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191.
The aim of this study was to use whole-body magnetic resonance imaging (MRI) together with biochemical and anthropometric measurements to study the influence of regular moderate exercise with no dietary intervention on adipose tissue distribution in nonobese healthy women. We found significant decreases in both total (28.86±2.24 vs. 27.00±2.27 liters, P<0.05) and regional fat depots (visceral fat: 1.68±0.21 vs. 1.26±0.18 liters, P<0.01) using whole-body MRI despite no significant change in body weight, body mass index, or the waist-to-hip ratio. Interestingly, no changes in body fat content were found using anthropometry or impedance. There was a significant increase in high density lipoprotein cholesterol (1.58 ±0.06 vs. 1.66±0.08 mmol/L P<0.02) following exercise although there were no changes in other blood lipids such as triglycerides. In summary, moderate aerobic exercise over a period of 6 mon resulted in a preferential loss in visceral fat in nonobese healthy women, and this may help to explain some of the health benefits associated with regular and moderate physical activity.  相似文献   
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We describe a new light transport model, which was applied to three-dimensional lifetime imaging of F?rster resonance energy transfer in mice in vivo. The model is an approximation to the radiative transfer equation and combines light diffusion and ray optics. This approximation is well adopted to wide-field time-gated intensity-based data acquisition. Reconstructed image data are presented and compared with results obtained by using the telegraph equation approximation. The new approach provides improved recovery of absorption and scattering parameters while returning similar values for the fluorescence parameters.  相似文献   
194.
Up to 40% of advance lung, melanoma and breast cancer patients suffer from brain metastases (BM) with increasing incidence. Here, we assessed whether circulating tumor cells (CTCs) in peripheral blood can serve as a disease surrogate, focusing on CD44 and CD74 expression as prognostic markers for BM. We show that a size-based microfluidic approach in combination with a semi-automated cell recognition system are well suited for CTC detection in BM patients and allow further characterization of tumor cells potentially derived from BM. CTCs were found in 50% (7/14) of breast cancer, 50% (9/18) of non-small cell lung cancer (NSCLC) and 36% (4/11) of melanoma patients. The next-generation sequencing (NGS) analysis of nine single CTCs from one breast cancer patient revealed three different CNV profile groups as well as a resistance causing ERS1 mutation. CD44 and CD74 were expressed on most CTCs and their expression was strongly correlated, whereas matched breast cancer BM tissues were much less frequently expressing CD44 and CD74 (negative in 46% and 54%, respectively). Thus, plasticity of CD44 and CD74 expression during trafficking of CTCs in the circulation might be the result of adaptation strategies.  相似文献   
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A scaled-up dielectric barrier discharge (DBD) reactor has been developed and demonstrated for the production of hydrogen from steam methane reforming (SMR) by catalytic nonthermal plasma (CNTP) technology. Compared to SMR, CNTP offers conversion at ambient pressure (101.325 kPa), low temperature with better efficiency, making it suitable for distributed hydrogen production with small footprint. There have been several lab-scale DBD reactors reported in the literature. Dimension of the scaled-up DBD reactor is about six times the lab-scale version and can produce 0.9 kg H2/day. The scale-up is, however, nonlinear; several technical innovations were required including spray nozzle for homogeneous introduction of steam, perforated tube central electrodes for generation of homogeneous plasma. Conversion efficiency of the scaled-up DBD reactor is 70–80% at 550°C and 500 W. A continuous run of 8 hr was demonstrated with typical product gas composition of 69% H2, 6% CO2, 15% CO, 10% CH4.  相似文献   
197.
M‐50 and carburized Pyrowear 675® (Carpenter Technology, Reading PA, USA) steel coupons deposited with commercially available physical vapour deposited TiN, TiCN, TiAlCN, TiCrCN/TiB4C multilayer, electroless Ni (E‐Ni) TiN and E‐Ni TiCN coatings were immersed in a branched perfluoropolyalkylether (PFPAE), Krytox AC® (E.I. du pont de Nemours and Company, Wilmington DE, USA), in an oxidative environment at temperatures ranging from 315 to 360 °C for a duration of 24 hours and compared with uncoated coupons. Coated and uncoated Pyrowear 675® coupons demonstrated superior corrosion resistance compared with coated and uncoated M‐50 respectively. The coatings most resistant to chemical attack in the PFPAE fluid were TiCN, E‐Ni TiN and E‐Ni TiCN. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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