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   2937篇
  免费   118篇
各国政治   222篇
工人农民   111篇
世界政治   182篇
外交国际关系   136篇
法律   1738篇
中国政治   15篇
政治理论   631篇
综合类   20篇
  2023年   17篇
  2021年   18篇
  2020年   54篇
  2019年   64篇
  2018年   85篇
  2017年   113篇
  2016年   101篇
  2015年   69篇
  2014年   74篇
  2013年   384篇
  2012年   73篇
  2011年   103篇
  2010年   73篇
  2009年   71篇
  2008年   84篇
  2007年   83篇
  2006年   88篇
  2005年   83篇
  2004年   90篇
  2003年   85篇
  2002年   69篇
  2001年   79篇
  2000年   66篇
  1999年   62篇
  1998年   42篇
  1997年   34篇
  1996年   41篇
  1995年   20篇
  1994年   19篇
  1993年   25篇
  1992年   42篇
  1991年   50篇
  1990年   48篇
  1989年   54篇
  1988年   48篇
  1987年   43篇
  1986年   48篇
  1985年   40篇
  1984年   29篇
  1983年   27篇
  1982年   18篇
  1981年   32篇
  1980年   17篇
  1979年   28篇
  1978年   28篇
  1977年   29篇
  1975年   18篇
  1971年   21篇
  1970年   20篇
  1968年   23篇
排序方式: 共有3055条查询结果,搜索用时 0 毫秒
131.
132.
Traditionally, toolmark test exemplars are produced by applying a tool's working surface to a piece of soft metal such as lead. Soft, pliable metals are primarily used for this purpose because they will replicate the microscopic grooves present on a tool's working surface without damaging the tool. In this paper the authors present an alternative material for the preparation of test toolmarks. Jewelry modeling or carving waxes are utilized in this study. These waxes are designed for the jewelry modeling industry to create very fine, highly detailed wax models of jewelry pieces that will be cast in various metals utilizing the lost wax casting method. Jeweler's waxes have been found to be ideal for preparing test toolmarks from exemplar tools. The test tool's working surface is applied to a piece of the appropriate wax in a manner consistent with the tool's design. The replicas obtained are exact, highly detailed, 1:1, negative impressions of the exemplar tools working surface, have a long shelf-life, and are suitable for use in toolmark examination and comparison cases.  相似文献   
133.
The technique is proposed allowing quantitation of brain edema and typing of liquor distribution in different parts of brain tissue. In combination with other assays this test can determine a variant of tanatogenesis, detect cause of death and duration of the terminal period. The method application is illustrated by the study of brain hydration in mechanical strangulation asphyxia. It is shown that this death is associated with hypohydration of cerebral structures, especially pronounced in the cortical compartments.  相似文献   
134.
Some causes of ineffective dental care because of the patient's negligence were analyzed. In 16 cases the patients ignored recommendations of the dentist and missed visits to the doctor. As a result, the patients developed complications leading to esthetic dissatisfaction, prolonged treatment, repeated prosthetic management.  相似文献   
135.
We studied 16 sizes of the hyoid bone (HB) from 158 corpses of known gender, Russians, who had died at the age over 15 years by the K. Miller et al program (1998) and 205 back projection electroroentgenograms of the neck of patients of the traumatological hospital in the town of Kirov. HB skeletization was made by the enzymatic drug enzyme. SPSS package and multidimentional statistics (regression and discriminant analyses) were used for data processing. It was established that HB is an informative object of forensic medical personal identification allowing determination of the body length and gender as well as anatomical, x-ray and osteometric individual features. Precision of human body length diagnosis by HB is 6.71-7.26 cm. Therefore, this method should be used in combination with the diagnosis by long tubular bones. Diagnosis of human gender by osteometric signs of HB based on one-dimentional discriminant analysis is feasible in 80-85%, based on canonical discriminant analysis--in 91.1% cases. The method of anatomic, osteometric and roentgenological assessment of HB individuality can be used in personal identification by intravital x-ray of cervical organs and in traumatic defects of HB. The methods may be applied in forensic medical practice in expert examination of body fragments or isolated bone fragments.  相似文献   
136.
137.
An investigation of the following psychoactive drugs: barbiturate, benzodiazepine, meprobamate, methaqualone and phenothiazine, was performed on all automobile occupants killed in accidents in southern Sweden during 1977 and 1978. Of 122 drivers and 55 passengers analysed, low concentrations of these drugs were found in nine drivers and in five passengers. Thus, 7.3% of the drivers were driving under the influence of drugs and, of these, two drivers (1.6% of all analysed drivers) were also inebriated. Twenty-three per cent of the drivers were inebriated only. According to the circumstances in the accidents and the number of drivers whose analyses proved positive, drug influence seldom seems to be the cause of fatal traffic accidents.  相似文献   
138.
A community sample of 610 adults were grouped into those who reported no sexual abuse experience, others who reported noncoercive sexual contact with an individual that was at most 4 years older, and those who reported more severe sexual abuse. The first two groups did not differ from each other on current social support, trauma-specific symptomatology, and somatic complaints whereas the more severe sexual abuse group reported more problems on these dimensions. Further analyses suggested that of the two variables, coercion was more closely associated with problematic outcome than was the existence of an age difference.  相似文献   
139.
140.
Several assays for gamma-hydroxybutyrate (4-hydroxybutyrate, GHB) have been developed based on the enzyme gamma-hydroxybutyrate dehydrogenase (GHB-DH). Enzymatic oxidation of GHB by NAD+ is coupled to diaphorase-mediated reduction of pro-dye to yield colored product. GHB-DH from Ralstonia eutropha was cloned and expressed as a stable fusion protein easily purified by affinity chromatography. Quantitative initial velocity and endpoint versions of the assay in solution are described. Michaelis-Menten parameters for oxidation of GHB and ethanol were estimated. A semi-quantitative "dipstick" version of the assay on paper also is described. Both solution endpoint and "dipstick" assays are sensitive to about 0.05 mg GHB/mL using 10 microL of sample. Ethanol at concentrations possible in urine and agents used to stabilize physiological fluids for forensics analysis do not interfere significantly. The "dipstick" assay also allows detection of GHB in alcoholic beverages after evaporation of about one-fourth drop of beverage before testing. The enzymatic assay for GHB is reliable, sensitive, inexpensive and rapid.  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