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851.
In the course of a scuffle, a youth of 18 years was struck a single blow across the chest with a golf club. He collapsed dead on the spot. At autopsy, a precisely located and highly distinctive patterned imprint abrasion of the precordial region was revealed providing an excellent match with the weapon. The heart showed multiple internal ruptures and there was a laceration of the lingula of the left lung. Injury to the chest wall was confined to the soft tissues, the rib cage and sternum being intact. We postulate a novel mechanism to explain the cardiac rupture. 相似文献
852.
A G Logvinenko 《Sudebno-meditsinskaia ekspertiza》1990,33(3):21-23
Kinetics of changes in absorption spectra (240-650 nm) of aqueous extracts from bloodstains of considerable age (11 years) was studied. It was stated that at early storage time modification of globin residue goes parallel to oxidation of haem residue and at continuous time (more than 1 year) of solid phase storage of blood films considerable damage of protein and haem with their subsequent destruction occurs. But intensity of these processes is likely to depend on factors of initial environmental exposure of fresh bloodstains. 相似文献
853.
854.
T. G. P. Rogers 《The Political quarterly》1956,27(3):260-269
855.
856.
857.
Ralph Segman 《The Journal of Technology Transfer》1989,14(3-4):46-53
Technology development and transfer are long-time human activities. They precede history and extend to the edges of archeology. This article takes an historical (and, for a few paragraphs, imaginative) view of the application and diffusion of technology as a communication process. It begins with the use, perpetuation, and spread of simple inventions by some animals. The narrative carries through paleolithic and neolithic times showing that, rather than being a relatively modern phenomenon, technology transfer was the means by which our progenitors advanced from dependers upon nature to manipulators of nature, from nomads to cultivators and breeders, and from subsistence farmers to urbanites. In developing the key communications technologies of speech, writing, and translation, humankind accelerated the transfer of the many other technological underpinnings of civilization. The article pays special attention to navigation and the linking role the Arbs played in its development. It also describes the British-American exchange of textile technology first westward across the Atlantic and then eastward. While time, timing, technology, and cast of characters continually change, the basics of communication and technology transfer remain the same. 相似文献
858.
An improved method for the separation of the genetic variants of alpha-L-fucosidase in human semen is described. The method involves, isoelectric focusing in ultrathin-layer PAG containing a mixture of ampholines, pH 5-7 and pH 3.5-9.5, and separator HEPES. The Fu pattern obtained is simple, easy to interpret, and reproducible. The occurrence of fucosidase phenotypes in 189 semen samples from the population of Wuhan was investigated, and the frequencies of the Fu alleles were calculated. 相似文献
859.
V Fineschi M P Picchi M Tassini G Valensin A Vivi 《Forensic science international》1990,44(2-3):225-236
1H-nuclear magnetic resonance (NMR) has been applied to the study of postmortem biochemical changes in perchloric acid extracts of rat skeletal muscle. Several metabolites have been detected and the dependence upon the postmortem time has been considered. The simultaneous quantitative determination of metabolites showing up at very low and very high fields has been suggested to yield a satisfactory delineation of the thanatochronology. 相似文献
860.