耳声顺图与鼓膜状态的关系

猕猴猴头标本的正常声顺图与活猴的无明显差异,声顺图的主要特性都和人耳正常声顺图的相近。在猴头标本上可以在直视条件下较准确地改变中耳结构的状态以研究声顺图的变异规律,为解释各种形状声顺图的成因并为耳科病理诊断提供实验依据。本文介绍鼓膜在硬化、松弛、有附着物、活动受阻、穿孔等各种状态时声顺图的特性,其中一部分图形在文献上已有的声顺图图谱中还未见有描述。     

经豚鼠下鼓道口记录耳蜗电图

豚鼠是听觉机能研究最常应用的动物,在其颅骨的鼓泡上,有一卵圆形的小孔,称为下鼓道口,在此插入电极,可抵鼓岬部,能够很好地记录出耳蜗电图。此方法简便、可靠,不需要打开乳突,是从鼓岬部记录耳蜗电图的一种新途径,在听觉机能研究及生理学实验教学中具有广泛的应用价值。     

耳声顺图与听骨链及鼓室状态的关系

本文介绍在猴头标本上听骨链固定或中断、鼓室内压力及温度变化、鼓室密封或通大气、鼓室积液等状态对耳声顺图的各种影响。听骨链固定时平均可使声顺图振幅减低约2/3,听骨链中断平均可使之增大3倍多。声顺图的峰位置有时可偏离鼓室与外耳道的压力平衡般不超出±20mmH_2O 的范围。鼓室声阻抗的大小对声顺图的振幅有重要影响。鼓室积液时声顺图的振幅和形状与积液的量、积液的粘稠度及积液与鼓膜的相对位置等都有关系。     

温度及膜中蛋白质含量与膜粘度和膜中分子排列方向的关系

本实验用闪光诱导的瞬间二向色性方法测量了不同温度以及不同蛋白质含量下菌紫质分子在脂质囊泡膜中的旋转扩散运动.根据旋转扩散运动得到了温度和蛋白质含量与膜粘度以及分子在膜中排列方向的关系.温度和蛋白质的含量都影响膜的粘度,但并不影响蛋白质分子在膜中的排列方向.     

THE REVERSAL OF MITOCHONDRIAL MEMBRANE

An electron microscope study of mitochondria in hamster liver and kidney cells has revealed that at some points the outer membrane of these organelles is continuous with the inner membrane. Also, at such points the discontinuous components of the membrane pairs have free endings. The outer and the inner membranes of a mitochondrion, therefore, may not be two different and distinct entities, as has been conventionally assumed, but may rather be a part of the same unit. Such a morphological structure would make the intramitochondrial substance accessible to the cytoplasmic substance through the intermembrane channel. This structure would also facilitate the swelling of a mitochondrion either by an unfolding of the cristae, or a sliding of the two membranes, or by both these processes occurring simultaneously.     

金鱼精子质膜和核膜的区域特异性

本文结合采用扫描和透射电子显微镜(包括冷冻断裂-蚀刻、超薄切片以及细胞化学染色法),研究了金鱼精子的超微结构特征,结果表明金鱼精子的质膜和核膜都具有区域特异性:1)精子质膜内大部分区域含有许多蛋白颗粒,但在特定区域内,蛋白颗粒呈有序排列,构成晶格状结构。2)精子头颈部和尾部均有液泡密集之处,凡是覆盖着液泡区的质膜内,几乎都不含有蛋白颗粒。3)液泡区能被细胞化学方法染成致密色,表明内含糖蛋白。4)核膜孔只集中存在于靠近颈部的核膜上,而其他部分则没有。本文对上述诸点进行了讨论。     

三氯乙烯对脂质体膜通透性的影响及其破膜效应

本文通过测定脂质体膜对水的通透性及脂质体对被包裹血红蛋白的释放率,研究了三氯乙烯对脂质体的作用.观察到在低浓度时,三氯乙烯能增加蛋卵磷脂脂质体的通透性,随着浓度的增加有破膜释放的效应.     

伴刀豆球蛋白A与巨噬细胞膜上受体作用下膜变形性及细胞吞噬能力变化

本文采用图像分析、相差显微、生物活性测定等技术,研究ConA与巨噬细胞膜受体结合后对细胞行为与功能的影响. ConA与受体结合后巨噬细胞膜面积增大、变形性和吞噬能力增强、细胞产热量增加,表明细胞膜结构与功能发生变化.本实验是将图像分析技术用来研究相对图像采集速度要慢得多的活细胞特性的一次成功尝试.     

显微红外研究巨噬细胞膜电融合后膜蛋白二级结构的变化

首次尝试了将显微傅里叶变换红外光谱术应用于研究电融合后细胞膜蛋白质二级结构的变化,发现脉冲电场作用于细胞具有穿透效应,施加电脉冲后,整个细胞的蛋白质体系能量增加,表明电泳冲对蛋白的二结构影响很大;同时,还发现用唾液酸苷酶和蛋白酶Ｐｒｏｎａｓｅ分析处理巨噬细胞膜表面后,膜上蛋白质二级结构无序化程度增加,用酶适度处理的细胞将更易发生电融合。     

呼吸链底物和抑制剂对线粒体内膜流动性的影响

用DPH和ANS标记大鼠肝线粒体内膜,以稳态荧光偏振法,研究了呼吸链底物和抑制剂对内膜流动性的影响。1.苹果酸+谷氨酸、琥珀酸分别为底物,均能引起内膜流动性增加。2.琥珀酸对含心磷脂的脂质体的膜流动性无影响。3.在鱼藤酮存在的条件下,苹果酸+谷氨酸对内膜流动性的增加作用消失,但琥珀酸的作用仍然存在。有氰化钾时则琥珀酸的作用消失。4.不论外加底物存在与否,鱼藤酮使内膜的流动性下降,而氰化钾则使之增加。抗霉素A亦可使内膜的流动性增加。上述结果表明:线粒体内膜流动性与其功能密切相关。电子沿呼吸链传递使线粒体内膜流动性增加,这种变化可能与呼吸链成分的氧化还原态有关。     

HPD对人工膜的光敏作用

本文用ESB、荧光和冰冻断裂电子显微镜技术在分子水平上研究了血卟啉衍生物(HPD)作用于人工膜的光敏作用过程,损伤细胞膜的途径以及各种因素的影响.结果表明,HPD光敏作用与羟基·OH有关的动力学过程和靶分子密切相关.光照HPD的主要靶物质是不饱和分子,双键是其重要的进攻部位,由此导致脂质过氧化和膜的破坏.但这并不一定是引起膜损伤的唯一途径.HPD光敏作用也可破坏靶分子的空间排列或构象,从而导致膜结构的无序和损伤.牛血清白蛋白可以加强HPD的光敏作用.此外,HPD的光敏作用还受温度,光照时间、HPD和靶物质的浓度等因素的影响.     

THE MEMBRANE SYSTEM OF STREPTOMYCES CINNAMONENSIS

The plasma membrane bounding the cytoplasm immediately inside the hyphal wall of Streptomyces cinnamonensis may not retract from the hyphal wall. When it does retract from the wall, it appears as a single dark line in some sections and as 2 dark lines separated by a light zone in others. The membrane system consists of mesosomes and endomembrane structures. The mesosomes are those membrane structures whose derivatives appear to be the plasma membrane. The endomembrane structures, in the present report, are those that appear to have been derived from either the cytoplasm or the limiting membranes of the pre-existing membrane structures. All membranes seem capable of proliferation, a mechanism obviously responsible for the growth of the individual membrane structures and for the origin of many new ones. The mesosomes, according to their limits, are of 2 distinct types, the open mesosomes and the closed mesosomes. The open mesosomes are partially enclosed by limiting membranes, leaving the unenclosed sides limited by the wall. These mesosomes, when old, usually in aerial hyphae, may become attached to the wall and somewhat deleted from their limiting membranes. The individual membranes in their interior may appear disfigured. The closed mesosomes are completely surrounded by the limiting membranes. These mesosomes, as well as endomembrane structures, retain their original positions in the cytoplasm even in the older aerial hyphae, and the membranes in their interior usually remain practically as distinct in the aerial hyphae as they are in the substratal hyphae. New mesosomes and endomembrane structures are being formed continuously as the mycelium develops. The mesosomes, as a rule, occupy more or less the peripheral regions of the cytoplasm, while the endomembrane structures distribute themselves widely in the cytoplasm and also in the nucleoids. The appearance of the unit membranes, being double-layered (2 dark lines separated by a light line), is not consistent. The membranes as a whole are more resistant to degeneration than the cytoplasm and the nucleoids.