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951.
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
952.
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
953.
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
954.
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
955.
956.
This article provides an overview of the historical and theoretical work on adolescent substance abuse with implications for preventive interventions. The focus is on an illustration of the use of four basic prevention tools: education, competency promotion, community mobilization, and natural care giving.Research interests include mental health, family relations, adolescence, and primary prevention.Research interests include family and social relations, adolescent personality social development. 相似文献
957.
958.
Journal of Youth and Adolescence - 相似文献
959.
960.