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991.
992.
Frostbite injuries have traditionally been treated with expectant observation. With the exception of early blister aspiration tissues are allowed to demarcate before definitive debridement is accomplished. Triple-phase bone scanning has been used to define the extent of fatally damaged tissues in an attempt to allow for early debridement and wound closure. We suggest extending this technology to assess injury and direct debridement in patients for whom early aggressive salvage attempts are indicated. We present two cases in which triple-phase scanning was used to direct early debridement for aggressive limb salvage with flap reconstruction. Bone, ligament, tendon, and nerve were preserved and covered with vascularized tissue before the onset of frank necrosis. Postoperative scans reveal revascularization of these tissues. An algorithm incorporating triple-phase scanning for the evaluation and treatment of frostbite is presented.  相似文献   
993.
994.
Insulin-like growth factor I (IGF-I) is a potent mitogen for many tumor cell lines, and IGF-I receptors are overexpressed in many tumors. Specific IGF-binding proteins (IGFBPs) modulate the interaction of IGF and its receptors. Consequently, radiolabeled IGF-I has been considered for tumor imaging. In the present study, we investigated the biodistribution of 125I-labeled des(1-3)IGF-I, a truncated analogue of IGF-I, in tumor-bearing nude mice. Additional studies included its catabolism by tumor cells in vitro and its binding to serum IGFBPs in vivo in nude mice. We also compared groups that were and were not injected with unlabeled peptide analogue. Our data showed that 125I-labeled des(1-3)IGF-I catabolized very fast, with a rapid appearance of nonprecipitable iodine, when incubated at 37 degrees C, but it was not catabolized at 4 degrees C incubation. 125I-labeled des(1-3)IGF-I was bound to serum-binding proteins, mainly in a complex with a molecular weight of M(r) 150,000. The uptake of radioactivity in normal tissues decreased quickly with time, particularly in the kidneys. In mice receiving higher doses of des(1-3)IGF-I, the radioactivity in all normal tissues was lower than in the mice with no carrier-added des(1-3)IGF-I, except in the stomach and spleen. These data suggest that 125I-labeled des(1-3)IGF-I is rapidly internalized after binding to the IGF receptor and is rapidly catabolized with release of breakdown products. Lower specific activity of 125I-labeled des(1-3)IGF-I resulted in altered biodistribution, including faster blood clearance and higher tumor uptake, by decreasing the formation of complexes with IGFBPs.  相似文献   
995.
996.
Paper summarized a concise evaluation of short wounds according to the Red Cross Classification published in Geneva. It is supposed to attract the forensic physician's attention due to informative purpose.  相似文献   
997.
Styrene‐butadiene rubber (SBR) and polybutadiene rubber (BR) were mixed together (75:25 by mass) to produce two SBR/BR blends. The blends were reinforced with a precipitated amorphous white silica nanofiller the surfaces of which were pretreated with bis(3‐triethoxysilylpropyl)‐tetrasulfide (TESPT). TESPT is a sulfur‐bearing bifunctional organosilane that chemically bonds silica to rubber. The rubbers were primarily cured by using sulfur in TESPT and the cure was optimized by adding non‐sulfur donor and sulfur donor accelerators and zinc oxide. The hardness, Young's modulus, modulus at different strain amplitudes, tensile strength, elongation at break, stored energy density at break, tear strength, cyclic fatigue life, heat build‐up, abrasion resistance, glass transition temperature, bound rubber and tan δ of the cured blends were measured. The blend which was cured with the non‐sulfur donor accelerator and zinc oxide had superior tensile strength, elongation at break, stored energy density at break and modulus at different strain amplitudes. It also possessed a lower heat build‐up, a higher abrasion resistance and a higher tan δ at low temperatures to obtain high‐skid resistance and ice and wet‐grip. Optimizing the chemical bonding between the rubber and filler reduced the amount of the chemical curatives by approximately 58% by weight for passenger car tire tread. This helped to improve health and safety at work and reduce damage to the environment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
998.
Ceria (CeO2) aerogels with high surface area and high porosity have been prepared. Ce-methoxyethoxide diluted in excess methoxyethanol was slowly hydrolyzed to yield a gel, which was then supercritically dried in CO2. Both as-synthesized and annealed aerogels were examined by X-ray powder diffraction, infrared spectroscopy, scanning electron microscopy, and BET surface area and pore-size analyses. Thermal analysis of the as-synthesized gel showed it to contain only ∼5 wt% residual organics, which were removed by 300°C under oxygen. The unheated ceria aerogel was crystalline and exhibited a specific surface area of 349 m2/g with average pore diameter of ∼21.2 nm and 90% porosity. Heat treatment led to a reduction of porosity and pore size, as would be expected, but the extremely narrow pore-size distribution of the aerogel was retained.  相似文献   
999.
The use of safety climate measures for needs assessment and interventions has become increasingly popular. However, no research to date has examined whether the meaning and level of safety climate may differ across different groups of interest. This study used multi-group confirmatory factor analyses to investigate the measurement equivalence of a multidimensional safety climate measure across ten construction trade groups (N = 4725). In addition, observed mean differences in safety climate perceptions between trades were examined. Results revealed strong measurement equivalence of the safety climate measure across the construction trade groups. Further, significant mean differences were found between the ten trade groups on all four safety climate scales.  相似文献   
1000.
M. A. Haile  P. G. Ifju 《Strain》2012,48(2):136-142
Abstract: The refraction‐induced image distortion introduces large errors in the deformation measurement of fluid submerged specimens using digital image correlation (DIC). This study provides a review of the nature of the refraction‐induced image distortion, assesses experimental conditions that interact with refraction and proposes an elastic image registration technique to correct the refraction distortion of underwater images. In the elastic image registration technique, control points are selected on reference and refracted images of a template object and locally sensitive transformation functions that overlay the two images are obtained. The transformation functions so obtained are then used to reconstruct undistorted images from underwater images and the former are used as input to a DIC system. The proposed approach has shown to improve the refraction error in the order of 5–8% for typical material test samples undergoing deformation inside a water‐filled glass chamber.  相似文献   
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