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61.
G Addolorato E Capristo AV Greco GF Stefanini G Gasbarrini 《Canadian Metallurgical Quarterly》1998,244(5):387-395
OBJECTIVES: To evaluate the influence of chronic alcohol abuse on body composition and energy metabolism in patients affected by chronic alcoholism (group A) compared with a group of healthy social drinkers (group B). SETTING: A university hospital clinic in Italy. SUBJECTS: A total of 32 alcoholics without clinical or laboratory signs of liver cirrhosis and malabsorption. MEASUREMENTS: Body composition was assessed by anthropometric measurements. Resting energy expenditure (REE) and substrate oxidation rate was measured by indirect calorimetry. Daily caloric intake was computed on the basis of a food diary compiled over 7 days. RESULTS: Alcoholics showed a significantly lower body weight (P < 0.05) and a significant lower fat mass (P < 0.05) compared with controls. A higher waist-to-hip ratio was found in group A than in group B, both as a whole group (P < 0.01) or separated by gender (females, P < 0.01) and males, P < 0.001), indicating a prevalence of fat distribution in the abdominal region in alcoholics. REE was significantly higher in group A than in group B (P < 0.05). The non-protein respiratory quotient was significantly lower in group A than in group B (P < 0.001) with a consequent higher utilization of lipids (P < 0.01) and a lower carbohydrate oxidation (P < 0.05) in group A. The energy intake provided only by food ingestion was found to be significantly higher in group B (P < 0.01), whilst the total caloric intake, computed as food intake plus alcohol intake, was higher in group A (P < 0.01). CONCLUSIONS: Alcoholics, as compared with social drinkers, showed a lower body weight due essentially to a fat mass reduction, a higher REE value normalized by fat-free mass, and a preferential utilization of lipids as energy substrate. These findings might suggest that chronic ethanol abuse is able to determine an impairment of nutritional status due, at least in part, to an alteration of the substrate oxidation. 相似文献
62.
JC Jacquier AV Gorelov DM McLoughlin KA Dawson 《Canadian Metallurgical Quarterly》1998,817(1-2):263-271
Due to the growing interest in the use of cationic surfactants for the construction of liposomal genetic delivery systems, the study of complex formation between DNA and quaternary ammonium detergents is of fundamental importance. In this context, we undertook the study of this complex formation using capillary zone electrophoresis (CZE) with suppressed electroosmotic flow, a technique that allowed us to both monitor the change in mobility of DNA as a function of added surfactant in a precise and reproducible manner and evaluate the potential of CZE to reflect the change in hydrodynamic friction upon binding. Nevertheless, CZE must be applied with caution for binding studies where strong cooperativity occurs, because of the presence of peak splitting at concentrations close to the half-point of binding. Also, a comparison between this experiment and Manning's polyelectrolyte transport properties theory on one hand and Tirado and Garcia de la Torre expression for hydrodynamic friction of rod-like molecules on the other hand is given. 相似文献
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An algorythm of differential diagnosis conduction of the transplant rejection reaction and the diseases caused by herpes viruses in recipients after the kidney transplantation was elaborated, basing on the analysis of results of the clinical, laboratory, immunological and serological examination methods. 相似文献
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U8 small nucleolar RNA (snoRNA) is essential for metazoan ribosomal RNA (rRNA) processing in nucleoli. The sequences and structural features in Xenopus U8 snoRNA that are required for its nucleolar localization were analyzed. Fluorescein-labeled U8 snoRNA was injected into Xenopus oocyte nuclei, and fluorescence microscopy of nucleolar preparations revealed that wild-type Xenopus U8 snoRNA localized to nucleoli, regardless of the presence or nature of the 5' cap on the injected U8 snoRNA. Nucleolar localization was observed when loops or stems in the 5' portion of U8 that are critical for U8 snoRNA function in rRNA processing were mutated. Therefore, sites of interaction in U8 snoRNA that potentially tether it to pre-rRNA are not essential for nucleolar localization of U8. Boxes C and D are known to be nucleolar localization elements (NoLEs) for U8 snoRNA and other snoRNAs of the Box C/D family. However, the spatial relationship of Box C to Box D was not crucial for U8 nucleolar localization, as demonstrated here by deletion of sequences in the two stems that separate them. These U8 mutants can localize to nucleoli and function in rRNA processing as well. The single-stranded Cup region in U8, adjacent to evolutionarily conserved Box C, functions as a NoLE in addition to Boxes C and D. Cup is unique to U8 snoRNA and may help bind putative protein(s) needed for nucleolar localization. Alternatively, Cup may help to retain U8 snoRNA within the nucleolus. 相似文献
68.
A hypothesis on autoregulatory mechanism of reproduction of bone matrix structural changes was proposed resulting from the theoretical study based on author's own data and data documented in literature. This mechanism seems to underly osteoporosis development. All etiological factors of osteoporosis reported were united into a common pathogenetic mechanism on the basis of this conception. 相似文献
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In mice hetero- and homozygotic in relation to the diabetic gene db, it was shown that the regulation of the pancreatic endocrine function by hypothalamus is mediated at least by two mechanisms: neurohumoral one connected with hormone secretion by paraventricular and supraoptical nuclei and by a neuroconductivity mechanism connected with the ventromedial nucleus and lateral hypothalamic area. 相似文献
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