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991.
The authors established that special structure of bones in childhood have a significant influence on the fractures of long tubular bones. The formation of unusual fractures shows it. Under condition of low speed of bending in the area of fracture many microfissures are formed, which leads to structural failure of intraosseous microcirculation and osteocytes. 相似文献
992.
Carol K. Lee M.D. F.R.C.P.C. Sarah L. Lathrop D.V.M. Ph.D. 《Journal of forensic sciences》2010,55(1):100-103
Abstract: We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected. 相似文献
993.
Raychelle M. Burks M.F.S. Shari E. Pacquette B.S. Mike A. Guericke B.S. Mark V. Wilson Ph.D. David J. Symonsbergen M.S. Kerry A. Lucas Ph.D. Andrea E. Holmes Ph.D. 《Journal of forensic sciences》2010,55(3):723-727
Abstract: The design and preliminary characterization of a novel sensor for drugs of abuse, DETECHIP®, is described in this proof‐of‐concept note. Combining both colorimetric and fluorimetric assays, DETECHIP® is suitable for lab and field use. More than a conventional spot test which provides a single “yes or no” answer, DETECHIP® provides twenty responses for a more complete characterization of suspect material. This is accomplished by visually noting colorimetric and fluorescent changes of carefully selected dyes upon the addition of test analytes, including drugs of abuse, with respect to controls. Color and fluorescence changes are recorded numerically so that a 20 digit identification code can be constructed for comparison of test analytes and known compounds. DETECHIP® is applicable to a variety of drugs, both plant‐derived and synthetic, addressing the need to use several different spot tests simultaneously for a single sample. 相似文献
994.
Chang Liu B.Sc. Hyun M. Park Ph.D. Maria V. Monsalve Ph.D. David D. Y. Chen Ph.D. 《Journal of forensic sciences》2010,55(4):1039-1043
Abstract: Adipocere is a postmortem decomposition product consisting of mostly a mixture of free fatty acids (FFAs) that are formed because of the hydrolysis of triglycerides in adipose tissues. This article describes a simple and robust method for the extraction, identification, and quantification of FFA commonly found in adipocere using gas chromatography–mass spectrometry (GC/MS). This method was applied to analyze tissues from Kwäday Dän Ts’ìnchí, ancient remains discovered in a retreating glacier in the Tatshenshini‐Alsek Park, British Columbia, Canada in August 1999. The lyophilized tissues were grinded and extracted with hexane. The trimethylsilyl fatty acid derivatives were analyzed by GC/MS, and the relative abundances of myristic acid, palmitic acid, oleic acid, and stearic acid were determined. Milligram per gram levels of saturated fatty acids were found in the tissues of the ancient remains, while the levels of unsaturated fatty acids, such as palmitoleic acid, were found to be negligible. The results provided further evidence of the existence of adipocere found during forensic examination of the Kwäday Dän Ts’ìnchí ancient remains. 相似文献
995.
Mark P. V. Begieneman B.Sc. Frank R. W. Van De Goot M.D. Jan Fritz Rence Rozendaal M.D. Ph.D. Paul A. J. Krijnen M.Sc. Hans W. M. Niessen M.D. Ph.D. 《Journal of forensic sciences》2010,55(4):988-992
Abstract: In the present study, ultrastructural analysis of mitochondrial deposits (black dots within mitochondria) as a method for the detection of early acute myocardial infarction (AMI) was evaluated. In 24 patients with AMI and six controls, analysis was performed in the heart of infarcted patients and noninfarcted controls. In the infarction area in lactate dehydrogenase (LDH)‐diagnosed AMI, the percentage of positive mitochondria was significantly higher compared to corresponding heart tissue in control patients and compared to noninfarcted areas within these patients. Also in patients with a clinically diagnosed AMI but no LDH decoloration, a significant higher percentage of positive mitochondria was found in the left ventricle compared to controls and noninfarcted areas. In patients with AMI, an increase in mitochondria with deposits was found in the infarction area compared to controls and noninfarcted tissue within the same patient, suggesting that electron microscopical changes in mitochondria can be used for the diagnosis of AMI less than 3 h old. 相似文献
996.
Hugo F. V. Cardoso Ph.D. 《Journal of forensic sciences》2010,55(6):1557-1560
Abstract: Three studies have proposed discriminant functions for sex determination from deciduous tooth crown dimensions, and this study tests the existing functions on a sample of 46 Portuguese immature skeletons of known sex, aged from birth to 10 years. Deciduous teeth were measured in their mesiodistal and faciolingual crown dimensions, and percentage of correct allocation accuracy in determining sex using each specific function was determined. Discriminant functions were also calculated from data collected for this study and tested using cross‐validation. Results show poor overall accuracy (33.3–75%) and poor cross‐validation (46.2–60.0%). This is related to low sexual dimorphism in deciduous tooth crown size, as well as differences in degree of sexual dimorphism and in overall tooth size between different samples. For these reasons, deciduous crown size does not seem to show significant forensic value as discriminator of sex, particularly when methods developed on one population are applied to individuals of another population. 相似文献
997.
A new method for the detection of caffeine in blood has been proposed based on the combination of extraction and freezing-out to eliminate the influence of sample matrix. Metrological characteristics of the method are presented. Selectivity of detection is achieved by optimal conditions of analysis by high performance liquid chromatography. The method is technically simple and cost-efficient, it ensures rapid performance of the studies. 相似文献
998.
Anthony A. Braga Andrew V. Papachristos David M. Hureau 《Journal of Quantitative Criminology》2010,26(1):33-53
Boston, like many other major U.S. cities, experienced an epidemic of gun violence during the late 1980s and early 1990s that
was followed by a sudden large downturn in gun violence in the mid 1990s. The gun violence drop continued until the early
part of the new millennium. Recent advances in criminological research suggest that there is significant clustering of crime
in micro places, or “hot spots,” that generate a disproportionate amount of criminal events in a city. In this paper, we use
growth curve regression models to uncover distinctive developmental trends in gun assault incidents at street segments and
intersections in Boston over a 29-year period. We find that Boston gun violence is intensely concentrated at a small number
of street segments and intersections rather than spread evenly across the urban landscape between 1980 and 2008. Gun violence
trends at these high-activity micro places follow two general trajectories: stable concentrations of gun assaults incidents
over time and volatile concentrations of gun assault incidents over time. Micro places with volatile trajectories represent
less than 3% of street segments and intersections, generate more than half of all gun violence incidents, and seem to be the
primary drivers of overall gun violence trends in Boston. Our findings suggest that the urban gun violence epidemic, and sudden
downturn in urban gun violence in the late 1990s, may be best understood by examining highly volatile micro-level trends at
a relatively small number of places in urban environments. 相似文献
999.
Alunni-Perret V Borg C Laugier JP Bertrand MF Staccini P Bolla M Quatrehomme G Muller-Bolla M 《The American journal of forensic medicine and pathology》2010,31(4):326-329
The authors report on a macroscopic and microscopic study of human mandible bone lesions achieved by a single-blade knife and a hatchet. The aim of this work was to complete the previous data (scanning electron microscopy analysis of bone lesions made by a single-blade knife and a hatchet, on human femurs) and to compare the lesions of the femur with those of the mandible. The results indicate that the mandible is a more fragile bone, but the features observed on the mandible are quite similar to those previously observed on the femur. This work spells out the main scanning electron microscopy characteristics of sharp (bone cutting) and blunt (exerting a pressure on the bone) mechanisms on human bone. Weapon characteristics serve to explain all of these features. 相似文献
1000.
Martin Schr?der 《Natur und Recht》2010,3(4):770-778
Die Europ?ische Union und die Bundesrepublik Deutschland sind hinsichtlich des Anbaus gentechnisch
ver?nderter Organismen (GVO) sehr zurückhaltend, w?hrend au?erhalb Europas die Zahl
der angebauten gentechnisch ver?nderten Kulturpflanzen stetig zunimmt. Die Anwesenheit von GVO, die
nicht zum Anbau zugelassen sind, in Saatgut ist deshalb ein wiederkehrendes Problem mit wachsender Bedeutung.
Der Beitrag analysiert die dazu vorliegende Rechtsprechung der Verwaltungsgerichte und demonstriert am jüngsten
Fall der Saatgutkontamination (NK603-Spuren in Maissaatgut) die Anwendung des differenzierten Regelungssystems
des GenTG, das den Vollzugsbeh?rden anspruchsvolle Ermittlungsund Abw?gungspflichten auferlegt. 相似文献