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41.
Effects provoked by chronic undernourishment on the fibre type composition and contractility of fast muscles in male and female developing rats 
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下载免费PDF全文 J. Pereyra‐Venegas B. Segura‐Alegría J. C. Guadarrama‐Olmos S. Mariscal‐Tovar S. Quiróz‐González I. Jiménez‐Estrada 《Journal of animal physiology and animal nutrition》2015,99(5):974-986
In this study, we compare the effects of pre‐ and post‐natal food deprivation on the relative proportion of fibre types and contractile responses in the extensor digitorum longus (EDL) muscle of female and male rats at different post‐natal ages. EDL muscles from undernourished male (UM) rats showed a higher proportion of Type IIB than IIA fibres and larger normalized twitch responses (with respect to muscle weight) than those of controls (CM). In contrast, EDL muscles from control (CF) and undernourished female rats (UF) showed no significant differences in their fibre type composition and normalized twitch forces at most of the ages analysed. Our data are indicative that the EDL muscles from undernourished males are more susceptible to the effects exerted by low food income than the EDL muscles from female rats. It is proposed that changes in the reactive oxygen species (ROS) concentration and hormonal factors, due to undernutrition, are involved in the alterations observed in the fibre type composition and force production of EDL muscles in undernourished male rats and that estrogens may have an antioxidant protective role on the undernourished EDL muscles in female rats. 相似文献
42.
采用高技术处理的特种碳纤维编织物，替代实验动物兔膝关节滑膜，将实验动物分期分批剖杀并用扫描电子显微镜对增生的滑膜了观察。 相似文献
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Substitution effect of sea tangle (ST) (Laminaria japonica) with tunic of sea squirt (SS) (Halocynthia roretzi) in diet on growth and carcass composition of juvenile abalone (Haliotis discus,Reeve 1846) 下载免费PDF全文
下载免费PDF全文 B. Jang P.Y. Kim H.S. Kim K.W. Lee H.J. Kim D.G. Choi S.H. Cho B. Min K. Kim H. Han 《Aquaculture Nutrition》2018,24(1):586-593
Substitution effect of sea tangle (ST) with tunic of sea squirt (SS) in diet on growth and carcass composition of juvenile abalone was determined. One thousand four hundred and seventy abalones were distributed into 21 containers. Six formulated diets in triplicate were prepared. A 200 g/kg ST was included into the ST0 diet. The 200, 400, 600, 800 and 1000 g/kg of ST were substituted with the same amount of tunic of SS, referred to as the ST200, ST400, ST600, ST800 and ST1000 diets, respectively. Finally, Undaria was prepared to compare effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone for 16 weeks. Weight gain of abalone fed the ST400 diet was higher than that of abalone fed the ST0, ST600, ST800 and ST1000 diets and Undaria. Weight gain of abalone fed the formulated diets was higher than that of abalone fed the Undaria. The chemical composition of the carcass of abalone was affected by dietary substitution of ST with tunic of SS. In conclusion, ST could be completely substituted with tunic of SS without retardation in performance of abalone. Abalone fed the ST400 diet substituting 400 g/kg ST with tunic of SS achieved the best growth. 相似文献
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Jean-Charles Bénézet Andréa Stanojlovic-Davidovic Anne BergeretLaurent Ferry Alain Crespy 《Industrial Crops and Products》2012,37(1):435-440
Biodegradable foams made from potato starch and natural fibres were obtained by extrusion. The effects of varying origins of these fibres on foam properties were studied, as well the relationships between their properties and the foam microstructure. The addition of fibres increased the expansion index and led to a significant reduction in water adsorption of starch foams, generally improving foam properties. The mechanical properties of the foams were affected by both relative humidity (RH) of storage and foam formulation. In general, as the RH increased, the foam strength decreased. The formulation presenting the best mechanical properties contained 10 wt% hemp fibre and had a maximal resistance of 4.14 MPa and a modulus of 228 MPa, corresponding to a more compact and dense microstructure. 相似文献
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Rocío JaraboMª Concepción Monte Angeles BlancoCarlos Negro Julio Tijero 《Industrial Crops and Products》2012,36(1):14-21
Nowadays, certain components of non-wood annual plants such as corn stalk and industrial hemp core are considered waste materials or used in low value applications; both by-products have a very low cost. On the other hand, given the large quantities of these materials generated worldwide and their renewable character, it is reasonable to explore new routes for their exploitation. The aim of this paper is to study the potential of both corn stalk (Zea Mays L.) and industrial hemp core (Cannabis Sativa L.) fibres as a renewable source of cellulose fibres in the production of fibre-cement. For each source of fibres, a number of chemical cooking treatments were studied. The morphological properties of the fibres were determined using a scanning electron microscope and a fibre and pulp morphological analyser. Pulp refining was carried out in a PFI mill to improve the characteristics of the fibres. In the case of corn fibres, different degrees of refining were applied. The fibre flocculation process was investigated using several polyacrylamides. The process was studied by monitoring the chord size distribution in real time by means of a focused beam reflectance measurement probe.The results indicated that both pulps can be used for the production of fibre-cement, having the two types of pulp morphological similarities with the pine fibres currently used.Through the flocculation process it was concluded the floc size depends on the length of the fibres. 相似文献
46.
本文根据木材的解剖构造提出木棒在横向振动中的“纤维束”模型,利用这模型可在清晰的物理图象中建立振动方程,然后求出横向振动的共振频率公式。 相似文献
47.
比较了茶叶租纤维定量分析的常规实验塞法和“托卡”纤维仪法。结果表明,后者具有误差小、精确度好及效率高等优点,并且适用于绿茶、红茶及砖茶等多种茶类,2种方法测定结果的相关系数达0.9481。“托卡”法可以完全替代常规实验室法。 相似文献
48.
An analytical model named fibres bend model (FBM) is presented for the in plane mechanical properties of stitched composite laminates. It is supposed that the primary reason of the effect of the in plane mechanical properties of stitched composite laminates is the misalignment of the fibres as they are forced to spread around the stitches. The geometrical characteristics of the fibres in the stitch unit cells are considered. The elastic relation of stress and strain of the stitched laminates is obtained finally. The in plane tensile strength is calculated in the example of the stitched composite laminates [0/45/0/-45/90/45/0/-45] 2S . The results show that the theoretical predicted values accord well with the experiments. The model is proved to be feasible. 相似文献
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