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251.
Complex behaviors arising from the sleep period may result in violent or injurious consequences, even death. Those resulting in death may be erroneously deemed suicides. A series of case examples and review of the pertinent literature are provided to increase awareness of the possibility that some apparent "suicides" are the unfortunate, but unintentional, consequence of sleep-related complex behaviors and therefore are without premeditation, conscious awareness, or personal responsibility. The correct cause-of-death determination in such cases may have profound social, religious, and insurance implications for surviving friends and family members.  相似文献   
252.
Age-related changes in tooth color have been described previously, however, the use of dental color for age estimation in forensic odontology has been limited due to the difficulty of measuring color objectively. This study presents an objective method for determining dental color to estimate the age of an individual. Dentine color in 250 teeth from patients ranging in age from 10 to 89 years was determined by spectroradiometry. Color measurements were performed as suggested in the CIE 1931 (International Commission on Illumination). Chromaticity coordinates (x, y, z), luminance (Y), whiteness index (WIC, Z%, WIC) and yellowness index (YI) were obtained. Correlations between these colorimetric variables and aging were established by linear regression analyses. All the variables fit the mathematical model with correlation coefficients ranging from 0.53 to 0.75. This method of color measurement produced an expected associated error of calibration averaging 13.7 years about the mean estimated values, at a 70% level of confidence. Two different multiple regression models for dental age estimation were tested, and variables that made the greatest contributions to age calculation were identified. To determine the effect of postmortem interval on tooth color and its influence in age estimation, 37 teeth obtained from human skeletal remains buried during an interval ranging from 21 to 37 years were also studied. In this material, the correlation between age and dental color measured by spectroradiometry was weaker than in fresh extracted teeth.It is concluded that determination of dentine color by spectroradiometry is a potentially useful objective method to estimate age in forensic studies in combination with other methods.  相似文献   
253.
We report the results of Spanish and Portuguese working group (GEP) of International Society of Forensic Genetics (ISFG) Collaborative Exercise 2001-2002 on mitochondrial DNA (mtDNA) analysis. 64 laboratories from Spain, Portugal and several Latin-American countries participated in this quality control exercise. Five samples were sent to the participating laboratories, four blood stains (M1-M4) and a sample (M5) consisting of two hair shaft fragments. M4 was non-human (Felis catus) in origin; therefore, the capacity of the labs to identify the biological source of this sample was an integral part of the exercise. Some labs detected the non-human origin of M4 by carrying out immuno-diffussion techniques using antihuman serum, whereas others identified the specific animal origin by testing the sample against a set of animal antibodies or by means of the analysis of mtDNA regions (Cyt-b, 12S, and 16S genes). The results of the other three human blood stains (M1-M3) improved in relation to the last Collaborative Exercises but those related to hairs yielded a low rate of success which clearly contrasts with previous results. As a consequence of this, some labs performed additional analysis showing that the origin of this low efficiency was not the presence of inhibitors, but the low quantity of DNA present in these specific hair samples and the degradation.As a general conclusion the results emphasize the need of external proficiency testing as part of the accreditation procedure for the labs performing mtDNA analysis in forensic casework.  相似文献   
254.
Detection of illicit drugs in the environment, particularly in soils, often suggests the present or past location of a clandestine production center for these substances. Thus, development of efficient methods for the analysis and detection of these chemicals is of paramount importance in the field of chemical forensics. In this work, a method involving the extraction and retrospective confirmation of fentanyl, acetylfentanyl, thiofentanyl, and acetylthiofentanyl using trichloroethoxycarbonylation chemistry in a high clay-content soil is presented. The soil was spiked separately with each fentanyl at two concentrations (1 and 10 μg/g) and their extraction accomplished using ethyl acetate and aqueous NH4OH (pH ~ 11.4) with extraction recoveries ranging from ~56% to 82% for the high-concentration (10 μg/g) samples while ranging from ~68% to 83% for the low-concentration (1 μg/g) samples. After their extraction, residues containing each fentanyl were reacted with 2,2,2-trichloroethoxycarbonyl chloride (Troc-Cl) to generate two unique and predictable products from each opioid that can be used to retrospectively confirm their presence and identity using EI-GC-MS. The method's limit of detection (MDL/LOD) for Troc-norfentanyl and Troc-noracetylfentanyl were estimated to be 29.4 and 31.8 ng/mL in the organic extracts. In addition, the method's limit of quantitation for Troc-norfentanyl and Troc-noracetylfentanyl were determined to be 88.2 and 95.5 ng/mL, respectively. Collectively, the results presented herein strengthen the use of chloroformate chemistry as an additional chemical tool to confirm the presence of these highly toxic and lethal substances in the environment.  相似文献   
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257.
Under the traditional socialist central planning system, economic growth in China and Vietnam was unstable and not very satisfactory. Yet, both countries achieved a remarkable progress in the area of human development. Later, under the market socialist model, China and Vietnam achieved very high rates of GDP growth, and malnutrition declined significantly. Yet, income distribution and the provision of key public services deteriorated in both countries. Progress in reducing child mortality in China was relatively slow, before improving in the early 2000s. Although Vietnam is much poorer than China, and has been growing less fast, its record in this area was markedly better. We show that this apparent paradox is due mainly to the fact that the negative side-effects of market-oriented reforms have reached a more advanced and alarming stage in China than in Vietnam. Our results also suggest that an additional factor is constituted by a relatively better status of women in Vietnam with respect to China. However, we also warn that signs are emerging in Vietnam too, indicating that it is entering a stage of development where the social problems now evident in China are starting to manifest themselves on a large and worrying scale. Our policy conclusions advocate in favour of re-establishing (in a new form, compatible with the maintenance of the economic dynamism of the market socialist system) some positive features of the pre-reform socialist model, among which universal public provision of basic public services is paramount.
Alberto GabrieleEmail:
  相似文献   
258.
This article focuses on the Italian and Spanish models of growth and analyses labour market, human capital and innovation policy reforms since the mid 1990s. The comparison with France and Germany shows the constraints that have hindered the rise of institutional complementarities and the competitiveness of the two Mediterranean countries already before the introd uction of the euro and the outbreak of the 2008 crisis. The analysis highlights both similarities and structural differences between Italy and Spain and demonstrates the long-term institutional conditions that explain why the economic breakdown has had such a deep impact on the two countries.  相似文献   
259.
Currently, aluminum stub with carbon adhesive devices are used to collect inorganic gunshot residues (GSR) from the hands of a shooter. In an ideal shooting case, the gunshot particles do not persist for more than 2 h in the hands of the shooter, provided that the hands have not been washed. However, for forensic analysis and inference, the extended persistence of GSR would be desirable. This study investigates a novel GSR sampling and detection protocol. Sampling was performed in the nostrils using swab devices impregnated in ethylenediaminetetraacetic acid (EDTA). The GSRs persisted for longer periods in nasal mucus than on the hands, and particles were detected 6 h after shooting occurred. The analytical determination was conducted by scanning laser ablation-inductively coupled plasma-mass spectrometry (SLA-ICPMS) which enable the identification of the number of particles and their elemental composition. Seventeen isotope signals corresponding to 13C, 205Tl and 15 analytes that are usually associated with the composition of GSR residues were monitored: 27Al, 29Si, 31P, 33S, 35Cl, 39K, 44Ca, 57Fe, 60Ni, 63Cu, 66Zn, 118Sn, 121Sb, 137Ba, and 208Pb. The SLA technique enabled the reduction of the swab analysis time to 40 min. The effectiveness of this methodology was evaluated with two types of firearms: a pistol and a shotgun. The results indicated that the methodology proposed for the analysis of the nasal GSR was effective and that it can improve or complement the forensic analyses and inferences presented in a court.  相似文献   
260.
Better understanding of the timing of fracture healing may help in cases of interpersonal violence but also of personal identification. The intra- and inter-rater agreement for the adapted fracture healing scale (AFHS) assessing the post-traumatic time interval on radiographs were tested. This is a preliminary study, providing essential information on method reliability for upcoming studies using the AFHS. Five raters (two radiologists, a forensic pathologist, an orthopedist, and an anthropologist) were presented with a test in three parts consisting of 85 radiographs (from 30 adults) of fractures of tubular bones in different stages of healing purposefully selected from more than 1500 radiographs. The raters were firstly asked to assess 15 features describing fracture healing as present, absent, or not assessable. Thereafter, the raters were asked to choose from the AFHS a single-stage best representing the observed healing pattern. The intra- and inter-rater agreement were assessed using single-rating, absolute agreement, two-way mixed-effects intra-class correlation (ICC) coefficients. The intra-rater ICC of radiologist 1 ranged from 0.80 to 0.94. The radiologists’ inter-rater ICC ranged from 0.68 to 0.74, while it ranged from −0.01 to 0.90 for the other raters. The good to excellent ICC among the radiologists and forensic anthropologist provides good foundation for the use of the AFHS in forensic cases of trauma dating. The poor to good results for the other physicians indicate that using the AFHS requires training in skeletal anatomy and radiology.  相似文献   
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