轴浆转运在神经再生中的作用

夹伤坐骨神经阻断标记蛋白在轴浆中的快、慢转运。3天后转运再现。第14天的转运距离与对照相似,说明再生神经的转运动能基本恢复。用快、慢转运测出的14天平均再生速度分别为1.77±0.14与1.96±0.07mm/d,比对照神经的正常生长速度快6.3—7倍,提示再生需要更多的转运物质。进一步发现再生神经中某些标记蛋白(慢转运波W1)的转运速度为10.25±0.66mm/d,约比对照快1倍,因此这些标记蛋白可能包含适应再生需要而加速转运的结构和功能物质。     

Cytogenetic characteristics of a population of Chironomus riparius Meigen 1804 (Diptera, Chironomidae) from a polluted Po river station

A population of Chironomus riparius from a Po river station near Moncalieri (a trace-metal polluted station) was studied. In this population was established a great variability of band structure of polytene chromosomes as well as paracentric heterozygous inversions, deletions, deficiencies, partial breaks, diploid chromosome fragments, and changes in functional activity and appearance of heterochromatin. In arms A through F, some bands had an increased size compared to the standard chromosomic map. Some bands appeared in a heterozygous or normal homozygous state or were amplified. In all arms, many condensed stable bands appeared in the decondensed state when compared to the standard map. Asynaptic zones in arms E and G as well as heterozygous Balbiani rings and NORs were established. Very often the 4th chromosome was almost completely heteropycnotic and looded like a pompon chromosome. For the first time in this species, a high frequency of ectopic pairings of different arms was observed. Telomeric regions involved in ectopic pairings had a granular appearance, as did some centromeres. The hypothesis is advanced that such a high frequency of structural rearrangements could be correlated with genomic distribution of specific mobile elements.     

从睡眠剥夺树鼩（TBC）尿液提取内源性“睡眠因子”（sleep factor）的研究

本研究报道从睡眠剥夺（ＳＤ）４８—７２ｈ的灵长类原宗（ｐｒｉｍｉｔｉｖｅｓｔｏｃｋ）Ｔｕｐａｉａｂｅｌａｎｇｅｒｉｃｈｉｎｅｎｓｉｓ（ＴＢＣ）提取内源性“睡眠因子”（ｓｌｅｅｐｆａｃｔｏｒ）Ｓ２Ｃ和Ｓ４Ｂ。收集的尿液经超滤,清液冻干经ＳｅｐｈａｄｅｘＧ１５分离得到ＦｒａｃｔｉｏｎⅠ－Ⅴ。活性测定发现Ｆｒａｃｔｉｏｎ－Ⅲ（Ｓ２Ｃ）呈现显著δ－增强促眠效应。经ＳｅｐｈａｄｅｘＧ２５和ＳｅｐｈａｄｅｘＬＨ２０进一步净化的Ｓ４Ｂ也呈现显著δ－增强促眠效应。     

埃及血吸虫毛蚴表皮板的观察

埃及血吸虫毛蚴表皮板共有4排,各排数目为6:9:4:3。除第1排之外,其他各排的表皮板均由无纤毛的嵴所分隔,在第1与第2排之间的环嵴中,除第1排各板底边中央小凹处各有1感受器外,尚可见4对感受器。第2与第3排的环嵴内可见16—20个感受器。此外,于体之两侧第3排表皮板间各见1个排泄孔。顶突似六边形,于其两侧各有1个侧腺开口,其内侧可见14个感受器。本文在讨论中与前人对本虫毛蚴表皮板的描述做了简单比较。     

中国喀斯特地区微生物群落结构和功能的研究进展

频繁的人类生产活动使植被遭到破坏,造成基岩裸露的石漠化现象,严重制约了喀斯特地区自然和社会经济的发展,随着生态修复工程的大力开展,微生物群落的结构和功能在生态修复中逐渐受到重视,因为微生物作为喀斯特生态系统的重要组成部分,不仅在物质循环过程中起着重要作用,也在喀斯特生态系统修复中占有十分重要的地位。所以微生物群落结构和功能的研究可以作为衡量生态系统稳定性的重要指标。就中国喀斯特地区的典型植被恢复的不同阶段、成土过程、不同的土地利用方式、矿山修复过程以及不同水域中的微生物群落结构及功能等方面的研究状况进行系统梳理,结合实例综合论述喀斯特地区生态修复过程中微生物作用的研究进展,以期为喀斯特地区生态修复提供参考。     

渗透胁迫对高粱根K~＋吸收的影响

以ＣａＳＯ４０．５ｍｍｏｌＬ－１溶液培养高粱得到低钾植株,在渗透胁迫下当ＰＥＧ－１０００使外界渗透势下降时,刺激了高粱根高Ｋ＋亲和系统的净Ｋ＋积累,其表观Ｋｍ值和Ｔｍａｘ值分别为１８μｍｏｌＬ－１和４９．６μｍｏｌｇ－１ＤＷｈ－１。此高亲和系统不受可渗物质乙二醇和外界ｐＨ变化的影响,为蛋白质合成抑制剂环己酰亚胺抑制。     

Biodegradation of 4-nitrophenol by indigenous microbial populations in Everglades soils

The Everglades in South Florida are a unique ecological system. As a result of the widespread use of pesticides and herbicides in agricultural areas upstream from these wetlands, there is a serious potential for pollution problems in the Everglades. The purpose of this study was to evaluate the ability of indigenous microbial populations to degrade xenobiotic organic compounds introduced by agricultural and other activities. Such biodegradation may facilitate the remediation of contaminated soils and water in the Everglades. The model compound selected in this study is 4-nitrophenol, a chemical commonly used in the manufacture of pesticides. The mineralization of 4-nitrophenol at various concentrations was studied in soils collected from the Everglades. At concentrations of 10 and 100 microg/g soil, considerable mineralization occurred within a week. At a higher concentration, i.e., 10 mg/g soil, however, no mineralization of 4-nitrophenol occurred over a 4-month period; such a high concentration apparently produced an inhibitory effect. The rate and extent of 4-nitrophenol mineralization was enhanced on inoculation with previously isolated nitrophenol-degrading microorganisms. The maximum mineralization extent measured, however, was less than 30% suggesting conversion to biomass and/or unidentified intermediate products. These results indicate the potential for natural mechanisms to mitigate the adverse effects of xenobiotic pollutants in a complex system such as the Everglades.     

Structure of the thymus gland of the rat in the prenatal and early postnatal periods of development after exposure to tetracycline during the period of fetogenesis

Structure of the thymus in Wistar rats has been studied during antenatal and early postnatal periods of ontogenesis by means of histological, morphometric and electron microscopic methods. Theraputic doses of tetracycline hydrochloride have been administered during fetogenesis (15-20 days of pregnancy). An accelerated formation of the thymic structures, cellular blasttransformation in the thymic cortex and movement of lymphocytes from the cortex into medulla and increased secretory activity of epithelioreticulocytes have been revealed. The data obtained are considered as a display of the organ's immune response to tetracycline administration.     

Use of DNA polymorphism detected by M13 phage DNA in population studies]

Hypervariable "minisatellite" regions detected in human genome by wild-type phage M13 DNA were found to have high polymorphism and somatic stability. Analysis of individual specific patterns of hybridization of 44 human DNAs from the Kirov province is presented. Molecular weight of fragments varied from 2 to 6 kb. Mean frequency of a fragment in the population under study is p = 0.294 +/- 0.158. The mean number of fragments per individual is 11.6 +/- 1.8. Comparison between the Kirov population and that of Krasnodar studied earlier was carried out. The mean genetic distance between Kirov and Krasnodar populations calculated according to Nei is 0.2082. The possibility of using in population-genetic studies of hypervariable DNA markers having fingerprint type of hybridization is discussed.