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131.
集周代社会诗歌文大成的《诗经》 ,既是我国古代的一部光辉文学著作又是周代社会的一部百科全书。然而前人多从文学的角度去研究其价值 ,而很少涉及到它所反映的其他社会内容 ,例如周人的宗教哲学观等。从《诗经》的大量篇章中 ,论证周人宗教哲学观在《诗经》的表现并进而分析周人之宗教哲学与殷人宗教哲学的相承相因相革的关系 ,从而论述周人宗教哲学反映于《诗经》的内容 ,是周人对殷人宗教哲学的继承和发展。 相似文献
132.
本文综述了二碘化钐引起的分子内还原偶联反应,包括分子内酮一烯还原偶联、酮一炔还原偶联、频哪醇偶联和其它有关还原偶联反应。 相似文献
133.
Yue-qin Qiu Xue-fen Yang Xian-yong Ma Yun-xia Xiong Zhi-mei Tian Qiu-li Fan Li Wang Zong-yong Jiang 《Journal of Zhejiang University. Science. B》2017,18(6):492-500
The expression of the cell death-inducing DNA fragmentation factor α-like effector (CIDE) family including Cidea, Cideb, and Cidec was significantly increased in mouse and human models of obesity. However, there was less information on these genes’ expression in pigs. Here, we hypothesized that different fat accumulation between lean (Duroc×Landrace×Yorkshire gilts, DLY) and obese (Lantang) pigs was attributed to porcine CIDE-modulating lipid metabolism. Our data showed that Cidea and Cidec were expressed at a high level in adipose tissue, and at a relatively high level in skeletal muscle, whereas Cideb was mainly expressed in the liver in both breeds of pig. Lantang pigs had higher white adipose and skeletal muscle Cidea and Cidec mRNA abundance, and hepatic and muscle Cideb mRNA than DLY pigs. Lipid metabolism-related genes including sterol regulatory element binding protein 1c (SREBP-1c), hepatocyte nuclear factor-4α (HNF-4α), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), fatty acid synthase (FASN), diacylglycerol O-acyltransferase 1 (DGAT1), and DGAT2 showed a higher expression level in adipose tissue from obese pigs than in that from lean pigs. Lantang pigs exhibited higher mRNA abundance for liver SREBP-1c, HNF-4α, and PGC-1α, and higher skeletal muscle SREBP-1c, HNF-4α, PGC-1α, and DGAT2 expression, as compared with DLY pigs. However, the perlipin2 mRNA levels in adipose tissues, liver, and skeletal muscle were significantly lower in obese pigs than in their lean counterparts. Furthermore, plasma non-esterified fatty acid (NEFA), glucose, and triacylglycerol (TAG) levels were greater in obese pigs than in lean pigs. Finally, data from correlation analysis further found that CIDE mRNA expression was positively correlated with back fat thickness (BFT), abdominal fat mass (AFM), and the levels of NEFA, TAG, and glucose in the two breeds. Collectively, these data revealed that the porcine CIDEs possibly modulated lipid metabolism and contributed to the development of fat deposition and obesity in Lantang pigs. 相似文献
134.
对数控技术应用专业职业能力的调查研究 总被引:1,自引:0,他引:1
数控人才的严重短缺已成为制造业普遍关注的问题。加快数控技术应用型人才的培养已成为高等职业教育的重要任务之一。构建“五双”为特征的人才培养模式,是实现职业教育人才培养目标的重要途径和手段.能够最大限度满足用人单位的需求。 相似文献
135.
136.
谢琥 《中国教育技术装备》2004,(1):18-19
通过语文教学中运用网络的案例分析,证明了网络教学是有利于激发学生学习兴趣,有利于分层教学的实施,有利于构建平等的师生关系和高效轻负的教学模式。 相似文献
137.
本文通过实验 ,比较全面和系统的研究了RL电路零输入时的自感现象。不仅研究了时间常数、电流比对自感现象的影响 ,而且还特别研究了灯泡的灯丝温度在闪光亮度上的变化 ,从而得出一些有价值的实验结论 相似文献
138.
数字图书馆未来的信息服务模式 总被引:3,自引:0,他引:3
阐述数字图书馆概念以及产生的网络环境对读者服务的影响及图书馆未来的信息服务模式。 相似文献
139.
发展现代网络教育的关键在于教育资源的建设,而改进资源的重用性和通用性是教育改革的重要环节.本文介绍了教育资源元数据及目前流行的几种网络教育资源元数据标准,重点从基于CELTS(教育部教育信息化技术标准委员会制定的技术规范)的网络多媒体课件制作基本原理着手,介绍一种基于CELTS元数据标准的多媒体课件制作方法及过程,旨在通过推广和应用,实现多媒体教育资源的共享和重用. 相似文献
140.
The pressurized reservoir is a closed hydraulic tank which plays a significant role in enhancing the capabilities of hydraulic driven robotics. The spring pressurized reservoir adopted in this paper requires comprehensive performance, such as weight, size, fluid volume, and pressure, which is hard to balance. A novel interactive multi-objective optimization approach, the feasible space tightening method, is proposed, which is efficient in solving complicated engineering design problems where multiple objectives are determined by multiple design variables. This method provides sufficient information to the designer by visualizing the performance trends within the feasible space as well as its relationship with the design variables. A step towards the final solution could be made by raising the threshold on performance indicators interactively, so that the feasible space is reduced and the remaining solutions are more preferred by the designer. With the help of this new method, the preferred solution of a spring pressurized reservoir is found. Practicability and efficiency are demonstrated in the optimal design process, where the solution is determined within four rounds of interaction between the designer and the optimization program. Tests on the designed prototype show good results. 相似文献