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In using infrared or infrared-enhanced photography to examine gunshot residue (GSR) on dark-colored clothing, the GSR particles are microscopically examined directly on the fabric followed by the modified Griess test (MGT) for nitrites. In conducting the MGT, the GSR is transferred to treated photographic paper for visualization. A positive reaction yields an orange color on specially treated photographic paper. The examiner also evaluates the size of the powder pattern based on the distribution of nitrite reaction sites or density. A false-positive reaction can occur using the MGT due to contaminants or dyes that produce an orange cloud reaction as well. A method for enhancing visualization of the pattern produced by burned and partially unburned powder is by treatment of the fabric with a solution of sodium hypochlorite. In order to evaluate the results of sodium hypochlorite treatment for GSR visualization, the MGT was used as a reference pattern. Enhancing GSR patterns on dark or multicolored clothing was performed by treating the fabric with an application of 5.25% solution of sodium hypochlorite. Bleaching the dyes in the fabric enhances visualization of the GSR pattern by eliminating the background color. Some dyes are not affected by sodium hypochlorite; therefore, bleaching may not enhance the GSR patterns in some fabrics. Sodium hypochlorite provides the investigator with a method for enhancing GSR patterns directly on the fabric. However, this study is not intended to act as a substitute for the MGT or Sodium Rhodizonate test. 相似文献
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Dextromethorphan (DMP), an antitussive, is one of the most popular drugs among the younger generation in Korea. It usually is taken for its hallucinogenic properties and overdoses have been responsible for the fatalities that have been reported frequently. To control the abuse of DMP, the authorities restricted its use through classifying it as a controlled drug on October 2003. The purpose of this study is to provide a standard method for the analysis of DMP and its main metabolite, dextrorphan (DTP) in biological specimens. At first we established a standard operating procedure (SOP) for DMP/DTP in urine, and a method validation was performed. We also quantified DMP from 16 drug abuser's urine samples all of which were positive in the screening test for DMP. For the detection of DMP/DTP, urine samples were adjusted with 6N NaOH (pH 11) and extracted with ethylacetate. Thin layer chromatography was used as the screening test, and the final identification for DMP/DTP was used by GC/MS. The ions (m/z 271 for DMP, m/z 257 for DTP and m/z 86 for lidocaine as internal standard) were extracted from the full scan mass spectrum and were used for quantification. The selectivity, linearity of calibration, accuracy, within- and between day precision, limit of detection and quantification, recovery and stability were examined as parts of the method validation. Extracted calibration curves were linear from 100 to 2000 ng/mL for DMP and DTP with correlation coefficients better than 0.999. Limit detection was 50 ng/mL for DMP and DTP. Within-run precision (%CV) for DMP and DTP at three different concentrations (100, 500 and 1000 ng/mL) was 6.10-18.85%, and between-run precision was 1.70-7.86% for DMP and DTP. Absolute recovery for DMP and DTP was 57-74%, and relative recovery (extraction efficiency) was 80-89%. For 16 drug abuser's urine samples, the concentrations of DMP and DTP were 0.16-52.63 and 0.41-23.75 microg/mL, respectively. Method validation is an important requirement in the practice of chemical analysis, and it will be particularly useful in verifying the reliability of analytical results in the field of forensic science. 相似文献
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Euikon Kim 《East Asia》1992,11(2):35-48
Northeast Asia is a cluster of countries with wide differences in political systems, stages of economic development, levels
of technology, and natural resource endowments. In addition, infrastructures of national economies are mutually complementary.
Yet many sociopolitical elements have so far barred active economic cooperation from becoming a reality, such as North Korean
nuclear issues, different ideologies, unstable political systems, and anti-Japanese sentiments.
The Tumen river Delta area development projects can be a litmus test for future economic cooperation in the region. Market
forces in Japan and South Korea increasingly tend to jump national boundaries and to escape political control, whereas sociopolitical
factors have a tendency to restrict and channel the economic activities. Thus, problems of the Tumen river basin development
lie in how and where those positive and negative factors are reconciled. 相似文献
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Neglect, defined as the failure of a caregiver to adequately provide safety, food, clothing, shelter, education, protection, medical/dental care, and supervision for a child in his/her care, is a relatively uncommon but important cause of child mortality. A retrospective review of pediatric deaths (age 18 years or less) referred to the Medical University of South Carolina Forensic Pathology Office for autopsy over the past 25 years revealed 16 deaths due to some type of pediatric neglect. Cases were analyzed as to age, sex, race, cause and manner of death, autopsy findings, ancillary studies, past medical history, social/family history, and caregiver. Six cases of malnutrition/starvation and/or dehydration were identified, composing the most common cause of death in the neglect cases identified and the majority of the homicides due to neglect. Other deaths in which neglect contributed significantly included toxic ingestions (2 cases), hyper-/hypothermia (2 cases), unusual drowning/aspiration (4 cases), electrocution (1 case), and delayed/absent medical therapy (2 cases, including one of the previously mentioned ingestions). Of these additional cases, 7 were certified as accidental manner, 2 as natural, and 1 as a homicide. Cases which fell into a "gray zone" in which the appropriateness of invoking neglect was a matter of opinion or societal convention were excluded from the review; examples included conventional accidental drowning, choking on food or aspiration of foreign body, overlying/wedging during sleep, accidental hanging, and motor-vehicle traffic accidents (pedestrians, unrestrained passengers). The findings of this review reinforce the fact that malnutrition/starvation and dehydration compose the most common form of lethal pediatric neglect while highlighting less common forms of neglect and the difficulty of determining manner of death in cases in which neglect plays a more questionable role than in seemingly clear-cut malnutrition/starvation and dehydration cases. We demonstrate the typical victim and scenario that investigators will encounter in cases of fatal pediatric neglect, often a child under the age of 1 year who has been deprived of food and/or drink for some time, or an older, more independently mobile child who has not been adequately supervised. These children may or may not have a demonstrable prior history of maltreatment or (nonfatal) neglect, and review of medical records is an important part of the investigation. We additionally discuss key gross autopsy findings, appropriate specimen collection, helpful ancillary studies, microscopic findings of significance, potential mimickers of neglect, and other special considerations in cases of pediatric neglect. 相似文献