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941.
I. PAPA R.G. TAYLOR C. ASTIER F. VENTRE M.C. LEBART C. ROUSTAN A. OUALI Y. BENYAMIN 《Journal of food science》1997,62(5):917-921
Using specific dystrophin antibodies directed against a conserved C-terminal sequence, we demonstrated that dystrophin of fish white muscle was quickly degraded by 50% within 24h and by 100% within 2 days, in parallel with titin cleavage and alpha-actinin release from Z-disks. These changes were accompanied by sarcolemma detachment from the myofibers in costameres (the structures containing dystrophin) and Z-disks weakening. For muscle stored during 2 to 6 mo before thawing, total dystrophin disappearance was observed at 4°C in <8h. Dystrophin may serve as a marker for stored fish to evaluate post mortem changes or detect a thawing-freezing process. 相似文献
942.
Development of Intrinsic Fluorescent Multispectral Imagery Specific for Fat, Connective Tissue, and Myofibers in Meat 总被引:1,自引:0,他引:1
P. O. Skjervold R. G. Taylor J. P. Wold P. Berge S. Abouelkaram J. Culioli É. Dufour 《Journal of food science》2003,68(4):1161-1168
ABSTRACT: Intrinsic fluorescent properties of muscle tissue were evaluated in order to characterize the different structural components of meat. The combinations of excitation and emission wavelengths showing the best ability to distinguish the 3 components were 290/332 nm for myofiber, 322/440 (or 322/405) nm for fat, and 380/440 nm for connective tissue. Sample orientation and the mincing of meat samples affected fluorescent amplitudes but not the overall shape of the spectra. These emission spectra of meat components were used to make multispectral images to determine whether the 3 components could be distinguished. The results show that auto fluorescence can be used for selective visualization of fat, fiber, and connective tissue on digitized images of meat. 相似文献
943.
Back Cover: The Integrin Ligand c(RGDf(NMe)Nal) Reduces Neointimal Hyperplasia in a Polymer‐Free Drug‐Eluting Stent System (ChemMedChem 7/2014) 下载免费PDF全文
944.
Xiao‐Dong Zhang Zhentao Luo Jie Chen Hao Wang Sha‐Sha Song Xiu Shen Wei Long Yuan‐Ming Sun Saijun Fan Kaiyuan Zheng David Tai Leong Jianping Xie 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(14):1683-1690
Ultrasmall gold nanoclusters (Au NCs) show great potential in biomedical applications. Long‐term biodistribution, retention, toxicity, and pharmacokinetics profiles are pre‐requisites in their potential clinical applications. Here, the biodistribution, clearance, and toxicity of one widely used Au NC species—glutathione‐protected Au NCs or GSH‐Au NCs—are systematically investigated over a relatively long period of 90 days in mice. Most of the Au NCs are cleared at 30 days post injection (p.i.) with a major accumulation in liver and kidney. However, it is surprising that an abnormal increase of the Au amount in the heart, liver, spleen, lung, and testis is observed at 60 and 90 days p.i., indicating that the injected Au NCs form a V‐shaped time‐dependent distribution profile in various organs. Further investigations reveal that Au NCs are steadily accumulating in the muscle in the first 30 days p.i., and the as‐stored Au NCs gradually release into the blood in 30–90 days p.i., which induces a re‐distribution and re‐accumulation of Au NCs in all blood‐rich organs. Further hematology and biochemistry studies show that the re‐accumulation of Au NCs still causes some liver toxicity at 30 days p.i. The muscle storage and subsequent release may give rise to the potential accumulation and toxicity risk of functional nanomaterials over long periods of time. 相似文献
945.
Yanen Guo Xiaoyin Xu Yuanyuan Wang Zhong Yang Yaming Wang Shunren Xia 《Microscopy research and technique》2015,78(6):508-518
We developed a computational approach to detect and segment cytoplasm in microscopic images of skeletal muscle fibers. The computational approach provides computer‐aided analysis of cytoplasm objects in muscle fiber images to facilitate biomedical research. Cytoplasm in muscle fibers plays an important role in maintaining the functioning and health of muscular tissues. Therefore, cytoplasm is often used as a marker in broad applications of musculoskeletal research, including our search on treatment of muscular disorders such as Duchenne muscular dystrophy, a disease that has no available treatment. However, it is often challenging to analyze cytoplasm and quantify it given the large number of images typically generated in experiments and the large number of muscle fibers contained in each image. Manual analysis is not only time consuming but also prone to human errors. In this work we developed a computational approach to detect and segment the longitudinal sections of cytoplasm based on a modified graph cuts technique and iterative splitting method to extract cytoplasm objects from the background. First, cytoplasm objects are extracted from the background using the modified graph cuts technique which is designed to optimize an energy function. Second, an iterative splitting method is designed to separate the touching or adjacent cytoplasm objects from the results of graph cuts. We tested the computational approach on real data from in vitro experiments and found that it can achieve satisfactory performance in terms of precision and recall rates. Microsc. Res. Tech. 78:508–518, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
946.
Jin-wu Kang Hao-long Shangguan Fan Peng Jing-ying Xu Cheng-yang Deng Yong-yi Hu Ji-hao Yi Tao Huang Long-jiang Zhang Wei-min Mao 《中国铸造》2021,18(1):18-28
The cooling control of the melt during the casting process is of great significance. A comprehensive closed-loop cooling control of castings by adopting a skeletal sand mold design was proposed. The skeletal sand mold consisting of an adaptive shell, functional cavities and a support was designed and created based on the finite difference meshes of a casting. It was applied to a round wall test casting. Two kinds of skeletal sand molds, one with lattice support and the other with enforcing ribs for this casting were designed and printed out by the 3 D printing(3 DP) method. Aluminum alloy A356 was cast by using these two sand molds. The first mold was cooled by natural convection, the other one by water spray cooling. Two sound castings were obtained. The sand mold temperature, cooling curves, microstructures, mechanical properties, residual stress and deformation were measured, compared and discussed. Water spray cooling hastened the cooling rate by 62%, increased the content of Mg and Cu in the α-Al matrix, improved the mechanical properties, and altered the surface residual stress state. 相似文献
947.
目的:探讨提上睑肌缩短法治疗重度上睑下垂的可行性及疗效,为临床合理治疗提供依据。方法将2011年2月至2012年3月来南昌大学第一附属医院接受手术的26例(32只眼)严重上睑下垂患者,按照不同手术方式分为:提上睑肌缩短术组16例,额肌瓣悬吊术组10例。随访1年,比较提上睑肌缩短术与公认的额肌瓣悬吊术治疗重度上睑下垂的疗效。结果提上睑肌缩短术组术后2只眼欠矫,1只眼过矫,额肌瓣悬吊术组术后1只眼欠矫,1只眼过矫。其余随访1年上睑下垂均得到恢复,无睑内外翻、穹窿结膜脱垂等并发症,且外形美观。2组治愈率分别为85.0%、83.3%,差异无统计学意义(P>0.05)。结论提上睑肌缩短法治疗严重上睑下垂,在矫正眼睑生理功能和改善外观上均达到满意的效果。 相似文献
948.
949.
气动肌肉执行器重量轻、柔性好,被广泛应用于工业与研究领域。然而,用于驱动该执行器的气动设备使系统的尺寸过于庞大,为解决此问题,提出利用氟碳化合物气/液相变时膨胀做功来驱动气动肌肉执行器,选用金属陶瓷加热器加热氟碳化合物,使用PI控制器控制执行器的内部压力,制作拮抗驱动装置改善执行器作用力的动态特性。结果表明:气/液相变气动肌肉执行器内部产生的压力可以较好地跟踪参考输入信号;与空气驱动方式相比,采用气/液相变驱动时执行器的收缩率呈等值减小趋势;拮抗驱动装置能够改善气/液相变气动肌肉执行器作用力消失过程中的动力学特性。 相似文献
950.
Muscle damage can reduces the biological functions and lead to ultimately a disease state. For the reason, it is important to accurately check the state of an injury such as atrophy, and it is required to identify the state of fibers constituting the muscle. This study describes a novel method of analyzing single muscle fibers with injury conditions in three‐dimensions. The muscle fibers of the mice were visualized using phase‐contrast X‐ray projection the microstructure. In additions, it was possible to confirm the status by quantitatively analyzing the injury severity of muscle fibers. Significantly, the muscle conditions of multiple individuals were individually determined. This study could contributes to areas where it is very important to identify microdetailed and quantitative changes of state, such as new drug development. 相似文献