands of lager and four light beers account for the majority of all beer sales in the United States, and the mean alcohol concentration for these products was measured as 4.73%v/v and 4.10%v/v respectively. Few of the beers (17%) were labeled with respect to alcohol content, and in some cases, there was a significant disparity between the concentration listed on the label, and the measured alcohol concentration. Toxicologists need to exercise caution when performing Widmark type calculations, using all available information to select the most appropriate estimate for alcoholic strength of a beer or malt beverage.  相似文献   
957.
958.
One consequence of the drug war has been the incarceration of many offenders who pose a health risk to staff. This article presents an analytical framework to examine the factors that influence staffs' perceptions of the threat of infection. Four risk domains influence an officer's self-rated threat of exposure: (1) psychosocial factors, (2) HIV/AIDS-related knowledge, (3) perception of risk in the prison environment, and (4) risk reduction efforts. Officers with lower levels of education, those who worked with medium and maximum custody inmates, and those who had more high-risk encounters with inmates rated their chances for infection as high. Findings are discussed in light of their practical and theoretical applications.  相似文献   
959.
Histological analysis of the viscera in experimental poisoning with psilocybin-containing mushrooms showed nonspecific changes in all examined organs, presenting as expressed hemocirculatory disorders and intracellular dystrophy. Quantitative histochemical analysis showed appreciable shifts in the activities of enzymes involved in the cytoplasmic and mitochondrial redox processes and of specific enzymes involved in nerve tissue metabolism. This may reflect some features in the direct effects of narcotic alkaloids contained in psilocybin-producing mushrooms.  相似文献   
960.
The index of lethal poisoning with ethyl alcohol and its surrogates in Russia remains one of the highest in the world. It is explained by high alcohol consumption in Russia (about 15 liters of pure alcohol per capita annually), consumption of mainly strong beverages (about 80%), extensive sales of adulterated strong alcoholic beverages (more than 25%), virtually no preventive work in the population, and other causes. The index of lethal poisoning with alcohol and its surrogates in the country and its regions is one of the most important parameters in evaluation of the socioeconomic well-being of the population.  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