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961.
962.
ZW Zhang JB Qu GF Xu LH Song JJ Wang S Shimbo T Watanabe H Nakatsuka K Higashikawa M Ikeda 《Canadian Metallurgical Quarterly》1997,208(1-2):81-88
In 1996, 24-h food duplicate samples were collected from two groups of 50 non-smoking women each; one group was in Jinan, the capital city of Shandong Province in China, and the other in a farming village in the Zhangqiu area some 30 km away from the city. The people in the village took significantly more dietary lead (46 micrograms/day) than their counterparts in the city (26 micrograms/day), and blood lead concentrations (35 and 50 micrograms/l for the urban and the rural people, respectively) were in parallel with the dietary lead intake. Search for cereals as the determinants of dietary lead intake and blood lead concentration by multiple regression analysis showed that maize was the most influential source of dietary lead intake among the four common cereals of wheat, rice, foxtail millet (to be called just millet) and maize, whereas millet was the leading determinant of the blood lead level among the four cereals although the influential power was weaker than millet for dietary lead. Lead content in maize (47 ng/g) and millet (47 ng/g) was twice or even more times higher than the levels in wheat (26-30 ng/g) and rice (20-21 ng/g). The significant roles of non-rice/non-wheat cereals such as millet and maize as possible dietary lead sources for farming populations are discussed. 相似文献
963.
GF Longstreth 《Canadian Metallurgical Quarterly》1997,92(3):502-505
OBJECTIVES: Abdominal pain caused by diabetic thoracic polyradiculopathy is unfamiliar to many gastroenterologists. The aim of this study was to describe the clinical characteristics and outcome of the disorder. METHODS: Ten patients (six women) with diabetic thoracic polyradiculopathy were cared for in 20 yr. Electromyographic evidence of nerve root denervation was found in seven patients. Nine patients were followed-up at least until recovery, including four until death. RESULTS: The patients were 42-79 yr of age, had diabetes of various duration, and often had other diabetic complications, including two with previous polyradiculopathy. Pain of various types occurred. It was often worse at night and aggravated by light pressure. Pain was either unilateral or bilateral and was often accompanied by weight loss. All patients had a cutaneous sensory abnormality, and four had localized abdominal wall paresis with protrusion. Spontaneous recovery was documented in nine patients, but two had recurrent polyradiculopathy. CONCLUSIONS: Gastroenterologists should be familiar with diabetic thoracic polyradiculopathy, because its early recognition may prevent unnecessary and expensive diagnostic evaluation for a visceral cause of pain. 相似文献
964.
GF Dobrovol'ski? 《Canadian Metallurgical Quarterly》1997,59(6):35-40
8 etiological variants of subarachnoidal hemorrhage are considered, its complications (rupture into the ventricles, development of the arterial spasm, brain edema) and sequelae (aseptic leptomeningitis, external hydrocephaly). Three stages in the subarachnoidal hemorrhage course are distinguished. The analysis of the vascular alterations and ventricular ependyma in cases of the rupture into the brain ventricles is performed. The study of morphological substrates of the liquor circulation in both macro- and microscopical level is recommended in all cases of subarachnoidal hemorrhage. 相似文献
965.
Tolerance and sensitization to the behavioral effects of cocaine were investigated in rats responding under a fixed-consecutive-number eight schedule of food reinforcement. The development of tolerance or sensitization was induced by delivering the drug either immediately before or after each behavioral session during chronic administration. Chronic cocaine administered before each session resulted in tolerance, as indicated by the shift to the right in the cocaine dose response curve. This tolerance was more likely to develop in the presence of an external discriminative stimulus. On the other hand, when cocaine was delivered after each session, the injections did not disrupt responding and sensitization or increased sensitivity rather than tolerance developed. This sensitization was more likely to occur when the external discriminative stimulus was not present. These data suggest that either tolerance or sensitization to the behavioral effects of cocaine can occur following the same number of chronic injections, with the effect dependent on the context under which the drug is delivered. Significant differences in benzodiazepine receptor binding measured autoradiographically using [3H]flumazenil were observed between rats that received cocaine before or after each session, suggesting that the development of tolerance and sensitization may be mediated through changes in benzodiazepine receptors in discrete brain regions. 相似文献
966.
The effect of lidocaine on the palmitoyl-L-carnitine (PALCAR)-induced mechanical and metabolic derangements was studied in Langendorff rat hearts, perfused aerobically at a constant flow rate and paced electrically. PALCAR (5 mumol/l) increased the left ventricular end-diastolic pressure, decreased the left ventricular developed pressure (i.e., mechanical dysfunction), and decreased the tissue levels of adenosine triphosphate and creatine phosphate (i.e., metabolic change). These mechanical and metabolic alterations induced by PALCAR were concentration-dependently attenuated by lidocaine (20, 50 or 100 mumol/l). Nevertheless, lidocaine (20, 50 or 100 mumol/l) did not affect the mechanical function and energy metabolism of the normal (PALCAR-untreated) heart. These results indicate that lidocaine has a cardioprotective action against the PALCAR-induced mechanical and metabolic derangements. 相似文献
967.
GF Murphy SD Miller DE Kenady W O'Connor DP Wood JW McRoberts WF Gee 《Canadian Metallurgical Quarterly》1994,44(2):273-277
Extra-adrenal pheochromocytomas and paragangliomas are rare tumors of neural crest origin, most commonly found in the retroperitoneum. Because these tumors are so uncommon, relatively little is known about their natural history. Comparisons between adrenal pheochromocytomas and extra-adrenal pheochromocytomas have appeared in the medical literature. Like pheochromocytomas, paragangliomas may occur as functional or nonfunctional tumors. Furthermore, although the hereditary occurrence of pheochromocytomas is well documented, the familial nature of paragangliomas is unclear. We present the first report of a mother and son with nonfunctional paragangliomas occurring in the same anatomic location and describe their care and treatment. 相似文献
968.
PURPOSE: This study evaluates the surface changes and effects on in vitro cell attachment and spreading brought about on prepared commercially pure titanium by multiple exposures to common sterilization methods. MATERIALS AND METHODS: Discs of commercially pure titanium were prepared to approximate the surface roughness of commercially available bone miniplates. Samples underwent sterilization by exposure to ultraviolet light; ethylene oxide sterilization (1, 5, or 10 cycles); or by steam autoclaving (1, 5, or 10 cycles). Representative surfaces from these sterilization groups were examined using a series of surface analytical techniques including scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), and contact angle measurements. Cell attachment assays using murine fibroblasts were then performed on titanium surfaces from each sterilization group and on tissue culture plastic controls. Sterilized surfaces contained O, C, and N contaminants, which affected surface energetics. Mean percent cell attachment values for each group were obtained for periods of up to 1 hour. Representative samples from each group were examined using SEM to ascertain cell spreading and morphology for each sterilization group. RESULTS: Ultraviolet (UV) sterilized surfaces showed no changes from the unsterilized state macroscopically or under SEM. UV surfaces showed cell attachment levels similar to control surfaces at all intervals, and a chronologic progression of cell spreading. Ethylene oxide-sterilized surfaces showed occasional bluish discoloration and a microscopic particulate contaminant, resulting in modest decreases in cell attachment levels without strong correlation to numbers of sterilization cycles. Autoclaved surfaces generally showed the greatest discoloration and heaviest particulate contamination. Cell attachment levels were lower, and cell spreading was diminished compared with the ethylene-oxide-treated group. CONCLUSIONS: Both ethylene oxide and steam autoclave sterilization contaminated and altered the titanium surface, resulting in decreased levels of cell attachment and spreading in vitro. Although corroborative in vivo experiments should be conducted, the results of this study indicate that some multiple sterilization regimens for metallic materials may pose serious biologic concerns. 相似文献
969.
Canadian voters' reasons for following political events were assessed prior to the 1992 Constitutional Referendum and the 1993 federal election. Results showed that reasons reflecting identification were endorsed more frequently than those reflecting introjection, and distinctive patterns of cognitions, emotions, and actions were associated with the 2 types of internalization. Identification was associated with actively seeking information about political events, possessing a complex set of political attitudes, and being more likely to actually vote. Introjection was associated with relying on the influence of important others, experiencing conflicted emotions about political outcomes, and vulnerability to persuasion. The study also provided evidence that identification and introjection toward politics are distinguishable from intrinsic motivation and amotivation. 相似文献
970.