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911.
Abigail S. Bathrick Sarah Norsworthy Dane T. Plaza Mallory N. McCormick Donia Slack Robert S. Ramotowski 《Journal of forensic sciences》2022,67(1):149-160
Forensic examiners must determine whether both latent fingerprint development and DNA profiling can be performed on the same area of an evidence item and, if only one is possible, which examination offers the best chance for identification. Latent fingerprints can be enhanced by targeting different components of fingerprint residues with sequential chemical treatments. This study investigated the effects of single-reagent and sequential latent fingerprint development processes on downstream DNA analysis to determine the point at which latent fingerprint development should be stopped to allow for DNA recovery. Latent fingerprints deposited on copy paper by one donor were developed using three sequential processes: 1,8-diazafluoren-9-one (DFO) → ninhydrin → physical developer (PD); 1,2-indanedione-zinc (IND-Zn) → ninhydrin → PD; and IND-Zn → ninhydrin → Oil Red O (ORO) → PD. Samples were examined after the addition of each chemical treatment. DNA was collected with cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. DNA profiles were obtained with varying degrees of success, depending on the number and type of treatments used for latent fingerprint development. The treatments that were found to be the least harmful to downstream DNA analysis were IND-Zn and IND-Zn/laser, and the most detrimental treatments were DFO, DFO/laser, and PD. In general, as the number of treatments increase, the opportunities for DNA loss or damage also increase, and it is preferable to use fewer treatments when developing latent fingerprints prior to downstream DNA processing. 相似文献
912.
N. C. B. RAY CHAUDHURY 《The Political quarterly》1967,38(3):290-300
913.
Saini V Srivastava R Rai RK Shamal SN Singh TB Tripathi SK 《Journal of forensic sciences》2011,56(Z1):S13-S16
Mandible is the hardest and most durable bone of the skull exhibiting a high degree of sexual dimorphism. Especially ramus of mandible is subjected to greater stress than any other bone of the skull because of the process of mastication. This study has been performed to establish the osteometric standards for practical use in forensic context over Indian population using mandibular ramus. The sample consists of 116 mandibles of Northern Indian population (M:F; 92:24, mean age 37.4 years), collected from the Department of Forensic Medicine, IMS, BHU, Varanasi. Osteometric informations about five metric parameters (coronoid height, projective height, condylar height, and maximum breadth and minimum breadth of ramus) were taken with sliding calipers. These parameters were subjected to different discriminant function analysis using SPSS 16.0. All parameters showed significant sexual dimorphism (p < 0.001 in all cases) with an overall accuracy of 80.2%, and coronoid height was the single best parameter providing an accuracy of 74.1%. 相似文献
914.
The authors have developed a method for molecular-genetic analysis of DNA from isolated cells for the purpose of forensic medical diagnostics. The method is based on the use of the laser capture microdissection (LCM) technology in combination with typing of mitochondrial DNA. Optimization of the conditions for amplification of polymorphic mtDNA loci in preparations containing minimal amounts of the genetic material was accomplished at the initial stage of the work. To this effect, the two-round polymerase chain reaction was employed that allowed the amplified material to be accumulated in the amount sufficient for sequenation. At the next stages, the system thus obtained was tested on the cell model (using isolated cells of human buccal epithelium). It was shown that the proposed method is suitable for the analysis of specific mtDNA characteristics in a single human cell. 相似文献
915.
Shormanov VK Duritsyn EP Prosvetova AP Kim AV Iliushina TN 《Sudebno-meditsinskaia ekspertiza》2011,54(6):27-29
The objective of the present work was to study the distribution of tetramethylthiuram disulfide (TMTD) in the body of warm-blooded animals as exemplified by white rats. TMTD was administered intragastrically and detected in the unaltered form in other internal organs. It was found to accumulate in the largest amounts in the gastric contents, kidneys, and urine. 相似文献
916.
An original test-system for the preliminary quantitative and qualitative evaluation of isolated DNA is proposed by the polymerase chain reaction in real time (PCR-RT) based on the TaqMan technology. This test-system permits to simultaneously measure the amount of DNA in the sample, identify the genetic gender, and detect PCR inhibitors. The method has been approbated in the practical work of forensic medical experts. 相似文献
917.
This study investigated the value of antemortem (AM) and postmortem (PM) radiographs of the claviculae and C3-T4 vertebrae to identify skeletons of missing U.S. soldiers from past military operations. In total, 12 field-recovered skeletons and AM chest radiographs of 1460 individuals were used. For each skeleton, examiners analyzed an array of AM chest radiographs (up to 1000 individuals) and attempted to identify the correct PM/AM radiographic match. When examiners were able to compare all images within a single test, only true-positive identifications were made. When AM radiographs were presented one-at-a-time, in sequential order, and without examiners having knowledge of array size, erroneous identifications resulted but they were almost exclusively made by untrained examiners (accuracy = 35% vs. 90% for trained examiners). This study demonstrates the value of chest radiographs for the identification of disarticulated and even eroded skeletons, but only when methods are wielded by trained examiners. 相似文献
918.
The successful identification of human skeletal remains relies on proven diagnostic techniques for sex determination. This research utilized 608 individuals from South Africa (420 men, 188 women) to conduct a blind nonmetric determination of sex from three features of the distal humerus: olecranon fossa shape, angle of the medial epicondyle, and trochlear extension. A scoring system between males and females was implemented, and the aggregate score of the three features determined the estimated sex of the skeletal element in question. With all features combined, black and white South Africans were categorized successfully as either male or female 75.5% (77% accuracy rate for females, 74% accuracy rate for males). This classification rate is lower than what was found in previous studies, but suggests that characteristics of the distal humerus are still quite valuable when estimating skeletal sex. More research is needed to assess reasons for the differential expression of these traits in different populations and to determine whether the method is nonpopulation specific. 相似文献
919.
920.
Self-control theory (Gottfredson and Hirschi 1990) argues that individuals with similar attributes tend to ‘end up together’ (i.e., homophily) because of the tendency to select
friends based on self-control. Studies documenting homophily in peer groups interpret the correlation between self-control,
peer delinquency, and self-reported delinquency as evidence that self-control is an influential factor in friendship formation.
However, past studies are limited because they do not directly test the hypothesis that self-control influences friendship
selection, nor do they account for other mechanisms that may influence decisions. As a result, it is unclear whether the correlation
between individual and peer behavior is the result of selection based on self-control or alternative mechanisms. To address
this gap in the literature this study employs exponential random graph modeling to test hypotheses derived from self-control
theory using approximately 63,000 respondents from 59 schools from the National Longitudinal Survey of Adolescent Health (Add
Health). In contrast to the predictions made by Gottfredson and Hirschi (1990), and the conclusions drawn from prior research, there is little evidence that self-control influences friendship selection.
The findings are embedded in past work on the relationship between self-control and peer relationships, and implications for
future research are discussed. 相似文献