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991.
The guideline for forensic pathology was prepared by the Forensic Pathology Committee of the College of American Pathologists. The definitional criteria for forensic pathology included in this guideline have been approved both by the House of Delegates and the Board of Governors of the College of American Pathologists. The guideline presents an overview of forensic pathology and an approach to the forensic autopsy and medicolegal death investigation. Emphasis is placed on the role of forensic pathology in maintaining public health, welfare, and safety. The guideline is intended to serve as an educational tool, and its use should be determined by the individual circumstances and settings of specific cases. 相似文献
992.
DL Williams L Spring L Collins LP Miller LB Heifets PR Gangadharam TP Gillis 《Canadian Metallurgical Quarterly》1998,42(7):1853-1857
The contributions of 23 insertion, deletion, or missense mutations within an 81-bp fragment of rpoB, the gene encoding the beta-subunit of the DNA-dependent RNA polymerase of Mycobacterium tuberculosis, to the development of resistance to rifamycins (rifampin, rifabutin, rifapentine, and KRM-1648) in 29 rifampin-resistant clinical isolates were defined. Specific mutant rpoB alleles led to the development of cross-resistance to all rifamycins tested, while a subset of mutations were associated with resistance to rifampin and rifapentine but not to KRM-1648 or rifabutin. To further study the impact of specific rpoB mutant alleles on the development of rifamycin resistance, mutations were incorporated into the rpoB gene of M. tuberculosis H37Rv, contained on a mycobacterial shuttle plasmid, by in vitro mutagenesis. Recombinant M. tuberculosis clones containing plasmids with specific mutations in either codon 531 or 526 of rpoB exhibited high-level resistance to all rifamycins tested, whereas clones containing a plasmid with a mutation in codon 516 exhibited high-level resistance to rifampin and rifapentine but were susceptible to both rifabutin and KRM-1648. These results provided additional proof of the association of specific rpoB mutations with the development of rifamycin resistance and corroborate previous reports of the usefulness of rpoB genotyping for predicting rifamycin-resistant phenotypes. 相似文献
993.
GJ Miller JC Martin KA Mitropoulos MP Esnouf JA Cooper JH Morrissey DJ Howarth EG Tuddenham 《Canadian Metallurgical Quarterly》1996,87(10):4187-4196
Factor VII activity (FVIIc), a risk marker for coronary heart disease, is increased during postprandial lipemia. Factor VII activation accompanies lipolysis of triglyceride-rich lipoproteins, but the nature of this association and whether it is causal remain uncertain. To explore this issue, four patients with homozygous factor XII deficiency, four with complete factor XI deficiency, six with factor IX deficiency, and their respective age- and sex-matched controls were given two isocaloric dietary regimens, one providing on average 136 g fat and the other 19 g fat. Blood was taken before breakfast, immediately before lunch at 195 minutes, and at completion of the study at 390 minutes. All samples for each subject and matched control were assayed as one batch for FVIIc, activated factor VII, and factor VII antigen (FVIIag). Activation of factor VII was observed with the high-fat regimen but not with the low-fat regimen in all controls, factor XII-deficient patients, and factor XI-deficient patients. No factor VII activation was observed during either regimen in factor IX-deficient patients, but a normal postprandial responsiveness of factor VII to dietary fat was restored in one patient who replicated the study after factor IX therapy. Plasma FVIIag was not altered postprandially in either regimen in any group of patients or controls. Factor IX apparently plays an obligatory role in the postprandial activation of factor VII, although the mechanism remains to be determined. 相似文献
994.
995.
996.
The effects of cooperative versus individualistic reward on students' intrinsic motivation were investigated. The controlling aspects of extrinsic reward may be heightened or produce greater ego threat in the individualistic situation when compared with a group situation. We predicted that students in the cooperative social situation would show higher levels of intrinsic motivation. Fifth-grade students from existing cooperative groups were assigned randomly to receive a tangible reward based on either cooperative or individualistic achievement for completing pattern block designs. Cooperation affected intrinsic motivation positively. Students in the cooperative dyad solved the block designs more quickly, interacted positively, and viewed the task as easier than did those in the individualistic situation, and they reported that their peers were helpful. There was little evidence that the controlling functions of reward or ego-threat were factors in producing the outcome. Some evidence supporting the importance of the social nature of cooperation was provided. 相似文献
997.
Episodic heavy drinking among college students: Methodological issues and longitudinal perspectives.
Weingardt Kenneth R.; Baer John S.; Kivlahan Daniel R.; Roberts Lisa J.; Miller Elizabeth T.; Marlatt G. Alan 《Canadian Metallurgical Quarterly》1998,12(3):155
Longitudinal data from 81 undergraduates (47 women and 34 men) were used for concurrent and predictive validation of binge drinking measures. Results suggest relative strengths and weaknesses of different binge definitions. The conventional binge measure of >5 drinks in a row (≥4 drinks in a row for women) yielded higher prevalence estimates and higher sensitivity but less specificity than other quantity-frequency measures using alcohol-related problems as the criterion. Alternative binge measures resulted in lower prevalence rates and sensitivity but higher specificity for alcohol-related problems. Only a subset of students exhibited heavy drinking patterns consistently over time. Such consistent heavy drinking was significantly more strongly associated with increased risk of adverse alcohol-related consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
T Martínez Y Escamilla M Gutiérrez M Bodoque B Scola MF Vega 《Canadian Metallurgical Quarterly》1996,47(2):125-128
Listeria innocua NCTC 11289 was grown aerobically in continuous culture in defined media at 30 degrees C. Both acetate and lactate were produced, the proportion of acetate decreased with increasing dilution rate. Enzymatic analysis showed lactate dehydrogenase was activated 10-fold by fructose-1, 6-bisphosphate. The presence of phosphate acetyltransferase and acetate kinase but not pyruvate oxidase was detected, suggesting the sequential action of phosphate acetyltransferase and acetate kinase to produce acetate from acetyl CoA via acetylphosphate. 相似文献
999.
Ohmic contacts to n-GaN using Ag, Au, TiN, Au/Ti, Au/Mo/Ti, and Au/Si/Ti have been studied. The Fermi level of GaN appears
to be unpinned, and metals and compounds with work functions less than the electron affinity resulted in ohmic contacts. Reactively
sputter deposited TiN was ohmic as deposited. However, Au/Ti, Au/Mo/Ti, and Au/Si/Ti required heat treatments to form ohmic
contacts, with the best being an RTA at 900°C. Ag and Au were shown to diffuse across the GaN surface at T>500°C; therefore,
they are unstable, poor ohmic contact metallizations as single metals. The other contact schemes were thermally stable up
to 500°C for times of 30 min. 相似文献
1000.
SD Shafran J Singer DP Zarowny J Deschênes P Phillips F Turgeon FY Aoki E Toma M Miller R Duperval C Lemieux WF Schlech 《Canadian Metallurgical Quarterly》1998,177(1):252-255
Two patients with the Kennedy's disease (KD) mutation have been identified in the Newcastle Brain Tissue Bank. One of these patients had presenile dementia as a prominent clinical feature, previously undescribed in KD. The pathologic substrate underlying the cognitive changes in this patient included neuronal depletion and gliosis in the hippocampus and subcortical gliosis in the prefrontal region. Immunostaining for macrophage markers showed evidence for subtle corticospinal tract pathology in both cases. In contrast to the molecular pathologic features found in ALS, surviving motor neurons in the two KD cases showed no evidence of ubiquitinated inclusions or alterations in neurofilament phosphorylation. 相似文献