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91.
The morphologic changes of the closed injured brain of rats were observed by SEM. The rats either died immediately after conclusive injuries or were killed after 5 minutes to 5 days after injuries. The main changes were as follows: the diffuse disorder, twist, wave-like distortion and break of neuron fibers; axonal swelling; formation of axonal retraction balls; stripping and denotation of myelin sheath The ball-like swelling of neuron, break of neuron membrane and vascular wall, and microthrombus formations were also observed. These damages worsened with prolongation of surviving time of the rats. The axonal retraction ball appeared 8 hours after the injury and was approximately 3-5 cm in diameter, and developed to 7-8 cm after 3-5 days. It is observed that frontal lobe, cerebellum and brain stem were severely damaged. 相似文献
92.
Pathological changes of pancreas in 22 cases died of intoxication were studied and the mechanism was discussed. The results showed that: in death cases by eating of toxicants, the hemorrhage and necrosis of pancreas is extensive mainly in caput and corpus, while inhaling of carbon monoxide is focal in corpus and cauda. 相似文献
93.
Polymorphism and haplotype study of Y-chromosomal multi-STRs loci in Han population in Guangzhou 总被引:2,自引:0,他引:2
Using polymerase chain reaction and silver stain, polymorphism and haplotype study of Y-chromosomal multi-STRs loci: DYS19, DYS389I/II, DYS390 were studied. 111 samples of male were collected from Guangzhou area. 5 alleles were determined in DYS19 locus, 4 alleles in DYS389I locus, 5 alleles in DYS389II locus and 5 alleles in DYS390 locus. Compared with other racial populations, differences of distribution of allele frequencies existed significantly. 72 haplotype were present in this study. 相似文献
94.
The Fx5 Fibre Finder has been developed by Foster & Freeman Ltd to automatically search tape lifts for coloured fibres specified by the operator. Experiments and casework studies have been conducted to assess primarily the performance of the instrument but also, where possible, to compare it with manual searching. Tape lifts have always been manually searched at this laboratory and it is a laborious task. The use of a machine such as the Fx5 would release a scientist from many hours of low power microscopy to be free for other duties and therefore could be a valuable labour saving device in forensic textile examination. 相似文献
95.
Taphonomy of marine environments has been studied mostly from individual cases. The formation of adipocere, or "grave-wax," is an important indicator of the postmortem interval. In the present paper, the conditions and the timing of adipoceric formation are observed in a series of 15 cadavers recovered at different times, over a period of 433 days, from the same contained environment. Initial foci of adipocere on the subcutaneous tissue of the cadavers were detected as early as 38 days from the time of immersion in cold (10-12 degrees C) sea water. The discrepancies between our findings and previous reports on the correlation between time since death and decomposition stages in marine environments are discussed. 相似文献
96.
The chemical substances of perspiration found in latent fingerprint residue may hold the key for dating latent fingerprints. To study the chemical transformations of these components as a function of time and environment, fingerprint residues from four males and four females were analysed by thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC). Three major and two or three minor components were detected by both methods and the variation in the quantity of the major components with time was observed. 相似文献
97.
In July 2005, the Little Rock, Arkansas, school district implemented a new policy to reorganize its management structure in order to create a more efficient bureaucracy. Using Richard Matland’s ambiguity‐conflict model of policy implementation, the authors examine the implementation of this school reorganization policy. Interviews and surveys were conducted with the superintendent and his executive assistants, school principals, teachers, and staff. In line with Matland’s model, the findings suggest that successful implementation is directly related to the policy characteristics of ambiguity and conflict. However, the authors point to the importance of recognizing particular characteristics for different groups of stakeholders within the policy implementation process. Discrepancies among groups of policy actors in the degree of policy ambiguity and policy conflict lead to strikingly different implementation strategies. 相似文献
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Determination of methamphetamine and amphetamine in hair was performed by gas chromatography/mass spectrometry using stable isotope-labeled internal standards, 2-methylamino-1-phenylpropane-2,3,3,3-d4 and 2-amino-1-phenylpropane-2,3,3,3-d4. Extraction of hair with methanol/5M hydrochloric acid (20:1) using ultrasonication was chosen as the standard method. The calibration curves for amphetamines in the hair were linear from 1 to 100 ng/mg (r greater than 0.99). The detection limit was 0.5 ng/mg at the 95% confidence level. The coefficients of variation (CV) (n = 8) of analysis using the spiked hair with methamphetamine were from 0.7 to 6%. The CV (n = 8) of analysis of the methamphetamine abuser's hair was 17.5%. Sectional analysis of monkey and human hair after methamphetamine ingestion suggested a good correlation between the duration of drug use and drug distribution in the hair. 相似文献