Catecholamine metabolism in the vas deferens and the adrenal gland with special reference to the central catecholamine-depleted state

Experiments were carried out to elucidate the role of central catecholamines in regulating catecholamine metabolism in the vas deferens and adrenal gland of the rat. Rats were injected intracerebroventricularly (i.c.v.) with either vehicle or 6-hydroxydopamine (6-OHDA). Groups of animals pretreated with vehicle or 6-OHDA (i.c.v.) were injected intraperitoneally (i.p.) with alpha-methyl-para-tyrosine (AMT), a tyrosine hydroxylase inhibitor. Catecholamine turnover rates were estimated by determining norepinephrine or epinephrine content after administrating AMT.Central norepinephrine and dopamine contents decreased significantly (p<0.05) after treatment with 6-OHDA and AMT. The norepinephrine content of the vas deferens of rats pretreated with 6-OHDA was markedly reduced (p<0.001) after administration of AMT, whereas that of the vehicle-treated rats remained unchanged. Administration of 6-OHDA had no effect on the norepinephrine or epinephrine content of the adrenal gland.The present results indicate that central monoaminergic neurons have an inhibitory effect on the adrenergic neurons of the vas deferens. In contrast, this inhibitory regulation does not appear to be exerted on the adrenal glands.     

关于C_(11)A_7·CaF_2稳定性的研究

本文采用X射线衍射分析方法,研究了影响C_(11)A_7·CaF_2稳定性的因素,结果表明C_(11)A_7·CaF_2在1450℃以内,能够稳定存在;Mgo,K_2O对C_(11)A_7·CaF_2稳定性没有影响;Na_2O、P_2O_5和CaO能与C_(11)A_7·CaF_2发生反应、分别生成少量NC_6A_3、Ca_5F(PO_4)_3和C_3A,但在硅酸盐水泥熟料的正常煅烧制度下,反应程度较低,对C_(11)A_7·CaF_2稳定性不大.熟料中铝酸盐相存在的形式,主要取决于氟在熟料中的分布,CaF_2掺量较低,温度超过1350℃,C_(11)A_7CaF_2消失,生成C_3A;CaG_2掺量较高时,温度高达1450℃,熟料中的铝酸盐相仍为C_(11)A_7·CaF_2,而不生成C_2A.     

Nras loss induces metastatic conversion of Rb1-deficient neuroendocrine thyroid tumor

Mutations in the gene encoding the retinoblastoma tumor suppressor predispose humans and mice to tumor development. Here we have assessed the effect of Nras loss on tumor development in Rb1 heterozygous mice. Loss of one or two Nras alleles is shown to significantly reduce the severity of pituitary tumors arising in Rb1(+/-) animals by enhancing their differentiation. By contrast, C-cell thyroid adenomas occurring in Rb1(+/-) mice progress to metastatic medullary carcinomas after loss of Nras. In Rb1(+/-)Nras(+/-) animals, distant medullary thyroid carcinoma metastases are associated with loss of the remaining wild-type Nras allele. Loss of Nras in Rb1-deficient C cells results in elevated Ras homolog family A (RhoA) activity, and this is causally linked to the invasiveness and metastatic behavior of these cells. These findings suggest that the loss of the proto-oncogene Nras in certain cellular contexts can promote malignant tumor progression.     

科斯社会成本问题与政府管制的效率实现

科斯在其社会成本一文中提出经济行为具有相互性,并很好地将交易成本理论运用在经济行为中,通过交易成本为零的理想世界到交易成本为正的现实世界进行条件转换分析,提出了外在性存在的根源及解决途径主要包括自愿协商(市场)、企业、政府和法律四种;提出由市场解决不好的问题,不一定政府就解决的很好;提出应从社会净收益最大化的角度来看,关键在于避免较严重的损害的观点,即如何使损失最小化或使社会经济运行效率最大化。他的这些思想,使经济学家注意到了交易成本的各种后果,大大地提高了经济的解释力。为政府更有效地进行管制提供了理论支撑。     

整机老炼条件的优化设计

本文通过工程实例，阐述如何利用现有信息来设计产品的老炼条件，以使它在保证产品达到规定可靠性的前提下尽量节省成本     

粘合衬对服装舒适性影响的研究

探讨了粘合衬与粘合工艺对服装透气性、透湿性及透水性影响的规律。得出服装的舒适性虽由面料决定,但辅料(粘合衬)的影响也不可忽视。粘合衬的涂胶种类,粘合衬本身的透气性与透湿性,以及非织造粘合衬底布的单位重量,机织粘合衬底布的覆盖系数等,均对服装舒适性有影响,从而为衬料的选择,以及粘合工艺参数的设定,提供了依据。     

氧化物半导瓷中晶界势垒的起源

提出了一个关于氧化物半导瓷晶界势垒起源的新观点，认为晶界势垒起源于烧结过程中外界氧在晶界中的扩散，与材料的结构、化学缺陷、掺杂、外界气氛、烧结工艺、组成状态等有密切关系，并用此理论解释了许多实验现象。     

一个快速的二进制多重精度gcd算法

求两个整数的最大公因子（gcd)的经典的Euclid算法时间复杂度为O（ln^3n)，不适宜于多重精度运算。论文证明了gcd的相关性质，提出了一个基于二进制的、适用于多重精度运算的改进算法，其时间复杂度为O（ln^2n)。     

交织扩展Golay码编译码器实现方案的研究

论述了交织编码的工作原理，给出了一种交织扩展Ｇｏｌａｙ码的改进型软件设计方案，用ＴＭＳ３２０Ｃ２５实现了其编译码器并给出了模拟实验结果。实验结果表明，它能准确地纠正不大于７２比特位的差错；处理１２８×１２８×８比特位的一幅图像数据的运行时间为０．４１２ｓ．     

广谱型C60修饰电极电位传感器的研究

吸附型Ｃ６０修饰玻碳电极可作为一种广谱响应的电位传感器，对十余种无机及有机季铵盐阳离子，其电位－浓度对数值呈一定的线性关系，该电极制备方便、响应速度快，稳定性好。本文还从电极表面Ｃ６０晶型结构出发，对电极的响应机理进行了初步探讨。