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   3681篇
  免费   227篇
各国政治   368篇
工人农民   220篇
世界政治   437篇
外交国际关系   258篇
法律   1882篇
中国共产党   3篇
中国政治   16篇
政治理论   697篇
综合类   27篇
  2023年   54篇
  2022年   35篇
  2021年   72篇
  2020年   119篇
  2019年   157篇
  2018年   193篇
  2017年   258篇
  2016年   220篇
  2015年   151篇
  2014年   206篇
  2013年   629篇
  2012年   183篇
  2011年   159篇
  2010年   95篇
  2009年   88篇
  2008年   141篇
  2007年   149篇
  2006年   122篇
  2005年   108篇
  2004年   116篇
  2003年   107篇
  2002年   82篇
  2001年   70篇
  2000年   67篇
  1999年   35篇
  1998年   33篇
  1997年   28篇
  1996年   15篇
  1995年   23篇
  1994年   16篇
  1993年   17篇
  1992年   17篇
  1991年   15篇
  1990年   9篇
  1989年   9篇
  1988年   7篇
  1987年   9篇
  1985年   7篇
  1984年   7篇
  1983年   7篇
  1982年   6篇
  1978年   5篇
  1975年   4篇
  1974年   6篇
  1972年   6篇
  1971年   4篇
  1968年   4篇
  1967年   6篇
  1966年   5篇
  1965年   4篇
排序方式: 共有3908条查询结果,搜索用时 31 毫秒
231.
The use of Japanese swords for homicidal attempts is rare. A Japanese samurai sword is a sharp and cutting object. When faced with the use of this weapon, one must distinguish between stabs and incised wounds. Incised wounds can rarely lead to death, but because of the size of the weapon, stabs usually cause much more serious injuries. Stabs also imply a penetrating movement, whereas incised wounds can be the consequence of protective circular blows. Therefore, it is important to distinguish clinically between these two kinds of wounds. We report a case where the perpetrator argued he had given a circular blow, unfortunately hitting the victim. The pieces of evidence are discussed.  相似文献   
232.
This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries.  相似文献   
233.
234.
Improvements in detection limits/sensitivity and lower sample consumption are potential benefits of reducing PCR reaction volumes used in forensic DNA typing of crime scene samples. This premise was studied first with experimental mixtures and a nine-loci megaplex, which demonstrated stochiometric amplification and accurate detection. Next, adjudicated casework samples were subjected to amplification under 15 different template DNA to PCR reaction volume ratios. Reduction of PCR reaction volume and DNA down to 10 microL and 0.500 ng, respectively, produced identical profiles with the same signal intensity and heterozygous allele peak height ratio (HR). Reduction to 5 microL and 0.063 ng yielded HR values that were slightly affected in one to three STR loci. PCR reaction volume reduction can enhance detection and sensitivity while reducing the consumption of irreplaceable crime scene samples.  相似文献   
235.
Two species of blow flies (Diptera: Calliphoridae) were reared on tissues from rabbits administered different dosages of morphine. These species, Protophormia terraenovae and Calliphora vicina are among the first wave of insects colonizing a dead body. Two series of 3 rabbits were given dosages of 10, 20, and 40 mg/h of morphine over a 3 h period via ear artery perfusion. A morphine blood level plateau was attained after 1 h of perfusion. Two other rabbits were used as controls. Samples of tissues collected from rabbits using a coelioscopic technique were determined to have morphine concentrations similar to those encountered in human overdoses and were correlated with dosages of morphine administered. All samples from control rabbits were negative for morphine. Larvae and puparia of both species were regularly collected from each rabbit for toxicological analysis. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were significantly lower than concentrations found in the tissues. There was a decrease in concentration in morphine observed in transition from feeding 3rd instar larva to puparium. A correlation between larval concentration and tissue concentration was found only in feeding 3rd instar larvae.  相似文献   
236.
Initially Norwegian climate policy was very ambitious and Norway stood forth as a pusher on the international scene. Over time Norwegian policy has become more sober, stressing the need for differentiated commitments and flexible implementation. In contrast to the initial enthusiastic phase, climate change policy has been increasingly seen in pragmatic economic terms. Still, Norway is no laggard, as it has shown more willingness to pay for abatement measures than many other countries.  相似文献   
237.
A case of fatal cranial injuries caused by an angle grinder is reported. The scalp lesions were typical of those produced by a cutting disk in a side-slipping movement. On the cranial vault were two bony losses of substance, one of which was deep enough for intracranial penetration of the disk. Signs of deflection of the disk, identical to those found on the scalp, were observed on the external bony table. Because of the circumstances in which the victim was discovered, in particular the damage to the machine which had a broken handle, and the lack of any indication of homicide or suicide, an accident is the most likely hypothesis.  相似文献   
238.
The use of commercial explosives is an unusual method of commiting suicide, and only a few cases have been described in the medicolegal literature. In this paper, two cases of suicide are considered that reflect backgrounds of financial problems and psychological illnesses, respectively. Both individuals comitted suicide by detonating an explosive (fireworks). In the first case putting the explosive on his head and in the second case into his mouth. In both cases the cause of death was the destruction of the central nervous system. The following cases emphasize the importance of the forensic pathologist in the recognition of the scene, as well as the systematical collection of trace evidence of the explosion for their subsequent study in the laboratory and their correlation with the autopsy findings.  相似文献   
239.
Morphine was detected by immunohistochemistry on sections of third stage larvae of Calliphora vomitoria (Diptera, Calliphoridae) reared on minced beef meat previously treated with morphine hydrochloride. The detection was performed with an avidin-biotin-peroxidase-complex method. Positive specimens showed specific staining of the haemolymph and a more intense immunoreaction in an area located at the limit between exocuticle and endocuticle. These results constitute an evidence of morphine accumulation inside the cuticle of Diptera larvae during their development. During the pupariation, the larval cuticle is transformed into the sclerotized puparium. This study consequently points out the possibilities of analyzing empty pupariae when suitable tissues or living necrophagous insects are absent.  相似文献   
240.
Diabetes mellitus is a chronic metabolic illness responsible for a great number of deaths. In postmortem diagnosis, because of the difficulty involved in interpreting blood glucose levels and relatively nonspecific pathologic features, biochemical markers in vitreous humor are useful. The aim of this study was to compare the results obtained for the combined determination of lactate and glucose with fructosamine levels recorded in the vitreous humor of two diagnostic groups (one diabetic and the other nondiabetic). The authors intended to ascertain the capacity of different markers measured in vitreous humor to diagnose diabetes mellitus. Fifty-one cadavers (mean age, 58.7 years; standard deviation, 17.09) were studied. The mean postmortem interval was 16.4 hours (standard deviation, 9.05). Cases were assigned to two diagnostic groups according to whether they were previously diagnosed as either diabetic or nondiabetic. Statistically significant differences for glucose, fructosamine, and the sum values of glucose and lactate were found between the two diagnostic groups. The highest levels were obtained in the group of cases with a previous diagnosis of diabetes mellitus. After the comparison of receiver operating characteristic curves, the sum values of glucose and lactate in vitreous humor is a better predictor of antemortem diabetes mellitus than the fructosamine.  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