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在350m氦氧模拟饱和及370m巡回潜水实验中,观察了16项肺功能指标及其衍生指标的定期监测结果。通过监测试图对暴露于高气压环境中人员的安全性、作业能力作出客观的评价,以加强医学保障,同时对大深度氦氧环境所导致的呼吸功能改变进行实验研究。  相似文献   

3.
本实验在我国首次进行的350m氦氧模拟饱和潜水试验中研究了人体肾上腺皮质及髓质功能的变化,这对潜水员的选拔及健康保障具有重要意义。 对象及方法 讲究对象 男性海军现役潜水员4名,经严格体检除外各种疾病。年龄20~22岁、身高169~173cm.体重64.5~68kg,潜水工龄2~4年。试验前均经过2.5个月严格适应性训练。  相似文献   

4.
模拟失重大鼠左心室乳头肌收缩性能及钙反应性的变化   总被引:4,自引:1,他引:4  
采用改进的Morey-Holton尾部悬吊大鼠模型拟失重状态和用离体乳头肌灌流技术,观察模拟失重大鼠左心室乳头肌收缩性能与钙反应性的变化过程。结果表明,模拟失重1周,收缩性能呈增高趋势;2周时,收缩性能有降低趋势;4周时,收缩性能明显降低,主要表现为等长张力降低29.2%,达到张力峰值的时间延长10.4%,舒张时间则呈降低趋势。另外,模拟失重4周大鼠乳头肌对Ca^2+的反应性均较相应的 对照组明显  相似文献   

5.
The isolation and cellular localization of a basic protein (histone) from central nervous tissue have been previously reported. In the tissues previously studied (nervous tissue, testis, liver, spleen, kidney, ovary), the basic protein was restricted in distribution to the nuclei of neurons and spermatogonia. In the present study, the temporal appearance of the histone within neurons and the changes in its distribution during ontogenesis were examined. The reaction between a fluorescent immune γ-globulin prepared against this purified tissue-specific histone and the neurons from the dorsal root ganglia of the rat was investigated. The dorsal root ganglia examined were those from fetuses, 2-, 10-, and 40-day-old rats, and from adult rats. At the earliest stages, only the nucleoli reacted. Subsequently, threads of fluorescent material were seen to emerge from the nucleoli. The extent of this reaction between the immune globulin and the threads within the nuclei continued to increase with maturation. No changes in fluorescence localization during development could be seen in the nuclei of neurons in the cerebellum or brain stem. The role that this tissue-specific histone may play in cell function is discussed.  相似文献   

6.
赫杰  苗桂英  赵海成 《植物研究》2002,22(1):26-29,T001
运用Bernhard染色方法研究了小麦根端分生组织细胞核仁在细胞周期中的变化。结果显示,间期核仁染色很深,能够区分出纤维中心(FC)、致密纤维组分(DFC)和颗粒组分(G),而染色质被漂白,在染色质间可以观察到细小的RNP颗粒。进入前期,在染色质的边缘有小的RNP颗粒分布。中期,染色体周边分布着类似于间期核仁的深染的大RNP颗粒,形成一个不完全连续的“鞘”状结构;在染色体内部看不到类似核仁的深染颗粒。到了后期时,仍可见RNP“鞘”状结构的存在。进入末期,这些RNP植物逐渐由“鞘”脱离,最后参与新核仁的形成。这些结果表明,核仁解体后的物质直接转移到了中期染色的表面,并形成不连续的表层,没有进入染色体的内部。  相似文献   

7.
小麦返白系返白期间Rubisco变化研究   总被引:1,自引:0,他引:1  
以小麦返白系和对照矮变1号为材料,选用返白系三个特殊的时期,返白初期、全白期、复绿初期,对其叶片可溶性蛋白进行了Native-PAGE和SDS-PAGE的研究。结果表明:随着叶片白化,核酮糖1.5-二磷酸羧化酶/加氧酶(Rubisco)全酶谱带逐渐变小,全白叶全酶谱带消失,随着复绿全酶谱带又出现,并逐渐恢复。而且Rubisco大、小亚基(LS、SS)谱带减少幅度差异很大,大亚基减少远远大于小亚基。  相似文献   

8.
大鼠在模拟5 000米低氧下心力储备的动态变化   总被引:6,自引:0,他引:6  
目的和方法:采用电刺激大鼠坐骨神经引起心阴抗图相应参数变化来测算心力储备的方法,测定了大鼠在模拟5000m氏氧下不同时间心力储备的动态变化。结果:心力储备在低氧3d已开始增加,7d增加显著(P〈0.05),低氧10d及14d又降至接近正常组水平,低氧30d略低于正常水平;每搏储备的变化规律和变化量均与心力领略相近,低氧7d增加显著(P〈0.01),人低氧14d仍显著地对照组(P〈0.05);心率储  相似文献   

9.
小麦核仁的超微结构在细胞周期中的变化   总被引:7,自引:0,他引:7  
应用整体银染技术在电镜下对小麦(Triticum aestivum L.)根端分生细胞核仁在细胞周期中的超微结构变化进行了研究。结果显示,间期核仁染色很深,能够区分出纤维中心、密集纤维成分、颗粒成分和核仁液泡等结构;染色质上也布满大量染色浅的细小银粒。前期,随着核仁的解体和染色质的集缩,染色质的边缘逐渐出现深染的大颗粒;到前期末时,大量的核仁物质向染色体周围扩散并附着到其表面。中期染色体的周边分布着来自解体核仁的银染大颗粒,形成一个不大均匀也不完全连续的“鞘”状结构。后期仍可见这种“鞘”状结构的存在。进入末期,这些银染核仁物质逐渐由“鞘”脱离,彼此融合形成前核仁体,最后参与新核仁的形成。这些结果表明,核仁解体后的物质直接转移到了染色体的表面,并形成一个不连续的表层,没有进入染色体内部;染色体内部的银染颗粒与核仁及其解体物质无关  相似文献   

10.
Ultrastructure of spore maturation in the myxomycete Didymium iridis was investigated using morphometric analytical techniques. Changes in actual volume (μm3) and relative volume (Vv) of nuclei, autophagic vacuoles, mitochondria, microbodies, lipid droplets, and spore wall were described for spores in three stages of development. Stage I spores were newly formed, surrounded only by the cell membrane. Stage II spores were approximately 1 hr older than Stage I spores and possessed surface spines, but little if any additional wall material. Stage III spores were 24 hr old and possessed a fully formed, multilayered wall. The results of this study indicate that spore maturation in D. iridis is a multistep process involving a decrease in spore volume and coordinated changes in specific organelle compartments. From Stage I to Stage III, mean spore volume decreased by more than 50%. Percent volume data (Vv) showed that Stage I spores allocated volume equally to all measured organelles except microbodies and the spore wall, the latter of which had not yet begun to develop. By Stage II, only the nucleus and spore wall showed significant changes in Vv values, both increasing. In terms of actual volume, the nucleus, autophagic vacuole and spore wall increased by Stage II. Between Stages II and III the cell wall was the only component to increase in volume, all others decreased in volume. Our data indicate a close relationship between a decrease in organelle volume and an increase in cell wall volume in the Stage III spore. The autophagic vacuole and the cell wall dominated the volume of the Stage III spore while the remaining volume was allocated unequally to the other components.  相似文献   

11.
目的:探讨在低氧性脑损伤发生过程中,Na+Ca2+ 交换体在细胞内钙超载中的作用。方法:采用全细胞膜片钳方法,在急性分离海马神经元上观察低氧对Na+Ca2+ 交换电流的电流电压(IV) 曲线的影响。结果:在整个膜电位水平,Na+Ca2+ 交换电流幅值均不同程度的增加,在正膜电位水平呈现一显著的外向电流。10 mV 时,电流幅值从(92 .83 ±20.8)pA上升到(130 .67 ±26.88)pA( P<0 .05) ,而在50 m V,其电流幅值从(- 74 .67 ±11 .84)pA上升到(- 58 .5±10 .71)pA(P< 0 .05)。结论:低氧时Na+Ca2+ 交换电流呈外向性,这种改变有利于低氧后通过Na+Ca2+ 交换的外向转运方式排出细胞内钠,并交换钙进入细胞  相似文献   

12.
柳叶烟草愈伤组织分化期间抗氰呼吸的改变   总被引:1,自引:0,他引:1  
继代培养的柳叶烟草愈伤组织有明显的抗氰呼吸。交替途径的相对贡献约占总呼吸的29—38%;但仍以细胞色素途径为主,约占总呼吸的44—51%。接种在分化培养基上的愈伤组织在发生组织分化和芽原基形成期间,交替途径运行量占总呼吸的41—47%,承担呼吸电子传递的主要部分;而细胞色素途径只占总呼吸的29—32%。交替途径运行程度的增高可能与烟草愈伤组织的分化有一定相关性。  相似文献   

13.
大鼠动情周期中生殖轴系微循环血量的变化   总被引:1,自引:0,他引:1  
吴素英  张珉 《生理学报》1990,42(5):509-513
本文采用放射性生物微球技术,对雌性大鼠动情周期中丘脑下部-垂体-卵巢轴系的微循环血量进行了测量。结果指出,周期各期丘脑下部和垂体的血流量无显著差异(p>0.05)。卵巢血流量在动情后期最大,动情期最小,两期血流量的差异显著(p<0.02)。子宮血流量以动情后期最大,间情期仍维持在较高水平,动情期最小。动情后期和间情期与动情期比较均有显著差异(分别为p<0.01和P<0.05)。输卵管血流量动情期最大,动情前期最小,两期血流量的差异也有显著性(p<0.05)。由此表明,卵巢、子宫和输卵管血流量有明显的周期性波动。血流量的多寡与其生理机能状态和性激素的变化有关。  相似文献   

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