高度木质化材料的冰冻切片技术

高度木质化植物材料的切片难度很大,应用常规切片方法不容易取得高质量的图版。本文介绍的冰冻切片方法,不需要进行长时间的软化处理、以及繁琐的脱水、包埋等过程,切片还进行不同的染色或组织化学测定,是一种快速、简捷和有效的制片方法。 其关键步骤是选好甘油浓度, 冰冻温度和展片步骤。     

成熟玉米秆组织结构切片方法的比较研究

于玉米成熟期选择健壮茎秆的基部第三节间为材料,采用徒手切片法、冰冻切片法、石蜡切片法、薄切片法等4种方法,比较不同方法的玉米茎秆组织结构切片质量,为研究玉米茎秆结构与其倒伏的关系奠定技术基础。结果表明:徒手切片法是获得成熟玉米秆组织结构切片较为方便、快速的方法,切片面积较大,适合大范围观察统计;冰冻切片法是获得成熟玉米秆组织结构较快的方法,切片面积较小,适合小范围观察;薄切片是获得高质量成熟玉米秆组织结构切片的最好方法,但切片面积太小,适合高倍数显微观察和小范围电镜扫描观察组织结构;石蜡切片不适合作为成熟玉米秆的组织切片方法。研究认为,徒手切片法是最适合成熟玉米秆组织结构观察研究的制片方法。     

微小组织冰冻快速制片技术

目的摸索提高微小组织冰冻快速制片质量的方法。方法针对小组织冰冻切片中常常出现组织切完、多粒组织切片不全、冰晶、染色不均匀等问题,采用预先制作冷冻平台、快速冷冻等方法来制作优质的冰冻切片。结果组织铺平可使组织切片完整,快速冷冻可减少冰晶形成,使组织结构更清晰,及时固定和加温染色可使细胞核染色更鲜艳,核、质对比明显。结论组织铺平、速冻、固定、染色等都是提高微小组织制片质量的关键。     

杂草果实的冰冻切片技术

介绍一种快速、简便的杂草果实解剖技术。以4种木质化程度高且能够漂浮的杂草果实为材料进行冰冻切片, 经过材料固定、前处理、样品冷台固定、冷冻切片、展片、染色和观察并拍照等操作步骤, 可以获得清晰的果实解剖照片, 直观地揭示杂草果实适应漂浮的显微结构。杂草果实冰冻切片方法的优点是不需要对材料进行长时间的软化处理以及繁琐的脱水和包埋等过程。其关键环节是适宜的甘油浓度、冰冻温度和展片步骤。其中, 15%的甘油浓度进行前处理最合适。     

杂草果实的冰冻切片技术

介绍一种快速、简便的杂草果实解剖技术。以4种木质化程度高且能够漂浮的杂草果实为材料进行冰冻切片,经过材料固定、前处理、样品冷台固定、冷冻切片、展片、染色和观察并拍照等操作步骤,可以获得清晰的果实解剖照片,直观地揭示杂草果实适应漂浮的显微结构。杂草果实冰冻切片方法的优点是不需要对材料进行长时间的软化处理以及繁琐的脱水和包埋等过程。其关键环节是适宜的甘油浓度、冰冻温度和展片步骤。其中,15%的甘油浓度进行前处理最合适。     

对徒手切片技术的一点改进

徒手切片技术运用在植物学实验教学中的历史较为悠久,在石蜡切片之前,基本上使用徒手切片。它的优点在于可以观察新鲜材料组织和细胞的天然色彩,看到活体细胞结构状态,所以徒手切片运用在植物学实验教学中比较普遍。为了克服传统徒手切片技术中的不足,我们进行了改进,改为皮套加刀片。这种切片方法切片速度快,软硬质材料都可以切,不需要任何夹物,既经济适用,又简单易行。     

有关半薄切片技术的几点改进

半薄切片技术是近几十年来才发展起来的一门新兴技术。它的优点是:能够更好地保存细胞成分和精细结构;切片厚度为0.3—2微米,染色程序简便,切片的清晰度高,可观察到细胞内较细微的结构。这种技术已广泛应用于细胞学、胚胎学和解剖学等研究领域。目前,有关半薄切片的染色方法已有详细报道,但对半薄切片的捞取、色度调整和刀痕的遮掩等国内还介绍不多。     

动物病理组织制片过程的体会

组织切片技术是兽医科学研究和临床学观察组织病理形态变化，进行疾病诊断的一种重要方法，制作优质的组织切片，取材新鲜，固定完全，脱水彻底，透明适度，浸蜡充分，切片要薄，染色良好，如在某一步骤上不加注意，即将会造成事倍功半，但在实际工作中，常由于某些人为因素，使切片质量不佳，甚至影响研究和诊断的结果，本文介绍了我室制片过程中人为现象及其原因和纠正方法的体会，从而制出优质的组织切片标本。     

植物冰冻切片条件的优化及其与石蜡切片在组织化学应用中的比较

冰冻切片是植物组织学研究中一项重要的实验技术,冷冻温度和冷冻时间是决定切片质量的关键因素。通过比较15种冰冻切片条件,得出植物组织直接冰冻切片较适宜的冷箱温度、冷台温度和冷冻时间。同时,通过对5种植物的不同组织进行组织化学染色,比较了新鲜材料直接冰冻切片与常规石蜡切片在不同化学成分鉴定上的异同及各自的适用范围。结果表明,对于多糖、蛋白质和角质,两种切片方法的鉴定结果比较一致,但对于脂肪只能采用冰冻切片技术。研究结果对植物组织学实验和研究方法的改进具有一定的参考价值。     

树脂包埋半薄切片在视神经组织学和免疫组织化学研究中的应用

目的探讨半薄切片在视神经组织学和免疫组织化学研究中的应用,寻找一种视神经形态学研究和疾病诊断的有效方法。方法健康Sprague-Dawley大鼠视神经分别行树脂包埋制成半薄切片与石蜡包埋制成石蜡切片,分别采用HE、甲苯胺蓝染色及髓鞘碱性蛋白(myelin basic protein,MBP)免疫组织化学方法染色,光学显微镜下观察并比较半薄切片与石蜡切片染色结果的差异。结果石蜡切片HE和甲苯胺蓝染色均显示视神经髓鞘不着色,MBP免疫组织化学染色示MBP阳性着色较重,着色较紊乱,髓鞘着色不清晰。半薄切片HE及甲苯胺蓝染色均显示髓鞘呈环形,着色清晰,颜色对比鲜明;MBP免疫组化染色结果可见髓鞘呈环形,非特异性染色不明显,阳性对比显著,可清晰显示髓鞘结构。结论半薄切片在视神经组织学和免疫组织化学研究中优于石蜡切片,可用于视神经疾病的诊断和研究。     

人为干扰对小果野芭蕉群落生物量及多样性的影响

采用标准木法和回归分析法（乔木层）研究了小果野芭蕉群落在演替吕不同的压力条件下生物量和多样性的变化,结果显示,小果野芭蕉的侵入在正常情况下对群落生物量的影响并不显著,但由于人为干扰,可以明显地降低群落生物量。人为干扰是小果野芭焦群落长期保持在一个种群数量较大,物种多样性指较低和重要值较大的状态。轮歇丢荒地小果野芭蕉的侵入和迅速发展,是群落恢复演替过程中一种正常的途径。因此保持小果野芭蕉群落不受人为干扰是使其沿正常演替途径恢复的一种可行方法。     

液胶色谱柱复性在低分子量尿激酶原突变体（DscuPA—32K）中的应用

将构建一种具溶栓和抗栓以重功能尿激酶原突变体（DscuPA-32K)基因,在大肠杆菌中进行表达。由于DscuPA-32K分子较大并且表达量较高,目的的性质基本以包涵体的形式存在。包涵体中的蛋白质是无活性的蛋白质,为了获得有活性的蛋白质,就需要对包涵体进行变性及复性。尝试了一种新的凝胶色谱柱复性方法,并通过柱复性方法与常规的稀释复性方法进行了比较,发现柱复性方法明显优于稀释复性方法,具有成本低,效率高,并对目的的蛋白质（DscuPA-32K)进行了初步纯化等优点,尤其对酶这一类容易失活降解的蛋白质进行复性时,很值得进行推广应用。     

Societal Risk Perception in Arab Countries: The Case of Kuwait

The study was aimed at examining data on risk perception from an Arab country—Kuwait—in order to support the existence of an Arab group as regards the way hazards are perceived. The data were gathered in 2003 and 2004 on two Kuwaiti samples of young adults and adolescents. The questionnaire used was the one used in studies conducted in Egypt and France. It comprised 141 items. The overall mean value observed in the Kuwaiti sample was close to the one found in the Egyptian sample. The linear association between Kuwaiti and French ratings was moderate (0.70) and of the same magnitude as the one found between Egyptian and French ratings. The association between Kuwaiti and Egyptian ratings was greater (0.90). In 80% of the hazards, the specific differences observed between the Kuwaiti and French ratings were the same as the ones observed between Egyptian and French ratings. The whole set of findings supports the hypothesis that Kuwaitis and Egyptians, despite huge differences in the socioeconomic environments in which they live, perceive societal risks in a common way, a way that is different from the way Western Europeans perceive them.     

中国部分地区种子植物区系亲缘关系的研究

以植物属分布区类型的百分比为指标,分别采用系统聚类分析的最短距离法、最长距离法、中间距离法、重心法、离差平方和法、类平均法和可变法等7种方法,对中国46个地区的植物区系进行了分析研究,给出了其种子植物属的分布区类型的树状聚类图,求得各地区植物区系之间的亲缘关系。结果表明：在一定的经度范围内(中国东半部地区),两个地区植物区系之间的亲缘关系与其所处的纬度相关,即纬度相近其亲缘关系也相近,反之即疏远。运用系统聚类分析方法所得到的中国46个地区植物区系之间亲缘关系的结果与经典的理论基本吻合。     

A laboratory captured ‘giving way’ episode during a single-leg landing task in an individual with unilateral chronic ankle instability

An episode of ‘giving way’ at the ankle is described as excessive inversion of the rearfoot that does not result in an acute ankle sprain and is a unique feature associated with chronic ankle instability (CAI). Limited data currently exists describing the preparatory movement patterns and those that occur during an episode of ‘giving way. Therefore, this case report describes the movement patterns and the forces generated during an unintentional ‘giving way’ captured while an individual with unilateral CAI was performing a single-leg landing task in a research laboratory. The participant completed five single-leg landing trials for both limbs. 3D lower extremity kinematics and kinetics for the sagittal and frontal plane were extracted from 200 ms before and after initial contact (IC). Relative to the affected and un-affected single-leg landing trials, the ‘giving way’ episode was characterized by an increase in plantarflexion and hip extension moments before and after IC. The plantarflexion deviation dissipated (50 ms post-IC) and was followed by excessive ankle inversion. The ankle began to plantarflex again (150 ms post-IC) and the knee extended (50 ms post-IC) and adducted (100 ms post-IC). As a result, the ankle inversion angle plateaued at 150 ms post-IC. Furthermore, large sagittal plane internal joint moments were observed. In the frontal plane, the ‘giving way’ trial generated a large inversion joint moment which was counteracted by a large internal eversion joint moment. The observed plantarflexion and knee extension and adduction after initial contact likely contributed to preventing the ankle from continuing to invert and avoid an ankle sprain.     

黑腹果蝇杂交实验的教学改革

本文介绍关于黑腹果蝇杂交实验的一次教学改革尝试。讨论遗传学实验教学中,如何由常规的“验证性”教学改变为启发式的“发现式”教学,在本实验教学中,学生处于主导地位,自己选择实验组合,提出实验设计方案,独立完成实验内容;教师只是协助学生完成其实验内容。这种教学方法,充分发挥学生学习的主动性,培养学生独立思考和实际操作能力,激发学生的学习兴趣。 Abstract:The paper is concerned about a teaching and learning reform of hybridization experiment of Drosophila melanogaster.In the teaching of genetic experiment,we have adopted a new teaching and learning method which was a discovering way instead of tranditional method .In this way,students themselves selected the combination subject,put forward and carried out the whole experiment scheme.By the reform,we couldd find out that it was helpful not only to improve students' thinking and operating abilities but also to encourage their interests in genetics.     

乙型肝炎疫苗中游离抗原对免疫效果的影响

将按《生物制品规程》制备除氢氧化铝吸附方式不同外,其余所有过程均一致的疫苗各１０批,在ＨＢｓＡｇ含量相同前提下,于５００公升大罐内吸附制备的疫苗中游离抗原含量比在１０公升瓶内吸附制备的疫苗高４倍,两者均数分别为３０４．１ｎｇ／ｍｌ和７３．１ｎｇ／ｍｌ,吸附率分别为９７．９５％和９９．５１％;用ＲＰＨＡ测定游离抗原滴度前者也比后者高２倍;动物免疫效价（ＥＤ５０）高４７％。在上述吸附率范围内,游离抗原含量与ＥＤ５０呈正相关（ｒ＝０．７１７９Ｐ＜０．００１）。     

Vector analysis in a neural network

The responses of single units in the optic lobe of the blowfly Phormia terraenovae have been investigated using micro-electrode techniques and computer generation of optical stimulation. In order to test the idea that single units perform a “neural vector analysis” the optical stimulation was designed in such a way that the mathematical vector analytic capacity of the neurones could be investigated by using a single luminous dot moving in the proper way. The integrative mechanism of the neurone could be studied by using two dots moving in such a way that the inhibitory and excitatory components of the stimulus were related in precise ways. The data verify the notion of “neural vector analysis” and open the way for an analysis of motion perception and perceptual constancies on the basis of neural mechanisms.