全文获取类型
收费全文 | 1403篇 |
免费 | 125篇 |
专业分类
各国政治 | 6篇 |
工人农民 | 12篇 |
世界政治 | 3篇 |
外交国际关系 | 62篇 |
法律 | 1027篇 |
中国共产党 | 7篇 |
中国政治 | 125篇 |
政治理论 | 58篇 |
综合类 | 228篇 |
出版年
2024年 | 6篇 |
2023年 | 19篇 |
2022年 | 37篇 |
2021年 | 25篇 |
2020年 | 50篇 |
2019年 | 43篇 |
2018年 | 37篇 |
2017年 | 49篇 |
2016年 | 40篇 |
2015年 | 45篇 |
2014年 | 89篇 |
2013年 | 99篇 |
2012年 | 94篇 |
2011年 | 107篇 |
2010年 | 103篇 |
2009年 | 111篇 |
2008年 | 100篇 |
2007年 | 114篇 |
2006年 | 71篇 |
2005年 | 43篇 |
2004年 | 48篇 |
2003年 | 49篇 |
2002年 | 41篇 |
2001年 | 32篇 |
2000年 | 16篇 |
1999年 | 5篇 |
1998年 | 10篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 2篇 |
排序方式: 共有1528条查询结果,搜索用时 0 毫秒
801.
Bhawna Dubey M.Sc. P. R. Meganathan M.Sc. Ikramul Haque Ph.D. 《Journal of forensic sciences》2010,55(4):1065-1067
Abstract: Three endangered Indian snake species, Python molurus, Naja naja, and Xenochrophis piscator are known to be significantly involved in illegal trade. Effective authentication of species is required to curb this illegal trade. In the absence of morphological features, molecular identification techniques hold promise to address the issue of species identification. We present an effective PCR–restriction fragment length polymorphism method for easy identification of the three endangered snake species, Python molurus, Naja naja, and Xenochrophis piscator. A 431‐bp amplicon from cytochrome b gene was amplified using novel snake‐specific primers following restriction digestion with enzymes Mbo II and Fok I. The species‐specific reference fragment patterns were obtained for the target species, which enabled successful identification of even highly degraded shed skin sample confirming the utility of the technique in case of poor‐quality DNA. The assay could be effectively used for forensic authentication of three Indian snake species and would help strengthen conservation efforts. 相似文献
802.
Xanth D. G. Mallett Ph.D. Ian Dryden Ph.D. Richard Vorder Bruegge Ph.D. Martin Evison Ph.D. 《Journal of forensic sciences》2010,55(4):1025-1031
Abstract: Faces are assumed to be unique, but their use in court has remained problematic as no method of comparison with known error rates has been accepted by the scientific community. Rather than relying on the assumed uniqueness of facial features, previous research has been directed at estimations of face shape frequency. Here, the influence of age, sex, and ancestry on variation was investigated. Statistical shape analysis was used to examine the necessity for sub‐divisions in forensic comparisons, using a large sample of facial images on which 30 anthropometric landmark points had been placed in 3D. Results showed a clear pattern of separation of the sexes in all age groups, and in different age groups in men. It was concluded that sub‐division of databases by sex will be necessary in forensic comparisons. Sub‐division by age may be necessary in men (although not necessarily in women), and may be necessary by ancestry. 相似文献
803.
Abstract: The dental identification of edentulous individuals can be challenging based on the lack of antemortem materials and unique features visible on radiographs. The constant resorption of the alveolar ridges further complicates the process. The purpose of this study was to quantify the error rate and reliability of dental identifications based on a comparison of synthesized antemortem and postmortem radiographs of edentulous individuals. Ten observers examined ten cases on two occasions and reported dichotomous and conclusion level decisions. These were analyzed using Kappa and Receiver Operator Characteristics. The mean area under the curve was 0.75 and the mean sensitivity was 0.57 and specificity was 0.83. These results suggest that dental identifications of edentulous individuals using radiographs alone have a high error rate and should be dual reported. These data add further weight to the argument that all dental prostheses should be labeled. 相似文献
804.
Abstract: Radiography has long been used by anthropologists to establish positive personal identification of human remains in forensic cases. These methods have been largely ad hoc and depend upon specific congenital or pathological bone markers. Court rulings, such as Daubert and Mohan have, however, pushed the discipline toward more statistically supportable methods of identification. This study describes the use of normal morphological variation of the thoracic vertebrae to identify human remains. Radiographs from healthy, male individuals, aged 18–55 were examined to identify normally varying features of vertebral morphology. The frequency of occurrence of these features was calculated, tested, and found to be stable in the given sample. The frequencies were compared to establish which sets of traits varied independently of one another. Finally, unknown radiographs were compared to known samples to test the applicability of this method in determining positive identification, with 21 of 24 (87.5%) unknown radiographs positively identified. 相似文献
805.
806.
807.
808.
目的利用腭皱数字图像识别系统对正畸治疗前后腭皱形态匹配正确率的分析研究,为法医学中同一认定提供理论依据。方法利用正畸患者治疗前后腭皱形态数字图像,通过腭皱数字图像识别系统对图像的特征进行提取并收录到腭皱数字库,运用Matlab软件完成对腭皱形态数字图像的信息匹配处理。结果正畸治疗前后,个体性检测匹配正确率各自都达到100%。正畸治疗前后腭皱形态匹配正确率为95.67%,配对检验结果 P0.05,具有统计学意义。结论腭皱形态具有高度的个体特异性,正畸治疗后腭皱形态会发生多种变化,但对同一认定的影响不大。腭皱形态识别为法医学同一认定提供一种新的方法和途径。 相似文献
809.
A View to the Future: A Novel Approach for 3D–3D Superimposition and Quantification of Differences for Identification from Next‐Generation Video Surveillance Systems 下载免费PDF全文
Daniele Gibelli M.D. Ph.D. Danilo De Angelis D.S.S. Ph.D. Pasquale Poppa B.Sc. Ph.D. Chiarella Sforza M.D. Cristina Cattaneo B.Sc. M.D. Ph.D. M.A. 《Journal of forensic sciences》2017,62(2):457-461
Techniques of 2D–3D superimposition are widely used in cases of personal identification from video surveillance systems. However, the progressive improvement of 3D image acquisition technology will enable operators to perform also 3D–3D facial superimposition. This study aims at analyzing the possible applications of 3D–3D superimposition to personal identification, although from a theoretical point of view. Twenty subjects underwent a facial 3D scan by stereophotogrammetry twice at different time periods. Scans were superimposed two by two according to nine landmarks, and root‐mean‐square (RMS) value of point‐to‐point distances was calculated. When the two superimposed models belonged to the same individual, RMS value was 2.10 mm, while it was 4.47 mm in mismatches with a statistically significant difference (p < 0.0001). This experiment shows the potential of 3D–3D superimposition: Further studies are needed to ascertain technical limits which may occur in practice and to improve methods useful in the forensic practice. 相似文献
810.
医学会从事医疗损害鉴定之合法性研究 总被引:1,自引:0,他引:1
本文回顾了我国医疗纠纷鉴定体制发展历程,分析了医学会鉴定与司法鉴定的优缺点。在此基础上。认为在现阶段,医学会参与医疗损害鉴定具有一定的、但并不充分的法律依据,具有相对的合法性,医学会应属“准”法定鉴定部门。可以通过最高人民法院制定司法解释或卫生部制定规章的方式使其尽快“转正”。尽管如此,医学会作出的鉴定结论并不具有必然的证明力,其鉴定程序和鉴定书形式等亦应符合法律规定.而鉴定人署名并出庭接受质证是其鉴定结论被法院采信的前提条件。 相似文献