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931.
This study presents the fatal case of a young man who was admitted to the ICAU due to sudden cardiac arrest. An interview revealed that the patient had taken some unspecified crystals. From the moment of admission, his condition deteriorated dramatically as a result of increasing circulatory insufficiency. After a few hours, sudden cardiac arrest occurred again and the patient was pronounced dead. In the course of a medicolegal autopsy, samples of biological material were preserved for toxicology tests and histopathological examination. The analysis of samples using the LC‐MS/MS technique revealed the presence of α‐PVP in the following concentrations: blood—174 ng/mL, urine—401 ng/mL, brain—292 ng/g, liver—190 ng/g, kidney—122 ng/g, gastric contents—606 ng/g. The study also presents findings from the parallel histopathological examination. Based on these findings, cardiac arrest secondary to intoxication with alpha‐PVP was determined as the direct cause of the patient's death.  相似文献   
932.
A rapid colorimetric method for detection of p‐phenylenediamine (PPD) in various biological samples is developed. The o‐cresol test for acetaminophen detection has been modified to detect PPD in blood, urine, gastric contents, and liver. After precipitating protein with trichloroacetic acid solution (2 mL, 10% w/v), biological specimens were required to convert PPD metabolites to PPD by acid hydrolysis. Finally, o‐cresol solution (1 mL, 1% w/v), hydrogen peroxide (200 μL, 3%v/v), and concentrated ammonium hydroxide (0.5 mL) were added in the biological samples. The presence of PPD was indicated by formation of violet color which was turned to bluish green color within 10–15 min. The limit of detection was found to be 2 mg/L in blood, urine, and gastric contents and 2 mg/Kg in liver. This method is also free from any potential interference by p‐aminophenol, acetaminophen, and other amine drugs under test conditions. This method was successfully employed to thirteen fatal cases of PPD poisoning.  相似文献   
933.
Crime scene investigators and laboratory analysts use chemical tests to detect and differentiate body fluids. Testing often requires a sample of the stain, and the chemicals may cause degradation of the fluid or interfere with subsequent tests. Colorimetric chemical tests do not differentiate between different types of the same fluid, such as venous and menstrual blood, and there is no presumptive test available to simultaneously differentiate several body fluids. In this study, we recorded ATR FT ‐IR spectra of venous and menstrual blood, semen, saliva, and breastmilk. Neat and simulated casework body fluid samples were analyzed on cotton, nylon, wood, paper, and glass substrates. Differences in fluid composition, including proteins and small molecules, resulted in spectral differences. Venous and menstrual blood is differentiated by the peak at 1039 cm?1 attributed to phosphoric acid found in menstrual blood. Peak intensity is influenced by the porosity and weave of the substrate fabric.  相似文献   
934.
Trace DNA is often found in forensic science investigations. Experience has shown that it is difficult to retrieve a DNA profile when trace DNA is collected from clothing. The aim of this study was to compare four different DNA collection techniques on six different types of clothing in order to determine the best trace DNA recovery method. The classical stain recovery technique using a wet cotton swab was tested against dry swabbing, scraping and a new method, referred to as the mini‐tape lifting technique. Physical contact was simulated with three different “perpetrators” on 18 machine‐washed garments. DNA was collected with the four different DNA recovery methods and subjected to standard PCR‐based DNA profiling. The comparison of STR results showed best results for the mini‐tape lifting and scraping methods independent of the type of clothing. The new mini‐tape lifting technique proved to be an easy and reliable DNA collection method for textiles.  相似文献   
935.
Poisoning with volatile substances remains exceptional. Authors report the case of a married couple who were found in a car with a butane gas bottle: the woman was dead and her husband alleged it was an unsuccessful suicide pact. A specific research of volatile substances on postmortem samples with headspace gas chromatography–mass spectrometry following a quantitative determination was performed. The n‐butane concentrations detected were composed of 610 μg/L (cardiac blood), 50 μg/kg (brain), 134 μg/kg (lungs), 285 μg/kg (liver), and 4090 μg/kg (heart) and were compatible with the rare lethal concentrations evoked in the literature. The cause of death was determined to be asphyxiation through n‐butane criminal poisoning. Authors recommendation therefore is to take samples immediately and place them in properly sealed containers and hence analyzing the samples as soon as possible after collecting them or storing them under ?30°C (?22°F) if analyses cannot be performed immediately.  相似文献   
936.
Lip print analysis, or cheiloscopy, has the potential to join fingerprints and retinal scans as an additional method to determine human identification. This preliminary study sought to determine agreement among 20 raters, forensic odontologists, using an often referenced system that categorizes lip prints into six classes related to the dominant pattern of vertical, horizontal, and intersecting lines. Lip prints were taken from 13 individuals, and raters categorized eight distinct regions of each print. In addition to ratings made while viewing the actual prints, the raters repeated the exercise using photographs of the lip prints. Multirater kappa, a chance‐corrected measure of agreement, ranged between 0.15 for the actual prints and 0.25 for the photos, indicating only poor to fair levels of inter‐rater reliability. While these results fail to support the use of lip prints for human identification, it is possible that more intensive training may yet produce adequate levels of reliability.  相似文献   
937.
Methadone‐related fatalities occur rarely in infants under 1 year, with five confirmed cases in the literature. The interpretation of pediatric postmortem toxicology relies on adult data; however, infants have crucial physiological differences that may impact interpretation of results. Retrospective case review included scene investigation, interviews, autopsy, and NIH/CDC Sudden Unexplained Infant Death Investigation Reporting Form. Methadone levels were confirmed by liquid chromatography/tandem mass spectrometry (LC‐MS/MS). The fatal blood methadone levels in this case series ranged from 69 to 700 ng/mL. This review of the literature adds toxicological findings of three methadone‐related infant fatalities and reviews the current literature on methadone‐related death in infants under 1 year. With opioid use on the rise in today's society, forensic experts should have a high index of suspicion for the possibility of intentional or unintentional poisoning in infants.  相似文献   
938.
We aimed to describe the demographic profile of self‐inflicted harm (SIH) in Los Angeles County between 2001 and 2010 and to investigate trends over this 10‐year period. We used the California Hospital Discharge Data to investigate all cases of hospital admission due to SIH, including suicide attempts and if they had a concurrent psychiatric diagnosis based on ICD‐9 codes. African‐Americans (AA) had the highest 10‐year SIH admission rates. SIH admission rates remained steady throughout the 10‐year study period. Median age of SIH was significantly lower in Latinos. Episodic mood disorders were the most common psychiatric comorbidity. The use of solid/liquid poisoning was the most common SIH method among all racial/ethnic groups. We found major disparities in SIH admissions across racial/ethnic subgroups. The importance of programs to identify, prevent, and treat SIH in these groups is discussed.  相似文献   
939.
Together with the increase in the number of public‐private contracts, recent years have seen a marked proliferation in public‐private arbitrations. This article explores the public interest implications which may arise in such arbitrations and examines how public‐private arbitration is treated under English law. We argue that, due to the lack of a developed administrative law sphere in England and the historical development of arbitration as an exclusively private mode of dispute resolution, the current legal framework of arbitration in England has developed around the private law paradigm of a commercial dispute involving private actors. This private law paradigm results in a conceptual and legal void in respect of how public interest is accounted for, and protected, in arbitrations involving public bodies under English law. Therefore, we suggest that English arbitration law needs to be amended to adequately protect the private interest in public‐private arbitration.  相似文献   
940.
The overlay of a skull and a face image for identification purposes requires similar subject‐to‐camera distances (SCD) to be used at both photographic sessions so that differences in perspective do not compromise the anatomical comparisons. As the facial photograph is the reference standard, it is crucial to determine its SCD first and apply this value to photography of the skull. So far, such a method for estimating the SCD has been elusive (some say impossible), compromising the technical validity of the superimposition procedure. This paper tests the feasibility of using the palpebral fissure length and a well‐established photographic algorithm to accurately estimate the SCD from the facial photograph. Recordings at known SCD across a 1–10 m range (repeated under two test conditions) demonstrate that the newly formulated method works: a mean SCD estimation error of 7% that translates into <1% perspective distortion error between estimated and actual conditions.  相似文献   
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