成核效应蛋白在泡凝聚融合过程中作用的初步研究

为了探讨成核效应蛋白在泡凝聚、融合过程中的作用，作者研究了胆汁中主要的促成核蛋白系统—ＣｏｎＡ结合蛋白对模拟胆汁泡的形态与脂类组成的影响，发现ＣｏｎＡ结合蛋白在加快泡凝聚与融合的同时，也使泡胆固醇增加，磷脂减少，泡胆固醇／磷脂比增高，认为成核效应蛋白促泡凝聚与融合的本质是改变了泡胆固醇饱和度。作者的初步研究还发现泡相蛋白虽量微却具有强的促成核活性；几种已知的成核效应蛋白在泡相与微胶粒相的分布有差异；胆固醇结石患者与色素结石患者相比，泡蛋白的量与促成核活性均增高。通过泡蛋白亲和染色技术，还发现ＣｏｎＡ结合蛋白能与模拟胆汁泡形成脂质－蛋白复合体。作者认为，泡中成核效应蛋白的存在或量与质的改变，在泡凝聚与融合过程中起重要作用。     

周围剂量当量仪的研制

周围剂量当量仪研制是根据国际辐射单位和测量委员会（ＩＣＲＵ）３９号报告推荐的周围剂量当量而设计的一种数字化智能型辐射防护仪。方法采用能量补偿对探测器进行能响校正。结果补偿结果使得探测器在４７～２３０ｋｅＶ与ＩＳＯ推荐的Ｈ＊（１０）／Ｋａ值误差在５％以内。本文重点描述了周围剂量当量仪探测器部分的工艺结构和剂量学性能以及电子学测量部分的主要功能。结论通过实际应用我们初步获得的结论是由于该仪器可直接测量周围剂量当量，稳定性好且具有自动取平均值特点，它可做为实验室校准用测量仪器，又由于该仪器体积小，电池供电，读数面板又有背光功能，它也可以做为现场仪器用于辐射防护实践的现场测量     

Hormone receptors in vestibular schwannomas

Summary The possibility that steroid hormones play a role in vestibular schwannoma proliferation has been suggested by a number of investigators. There is conflicting information about the presence of steroid hormone receptors in these tumors. The aim of this study was to examine the expression of androgen, progesterone, glucocorticoid and estrogen receptor messenger ribonucleic acid levels (mRNA) in twenty-one vestibular schwannomas by either Northern blot analysis or the polymerase chain reaction (PCR).Glucocorticoid receptor mRNA was expressed in all twentyone tumors examined. Only two male specimens were positive for androgen receptor mRNA expression by PCR-Southern blot analysis. Thirty-three percent of the schwannomas (7/21) showed a strong band for progesterone receptor mRNA by PCR-Southern blot analysis; there were an equal number of males and females in this group. Estrogen receptor mRNA levels were undetectable in all tumors examined by PCR-Southern blot analysis. These studies suggest that the pattern of steroid receptor expression is different in schwannomas than in meningiomas. Individual vestibular schwannomas need to be examined for their steroid receptor mRNA expression mRNA expression to know whether they will be responsive.     

A study on contents of trace elemants Sr、Ni、Se~(4＋)in different parts of Jilinpanaxginseng

$ＢａｓｉｃＣｏｌｌｅｇｅｏｆｍｅｄｉｃａｌＳｃｉｅｎｅｓ；ＩｎｓｔｉｔｕｔｅｏｆＥｎｄｅｍｉｃＤｉｓｅａｓｅｓ     

Measurement of brain perfusion by volume-localized NMR spectroscopy using inversion of arterial water spins: accounting for transit time and cross-relaxation.

The theoretical model for perfusion measurement by NMR using arterial labeling of endogenous water is extended to include the effects of transit time and cross-relaxation of tissue water with macromolecules. Water magnetization in rat brain is monitored using the STEAM method to simultaneously determine the transit time, magnetization transfer rate constant, and perfusion. The results show that the transit time in rat brain is quite short, and thus its effect on perfusion measurement is small. It is also demonstrated both theoretically and experimentally that the steady-state effects of cross-relaxation with macromolecules on perfusion measurement are accounted for by a proper control experiment.     

Activation of phospholipase D by platelet-derived growth factor (PDGF) in rat C6 glioma cells: possible role in mitogenic signal transduction.

The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.     

重度联合免疫缺陷小鼠的繁育及其应用初报

应用带过滤罩的透明鼠在层流柜内繁育Ｔ和Ｂ淋巴细胞缺失的重度联合免疫缺陷（ｓｃｉｄ）小鼠获得成功，１９９３年５月至１９９４年４月，共繁育ｓｃｉｄ小鼠２２１只，寿命均超过１２个月。平均每窝产仔数为５．５只，显著低于对照组ＢＡＬＢ／ｃ小鼠，不育率为１４．９％，离乳率为８８．２％，与ＢＡＬＢ／ｃ小鼠相比均无明显差异。ｓｃｉｄ小鼠４～１０周龄的体重与同龄ＢＡＬＢ／ｃ小鼠相比无明显差异，微生物学检测均符合ＳＰ     

71例初产妇前置胎盘与人工流产相关性分析

目的:探讨初孕人工流产与再孕后前置胎盘发生率的相关性。方法:对1992年1月～2001年12月住院分娩的4046例初孕人工流产进行回顾分析,对影响前置胎盘发生率的因素进行x~2检验。结果:初产妇前置胎盘发生率为1.75％;人工流产次数越多,末次人工流产术后至本次妊娠时间间隔越短;人工流产术后有生殖道感染史者,前置胎盘发生率明显增高。结论:人工流产术是前置胎盘的高危因素,应加强育龄妇女的生殖健康宣传和教育,做到有计划受孕,减少非意愿妊娠的发生。     

局限缺血－再灌注心肌细胞内钙超负荷发生机制的探讨

本文通过犬急性心肌缺血－再灌注模型探讨缺血－再灌注心肌Ｃａ２＋超负荷的发生机制。当心肌持续缺血１５０ｍｉｎ，心肌细胞内Ｃａ２＋、Ｎａ＋增加、Ｋ＋降低；心肌细胞膜Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ、Ｃａ２＋－ＡＴＰａｓｅ活性降低，心肌组织丙二醛（ＭＤＡ）含量增加．而心肌缺血９０ｍｉｎ后，再灌注６０ｍｉｎ，与之比较细胞内Ｃａ２＋明显增加，伴Ｎａ＋升高、Ｋ＋降低，心肌细胞膜Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ、Ｃａ２＋－ＡＴＰａｓｅ活性降低，ＭＤＡ含量增加，说明缺血－再灌注过程中Ｎａ＋升高、Ｎａ＋－Ｃａ２＋交换增加，Ｃａ２＋－ＡＴＰａｓｅ活性降低是细胞内Ｃａ２＋超负荷发生的重要原因。     

硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用

研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。