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141.
A women aged 36 with a positive family anamnesis for autoimmune endocrine diseases and a history of thyroid diseases, developed major complaints of general malaise, orthostatic hypotension and loss of appetite after the start of a treatment with levothyroxin because of (sub)clinical hypothyroidism. She was found to suffer from primary adrenocortical insufficiency masked by excessive use of liquorice and a lowered metabolism, but which via the suppletion with thyroid hormone had led to an addisonian crisis.  相似文献   
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143.
Rutile single crystals were implanted at room temperature with fluences of 5 × 1015 Er+/cm2 ions with 150 keV energy. Rutherford backscattering/channeling along the 0 0 1 axis reveals complete amorphization of the implanted region. Photoluminescence reveals the presence of an optical centre close to the intra-ionic emission of Er3+ in the as-implanted samples. After annealing at 800 °C in air no changes were observed in the aligned RBS spectrum. On the contrary, annealing in reducing atmosphere (vacuum) induces the epitaxy of the damage layer. These results are unexpected, since for implantations of other ions under the same conditions, epitaxial recrystallization of the damage region occurs at this temperature. On the other hand, photoluminescence studies show the presence of new Er-related optical centres with high thermal stability in the samples annealed under oxidizing conditions. Annealing at 1000 °C in vacuum leads to the complete recrystallization of the damaged region. At this temperature a large fraction of Er segregates to the surface.  相似文献   
144.
Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) by external injection of matrix-assisted laser desorbed and ionized (MALDI) polymers offers good possibilities for characterization of low molecular weight homopolymers (MW range up to 10 kDa). The molecular masses of the molecular weight distribution (MWD) components of underivatized and derivatized (dimethyl, dipropyl, dibutyl and diacetyl) polyethylene glycol (PEG) 1000 and 4000 were measured by MALDI-FTICR-MS. These measurements have been performed using a commercial FTICR spectrometer with a home-built external ion source. MALDI of the samples with a 2,5-dihydroxybenzoic acid matrix in a 1000:1 matrix-to-analyte molar ratio produces sodiated molecules in a sufficient yield to trap the ions in the ICR cell. The masses of the molecular weight distribution of PEG components were measured in broad-band mode with a mass accuracy of < 5 ppm in the mass range around 1000 u and within 40 ppm accuracy around 4000 u. From these measurements, the endgroup mass of the polymer was determined by correlation of the measured component mass with the degree of polymerization. The masses of the PEG endgroups have been determined within a deviation of 3-10 millimass units for the PEG1000 derivatives and 10-100 millimass units for the PEG4000 derivatives, thus confirming the identity of the distal parts of the model compounds.  相似文献   
145.
Although beef tallow (BT) has been considered a hard low-trans fat convenient to be used in several bakery applications, it has some undesirable characteristics like fatty acid composition, crystallization behavior, graininess formation and poor plastic range. This work studied the modification of BT by blending at different percentages with high oleic sunflower oil (HOSFO) followed by the enzyme-catalyzed interesterification of the blends. The reduction in the solid fat content achieved by the simple blending was enhanced by the interesterification process, as a result of the increase in the concentration of the diunsaturated monosaturated type triacylglycerols. Interesterification strongly impacted too on the crystallization behavior of the blends, since products showed more homogeneous and regular crystals than the starting mixture. Results show that lipase catalyzed interesterification of BT with HOSFO offers a useful tool for the design of fats with adjustable physicochemical properties, improved with respect to that of the starting fats.  相似文献   
146.
There is a pandemic of obesity and associated chronic diseases. Dietary calcium and vitamin D have many extra-skeletal roles in human health. In this review we have summarized the current understanding of their influence on human energy balance by examining the epidemiological, clinical, animal, cellular and molecular evidence. We opine that while calcium and vitamin D are functional nutrients in the battle against obesity, there is a need for prospective human trials to tilt the balance of evidence in favour of these nutrients.  相似文献   
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148.
PURPOSE: We compare the efficacy of percutaneous nephrostomy with retrograde ureteral catheterization for renal drainage in cases of obstruction and infection associated with ureteral calculi. MATERIALS AND METHODS: We randomized 42 consecutive patients presenting with obstructing ureteral calculi and clinical signs of infection (temperature greater than 38 C and/or white blood count greater than 17,000/mm.3) to drainage with percutaneous nephrostomy or retrograde ureteral catheterization. Preoperative patient and stone characteristics, procedural parameters, clinical outcomes and costs were assessed for each group. RESULTS: Urine cultures obtained at drainage were positive in 62.9% of percutaneous nephrostomy and 19.1% of retrograde ureteral catheterization patients. There was no significant difference in the time to treatment between the 2 groups. Procedural and fluoroscopy times were significantly shorter in the retrograde ureteral catheterization (32.7 and 5.1 minutes, respectively) compared with the percutaneous nephrostomy (49.2 and 7.7 minutes, respectively) group. One treatment failure occurred in the percutaneous nephrostomy group, which was successfully salvaged with retrograde ureteral catheterization. Time to normal temperature was 2.3 days in the percutaneous nephrostomy and 2.6 in the retrograde ureteral catheterization group, and time to normal white blood count was 2 days in the percutaneous nephrostomy and 1.7 days in the retrograde ureteral catheterization group (p not significant). Length of stay was 4.5 days in the percutaneous nephrostomy group compared with 3.2 days in the retrograde ureteral catheterization group (p not significant). Cost analysis revealed that retrograde ureteral catheterization was twice as costly as percutaneous nephrostomy. CONCLUSIONS: Retrograde ureteral catheterization and percutaneous nephrostomy effectively relieve obstruction and infection due to ureteral calculi. Neither modality demonstrated superiority in promoting a more rapid recovery after drainage. Percutaneous nephrostomy is less costly than retrograde ureteral catheterization. The decision of which mode of drainage to use may be based on logistical factors, surgeon preference and stone characteristics.  相似文献   
149.
为了使得计算机能自动生成表达力丰富的三维场景的艺术绘制,提出了一种基于Shader的多重绘制模型,并采用了多重绘制的协调、参数空间的纹理铺陈、基于色调的表现控制等技术来进行模拟.引入多重绘制可以同时采用对象空间的绘制和图像空间的绘制,通过纹理铺陈描述语言Shader,用户可以定义自己的纹理和笔划来表现三维和二维场景.不同于传统的Shader,基于Shader的多重绘制模型采用光亮度、材质颜色等作为输入,由用户自行决定绘制结果的输入.这一用户可定制性的引入大大增强了艺术绘制的表现能力.该模型已经在一个建筑设计系统中得到实现,以钢笔画为表现媒介的图例表明该模型模拟效果令人满意.  相似文献   
150.
In this study, the feasibility of using a biohydrometallurgical technique for selective metals recovery from electronic waste (e‐waste) by bacterial bioleaching was investigated. Acidithiobacillus was identified in coal mining acid mine drainage (AMD). The microorganism was studied using specific sequencing of a 16s rDNA fragment. The potential for the dissolution of copper from waste printed wire boards (PWBs) using the isolated Acidithiobacillus ferrooxidans (A. ferroxidans) was evaluated. The bioleaching experiments were performed in an orbital shaker at 30 °C and 170 rpm, with 10 % (v/v) inoculum and a pulp density of 30 g/L. The copper concentration was determined by energy dispersive x‐ray fluorescence (XRF). The result shows that copper recovery from PWBs using our A. ferrooxidans strain was 95 % after 8 days, which showed the feasibility of this process.  相似文献   
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