聚氯乙烯增塑糊流变行为的研究——Ⅳ.表面活性剂的影响

本文研究了各类表面活性剂对聚氯乙烯增塑糊流变行为的影响。阴离子表面活性剂使其增塑糊有较高致流值,呈明显假塑性流动;阳离子和非离子表面活性剂使其增塑糊有低的表观粘度,接近牛顿型流动。测定了聚氯乙烯粒子表面的Zeta电位和接触角,并讨论了表面活性剂影响增塑糊流变性能的机理。     

Spectrophotometric investigation of complex formation of an oxime PAM-4Cl with palladium(II) and its analytical application

The colour reaction of 4-hydroxyiminomethyl-1-methylpyridinium chloride (PAM-4Cl) and palladium(II) chloride has been investigated. The optimum reaction conditions, spectral characteristics, conditional stability constant and composition of the yellow water-soluble complex have been established. A new spectrophotometric method is proposed for the microdetermination of PAM-4Cl.     

自制与进口氯化十六烷基吡啶抑菌作用的比较研究

以液体稀释法比较了自制与进口十六烷基吡啶作用于4种口腔常见微生物的最低抑菌浓度和最低杀菌浓度的实验结果,经t检验证明两者间无显著差异,提示自制氯化十六烷基吡啶的药效质量可靠。并就控制接种菌量及杀菌机理等问题作了初步探讨。     

125~I－后标记检测DNA－蛋白质交联物的研究

１２５~Ｉ－后标记法是庄志雄等人（１９９４）提出的一种检测ＤＮＡ－蛋白质交联物（ＤＰＣｓ）的新技术，该法在检测离体ＣＨＯ细胞ＤＰＣｓ的实验中已显示出敏感、快速和简便的优点。本研究表明，１２５~Ｉ－后标记法不仅能有效地检出由紫外光和铬酸钾诱导的ＣＨＬ细胞ＤＰＣｓ，并能有效而敏感地检测由铬酸钾和氯化镍引起的大鼠不同组织特别是白细胞ＤＰＣｓ形成的情况，是一种敏感的和可考虑应用于人群调查的ＤＰＣｓ检测方法。     

Raman and UV–vis spectroscopic study of polyaniline membranes containing a bulky cationic additive

Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λ_exc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl₂ solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI.     

小鼠背根神经节中三个不同的钙激活氯离子通道基因家族的表达(英文)

目的在背根神经节(dorsal root ganglion,DRG)中等大小感觉神经元中可以观察到钙激活氯离子流(I_(Cl(Ca)))。在坐骨神经损伤模型中,在大多数大中神经元上诱导出类似的氯离子流。本文旨在探讨引起这个离子流的分子基础。方法使用常规的定量RT-PCR方法检测在DRG中三个基因家族的表达,这三个基因家族都具有诱导I_(Cl(Ca))的特点。结果在成年小鼠的DRG中,分别显示了在正常状态和坐骨神经损伤3天后CLCA,Bestrophin和Tweety基因家族成员的转录产物。结论mBestl和Tweety2可能在损伤诱导的DRG神经元I_(Cl(Ca))中发挥作用。     

Effects of vitamin D3 and cyclosporin A on HgCl2-induced autoimmunity in Brown Norway rats

BACKGROUND.: Mercuric chloride (HgCl₂ induces a lymphoproliferative disorderand autoimmune glomerulonephritis in Brown Norway (BN) rats.This syndrome is the consequence of T cell-dependent polyclonalB cell activation and autoantibody production. We have previouslyshown that HgCl₂-induced autoimmune perturbations can be preventedin BN rats by the administration of cyclosporin A (CsA). Themost potent vitamin D₃ metabolite 1,25(OH)₂ D₃ (Vit D₃) sharescertain immunomodulatory properties with CsA. We therefore choseto compare the effects of Vit D₃ to those of CsA in BN ratstreated with HgCl₂ in order to establish whether Vit D₃ eitheralone or in combination with CsA can attenuate an autoimmunesyndrome in vivo. METHODS.: BN rats were treated with HgCl₂ according to a standard protocol.Subgroups of rats were also given CsA alone, Vit D₃ or syntheticanalogues of Vit D₃ alone, or combinations of both agents. Differentdoses and routes of administration were compared. The followingmarkers of disease activity were evaluated: mortality, peakproteinuria, serum IgE concentrations, and renal immunoglobulindeposition. RESULTS.: Disease activity was markedly attenuated in all rats treatedwith CsA alone. Vit D₃ and certain of its synthetic analoguesadministered alone also tempered the autoimmune process, butto a lesser extent than did CsA. The effect of CsA alone wasso potent, that no additive or synergistic effects could bedemonstrated when CsA was administered in combination with VitD₃. CONCLUSIONS.: Despite similar described immunomodulatory effects in vitro,CsA is clearly more effective than Vit D₃ in preventing HgCl₂autoimmune disease in BN rats. This suggests that there is adifference in the cellular targets of these two agents in vivo,and/or a difference in the potency with which HgCl2-triggeredimmune activation is suppressed.     

镉对小鼠免疫功能的影响

采用单只动物多项免疫功能检测法,观察了小鼠在免疫后,不同时间一次灌胃30mg/kg氯化镉(CdCl_2)及反复多次灌胃不同剂量的CdCl_2,对小鼠免疫器官重量,迟发型变态反应(DTH),抗体形成细胞(IgM-PFC)及抗体滴度的影响。结果表明:反复多次灌胃4.8 mg/kg CdCl_2对小鼠DTH有明显抑制作用,提示CdCl_2对动物免疫功能有一定影响。     

[3H]5-HT binding in post-mortem human cerebral cortex: methodological considerations

Summary The effects of different membrane preparations and assay conditions on [³H]5-HT binding to post-mortem human cortical tissue was studied. Optimal binding necessitated thorough removal of endogenous 5-HT and this was achieved either by hypotonic lysis or by preincubation of the membranes at 37C. Calcium chloride (4 mM) increased specific [³H]5-HT binding. The further addition of ascorbic acid (5.7 mM) or ascorbic acid and clorgyline (10 M) reduced specific [³H]5-HT binding.     

Role of volume-stimulated osmolyte and anion channels in volume regulation by mammalian sperm

The ability to maintain cellular volume is an important general physiological function. Swelling induced by hypotonic stress results in the opening of channels, through which ions exit with accompanying water loss (regulatory volume decrease, RVD). RVD has been shown to occur in mammalian sperm, primarily through the opening of quinine-sensitive potassium channels. However, as yet, direct evidence for the participation of anion channels in sperm RVD has been lacking. The chloride channel type ClC-3 is believed to be involved in RVD in other cell types. Using electronic cell sizing for cell volume measurement, the following results were obtained. (i) The anion channel blockers 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), tamoxifen and 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS) increased hypotonic swelling in concentration-dependent fashion, whereas verapamil (P-glycoprotein inhibitor) had little effect. The most potent, NPPB and DIDS, blocked RVD without affecting cell membrane integrity at effective concentrations. (ii) When gramicidin was included to dissipate Na+/K+ gradients, major secondary swelling was observed under hypotonic conditions. This secondary swelling could be reduced by NPPB, and suppressed completely by replacing chloride in the medium with sulphate, an ion which does not pass through chloride channels. It was deduced that the initial hypotonic swelling activated an anion channel through which chloride ions could then enter freely down a concentration gradient, owing to the lack of a counter-gradient of potassium. (iii) Taurine, an osmolyte often involved in RVD, does not appear to play a role in sperm RVD because lengthy preincubation with taurine did not alter sperm RVD response. Our observations provide direct evidence that a chloride channel (possibly ClC-3) is involved in the process of volume regulation in mammalian sperm.