大鼠Harderian腺中卟啉的释放机理

大鼠Ｈａｒｄｅｒｉａｎ腺存在大量卟啉洒物质。分离细胞抽提物的荧光激发、发射光谱与标准原卟啉Ⅳ几乎完全重叠，说明大部分卟啉是原卟啉Ⅳ。荧光显微镜下分离的细胞发出很强的红色荧光，在分泌颗粒间隙荧光较分泌颗粒处更强，胆囊收缩素８肽（ＣＣＫ－８）、乌拉胆碱（Ｂｅｔｈ）皆不以刺激卟啉向胞外的释放。这些结果说明，Ｈａｒｄｅｒｉａｎ腺细胞向胞外释放卟啉不是通过胞吐进行的。     

a2及5—HT2受体与甘氨酸受体之间的对话

在新鲜分离的神经细胞模型上,运用制霉菌素（ｎｙｓｔａｔｉｎ）穿孔膜片钳方法研究ａａ２及５－ＨＴ２与甘氨酸受体之间对话的分子机理,发现：刺激ａ２受体,抑制腺苷酸环化酶,减少ｃＡＭＰ的生成,合ＰＫＡ活性降低,从而增强甘氨酸受体的功能;刺激５－ＨＴ２受体,激活磷脂酶Ｃ（ＰＬＧ）,增加甘油二酯（ＤＡＧ）的生成．ＤＡＧ增强不依赖Ｃａ＾２＋的新型ＰＫＧ（ｎＰＫＧ）的活性,从而增强甘氨酸受体的功能,ａ２及５－Ｈ     

黄芪多糖对荷瘤小鼠红细胞免疫功能的影响

采用红细胞Ｃ３ｂ受体花环率（ＲＢＣ－Ｃ３ｂＲＲ），红细胞免疫复合物花环率（ＲＢＣ－ＩＣＲＲ），血清中红细胞Ｃ３ｂ受体花环抑制率（ＲＥＩＲ）和红细胞Ｃ３ｂ受体花环促进率（ＲＦＦＲ）等四个指标，研究了黄芪多糖对Ｓ１８０Ａ小鼠肝癌（ＨＥＰＡ）和小鼠红细胞免疫功能的影响。结果表明，黄芪多糖能明显提高荷瘤小鼠的ＢＢＣ－Ｃ３ｂＲＲ和ＲＦＥＲ，降低ＲＢＣ－ＩＣＲＲ和ＲＦＩＲ。这一结果说明黄芪多糖对荷瘤小鼠红细胞免疫有明显的促进作用。     

琥珀酰CCK—7对小鼠记忆的影响

琥珀酰ＣＣＫ－７是对ＣＣＫ－８进行分子改构后获得的一种新药，本实验以一次被动回避反应模型观察比较了这种改构物与ＣＣＫ－８对小鼠记忆巩固过程的影响，同时探讨了ｓｕｃ－ＣＣＫ－７影响记忆过程的剂量－效应关系以及时相－效应关系。结果表明：（１）ｓｕｃ－ＣＣＫ－７促进记忆的有效剂量为１００－２００μｇ／ｋｇ，小于１００μｇ／ｋｇ无明显效应。（２）ｓｕｃ－ＣＣＫ－７增强小鼠记忆的效应在电击后４８ｈ最明显，７     

大黄牡丹汤组方对急性胰腺炎模型大鼠腺泡细胞 分泌功能的影响

摘要: 目的 研究大黄牡丹汤组方( RPDP) 对急性胰腺炎( Acute pancreatitis,AP) 模型大鼠 胰腺腺泡细胞外分泌功 能和腺泡细胞内钙离子浓度( FI) 的影响。方法 SD 大鼠灌胃 RPDP 以制备大黄牡丹汤组方含药血清( RPDP-S) ; SD 大鼠分为假手术组和 AP 模型组,分离胰腺腺泡细胞并与 RPDP-S 共同孵育,测定腺泡细胞淀粉酶分泌水平和 FI 变化。结果 AP 模型大鼠腺泡细胞分泌淀粉酶水平较假手术组显 著升高( P ＜ 0. 05) ,经 RPDP-S 处理的 AP 模 型大鼠腺泡细胞分泌淀粉酶水平显著降低( P ＜ 0. 05) ; FI 随 AP 模型病程延长而升高( P ＜ 0. 05) ,RPDP-S 可抑制 AP 模型大鼠腺泡细胞内 FI 升高( P ＜ 0. 05) 。结论 ＲPDP 通能抑制 AP 大鼠胰腺腺泡细胞的外分泌功能,抑制腺 泡细胞内钙离子的升高,降低腺泡细胞内 FI 超载。     

胰腺腺泡细胞胞浆游离钙浓度的测定及药物作用的研究

本文建立了用荧光指示利Fura－2测定胰腺腺泡细胞胞浆游离Ca2＋浓度（［Ca2＋］i）的实验技术,包括：胰腺腺泡的分离制备;Fura—2／AM的负载;腺泡悬液的荧光光谱测量等．测定了胰腺腺泡细胞［Ca2＋］i。的静息值和卡巴可促腺泡细胞［Ca2＋］i升高的剂量—效应关系及动力学过程,并研究了柴胡总皂甙对胰腺腺泡细胞［Ca2＋i］的影响．发现0．01mg／ml浓度的柴胡总皂甙使胰腺腺泡细胞［Ca2＋］。明显升高,0．1mg／ml浓度时可使［Ca2＋］。升高到静息值的3倍,提示柴胡总皂甙的促酶分泌作用是通过胞内［Ca2＋］i升高介导的．     

八肽胆囊收缩素抗血清翻转针刺耐受的电生理学研究

动物整体水平研究证实，八肽胆囊收缩素抗血清（ＣＣＫ－ＡＳ）可翻转电针耐受，而ＣＣＫ－ＡＳ本身不影响基础痛阈。本文采用记录神经元放电的方法证明：脑室注射ＣＣＫ－ＡＳ能翻转对长时间电针产生耐受效应的大鼠丘脑束旁核痛兴奋神经元（ＰＥＮ）和痛抑制神经元（ＰＩＮ）的电活动，使电针镇痛效应重新出现。而脑室注射正常兔血清（ＮＲＳ）对产生电针耐受效应的ＰＥＮ和ＰＩＮ的电活动无影响。从细胞水平得到的这一结果与整体水平研究的证据相一致。提示，内源性ＣＣＫ－８参与电针耐受可能是电针镇痛受到拮抗的机制之一。这一发现同时为临床医学实践提供了进一步的依据。     

缺氧对脑星状细胞内皮素系统基因的影响

目的：内皮素－１（ＥＴ－１）广泛存在于中枢神经系统（ＣＮＳ）并通过其受体Ａ和Ｂ（ＥＴＡＲ，ＥＴＢＲ）产生众多的血管和非血管活性作用，内皮素转移酶（ＥＣＥ）－２ＣＮＳ中主要的ＥＣＥ形式，它将几乎无活性的ＥＴ－１转换成活性的ＥＴ－１。脑星状细胞（ＡＣ）是ＣＮＳ重要组成部分，可产生ＥＴ－１并合有其受体结合点。缺氧可使ＡＣ分泌ＥＴ－１水平增高，但是否对ＡＣＥＴ－１ｍＲＮＡ水平有调节作用则尚无报道。也未见有     

Cu（Ⅱ）,Pb（Ⅱ）,Zn（Ⅱ）,Cd（Ⅱ）痕量金属离子的浮选分…

以焦磷酸根（Ｐ２Ｏ７＾４－）为配体，二六烷基三甲溴化铵（ＣＴＭＡＢｒ）为鼓泡剂，对Ｃｕ（Ⅱ），Ｐｂ（Ⅱ），Ｃｄ（Ⅱ）等４种金属离子的浮选分离进行了研究。讨论了ｐＨ值，氮气流速、Ｐ２Ｏ７＾４－的浓度、ＣＴＭＡＢｒ的浓度、金属离子浓度对浮选率的。到了其最佳分离条件，对Ｃｕ（Ⅱ）－Ｃｄ（Ⅱ），Ｐｂ（Ⅱ）－Ｃｄ（Ⅱ），Ｚｎ（Ⅱ）－Ｃｄ（Ⅱ）等二元组分进行了较好的分离。     

Cu（Ⅱ），Pb（Ⅱ），Zn（Ⅱ），Cd（Ⅱ）痕量金属离子的浮选分离法研究

以焦磷酸根（）为配体，十六烷基三甲溴化铵（ＣＴＭＡＢｒ）为鼓泡剂，对Ｃｕ（Ⅱ），Ｐｂ（Ⅱ），Ｚｎ（Ⅱ），Ｃｄ（Ⅱ）等４种金属离子的浮选分离进行了研究。探讨了ｐＨ值、氮气流速、的浓度、ＣＴＭＡＢｒ的浓度、金属离子浓度对浮选率的影响．找到了其最佳分离条件，对Ｃｕ（Ⅱ）－Ｃｄ（Ⅱ），Ｐｂ（Ⅱ）－Ｃｄ（Ⅱ），Ｚｎ（Ⅱ）－Ｃｄ（Ⅱ）等二元组分进行了较好的分离。     

VIP occurs in intrathyroidal nerves and stimulates thyroid hormone secretion

Vasoactive intestinal polypeptide (VIP) is known to have powerful effects on the secretion from several endocrine and exocrine glands, and occurs in nerves with a ubiquitous distribution in the body. This infers that neuronal VIP may be a regulator of such secretion, and there is evidence that it is involved in the regulation of exocrine pancreatic function. Previous studies have shown that adrenergic and cholinergic nerves participate in the regulation of thyroid hormone secretion. We describe here combined immunohistochemical and immunochemical studies which show that the thyroid of several species is supplied with VIP-containing nerve fibres that surround blood vessels and run between and along thyroid follicles and that in the mouse neuronal VIP participates in the regulation of thyroid hormone secretion through a mechanism that is mediated by cyclic AMP.     

Human preprovasoactive intestinal polypeptide contains a novel PHI-27-like peptide, PHM-27

Vasoactive intestinal polypeptide (VIP), a 28-amino acid peptide originally isolated from porcine duodenum, is present not only in gastrointestinal tissues but also in neural tissues, possibly as a neurotransmitter, and exhibits a wide range of biological actions (for example, relaxation of smooth muscle, stimulation of intestinal water and electrolyte secretion and release of insulin, glucagon and several anterior pituitary hormones). As the structure of porcine and bovine VIP shows several similarities to those of mammalian glucagon, secretin and gastric inhibitory peptide (GIP), VIP is considered to be a member of the glucagon-secretin family. Recently, we have found that VIP is synthesized from a precursor, pro-VIP (molecular weight (Mr) 17,500), in human neuroblastoma cells and that the primary translation product of the mRNA encoding VIP is prepro-VIP (Mr 20,000). In an attempt to elucidate the primary structure of the precursor, we have now cloned the DNA sequence complementary to the mRNA coding for human VIP and analysed the nucleotide sequence. The entire amino acid sequence of the precursor, deduced from the nucleotide sequence, indicates that the precursor protein contains not only VIP but also a novel peptide of 27 amino acids. The peptide, designated PHM-27, differs by only 2 amino acids from PHI-27, a peptide recently isolated from porcine intestine, and is also closely related in sequence to VIP.     

周口店北京人遗址环境地质条件及地质病害机理分析

自周口店北京人遗址区被发现后的几十年以来,由于自然和人为因素的影响,在各发掘点内出现了诸多不同类型的地质病害,严重威胁着遗址区的安全与保护.基于此,通过现场及室内试验对遗址区环境工程地质条件进行了分析并在此基础上通过岩石薄片镜下鉴定、岩石化学分析及崩解试验等对影响遗址区病害的因素及机理做了分析.结果发现,周口店遗址区7个发掘点共有20处类型不一、规模不等、变形程度不同的潜在地质病害点.其破坏的原因可以归结为地质、环境及人类活动3个因素,其中着重讨论了环境因素的影响.环境因素分析结果表明,不同地点处由于其胶结物成份不同所以环境因素对其的影响方式也不同.图12,表3,参8.     

Prostaglandins and the synergism between VIP and noradrenaline in the cerebral cortex

We have previously shown that vasoactive intestinal peptide (VIP) and noradrenaline (NA) interact synergistically to increase cyclic AMP levels in mouse cerebral cortical slices. The pharmacological mechanism of this synergism is the potentiation by NA, through alpha 1 adrenergic receptors, of the stimulatory effect of VIP on cAMP formation. A similar interaction has been confirmed in guinea pig cerebral cortex and in discrete nuclei of the rat hypothalamus. Furthermore VIP and NA interact synergistically to depress the spontaneous activity of identified neurons in rat neocortex. At the cellular level, this synergistic interaction suggests that VIP- and NA-containing neuronal systems may converge, at least in part, on the same target cells to increase cAMP levels in the cerebral cortex. At the molecular level, the interaction may occur at various steps in signal transduction, between receptors, intramembrane transduction processes or intracellular effector mechanisms. Here we report that the alpha 1-adrenergic potentiation of the increases in cAMP elicited by VIP involves the formation of arachidonic acid metabolites and is mimicked by prostglandins F2 alpha and E2.     

京剧服装中戏曲符号的呈现及美学特征

以京剧服饰艺术性的文本语境为出发点,从美术学角度出发,运用符号学分析方法,探寻了其作为一个符号系统,在色彩、图案、款式上的艺术特点、美学特征及规律.指出京剧服装是京剧舞台人物塑造的重要艺术手段,是中国传统美学的一种存在原则,一种精神实在,一种艺术美学,从而使人们可以更加深入了解京剧服饰的独特魅力.     

Dopaminergic stimulation of prolactin release

Prolactin (PRL) secretion from anterior pituitary is believed to be under tonic inhibitory control of dopamine (DA) released from the tubero-infundibular dopaminergic neurones into the hypophysial portal blood. Inhibition of PRL release by DA seems to be mediated by sereospecific DA receptors located in PRL cells. Apomorphine and various ergot alkaloids such as bromocryptine mimic the inhibitory effect of DA both in vivo and in vitro, presumably by a direct agonist action on these 'inhibitory' receptors. We now report that PRL secretion in primary cultures of rat pituitary cells can be stimulated by DA when concentrations a thousand times lower than those required for inhibition are used. Secretion rates above basal release can also be induced by apomorphine and bromocryptine when the 'inhibitory' receptors are blocked with certain DA receptor antagonists.     

Quantal transmitter secretion from myocytes loaded with acetylcholine.

It is well known that transmitter secretion requires specialized secretory organelles, the synaptic vesicles, for the packaging, storage and exocytotic release of the transmitter. Here we report that when acetylcholine (ACh) is loaded into an isolated Xenopus myocyte, there is spontaneous quantal release of ACh from the myocyte which results in activation of its own surface ACh channels and the appearance of membrane currents resembling miniature endplate currents. This myocyte secretion probably reflects Ca(2+)-regulated exocytosis of ACh-filled cytoplasmic compartments. Furthermore, step depolarization of the myocyte membrane triggers evoked ACh release from the myocyte with a weak excitation-secretion coupling. These findings suggest that quantal transmitter secretion does not require secretory pathways unique to neurons and that the essence of presynaptic differentiation may reside in the provision of transmitter supply and modification of the preexisting secretion pathway.     

Functional architecture of an intracellular membrane t-SNARE

Lipid bilayer fusion is mediated by SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) located on the vesicle membrane (v-SNAREs) and the target membrane (t-SNAREs). The assembled v-SNARE/t-SNARE complex consists of a bundle of four helices, of which one is supplied by the v-SNARE and the other three by the t-SNARE. For t-SNAREs on the plasma membrane, the protein syntaxin supplies one helix and a SNAP-25 protein contributes the other two. Although there are numerous homologues of syntaxin on intracellular membranes, there are only two SNAP-25-related proteins in yeast, Sec9 and Spo20, both of which are localized to the plasma membrane and function in secretion and sporulation, respectively. What replaces SNAP-25 in t-SNAREs of intracellular membranes? Here we show that an intracellular t-SNARE is built from a 'heavy chain' homologous to syntaxin and two separate non-syntaxin 'light chains'. SNAP-25 may thus be the exception rather than the rule, having been derived from genes that encoded separate light chains that fused during evolution to produce a single gene encoding one protein with two helices.     

命名数据网络中VIP转发方案的性能优化

命名数据网络(named data networking,NDN)是信息中心网络(information centric network,ICN)的一个典型实例,是未来网络一种可能的架构.为优化NDN的转发性能,要求转发平面能根据不同的网络环境自适应地调整转发策略、选出最优的转发接口.“虚拟兴趣分组”(virtual interest packet,VIP)架构是一种基于NDN的联合动态转发与缓存的网络架构,通过VIP架构对转发方案进行了性能优化.VIP架构的转发方案使用了背压算法,该算法在网络处于轻负载状态时时延较大,为此引入偏差函数进行优化.为检测优化效果,对原始VIP架构和优化后的VIP架构的转发性能进行了仿真实验对比.实验结果显示,优化后的转发方案相比原方案在转发时延上有一定降低.且由于偏差函数的引入不会增加原转发方案的时间复杂度,因此提出的方法可以优化VIP转发方案的性能.