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Roasting coffee led to a drop in the ochratoxin A (OTA) concentration, as measured by the reference method, especially for dark type roasts. The way the beverage was prepared also affected the OTA content, which could paradoxically be higher than that of the initial roasted coffee. Assays on the thermal stability of pure OTA showed that it ought to be found in larger quantities in roasted coffee. This suggested that OTA was masked by reactions with the substrate during roasting. The absence of OTA in green coffee is therefore the best guarantee of safety.  相似文献   
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Examining the relationship of stress, dietary disinhibition, and blood glucose control in diabetic young women was the goal of this study. 65 diabetic girls and women, ranging in age from 12 to 26 yrs, completed eating behaviors and perceived stress scales during regular clinic visits. Blood glucose control was assessed by concurrent glycosylated hemoglobin measurements. Multiple regression analyses indicated that high levels of perceived stress predicted dietary disinhibition and that within the age range studied, young women were more likely than early adolescent girls to perceive their life as stressful. Contrary to previous findings that failed to show that stress can indirectly affect glucose control by interfering with compliance behaviors, the present work indicated a Stress?×?Dietary Disinhibition interaction in predicting glucose control. Blood glucose control was poorest in those diabetic women who both perceived their lives as stressful and reported medium to high disinhibition. Blood glucose control was unrelated to stress in young women who reported low levels of disinhibition. These results have implications for the development of specific interventions for young diabetic women who perceive their lives as stressful and who may respond to stress by eating. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Coat colors in the chestnut horse, the yellow Labrador retriever, the red fox, and one type of yellow mouse are due to recessive alleles at the extension locus. Similarly, dominant alleles at this locus are often responsible for dark coat colors in mammals, such as the melanic form of the leopard, Panthera pardus. We show here that the murine extension locus encodes the melanocyte-stimulating hormone (MSH) receptor. In mice, the recessive yellow allele (e) results from a frameshift that produces a prematurely terminated, nonfunctioning receptor. The sombre (Eso and Eso-3J) and tobacco darkening (Etob) alleles, which both have dominant melanizing effects, results from point mutations that produce hyperactive MSH receptors. The Eso-3J receptor is constitutively activated, while the Etob receptor remains hormone responsive and produces a greater activation of its effector, adenylyl cyclase, than does the wild-type allele.  相似文献   
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The ideology of fatherhood, as it is defined in Western, industrialized culture, assumes that fathers are biologically predisposed to be relatively uninvolved in infant care. This article summarizes recent revisions of both primate research and sociobiological theory. These new perspectives on male parenting behavior shift the focus from a narrow emphasis on the genetic relationship between male primates and their offspring to a broader focus that includes multiple social, demographic, and ecological variables. This paradigm underlines the behavioral flexibility, rather than the behavioral fixity, of male parenting behaviors. The relevance of this new theoretical consensus for social policy that could strengthen fathers' relationships with their children is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In order to characterize the role of carnitine during metabolic stress, we prospectively determined carnitine profiles in plasma and urine on admission, days 2, 5, 10 and 15, among 28 critically ill children free of any known conditions associated with secondary carnitine deficiency. More than 25% of plasma and 50% of urinary carnitine measurements were abnormal; 96% (27/28) of patients displayed on at least one occasion an abnormal [< -2 SD or > +2 SD] carnitine value in plasma. Three children had extremely low [< 10 micromol/l] free carnitine (FC) levels in plasma. Plasma esterified and FC levels on admission were not related to the risk of mortality [PRISM score], to muscle lysis [CK values], and to the caloric intake. Levels of FC and esterified carnitine in plasma were unrelated to those measured in urine. Conclusion: Abnormal plasma and urine carnitine measurements are frequently found in critically ill children; the biological significance of these perturbations remains unclear. Caution must be exercised before concluding that an abnormal carnitine value is indicative of an underlying hereditary metabolic disorder in this population.  相似文献   
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DESCRIPTION AND ANALYSIS OF TIMBER DRYING KINETICS   总被引:4,自引:0,他引:4  
In this paper an experimental and semi-analytical technique is described that provides a method of estimating a macroscopic drying kinetics curve and internal moisture content profiles is described. Moisture gradients and the time evolution of these gradients are analysed as a function of the air drying parameters (dry-bulb, wet-bulb temperature and the velocity) and the product parameters (thickness and density). The material used as an illustration is a maritime-pine-wood.  相似文献   
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