The effects of castration on body composition, adipose tissue cellularity and lipid and carbohydrate metabolism in adult male rats

Gonadal hormones affect body composition, food intake, weight gain and serum lipids in numerous species including man. In this study, mature male Sprague-Dawley rats were castrated or sham-operated at 16 weeks of age. During the 6-week observation period with weekly records of food intake and weight gain, these parameters were significantly lower in the castrated group. The decrease in food intake in this group could not account for the difference in body weight between the groups, indicating a lower feed utilisation in the castrates. At sacrifice accessory reproductive organs, the levator ani muscle, thymus and adrenals were dissected for determination of organ weight and histology, revealing significant reductions in the accessory reproductive organs and levator ani of the castrates. The thymus was significantly heavier in the castrated animals. No differences were found in the adrenals. Two of the sham-operated animals had signs of accidental functional castration. The proportion of body cell mass and total lipid of the carcass was the same in both groups. Significant reductions in adipocyte weights were found in the epididymal depots of the castrated rats. Blood samples taken at sacrifice in pentobarbital anaesthesia were analysed for glucose, insulin, triglycerides, cholesterol, FFA, glycerol and protein. Statistically significant reductions in triglycerides and protein were recorded in the castrated animals without any significant changes in the other parameters studied. The results are discussed with reference to the age of castration and the importance of the reduced food intake in castrated animals.     

Localization of intraorbital foreign bodies

A study was performed utilizing 3 mock eyes of different sizes to determine the precision and accuracy of 3 radiographic methods of localization of intraorbital foreign bodies. The Comberg method was found to be the most precise and accurate, next, the Sweet method, and then the modified spectacle frame method. However, the modified spectacle frame field expedient method of localization yielded a surprisingly high degree of accuracy in 2 of the 3 planes of reference, that is, mediolaterally and superointeriorly. A more accurate field expedient type of device which will permit greater accuracy in localization of intraorbital foreign bodies in the anteroposterior axis is currently under development.     

环境友好催化剂酸性皂土催化1,1-二乙酸酯合成反应的研究

利用对环境友好的酸性皂土做催化剂,糠醛与乙酸酐发生缩合反应合成了1,1-二乙酸酯,产率高达86.6%。实验结果表明,酸性皂土催化该反应具有价廉无污染、选择性高、反应条件温和、反应时间短、后处理简单、易回收、可重复利用等优点。     

接装纸透气度和滤棒吸阻对卷烟烟气细胞毒性的影响

采用中性红细胞毒性试验测试了不同透气度接装纸卷烟和不同吸阻滤棒卷烟烟气冷凝物的细胞毒性,并初步分析了卷烟烟气的细胞毒性指标与CO,NNK,NH3,HCN,B[a]P,巴豆醛和苯酚释放量之间的相关性.结果表明:①随着接装纸透气度的增大,卷烟烟气冷凝物的细胞毒性呈降低趋势;细胞毒性指标与CO,NNK,NH3,HCN,B[a]P,巴豆醛和苯酚的释放量之间具有一定的相关性;②随着滤棒吸阻的增大,卷烟烟气冷凝物的细胞毒性呈降低趋势;细胞毒性指标与NH3,HCN,B[a]P和苯酚的释放量之间具有一定的相关性.     

醋纤和丙纤滤嘴对烟气挥发性、半挥发性成分释放量的影响

分析了聚丙烯(PP)滤嘴卷烟和醋纤(CA)滤嘴卷烟烟气常规成分和挥发性半挥发性成分的释放量.结果表明:①两种滤嘴卷烟的总粒相物、烟碱、焦油和CO释放量相当;②PP滤嘴卷烟大部分挥发性半挥发性成分的释放量都比CA滤嘴卷烟高或者相当,而且PP滤嘴卷烟与CA滤嘴卷烟释放量比值波动较大;③PP滤嘴卷烟烟气中糠醛、糠醇、苯乙醛、吡啶、乙酸、苯酚、对+间甲酚和邻甲酚的释放量远远高于CA滤嘴卷烟.     

大豆肽的营养及其在食品工业中应用安全性探讨

0 引言 大豆是一种重要的蛋白和生物活性肽的潜在资源.大豆的主要贮存蛋白质组分是β-伴大豆球蛋白(β-conglycinin)和大豆球蛋白(glycinin)组成,大豆蛋白质的分子结构复杂,80%的分子量在10万以上,大多数内部分子结构呈反行非有序结构,分子高度压缩、折叠,大豆球蛋白三级结构、四级结构(特别是二硫桥键使其亚基牢固结合)高度结构化形成规则实体,从而使得大豆蛋白质消化吸收率和生物效价远不及牛奶、蛋等动物蛋白质.另外,大豆蛋白质的低pH值时溶解性、高浓度时的高黏度等功能特性也不能完全满足食品加工特别是流体食品的加工的需要.为了进一步提高大豆蛋白质的营养功能,并改善其加工特性,充分发挥大豆蛋白质在维系人体健康方面的重要作用,提高大豆产品的附加值,必须应用现代生物高科技手段,开展大豆蛋白加工与功能研究工作,将大豆蛋白质生物活性肽类释放,发挥生理效能.     

冻干PST脂质体的制备及物理稳定性的研究

用卵磷脂、十八胺、胆固醇为原料,用超声波乳化逆相蒸发制备PST脂质体,并在-65℃冷冻干燥形成固体。测定粒颗粒形态、Zeta电位DSC等,研究其物理稳定性,发现冻干样品性质稳定。     

Contribution of Protein Flexibility to the Foaming Properties of Casein

The effect of biopolymer flexibility on the foaming properties of casein was investigated. Flexibility was altered by: (1) chemical modification (covalent binding of a monosaccharide on the lysyl residues) or (2) pH change. Electron Spin Resonance was used to measure the reorientational frequency of casein residues labeled with nitroxide radicals. High levels of glycosylation induced increased protein flexibility and improved the foaming capacity. Good agreement was observed between higher values of flexibility and improved surface properties near the isoelectric point.     

Electrical transport and thermoelectric properties of AgPb<Subscript>10</Subscript>SbTe<Subscript>12</Subscript> prepared by high pressure method

Thermoelectric material, Ag_1-x_{1-}\textit{x} Pb_m_{\textit{m}} SbTe _m+2_{\textit{m}+2} (x = 0·2, m = 10), have been successfully prepared by high pressure method. The pressure-dependent electrical transport and thermoelectric properties of Ag_{0 ·8} Pb₁₀ SbTe₁₂ were studied at room temperature. Electrical resistivity and Seebeck coefficient decreases with an increase of synthetic pressure. Thermal conductivities are nearly constant when the pressure is lower than 4 GPa. The carrier concentrations of Ag_{0 ·8} Pb₁₀ SbTe₁₂ were tuned by more than a factor of 100 through changing of synthetic pressure. These results indicate that high pressure technique provides a viable and controllable way of tuning the electrical transport properties for AgPb_m_{\textit{m}} SbTe_{m + 2}_{\textit{m} + 2}.