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91.
OBJECTIVE: To determine the plasma glucose and insulin responses of various doses of glucose, sucrose, fructose and white bread in normal human subjects. DESIGN: Plasma glucose and insulin were measured before and at various times after 8 subjects ate 13 different test meals in randomized order on separate days after an overnight fast. Test meals consisted of 500 ml of tea or water to which was added either nothing, 25, 50, or 100 g of glucose or sucrose, 25 or 50 g fructose, 50 g glucose plus 50 g fructose, or a 25, 50 or 100 g carbohydrate portion of white bread. The glycaemic (GI) and insulinaemic index (II) values of the sugars were calculated by expressing the incremental areas under the plasma glucose and insulin curves (AUC) after glucose, sucrose and fructose as a percentage of the respective AUC after white bread containing the same amount of carbohydrate. SETTING: University teaching hospital clinical nutrition centre. SUBJECTS: Lean, normal subjects (4 male, 4 female) 21-33 y of age. RESULTS: Plasma insulin responses increased nearly linearly as carbohydrate intake increased from 0 to 100 g, but glycaemic responses increased by only 68% and 38% as carbohydrate intake increased from 25 to 50 g and 50 to 100g, respectively. The GI and II values of glucose, 149+/-16 and 147+/-18, respectively, were significantly greater than those of bread (100; P<0.05), while the values for fructose, 16+/-4 and 22+/-3 were significantly less than those of bread (P<0.001). GI values did not differ significantly from II values. CONCLUSIONS: It is concluded that, in normal subjects, as carbohydrate intake is increased from 0 to 100 g, plasma insulin responses increase at a greater rate than plasma glucose responses. The insulinaemic responses elicited by glucose, sucrose or fructose are similar to those that would be expected from a starchy food with the same glycaemic index.  相似文献   
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OBJECTIVE: The prevalence of mental illness and substance abuse in homeless populations has been studied primarily in large urban areas. This study examines a sheltered homeless population in two counties of lower-density population, Dauphin and Cumberland counties in central Pennsylvania, to assess the prevalence of mental illness and substance abuse. METHODS: A total of 81 homeless adults from nine emergency shelters were interviewed using a structured questionnaire. RESULTS: The estimated lifetime prevalence rate of major depressive disorder was 26.6 percent; 6.4 percent of the sample showed evidence of psychotic thinking. Almost one-third reported previous hospitalization for emotional problems, and about one-third reported a suicide attempt. The estimated lifetime prevalence rate of alcohol or drug abuse or dependence was almost 60 percent. CONCLUSIONS: Although mental illness, especially psychosis, and substance abuse may be somewhat less prevalent among homeless persons in lower-density population areas than in large urban areas, they are nevertheless significant problems.  相似文献   
93.
Patients with right lower quadrant (RLQ) pain referred for imaging studies with a clinical diagnosis of appendicitis may have other pathologic conditions mimicking appendicitis. Appropriate diagnostic imaging may establish other specific diagnoses and thereby play a significant role in determining proper medical or surgical treatment. In this pictorial essay, we present a spectrum of imaging findings in patients whose clinical features were suggestive of appendicitis, but the diagnoses of a broad spectrum of other diseases were established with the imaging studies. The differential diagnoses of diseases mimicking appendicitis are reviewed.  相似文献   
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Celiac disease is characterized by small intestinal damage with loss of absorptive villi and hyperplasia of the crypts, typically leading to malabsorption. In addition to nutrient deficiencies, prolonged celiac disease is associated with an increased risk for malignancy, especially intestinal T-cell lymphoma. Celiac disease is precipitated by ingestion of the protein gliadin, a component of wheat gluten, and usually resolves on its withdrawal. Gliadin initiates mucosal damage which involves an immunological process in individuals with a genetic predisposition. However, the mechanism responsible for the small intestinal damage characteristic of celiac disease is still under debate. Small intestinal biopsy with the demonstration of a flat mucosa which is reversed on a gluten-free diet is considered the main approach for diagnosis of classical celiac disease. In addition, IgA antibodies against gliadin and endomysium, a structure of the smooth muscle connective tissue, are valuable tools for the detection of patients with celiac disease and for therapy control. Incidence rates of childhood celiac disease range from 1:300 in Western Ireland to 1:4700 in other European countries, and subclinical cases detected by serological screening revealed prevalences of 3.3 and 4 per 1000 in Italy and the USA, respectively. IgA antibodies to endomysium are particularly specific indicators of celiac disease, suggesting that this structure contains one or more target autoantigens that play a role in the pathogenesis of the disease. However, the identification of the endomysial autoantigen(s) has remained elusive. We identified tissue transglutaminase as the unknown endomysial autoantigen. Interestingly, gliadin is a preferred substrate for this enzyme, giving rise to novel antigenic epitopes.  相似文献   
95.
Solid state fermentation (SSF) represents a technological alternative for processing a great variety of legumes and/or cereals to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. The objectives of this work were (1) to determine the best combination of SSF process variables (fermentation temperature FT/fermentation time Ft) for producing chickpea tempeh flour and (2) to characterise the physicochemical and nutritional properties of the product. Response surface methodology was applied as optimisation technique over three response variables: in vitro protein digestibility (PD), true protein (TP) and water absorption index (WAI). A central composite experimental design with two factors and five levels was used. The process variables FT and Ft had variation levels of 31–36 °C and 48–72 h respectively. Rhizopus oligosporus (1 × 109 spores l?1 in distilled water) was used as starter. Prediction models for response variables were developed as a function of process variables. A conventional graphical method was applied to obtain maximum PD, TP and WAI. Contour plots of each of the response variables were superimposed to obtain a contour plot for observation and selection of the best combination of FT (34.9 °C) and Ft (51.3 h) for producing of chickpea tempeh, which was dried (52 °C, 24 h) and milled to pass through an 80‐US mesh (0.180 mm) screen to obtain optimised chickpea tempeh flour. This flour had higher (p ≤ 0.05) TP (25.7 vs 19.7% dry matter (DM)), total colour difference (30.3 vs 16.7), WAI (4.18 vs 2.15 kg gel kg?1 DM), available lysine (42.7 vs 30.4 g kg?1 protein) and PD (83.2 vs 72.2%) and lower lipid content (2.6 vs 6.1% DM), phytic acid (1.1 vs 10.85 g kg?1 DM), tannins (2.65 vs 21.95 g catechin kg?1 DM) and pH (5.9 vs 6.3) than raw chickpea flour. Copyright © 2004 Society of Chemical Industry  相似文献   
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Forty different sizes and types of square and rectangular stainless steel wires, supplied by five different manufacturers, were tested in torsion. The study simulated the situation occurring when torque is applied to an individual tooth. We used standard brackets with 0.018-inch slot heights, with an interbracket distance of 4 mm. The results show that variation in cross-sectional dimension and edge bevel leads to variable torsional play (third-order clearance). As an example 0.016 x 0.022-inch wires have a mean torsional play of as much as 18.5 degrees, with a range of 16.6 degrees to 20.4 degrees. We have shown that when 0.016 x 0.022-inch wires are used, one must apply from 24.6 degrees to 29.2 degrees of twist to get 20 Nmm of torsional moment. This variation is mostly due to a rather wide range in torsional play. As a result, the prediction by which a predetermined torsional moment can be delivered becomes uncertain. The results show that because the working range in torsion of stainless steel wires is somewhat limited, precise delivery of torsional moment, based on the condition present in the oral cavity, is difficult. Torsional stiffness varies considerable within the various dimensional groups, this being the result of variation in cross-sectional geometry and material properties.  相似文献   
99.
Thirty-seven Nigerian tuberculosis patients and 75 control volunteers were Mantoux-tested with 1 or 5 or 10 tuberculin units of Tween-80 stabilised purified protein derivative (P.P.D.) in order to relate tuberculosis infection to skin reactivity. Serum transferrin and albumin levels determined by radial immunodiffusion technique showed some overlap but test patients tended to have lower values than controls. Skin reaction was not significantly affected by age which varied from 6 to 55 years or the extend of tuberculosis treatment at Mantoux testing. For comparable P.P.D. doses Mantoux readings greater than 9.9mm showed 86.5% sensitivity for tuberculosis but presented low (28%) specificity in contrast to readings greater than 15mm with specificity of 74.7%. Significantly higher proportion of test patients than controls showed skin reaction greater than 9.9mm (p < 0.05) whereas the difference was insignificant at 9mm. With improving nutrition there is need for a large-scale reappraisal of the value of intradermal tuberculin test in diagnosing active tuberculosis in Nigerian reactors.  相似文献   
100.
Forty-seven patients with probable Alzheimer disease (AD) completed a 6-month double-blind study to compare metrifonate with placebo. The Alzheimer Disease Assessment Scale cognitive subscale score of the metrifonate group treated to a 50-70% inhibition of red blood cell acetylcholinesterase activity differed significantly from the placebo group score by 1.8 points (p < 0.03) due to a deterioration in cognitive performance in the placebo group (p < 0.01). Statistically significant deterioration also occurred in the Mini-Mental State Examination scores (p < 0.01) in the placebo-treated group. Adverse effects were uncommon and did not require adjustment of the dose of metrifonate or discontinuation of treatment. These findings extend our previous report of a favorable effect of metrifonate on cognitive symptoms in AD by showing clinical, not only statistical, significance.  相似文献   
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