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Postprandial hyperglycemia in diabetic patients can be modified by delaying the digestion and/or absorption of dietary carbohydrates. We have studied an orally active α-glucosidase inhibitor, Bay 1099, in normal volunteers to determine whether these inhibitors can decrease postprandial rises in serum glucose without causing gastrointestinal symptoms or significant fecal caloric wastage. Six subjects were given 25, 50, or 100 mg of Bay 1099 or placebo before meals for 1 week, each with a 1-week washout period. Fasting and postprandial concentrations of glucose, insulin, glucagon, enteroglucagon, and gastrointestinal inhibitory peptide (GIP) were measured after the first and last dose of Bay 1099, and the fecal excretions of protein, fat, fiber, and total calories were measured on the last three days of each diet. The passage of unabsorbed carbohydrate into the colon was determined by breath hydrogen analysis three times during each study week. Increasing doses of Bay 1099 were found to decrease the postprandial rise in serum glucose concentration, delay the time to peak insulin concentration, and decrease the output of GIP after the meal. No adaptation was apparent after 1 week of therapy. A dose of inhibitor (50 mg tid), which greatly improves postprandial glucose and hormone output in diabetes, was associated with minimal symptoms and no excess fecal caloric losses. Thus, glucosidase inhibitors such as Bay 1099 may be useful in the management of patients with carbohydrate intolerance.  相似文献   
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The antigenically variant major surface protein 2 (MSP2) of Anaplasma marginale is expressed from a 3.5-kb operon that contains, in a 5'-to-3' direction, four open reading frames, opag3, opag2, opag1, and msp2. This operon structure was shown to be conserved among genotypically and phenotypically distinct A. marginale, A. ovis, and A. centrale strains. The individual OpAG amino acid sequences are highly conserved among A. marginale strains, with identities ranging from 95 to 99%. OpAG2 and OpAG3 were expressed by all examined A. marginale strains during the acute rickettsemia in the mammalian host and, like MSP2, localize to the bacterial surface. OpAG2 and OpAG3 were also expressed in an infected Ixodes scapularis tick cell line. In contrast, the same A. marginale strains expressed only OpAG2 in two different Dermacentor spp. during transmission feeding. OpAG1 expression was not detected in the infected mammalian host, the infected tick cell line, or within infected Dermacentor ticks. The differential expression of outer membrane proteins from within an operon is a novel finding in tick-transmitted bacteria, and the regulation of expression may be broadly applicable to understanding how the pathogen adapts to the mammalian host-tick vector transition.  相似文献   
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Typing and in vitro cultivation of rotavirus-positive human stool samples stored unintentionally at ambient tropical temperatures for 2 1/2 months showed that rotavirus is stable and may still be infectious in vitro. This indicates that stool specimen collection for rotavirus studies can be performed in areas and settings where reliable cold storage is not available. The retained infectivity of rotavirus particles underscores the need for safe systems for disposal of feces, in particular in developing countries where rotavirus is a major cause of childhood mortality.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Als ?Generation Y“ werden jüngere Erwachsene bezeichnet, die im ungefähren Zeitraum von...  相似文献   
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Human parechoviruses (HPeVs) often cause severe illness among young children. National surveillance with routine testing of all cerebrospinal fluid, fecal, and tissue samples was conducted during January 2009–December 2012 in all counties in Denmark (6,817 samples from 4,804 children were screened for HPeV). We detected HPeV RNA in 202 (3.0%) specimens from 149 persons. Young infants were at highest risk for HPeV, and 9 (6%) of the HPeV-infected children died, probably of their HPeV illness. HPeV3 was the most common genotype identified, and 5 closely related clades of HPeV3 circulated in Denmark throughout the study period. Our study adds perspective on the prevalence and clinical and molecular virologic characteristics of HPeV infection.  相似文献   
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The tumor stroma is no longer seen solely as physical support for mutated epithelial cells but as an important modulator and even a driver of tumorigenicity. Within the tumor stromal milieu, heterogeneous populations of fibroblast-like cells, collectively termed carcinoma-associated fibroblasts (CAFs), are key players in the multicellular, stromal-dependent alterations that contribute to malignant initiation and progression. This review focuses on novel insights into the contributions of CAFs to disease progression, emergent events leading to the generation of CAFs, identification of CAF-specific biomarkers predictive of disease outcome, and recent therapeutic approaches aimed at blunting or reverting detrimental protumorigenic phenotypes associated with CAFs.  相似文献   
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