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901.
Manual localization of bone fragments on the ground or on complex surfaces in relation to accidents or criminal activity may be time‐consuming and challenging. It is here investigated whether combining a near‐infrared hyperspectral camera and chemometric modeling with false color back‐projection can be used for rapid localization of bone fragments. The approach is noninvasive and highlights the spatial distribution of various compounds/properties to facilitate manual inspection of surfaces. Discriminant partial least squares regression is used to classify between bone and nonbone spectra from the hyperspectral camera. A predictive model (>95% prediction ability) is constructed from raw chicken bones mixed with stone, sand, leaves, moss, and wood. The model uses features in the near‐infrared spectrum which may be selective for bones in general and is able to identify a wide variety of bones from different animals and contexts, including aged and weathered bone. 相似文献
902.
Mindy James Ph.D. Trenna Blagden Ph.D. Ian Moncrief M.S. James P. Burans Ph.D. Katherine Schneider Ph.D. Jacqueline Fletcher Ph.D. 《Journal of forensic sciences》2014,59(2):463-469
The U.S. agricultural sector is vulnerable to intentionally introduced microbial threats because of its wide and open distribution and economic importance. To investigate such events, forensically valid assays for plant pathogen detection are needed. In this work, real‐time PCR assays were developed for three model plant pathogens: Pseudomonas syringae pathovar tomato, Xylella fastidiosa, and Wheat streak mosaic virus. Validation included determination of the linearity and range, limit of detection, sensitivity, specificity, and exclusivity of each assay. Additionally, positive control plasmids, distinguishable from native signature by restriction enzyme digestion, were developed to support forensic application of the assays. Each assay displayed linear amplification of target nucleic acid, detected 100 fg or less of target nucleic acid, and was specific to its target pathogen. Results obtained with these model pathogens provide the framework for development and validation of similar assays for other plant pathogens of high consequence. 相似文献
903.
Carl N. Stephan Ph.D. Brett Amidan M.Sc. Harold Trease M.Sc. Pierre Guyomarc'h Ph.D. Trenton Pulsipher M.Sc. John E. Byrd Ph.D. 《Journal of forensic sciences》2014,59(2):306-313
This paper describes a computerized clavicle identification system primarily designed to resolve the identities of unaccounted‐for U.S. soldiers who fought in the Korean War. Elliptical Fourier analysis is used to quantify the clavicle outline shape from skeletons and postero‐anterior antemortem chest radiographs to rank individuals in terms of metric distance. Similar to leading fingerprint identification systems, shortlists of the top matching candidates are extracted for subsequent human visual assessment. Two independent tests of the computerized system using 17 field‐recovered skeletons and 409 chest radiographs demonstrate that true‐positive matches are captured within the top 5% of the sample 75% of the time. These results are outstanding given the eroded state of some field‐recovered skeletons and the faintness of the 1950's photofluorographs. These methods enhance the capability to resolve several hundred cold cases for which little circumstantial information exists and current DNA and dental record technologies cannot be applied. 相似文献
904.
Emam E. Abdel Fatah Ph.D. Natalie R. Shirley Ph.D. Richard L. Jantz Ph.D. Mohamed R. Mahfouz Ph.D. 《Journal of forensic sciences》2014,59(3):590-600
This study utilizes an innovative 3D approach to discover metric variables that obtain the highest classification rates for sex estimation from the cranium. Models were constructed from 222 cranial CT scans of U.S. Whites from the Bass Donated Collection. These models were used to create a statistical bone atlas that captures the primary shape variation in the skull and facilitates rapid computer‐automated analyses. The bone atlas showed that important size‐related sex variables are bizygomatic breadth, maximum cranial length, cranial base length, and mastoid height. Shape‐related variables capture sex differences in the projection of the glabellar region, inclination of the frontal, and cranial base flexion. In addition, vault thickness is highly dimorphic, with females having on average thicker vaults in the frontal region, and males having thicker vaults in the occipital region. Cross‐validated linear discriminant analysis obtained >95% accuracy (97.5% with 11 variables and 95.5% with eight variables). 相似文献
905.
Presumptive tests for blood play a critical role in the examination of physical evidence and in the determination of subsequent analysis. The catalytic power of hemoglobin allows colorimetric reactions employing phenolphthalein (Kastle‐Meyer test) to indicate “whether” blood is present. Consequently, DNA profiles extracted from phenolphthalein‐positive stains are presumed to be from blood on the evidentiary item and can lead to the identification of “whose” blood is present. Crushed nodules from a variety of legumes yielded phenolphthalein false‐positive reactions that were indistinguishable from true bloodstains both in color quality and in developmental time frame. Clothing and other materials stained by nodules also yielded phenolphthalein false‐positive reactivity for several years after nodule exposure. Nodules from leguminous plants contain a protein (leghemoglobin) which is structurally and functionally similar to hemoglobin. Testing of purified leghemoglobin confirmed this protein as a source of phenolphthalein reactivity. A scenario is presented showing how the presence of leghemoglobin from nodule staining can mislead investigators. 相似文献
906.
Felice Carabellese M.D. Manuela Tamma Psy.D. Donatella La Tegola Psy.D. Ph.D. Chiara Candelli M.D. Ph.D. Roberto Catanesi M.D. 《Journal of forensic sciences》2014,59(2):533-539
In 2006, the Italian National Institute of Statistics (ISTAT) conducted a survey over the entire national territory of women victims of sexual, physical, and psychologic violence, a few years after the first survey, conducted in 2002. For the 2002 survey, respondents were 60,000 women, 22,759 of whom were aged 14–59 years. For the 2006 survey, the sample consisted of 25,000 women aged 16–70 years. Owing to the sensitivity of the issues, the telephone survey technique seems best suited because it provides more anonymity and guarantee of protection. The survey showed that the phenomenon of violence against women is most commonly perpetrated by the partner or ex‐partner, even in cases of homicide. A comparison of the Italian data with those of the U.S.A. for the period 2001–2006 showed a specificity of Intimate Partner Violence in Italy, that seems to be related to cultural elements and psychologic and psychopathologic factors. 相似文献
907.
In this study, we examined creativity in court‐connected mediation. We analyzed 129 mediated agreements from civil cases in Norway and Denmark and compared the outcomes with the parties' original claims to determine whether the agreement addressed only the disputants' demands or contained other elements. If the mediated agreements contained elements in addition to the original claims, we considered them to be “creative.” We devised a creativity scale and found that approximately two thirds of the cases contained creative elements and one quarter of them contained more than five creative elements. We then sought to determine which aspects of the mediation promoted creativity by looking at a variety of mediation characteristics (length of mediation, characteristics of the parties, etc.). We found that lengthier mediations tended to feature more creativity as did cases that involved two private individuals rather than businesses. Cases whose issues involved inheritance as well as the division of property following divorce seemed to foster the highest levels of creativity. Finally, we found that the amount of money at issue also seemed to be relevant: the highest levels of creativity were found in cases in which more money was at stake. In this article, we also discuss the implications of our findings for future research, practice, and training. 相似文献
908.
In this research, we explored the contributions of perceived procedural justice (PPJ) to the conflict management behaviors of adolescents when they experience conflict with their teachers. We tested an extensive model to determine how PPJ contributes to conflict management. We also extended research on PPJ to examine its impact on adolescents. Our results, acquired from a large and diverse sample of 256 high school students, indicate that PPJ had an impact on adolescents' approach to managing conflicts with their teachers. Students who perceived that their teachers' decision processes were just were less dominating and more avoiding, obliging, and compromising. In addition, we found that students' perceptions about the legitimacy of their teachers' authority mediated the relationships between PPJ and conflict management style. This study contributes to the rather scarce research on PPJ's role in conflict management and should be useful for educators searching for constructive, relationship‐based tools for conflict management. 相似文献
909.
Janina Zięba‐Palus Ph.D. Aleksandra Michalska M.Sc. 《Journal of forensic sciences》2014,59(4):943-949
Micro‐Raman spectroscopy was applied to forensic identification of pigments in paint chips and provided differentiation between paint samples. Sixty‐six blue automotive paint samples, 26 solid and 40 metallic were examined. It was found that the majority of the collected Raman spectra provided information about the pigments present. However, in some cases, fluorescence precluded pigment identification. Using laser excitation at longer wavelengths or pretreatment to effect photobleaching often resulted in reduced fluorescence, particularly for solid color samples, and allowed pigment identification. The examined samples were compared pairwise taking into account number, location, and intensity of absorption bands in their infrared spectra. The estimated discrimination power ranged from 97% for solid paint samples to 99% for metallic paint samples. 相似文献
910.
Yun Sik Nam Ph.D. Jin Sook Park M.S. Nak‐Kyoon Kim Ph.D. Yeonhee Lee Ph.D. Kang‐Bong Lee Ph.D. 《Journal of forensic sciences》2014,59(4):1153-1156
Seals are traditionally used in the Far East Asia to stamp an impression on a document in place of a signature. In this study, an accuser claimed that a personal contract regarding mining development rights acquired by a defendant was devolved to the accuser because the defendant stamped the devolvement contract in the presence of the accuser and a witness. The accuser further stated that the seal ink stamped on the devolvement contract was the same as that stamped on the development rights application document. To verify this, the seals used in two documents were analyzed using micro‐attenuated total reflectance Fourier transform infrared spectroscopy and infrared spectra. The findings revealed that the seals originated from different manufacturers. Thus, the accuser's claim on the existence of a devolvement contract was proved to be false. 相似文献