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排序方式: 共有1131条查询结果,搜索用时 31 毫秒
81.
GT Simmons 《Canadian Metallurgical Quarterly》1997,42(4):678-681
Tandem projectiles are unusual events which can cause erroneous case interpretations if one is unfamiliar with them. This paper presents two such cases. The first case involved three .32 caliber bullets, two of which became lodged in a revolver barrel because of faulty ammunition. A third fired bullet subsequently pushed itself and the lodged bullets out of the barrel resulting in a single entrance wound with three bullets in the body. The second case involved a 20 gauge shotgun shell which apparently was inadvertently loaded into a 12 gauge shotgun. This resulted in an unusual entrance wound and unusual X-rays with fragments of the 20 gauge shotgun shell, as well as 12 gauge shotgun shell wadding, being removed from the same wound. The pertinent findings in such cases are discussed so that they may be correctly identified when they occur. 相似文献
82.
FB Vasey 《Canadian Metallurgical Quarterly》1995,82(5):348-351
The controversy over silicone breast implants continues. This review considers evidence on both sides of the issue. Clinical observations suggests consistent chronic fatigue, muscle pain, joint pain, lymphadenopathy, peripheral neuritis and bladder dysfunction syndrome. Epidemiologic studies of defined connective tissue diseases do not show an association, but some studies show a statistical increase in prevalence of symptoms. The author believes symptomatic women should consider having the breast implants removed and not replaced. 相似文献
83.
M Kirkwood D Simmons T Weblemoe J Voyle D Richards 《Canadian Metallurgical Quarterly》1997,110(1055):415-417
AIMS: To assess knowledge and opinions of diabetes among rural Maori elders and spokespersons. METHODS: Interviews were conducted in rural South Auckland. Subjects were identified through their affiliation with one marae (meeting house), residence near the marae and being recognised locally as either male (kaumatua) or female (kuia) elders or spokespersons. The main researcher was a kuia chosen by and from within the local community. Interviews were conducted with 43/44 (98%) subjects identified. RESULTS: While specific diabetes knowledge was low, diabetes was seen, along with cancer, as one of the two major health issues for Maori. Results need to be understood in the context of the holistic understanding of health by Maori. CONCLUSION: The recognition of diabetes as a major health problem was accompanied by a call for diabetes education in a form that will generate interest and participation by Maori. It is timely for the introduction of marae based diabetes awareness and sustained exercise programmes as part of a diabetes prevention and control strategy among Maori communities where diabetes risk is high. 相似文献
84.
L Regli RE Anderson FB Meyer 《Canadian Metallurgical Quarterly》1995,26(8):1444-51; discussion 1451-2
BACKGROUND AND PURPOSE: The use of intermittent reperfusion versus straight occlusion during neurovascular procedures is controversial. This experiment studied the effects of intermittent reperfusion and single occlusion on intracellular brain pH (pHi), regional cerebral or cortical blood flow, and nicotinamide adenine dinucleotide (NADH) fluorescence during temporary focal ischemia. METHODS: Twenty fasted rabbits under 1.0% halothane anesthesia were divided into four groups: (1) nonischemic controls, (2) 60 minutes of uninterrupted focal ischemia, (3) 2 x 30-minute periods of focal ischemia separated by a 5-minute reperfusion, and (4) 4 x 15-minute periods of focal ischemia separated by three 5-minute reperfusion periods. Focal ischemia was produced by occlusion of both the middle cerebral and ipsilateral anterior cerebral arteries. After the final occlusion, there was a 3-hour reperfusion period in all groups. Regional cerebral and cortical blood flow, brain pHi, and NADH fluorescence were measured with in vivo panoramic fluorescence imaging. RESULTS: During occlusion, regional cerebral and cortical blood flows and NADH fluorescence values were not different among the groups. Brain pHi was significantly lower in the 4 x 15-minute group compared with the 1 x 60-minute group (6.57 +/- 0.02 versus 6.73 +/- 0.06; P < .03) but not significant when compared with the 2 x 30-minute group. During the short reperfusion periods, all parameters returned to normal except for NADH fluorescence levels, which remained elevated. During the postischemic final reperfusion period, there was a mild brain alkalosis of approximately 7.1 in all groups. There were no significant differences in NADH fluorescence among groups during the final reperfusion. Regional cerebral and cortical blood flow returned to near normal values in all groups. CONCLUSIONS: This study demonstrates that intermittent reperfusion during temporary focal ischemia has different effects on the intracytoplasmic and the intramitochondrial compartments: worsening of brain cytoplasmic pHi but no significant differences in the oxidation/reduction level of mitochondrial NADH. 相似文献
85.
86.
The following article is Part II of a three-part series on the use of polymer insulating materials in outdoor insulation applications. Despite three decades of service history, polymer insulation materials do not have the same level of standardization as porcelain. As with any technology that is not well standardized, misunderstanding and confusion result, which can influence user selection and application. The objective of this series is to review the benefits of polymer insulating materials. Part II discusses the factors that affect the engineering of materials and addresses the validity of some industry perceptions. A future article will explore some of the material science aspects of silicone elastomer materials by using the case of a hybrid insulator design 相似文献
87.
Yung-Sheng Huang Dave E. Mills Ron P. Ward David F. Horrobin Valerie A. Simmons 《Lipids》1989,24(7):565-571
Weanling male spontaneously hypertensive (SHR) and normotensive (WKY) rats were maintained on a fat-free semisynthetic diet
and killed at various intervals. The effects of fat-depletion on the appearance of essential fatty acid (EFA) deficiency symptoms,
the progressive changes of major fatty acids in plasma, liver, heart, and kidney phospholipids (PL), and in skin total lipids
were compared between these two strains. After five weeks on the diet, the slower growth and the appearance of EFA deficiency
symptoms became evident in SHR. In general, fat-depletion reduced the levels of n−6 fatty acids, whereas it increased those
of 20∶3n−9. However, the fat-depletion induced reduction of 18∶2n−6 in heart PL and 20∶4n−6 in kidney, while the elevation
of 20∶3n−9 in plasma, heart, and kidney PL were greater in WKY than in SHR. As a result, the elevation of biochemical EFA
deficiency index—20∶3n−9/20∶4n−6 ratio—was greater in WKY than in SHR. In comparison with WKY, the concentrations of liver
triacylglycerols and the weights of adipose tissues in SHR were reduced to a greater extent, indicating an active catabolism
of triacylglycerols in SHR. This study suggests that the earlier appearance of morphological symptoms of EFA deficiency in
SHR was not associated with the reducing n−6 EFA levels or with an elevation of triene/tetraene ratio, but possibly to a reduced
supply of n−6 EFA for skin prostaglandin synthesis. 相似文献
88.
Andrew B. C. Yu Glenn Portmann Daryl Simmons 《Drug development and industrial pharmacy》1995,21(16):1827-1840
A hydrolytic acid and base catalyzed ring opening reaction has been demonstrated for a 1,2,4-oxadiazole antiviral compound (WIN 63843) resulting mainly in an amidoxime product. Decomposition products and related impurities were detected using a gradient HPLC method. The hydrolysis reaction was first-order for 35% ethanol/buffer solutions in a 50°C chamber or a light cabinet (1000 ft-candles), the greatest stability being between pH 4 and 6. Furthermore, increasing ethanol concentrations resulted in a great decrease in reaction rates. Therefore, for oral or aerosol solution formulations, light protection, pH control between 4 and 6 and the highest permissible ethanol concentrations would be advantageous. This study has shown that the highly electronegative trifluoromethyl group at the 5 position increases the lability of a 1,2,3-oxdiazole compound. 相似文献
89.
Heat flow has been determined in a borehole near Orlando. Florida and another near Uvalde, Texas. Thermal conductivities in both boreholes were obtained by divided-bar measurements on rock discs and by needle-probe measurements on rock chips. For the needle-probe method, the rock chips were pulverized into powder, saturated with water, and the conductivity of the solid rock was obtained from the conductivity of the mixture by an empirical relationship. Divided-bar measurements for the Florida borehole indicate a heat flow of 0.92 = .03 H.F.U., while needle-probe measurements on rock chips show a heat flow of 1.24 = .06 H.F.U. The discrepancy is attributed to anisotropy of the sedimentary rocks penetrated by the borehole. Heat flow obtained from these two different methods of determining conductivity show good agreement in the Texas borehole. Divided-bar measurements indicate a heat flow of 1.08 = .03 H.F.U. while the chip technique gives a value of 1.13 = .03 H.F.U. 相似文献
90.
The common green fresh water algae Chlorella vulgaris was exposed to starting concentrations of 10 μg/L selenium in the form of selenate, selenite, or selenocyanate (SeCN(-)) for nine days in 10% Bold's basal medium. Uptake of selenate was more pronounced than that of selenite, and there was very little uptake of selenocyanate. Upon uptake of selenate, significant quantities of selenite and selenocyanate were produced by the algae and released back into the growth medium; no selenocyanate was released after selenite uptake. Release of the reduced metabolites after selenate exposure appeared to coincide with increasing esterase activity in solution, indicating that cell death (lysis) was the primary emission pathway. This is the first observation of biotic formation of selenocyanate and its release into waters from a nonindustrial source. The potential environmental implications of this laboratory observation are discussed with respect to the fate of selenium in impacted aquatic systems, the ecotoxicology of selenium bioaccumulation, and the interpretation of environmental selenium speciation data generated, using methods incapable of positively identifying reduced inorganic selenium species, such as selenocyanate. 相似文献