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971.
For the purpose of estimating time since death in skeletal remains, postmortem changes in human compact bones were examined by microradiography and electron microscopy. The UV-fluorescence of the peripheral zone of compact bone was also examined by microscopic spectrophotometry. Microradiographic examination revealed no morphological changes in bones left in the open air for long periods, except one of 15 years since death. In bones left in the soil, vacuoles of 5-10 microns diameter, which contained a honeycomb-like structure formed by small vacuoles of 0.5-1 microns diameter, were found in the peripheral zone of the substantia compacta approximately 5 years since death, and in bones of 6 years or more, this change extended to the mid-zone. In bones left in the sea for 4-5 years, vacuoles of 5-10 microns diameter were observed in the outer peripheral zone of the substantia compacta. The relative intensity of UV-fluorescence in bones dwindled with time since death and the correlation coefficient was considerably high. 相似文献
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James H. Svara 《Public administration review》2008,68(1):46-52
Dwight Waldo's conception of the politics–administration question might be better understood as a "relationship" that contains elements of separation and intermixture rather than a "dichotomy," according to this author-commentator.To suggest that Waldo came to support the dichotomy presumes agreement about the meaning of the concept that is missing in Waldo's writings and in the public administration literature. 相似文献
976.
Mary H. Toothman Karen M. Kester Jarrod Champagne Tracey Dawson Cruz W. Scott Street IV Bonnie L. Brown 《Forensic Science International Supplement Series》2008,178(1):7-15
Environmental samples from indoor surfaces can be confounded by dust, which is composed largely of human skin cells and has been documented to contain roughly tens of micrograms of total DNA per gram of dust. This study complements previous published work by providing estimates of the quantity of amplifiable human DNA found in environmental samples from a typical indoor environment, categorized by the intensity of human traffic and visible quantity of dust. Dust was collected by surface swabbing standard 576 cm2 areas in eight locations, and evaluated for total DNA quantity, presence of human DNA (mitochondrial and nuclear loci using conventional PCR), quantity of human nuclear DNA using quantitative PCR, and STR analysis. The total DNA content of 36 dust samples ranged from 9 to 28 ng/cm2, and contained 0.2–1.1 pg/cm2 of human DNA. Overall, human DNA was detected in 97% of 36 dust samples and 61% of samples yielded allele distributions of varying degrees of complexity when subjected to STR analysis. The implications of this study are twofold. First, the presence of dust in evidence can be a significant contamination source in forensic investigations because the human DNA component is of sufficient quality and quantity to produce allele calls in STR analysis. This can be effectively managed by implementing stringent protocols for collection and analysis of potential biological samples. A second implication is the use of dust as a source of evidence for identification of inhabitants within a defined location. In the latter case, a number of additional studies would be necessary to identify relevant pretreatments for environmental dust samples and to develop the necessary deconvolution techniques to separate the composite genotypes obtained. 相似文献
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A simple and reliable previously reported extraction procedure has been extended to the analysis of a wide range of basic and neutral drugs in postmortem blood and other tissues. The method employs 200 microliters of blood treated with water and ammonia and extracted with diethyl ether. The concentrated extract is generally sufficiently clean for direct analysis by gas chromatography and high pressure liquid chromatography. Recovery, precision and linearity data are presented for selected drugs. 相似文献