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991.
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994.
为了探讨 b FGF复合膜对自体不同神经桥接物作用的影响。在兔的缺损神经桥接处 ,分别置入被 b FGF复合膜包裹的自体肌桥或自体神经桥。术后 1 80 d,切取神经桥接部位 ,常规制成光、电镜标本 ,进行镜下观察、图象分析测定和统计学处理。结果表明 :自体神经桥组再生的有髓神经纤维的数量及平均直径均小于自体肌桥组 ,但两组间再生神经纤维的数量无显著性差异 (P >0 .0 5) ,而平均直径间存在显著性差异 (P <0 .0 5)。由此可见 ,在创伤局部自体肌桥缝接神经处应用含 b FGF的复合膜 ,不仅对缺损神经的再生有明显的促进作用 ,而且其效果(特别是再生神经纤维发育程度方面 )明显好于自体神经桥接组 相似文献
995.
Takanori NISHIMURA Ayaka TANEICHI Jun-ichi WAKAMATSU Akihito HATTORI 《Animal Science Journal》2003,74(5):399-405
The effect of skeletal muscle decorin on collagen fibrillogenesis was investigated, in order to provide background for understanding the functions of decorin in skeletal muscle. The self‐assembly of type I and III collagen with the addition of decorin or the core protein of decorin from bovine neonatal skeletal muscle was monitored using a spectrophotmeter. Time course changes in the absorbance of collagen solutions showed typical sigmoidal curves composed of three phases. The time of the initial phase was not different between the collagen solution with decorin and that without decorin. The increase rate of the absorbance in the second phase decreased with concentration of decorin added in collagen solutions. Similar effects on fibrillogenesis of type I and III collagens were observed when the core protein of decorin was added in collagen solutions. These results suggest that regulation of collagen fibrillogenesis by decorin depends on its core protein. The networks of reconstructed collagen fibrils with decorin were looser than those without decorin. Bovine skeletal muscle decorin could participate in the regulation of collagen fibrillogenesis and in the arrangement of collagen fibrils in the intramuscular connective tissue. 相似文献
996.
997.
超高压处理对绵羊肉嫩化机理的研究 总被引:14,自引:2,他引:14
实验研究了超高压处理条件下绵羊肌肉感官特性、显微结构、钙激活酶(Calpains)粗酶活性和剪切力值的变化,并探讨了超高压处理对绵羊肌肉的嫩化机理。超高压处理后绵羊肌肉的感官特性发生变化,随处理压力升高,绵羊肌肉颜色变淡,出现轻微的类似蒸煮的成熟风味。在压力为400 MPa,保压时间为10 min的处理条件下,绵羊肌肉显微组织结构变化明显:肌节收缩,肌原纤维的Z线断裂,M线降解,I带变白。当压力水平在100~400 MPa范围变动时,随压力升高,Calpains粗酶活性显著下降(P<0.01);当压力达到400 MPa时,Calpains粗酶活性几乎失活。超高压处理后绵羊肉的剪切力值显著下降(P<0.05)。实验结果表明,超高压处理促进了绵羊肉的嫩化。 相似文献
998.
Cesar H E C Poli Kara J Thornton-Kurth Jerrad F Legako Carolina Bremm Viviane S Hampel Jeffrey Hall Ignacio R Ipharraguerre Juan J Villalba 《Journal of animal science》2021,99(1)
Plant extracts have been widely used in animal production systems due to the benefits promoted by their bioactive components, mainly through their antioxidant effects and positive effects on animal growth, health, and meat quality. We determined whether bioactive compounds (BC) from grape (Vitis vinifera), olive (Olea europaea), and pomegranate (Punica granatum) have beneficial effects on lamb growth while controlling gastrointestinal parasitism and reducing skeletal lipid peroxidation in muscle. Fourteen lambs (4 to 5 mo of age) were housed in individual pens and assigned to two treatment groups (seven animals/group), where they received: 1) a basal diet of beet pulp:soybean meal (90:10) (CONTROL) and 2) the same diet, but containing 0.3% of BC extracted from grape, olive, and pomegranate (BNP). After 21 d of consuming their respective rations (period 1), all lambs were dosed with 10,000 L3 stage larvae of Haemonchus contortus. Intake, production, and physiological parameters were determined before infection (period 1), after oral dosage with L3 (period 2), and during early (period 3) and later (period 4) developmental stages of infection. Groups of animals did not differ in their ration intake or average daily gain, either before or after the infection, or in their parasitic burdens estimated through fecal egg counts (P > 0.05). Lambs under BNP showed greater feed efficiency before infection (P < 0.001), but the pattern reversed after infection. In addition, the inclusion of plant bioactives to the diet did not have an effect (P > 0.05) on blood or lipid peroxidation in muscle or on hemogram, serum concentration of haptoglobin, and immunoglobulin E. These results could be explained by low dietary doses and constrained absorption or ruminal inactivation of these compounds. Changes in feed efficiencies suggest a negative interaction between BC in the diet and parasitism, which warrants further research. 相似文献
999.
Like humans, many companion animals experience a gradual decline in skeletal muscle mass and function during later years of life. This process, analogous to sarcopenia in humans, increases risk for morbidity and mortality. Periods of reduced activity due to injury or illness, followed by an incomplete recovery, can accelerate the loss of muscle mass and function. Emerging research from human studies suggests that moderate amounts of high-quality protein may attenuate the loss of muscle, while preventing accumulation of fat during periods of disuse. Whey protein is a consumer-friendly and readily available source of high-quality protein. It supports skeletal muscle maintenance during normal aging and may also provide anabolic support during periods of illness, injury, and recovery. Ongoing research efforts continue to refine our understanding of how protein quality, quantity, and meal timing can be optimized to support retention of muscle mass and function during aging. Priority research areas include supplementation with high-quality protein during illness/injury to stimulate anabolism by targeting molecular mechanisms that regulate skeletal muscle metabolism. 相似文献