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1.
Polyglandular autoimmune syndrome (PGAS) type 2 (Schmidt syndrome) is characterized by the association of primary adrenocortical insufficiency with autoimmune thyroid disease, and/or insulin-dependent diabetes mellitus (IDDM). In this report we describe the occurrence of two episodes of post-partum thyroiditis (PPT) after a first and second pregnancy as well the development acutely of adrenal insufficiency after a second pregnancy. A family history of autoimmune thyroid disease and IDDM as well as positive antiadrenal and antithyroid antibodies and HLA typing is evidence for an underlying polyendocrine autoimmune syndrome. This case report provides further evidence that the immune system that is suppressed in pregnancy to tolerate the fetal allograft can rebound post-partum to unmask polyendocrine autoimmune disorders such as adrenalitis and PPT in susceptible women.  相似文献   
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Food shortages often threaten central Tanzania. Sustainable action adapted to local environmental conditions is desperately needed. In the framework of the TransSEC project, two food value chains in the Dodoma region of Tanzania were inspected in order to make propositions for improvement , spanning from soil preparation to product consumption. Therefore, soil mapping approaches were required to obtain rapid and reliable information. This would enable local farmers to participate in the development of upgrading strategies and extensionists to develop recommendations that take local soil conditions into account. In this study, a combination of participatory soil mapping and gamma ray spectrometry-assisted transect mapping was applied to establish local soil maps of two villages in the Dodoma region. Participatory mapping included key informant interviews, group discussions and transect walks. Local farmers indicated reference profiles for local soil types. Their gamma radiation signatures delivered base information for further soil exploration and soil unit delineation in the field. Finally, high resolution satellite images were used to establish the village soil maps. This approach allows capture of the major soil differences within a village territory and reduction of the costs of chemical analyses. Challenges were soil unit separation with gamma ray spectrometry due to erosional redistribution processes at the surface, correct translation of specific terms from local tongues as well as variable individual soil knowledge of local participants. Ultimately, the combination of local soil knowledge with innovative scientific mapping yielded quick results with sufficient spatial resolution for extension work.  相似文献   
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The relationship between Y2O3 content in tetragonal and cubic ZrO2 phases and the shift of the Raman band at ~645/cm was investigated. With increasing Y2O3 content, the 645/cm Raman band position decreases to lower Raman shift values. A fit of x = Y2O3 content in wt% and y = Raman band position in per cm, was found to be valid for low Y2O3‐stabilized t‐ZrO2, t′′‐ZrO2 transition, and fully stabilized c‐ZrO2. Modeling the change in lattice parameters due to the incorporation of Y2O3 in ZrO2 as obtained from Rietveld‐refined XRD data confirms that the peculiar sigmoidal form of the band shift with Y2O3 content is mainly due to a variation of the amount of oxygen vacancies. The resultant method is highly attractive in fields of Y2O3 determination in ZrO2 materials where a fast, spatially resolved, and nondestructive analysis is required.  相似文献   
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An appropriate insulin secretion by pancreatic beta-cells is necessary to maintain glucose homeostasis. A rise in plasma glucose leads to increased metabolism and an elevated cytoplasmic ATP/ADP ratio that finally triggers insulin granule exocytosis. In addition to this triggering pathway, one or more amplifying pathways—activated by amino acids or fatty acid—enhance secretion by promoting insulin granule recruitment to, and priming at, the plasma membrane. The aim of this study was to clarify the impact of the mitochondrial respiratory activity on fatty acid-induced insulin secretion that was assessed by an extracellular flux analyzer. Treatment of isolated mouse islets with glucose (20 mM) increased insulin secretion 18-fold and correlated with ATP-synthesizing respiration. Furthermore, oxygen consumption rate (OCR) significantly increased by 62% in response to glucose, whereas the addition of palmitate resulted only in a minor increase of OCR at both 2.8 mM (11%) and 20 mM glucose (21%). The addition of palmitate showed a pronounced increase of coupling efficiency (CE) at 2.8 mM glucose but no further insulin secretion. However, treatment with palmitate at 20 mM glucose increased insulin secretion about 32-fold accompanied by a small increase in CE. Thus, fatty acid induced respiration has a minor impact on insulin secretion. Our data clearly demonstrate that fatty acids in contrast to glucose play a minor role for respiration-mediated insulin secretion. In the presence of high glucose, fatty acids contribute partially to amplifying pathways of insulin secretion by further increasing mitochondrial activity in the islets of Langerhans.  相似文献   
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Ohne ZusammenfassungTeil einer Dissertationsarbeit vonR. Pires. Techn. Universität München.  相似文献   
8.
Semi-deciduous forest in the Amazon Basin is sensitive to temporal variation in surface water availability that can limit seasonal rates of leaf and canopy gas exchange. We estimated the seasonal dynamics of gross primary production (GPP) over 3 years (2005–2008) using eddy covariance and assessed canopy spectral reflectance using MODIS imagery for a mature tropical semi-deciduous forest located near Sinop, Mato Grosso, Brazil. A light-use efficiency model, known as the Vegetation Photosynthesis Model (VPM), was used to estimate seasonal and inter-annual variations in GPP as a function of the enhanced vegetation index (EVI), the land surface water index (LSWI), and local meteorology. Our results indicate that the standard VPM was incapable of reproducing the seasonal variation in GPP, primarily because the model overestimated dry-season GPP. In the standard model, the scalar function that alters light-use efficiency (εg) as a function of water availability (Wscalar) is calculated as a linear function of the LSWI derived from MODIS; however, the LSWI is negatively correlated with several measures of water availability including precipitation, soil water content, and relative humidity (RH). Thus, during the dry season, when rainfall, soil water content, and RH are low, LSWI, and therefore, Wscalar, are at a seasonal maximum. Using previous research, we derived new functions for Wscalar based on time series of RH and photosynthetic photon flux density (PPFD) that significantly improved the performance of the VPM. Whether these new functions perform equally well in water stressed and unstressed tropical forests needs to be determined, but presumably unstressed ecosystems would have high cloud cover and humidity, which would minimize variations in Wscalar and GPP to spatial and/or temporal variation in water availability.  相似文献   
9.
In 2 experiments (N?=?111 children), a suggestive technique for interviewing child witnesses called "inviting speculation" was examined. Children were presented with atypical actions for common objects in a clown show. One week later, the children were asked to speculate (e.g., "What else could he have done with the knife?") in a between-subjects design on all or none of the items (Experiment 1) and in a within-subjects design on part of the items (Experiment 2), thereby getting highly probable speculations (e.g., "to cut"). After a 3-week delay, the experimenters found more highly probable but not more other false answers for the experimental items (Experiment 2). After a 5–6-month delay, the rate of (unspecified) false answers increased compared with the baseline (Experiments 1 and 2). The short-term effect is explained by a speculation-as-misinformation assumption, whereas the long-term effect is explained by the use of a metastrategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Water-based ionomer dispersions were formed by post-polymerization addition of zirconium species to polymer latices prepared from butyl methacrylate (BMA), butyl acrylate (BA) and acrylic acid (AA) by semicontinuous emulsion polymerization. The mole fraction of AA in the latex particles was kept at 10 mole% in all cases whereas the ratio of BA to BMA was varied. A method was established which allowed zirconium in the form of ammonium zirconium carbonate (AZC) to be successfully introduced into the latices without affecting their colloidal stability. Dynamic light scattering was used to determine average particle size in diluted latices. The structure and properties of cast ionomer films were investigated by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), tensile strength and swelling measurements. Fourier transform infrared spectroscopy (FTIR) was used to investigate the nature of the carboxylate bonding.  相似文献   
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