3-甲基组氨酸三室模型在研究猪骨骼肌蛋白质降解中的应用

3-甲基组氨酸(3MH)主要是动物骨胳肌蛋白分解代谢产物，它不能再用于合成蛋白，因而3MH是研究动物骨胳肌蛋白降解率的一个可行示踪物．将标记的3MH经颈静脉注射，对血液中的同位素丰度进行观测，再根据猪体内3MH代谢特点，构建出猪骨胳肌蛋白降解的三分域模型．本文着重对该模型的的理论基础进行了讨论。     

Alanine and aspartate aminotransferases in normal and denervated skeletal muscle

Summary Activities of alanine and aspartate aminotransferases are maintained during the first 5 weeks of growth, but decrease subsequently in normal chick gastrocnemii. In sciatectomized muscles, a 5-fold elevation in these enzymes reveals increased utilization of amino acid as a compensatory metabolic support during denervation atrophy.     

Muscle proteinase activities during compensatory growth and atrophy

Summary Specific activities of cathepsins B and D, but not H, increased in both the tenotomized gastrocnemius and functionally overloaded soleus muscles, thus correlating with previously reported increases in protein degradation. Subsequent denervation of the overloaded soleus caused an additive increase in proteolysis, suggesting a possible greater lability of proteins in this muscle.     

Embryonic chick muscle produces an FGF-like activity

Normal and pathological formation of blood vessels is of considerable interest both in terms of basic scientific processes and clinical applications. Angiogenic events in the adult are likely to represent persistence of developmental mechanisms, and embryos are therefore a suitable experimental model for these processes. Among embryonic tissues, muscle is particularly appropriate for investigation, since it is highly vascularised from early stages. There are a number of competing explanations of how this process is controlled. Bioassays offer advantages over conventional molecular localisation techniques, in that they reveal the presence of active processed forms of the molecules under study, rather than non-processed forms, or non-translated meassages. Using these techniques, we report here that embryonic chick muscle, taken from the stages at which blood vessels are forming, produces an angiogenic activity on the chick chorioallantoic membrane (CAM), and transforms NR6 cells in soft agar. Basic fibroblast growth factor (bFGF) is shown to be angiogenic on the CAM in the same way, and also transforms NR6 cells (NR6 cells lack functional epidermal growth factor/transforming growth factor-a receptors, and are believed to respond only to bFGF in this way). Anti-bFGF removes the transforming activity of the embryonic muscle. We conclude that this represents evidence that embryonic chick muscle is producing an FGF-like molecule which is capable of acting as an angiogenic agent at the appropriate times in development.     

Intramuscular comparison of myosin isozymes and light chains in rat extensor digitorum longus muscle

Summary Complete muscle cross sections were obtained from the proximal and distal third regions of ten rat extensor digitorum longus muscles. Electrophoretic methods were then used to quantify the various myosin isozymes and light chains in each muscle specimen. The results demonstrated that the relative distribution of the various myosin isozyme and light chain variables do not vary significantly between the two sampling regions.     

气动人工肌肉的模糊小波神经网络控制

针对一种应用于医疗机器人领域的三自由度人工肌肉的非线性特性，结合模糊理论与小波神经网络，提出一种模糊小波神经网络控制器对人工肌肉驱动器进行控制。利用模糊小波神经网络的学习能力，采用梯度法搜寻控制器的最优参数。将采用模糊小波神经网络控制器与采用小波神经网络控制器及模糊神经网络控制器的控制系统仿真结果进行比较。仿真结果说明模糊小波神经网络控制器有效地改善了驱动器的静动态特性，具有更快的训练速度和更好的控制效果，是一种理想的气动人工肌肉控制方法。     

15-KETE对大鼠肺动脉平滑肌细胞上ERK1／2活性的影响

目的从细胞分子水平上研究15-酮基二十碳四烯酸（15-ketoeicosatetretraenoicacid,15-KETE）对大鼠肺动脉平滑肌细胞上ERKl／2的活性的影响。方法通过酶法分离、培养SD大鼠肺动脉平滑肌细胞（pulmonaryarterialsmoothcells,PASMCs）,使用Westernblot技术观察15-KETE对大鼠PASMCs上ERKl／2活性的影响。结果1）10～mol／L15-KETE作用从0．5h到24h与对照组（未加15-KETE）比较,对ERKl／2总量没有明显的影响。2）与对照组比较,15-KETE处理0．5、1．0、2．0、4．0、8．0h明显增强P—ERKl／2（P〈0．05）。3）与对照组比较,10、10^-7和10～mol／L15-KETE明显增强p-ERKl／2（P〈0．05）,随15-KETE浓度增大,p-ERKl／2增多。4）与15-KETE作用比较,ERKI／2抑制剂PD9805920μmol／L、50txmol／L和U01260．1txmol／L、1btmol／L均能抑制15-KETE对ERKl／2的活化（P〈0．05）,并且随着抑制剂浓度增大,抑制作用加强。结论15-KETE对大鼠肺动脉血管平滑肌细胞上的ERKl／2表达没有明显的影响,但能激活肺动脉血管平滑肌细胞ERKI／2．使其磷酸化,并呈时间一剂量依赖关系。ERKl／2通路的特异性抑制剂PD98059、U0126能抑制15-KETE对ERKl／2的磷酸化。     

训练对骨骼肌的影响

骨骼肌作为运动的直接动力来源,是运动员精准完成技术动作的关键。本文从对骨骼肌横截面积的研究、对肌纤维类型和MHC的研究、对mRNA的研究、对蛋白质组的研究等四个方面进行了综述,以期为教练员进行科学的力量训练提供指导。     

西洋参叶二醇组皂苷抑制血管平滑肌细胞增殖及影响原癌基因表达的研究

观察PQDS对VSMC增殖及原癌基因c-myc的mRNA表达的影响,探讨PQDS抑制VSMC的增殖作用及相关机制。方法用组织贴块法培养大鼠胸主动脉VSMC作为研究对象,用AngⅡ诱导VSMC增殖,随机分为：空白对照组、AngⅡ模型组、AngⅡ＋PQDS 25、50、100mg/L不同剂量组。用MTT法、流式细胞术、RT-PCR法观察PQDS对细胞增殖、细胞周期、增殖指数及原癌基因c-myc的mRNA表达的影响。结果PQDS可减低VSMC的增殖能力,将增殖的VSMC抑制在G0/G1期,可以下调VSMC中的原癌基因c-myc的mRNA表达。结论PQDS能抑制VSMC增殖,其机制可能与下调原癌基因c-myc的表达有关。