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111.
W De Souza MA Rossi EW Kitajima RR Santos I Roitman 《Canadian Metallurgical Quarterly》1976,22(2):197-203
The fine structure of the promastigotes of Herpetomonas sp. (Leptomonas pessoai) kept in a defined medium at 28 degrees C is described. This portozoon reveals several features in common with other trypanosomatids. A membrane-bounded organelle measuring 0.2 to 0.8 mum in diameter, similar to that described as peroxisome in Crithidia fasciculata, was also observed. A large cavity, located between the nucleus and the kinetoplast and containing vesicles and small particulate material is discussed in this paper. 相似文献
112.
A Georgotas DL Dunner HL Meltzer M Solomon RR Fieve S Gershon 《Canadian Metallurgical Quarterly》1980,15(1):157-163
Diet control of electrolyte intake appears to diminish day to day variation of urinary electrolyte output. Urine sodium concentration is more affected by diet control than potassium, possibly due to the greater variation in sodium ingestion on uncontrolled diets. The coefficient of variation of urinary sodium excretion on the controlled diet was not significantly greater than the variation in sodium ingestion. These experimental results suggest that controlled diets reduce random variation in sodium and potassium excretion and therefore enhance the possibility of observing illness-related biological changes. 相似文献
113.
This paper proposes a qualitative assessment methodology that is comprised of a cluster analysis and an autoregression analysis that assess the effects of various road safety strategies implemented in Hong Kong over the last 10 years. The cluster analysis is first used to group over a hundred road safety projects and programs into a smaller set of meaningful road safety policy strategy clusters. These strategies, together with the trend factor, seasonal pattern, car crashworthiness and meteorological data are then used in the autoregression analysis to relate to the fatality and casualty rates of drivers, passengers, motorcyclists, and pedestrians. This method allows the evaluation of the overall effects of the road safety strategies, and the effects and relative significance of each individual strategy. The evaluation method is described, and the main findings of the study are discussed. 相似文献
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115.
Robert Loo 《Accident; analysis and prevention》1979,11(2):125-127
The paper stressed the study not only of the relationships involving personality dimensions with driver behavior and performance in driving-related tasks, but also of the need to study these relationships in terms of primary personality dimensions or factors. The roles of the primary dimensions of impulsivity, sensation seeking and decision time from Eysenck's extroversion dimension were examined in relation to driver behavior and to the ability to perceive traffic signs. Similarly, the role of decision time in relation to field dependence was examined. 相似文献
116.
Tryptophan metabolism was studied in a family in which a sister and brother had bladder cancer. Urinary tryptophan metabolites after administration of 2 g L-tryptophan were measured in 4 sisters and 1 brother, all free of disease when studied. One sister with and 2 without histories of bladder cancer had significantly elevated levels of kynurenine, acetylkynurenine, and 3-hydroxykynurenine. Administration of 100 mg pyridoxine hydrochloride returned the tryptophan metabolism to normal in these 3 individuals. One brother with a 1 sister without bladder cancer had normal metabolism. A repeat study 2 years later confirmed the abnormal metabolism in the 3 sisters. Two sisters with abnormal tryptophan metabolism were given 200 mg L-kynurenine sulfate orally to bypass the effects of tryptophan oxygenase activity. Both excreted elevated levels of kynurenine and 1 excreted elevated levels of 3-hydroxykynurenine. 相似文献
117.
RR Pfister 《Canadian Metallurgical Quarterly》1983,90(6):601-609
Chemical burns of the eye may destroy all of the corneal epithelium and large portions of conjunctival epithelium into the fornices. Restoration of the ocular surface after a chemical burn depends on the centritedal movement of conjunctival epithelial cells and their adherence to the altered corneal stroma. Epithelial movement after a corneal burn is normal for 72 hours after a burn, but persistent epithelial defects thereafter commonly are not resolved until total corneal vascularization occurs. Although this fresh epithelium may be protected by a bandage soft contact lens, more promising and far-reaching approaches may follow epithelial supplementation and even replacement. The link between the health and integrity of the epithelial layer as it relates to the corneal substratum and its cellular constituents remains to be forged. 相似文献
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