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871.
Miller EJ Nelson GM Shultz JJ Davis GG 《The American journal of forensic medicine and pathology》2003,24(1):28-31
Sudden unexplained death in epilepsy occurs when epilepsy patients die suddenly and unexpectedly in the absence of recent tonic-clonic seizure activity. There is currently no known reliable indicator of acutely lethal seizure activity. Clinical studies record a relationship between recent (within 10-40 minutes) seizure activity and elevated serum prolactin levels, and postictal elevation of prolactin within peripheral vessels has proved clinically useful in determining recent seizure activity. The authors hypothesized that elevated prolactin could be detected in cerebral vessels by immunohistochemical stains, serving as a marker for sudden unexplained death in epilepsy. They conducted a retrospective study of individuals who died in their jurisdiction during the 14 years from 1986 through 1999. The study contained one group of individuals who died of sudden unexplained death in epilepsy, a group with epilepsy who died of some other cause, and a control group whose members died rapidly of a gunshot wound of the torso. Sections of hippocampus and neocortex were obtained and stained with a polyclonal prolactin antibody. No significant difference in the level of immunostaining for prolactin in cerebral vessels was found between the experimental and control groups. A review of the protocols used indicates that revision of certain aspects may provide better immunostaining and more conclusive results. 相似文献
872.
Young Black Men and Urban Policing in the United States 总被引:1,自引:0,他引:1
873.
The great demand for esthetic restorations has resulted in placement of large numbers of composite resin fillings. The popularity of these materials is reflected in the quantity and variety of resin brands currently on the market. The ability to distinguish resin brands can aid in positive identification of burn victims, assuming that appropriate dental records exist. Scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) was used to characterize the structure and composition of 10 modern resins. The structure of each resin was unique to manufacturer, and elemental analysis allowed separation into distinct groups. These 10 resins were also placed in extracted teeth and incinerated at 900 degrees C for 30 min, simulating near cremation conditions. The resins were identifiable by SEM/EDS after incineration, and the elemental composition remained almost unchanged. The data produced are immediately useful for resin identification in forensics, and comparative analysis can be readily performed using standard equipment. This work represents the initial stage of database generation. 相似文献
874.
Allard MW Polanskey D Miller K Wilson MR Monson KL Budowle B 《Forensic science international》2005,148(2-3):169-179
The scientific working group on DNA analysis Methods (SWGDAM) mitochondrial DNA (mtDNA) population data set is used to infer the relative rarity of control region mtDNA profiles obtained from evidence samples and of profiles used for identification of missing persons. In this study, the African American haplogroup patterns in the SWGDAM data were analyzed in a phylogenetic context to determine relevant single nucleotide polymorphisms (SNPs) and to describe haplogroup distributions for Africans observed in these data sets. Over 200 SNPs (n=217) were observed in the African American data set (n=1148). These SNPs ranged from having 1-39 changes in the phylogenetic tree, with sites 152 and 16519 being the most variable. On average there were 5.8 changes for a character on the tree. The most variable sites (with 19 or more changes each) observed included 16093, 16129, 16189, 16311, 16362, 16519, 146, 150, 152, 189, and 195. These rapidly changing sites are consistent with other published analyses. Only 34 SNPs are needed to identify all clusters containing 10 or more individuals in the African American data set. The results show that the African American SWGDAM mtDNA data set contains variation consistent with that described in continental African populations. Thirteen of the 18 haplogroups previously observed in African populations were observed and include: L1a, L1b, L1c, L2a, L2b, L2c, L3b, L3d, L3e1, L3e2, L3e3, L3e4 and L3f. Haplogroup L2a is the most commonly observed cluster (18.8%) in the African American data set. The next most common haplogroups in the African American data set include the clusters L1c (11.0%), L1b (9.1%), L3e2 (9.0%) and L3b (8.1%). Approximately 8% of the haplogroups observed within African Americans were common in European Caucasians or East Asians; these were H (n=32), J (n=4), K (n=5), T (n=2), U5 (n=6), U6 (n=9 also known from North Africa), A (n=12), B (n=7), C (n=4), and M (n=16), respectively. The European Caucasian and East Asian haplogroups are expected due to admixture between individuals with recent ancestry in Western Eurasia and sub-Saharan Africa. The genetic characterization of these relevant data sets is fully consistent with other published mtDNA genetic variation. The sequence diversity observed in this data set makes it a valuable tool for forensic applications. 相似文献
875.
Turner WD Brown RE Kelliher TP Tu PH Taister MA Miller KW 《Forensic science international》2005,154(2-3):149-158
Modern forensic facial reconstruction techniques are based on an understanding of skeletal variation and tissue depths. These techniques rely upon a skilled practitioner interpreting limited data. To (i) increase the amount of data available and (ii) lessen the subjective interpretation, we use medical imaging and statistical techniques. We introduce a software tool, reality enhancement/facial approximation by computational estimation (RE/FACE) for computer-based forensic facial reconstruction. The tool applies innovative computer-based techniques to a database of human head computed tomography (CT) scans in order to derive a statistical approximation of the soft tissue structure of a questioned skull. A core component of this tool is an algorithm for removing the variation in facial structure due to skeletal variation. This method uses models derived from the CT scans and does not require manual measurement or placement of landmarks. It does not require tissue-depth tables, can be tailored to specific racial categories by adding CT scans, and removes much of the subjectivity of manual reconstructions. 相似文献
876.
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879.
This paper presents the results of an empirical examination of the methods small business assistance agencies in the Dominican Republic use to overcome technology transfer barriers. The availability and the methods agencies use to access the world's business knowledge are examined, as well as how the agencies disseminate the information to clients. The discussion identifies barriers that inhibit the flow of client information between (1) the knowledge pool and the agencies and (2) the agencies and the client. The strategies that agencies use to overcome barriers are characterized as push or pull, and informal or formal. Pull strategies begin with marketplace need and work toward the technology to solve the problem. Push strategies begin with specific business information and work toward its acceptance and use in the marketplace by clients. Personal interviews were conducted in Spanish with heads of the 13 assistance agencies in the country. Survey participants were asked about the processes, procedures, and techniques they used to gain and transfer business skills. The study identifies specific activities in which the agencies engage in order to effectively overcome barriers to the transfer of business knowledge. 相似文献
880.
This article examines selected Burger Court cases concerningmunicipal antitrust immunity in order to determine whether theU.S. Supreme Court has a theoretical perspective on the relationshipbetween the states and their municipalities. After delineatingthe constitutional position of municipalities through an examinationof key Court cases and Dillon's rule, the study explores thederivative status of state-action immunity to municipalitiesin antitrust suits. In two significant cases, including oneinvolving a home rule city, the Burger Court has refused togrant municipalities the state-action exemption granted statesunder the Sherman Act. But, in reinforcing the unitary relationshipbetween the states and their municipalities, the Court has notaddressed Dillon's rule or the ambiguities inherent in denyingmunicipalities the residual powers of local self-government. 相似文献