Oligosaccharide synthesis by enzymatic transglycosylation

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ΔF508 frequency and associated haplotypes near the cystic fibrosis locus in the Yugoslav population

Summary Chromosomes from 19 unrelated Southern Yugoslav families in which cystic fibrosis (CF) occurs were analysed for the presence of the ΔF508 mutation, using polymerase chain reaction amplification followed by dot blot and polyacrylamide gel analysis. Of the 38 CF chromosomes, 15 (39.5%) carry the ΔF508 deletion. Restriction fragment length polymorphism haplotypes for KM19/PstI, XV2c/TaqI and J3.11/PstI marker loci were determined and are compared for a total of 34 N and 37 CF chromosomes.     

桂西壮族手皮纹的分析

本文对广西西部500例健康壮族大、中学生的手皮纹进行了观察分析,计算出各型指纹频率、指纹脊线总数、指纹频度指数、atd角度、a-b脊线数、τ距比、主线横向指数、皮纹花样出现率、掌褶纹出现率共九项基本参数,并将这些数值与汉族作了比较,桂西壮族的手纹与汉族既有相似之处,又有本民族的特点。     

人体外周血淋巴细胞核损伤指标的比较研究

核异常作为组织特异性的遗传毒理体内短期检测法,现已日益受到重视。它比微核测试更敏感和合理。核异常包括多种形式的核损伤,而它们与致癌因子的损伤有着不同程度的相关性。本文以r-射线作为致癌与诱变因子,在人体外周血淋巴细胞中系统地比较研究了常用核损伤指标:微核、核变形、核碎裂和核固缩等的剂量(0-5Grag)一反应关系,并作线形回归分析。作者认为,作为人体淋巴细胞核异常测试法,应包括微核,核变形及核碎裂3个核损伤指标。     

Laser-transected microtubules exhibit individuality of regrowth, however most free new ends of the microtubules are stable

To study the possible mechanism of microtubule turnover in interphase cells, we have used the 266-nm wavelength of a short-pulsed Nd/YAG laser to transect microtubules in situ in PtK2 cells at predefined regions. The regrowth and shrinkage of the transected microtubules have been examined by staining the treated cells with antitubulin mAb at various time points after laser irradiation. The results demonstrate that microtubules grow back into the transected zones individually; neither simultaneous growth nor shrinkage of all microtubules has been observed. The half-time of replacement of laser-dissociated microtubules is observed to be approximately 10 min. On the other hand, exposure of the core of the microtubule, which is expected to consist almost completely of GDP-tubulin, by transecting the internal regions of the microtubule does not render the remaining polymer catastrophically disassembled, and most transected microtubules with free minus ends do not quickly disappear. Taken together, these results suggest that most microtubules in cultured interphase cells exhibit some properties of dynamic instability (individual regrowth or shrinkage); however, other factors in addition to the hydrolysis of GTP-tubulin need to be involved in modulating the dynamics and the stability of these cytoplasmic microtubules.     

马铃薯未传粉子房离体培养诱导双单倍体植株

以MS为基本培养基,附加不同水平的生长素,培养未传粉马铃薯子房,经三年试验,从两个品种中获得了双单倍体的绿色小植株,(2n=2x=24);从分化绿苗力很强的球状愈伤组织中,又不断地分化出许多绿色小植株。绝大多数品种,都可以诱导出愈伤组织,一般诱导率为70％左右。品种的基因型和培养基中的生长素种类与水平在愈伤组织分化绿苗中起着重要作用。通过扦插和试管微型薯培养,可以大量繁殖试管苗,这为马铃薯单倍体育种提供了较有利的条件。     

泡状饶氏藻营养细胞的超微结构研究

本文报道我国特有的一种绿藻门植物－泡状饶氏藻营养细胞的超微结构特征,植物体由3层细胞组成,外层细胞最小,细胞质比较丰富,含有较多的各种细胞器,液泡体积较小,中层细胞具有很大的中央液泡,细胞质成为贴壁的薄层,各种细胞器结构仍清晰可见,内层细胞极度液泡化,细胞质呈现退化状态,周生的片状叶绿体上有许多大小不等的穿孔,使叶绿体呈网孔状外貌,叶绿体主要由许多成对的类囊体组成,叶绿体上往往有几个蛋白核,蛋白核经常被1或2条类囊体穿过,呈现分隔状,本文也报道了泡状饶氏藻的线粒体,质体,内质网,高尔基体和核内微管的结构特征,根据泡状饶氏藻的类囊体形态与Ulva mutabilis非常相似以及蛋白核的超微结构特征,它与石莼科植物可能有较密切的亲缘关系,属于绿藻门中进化的类群。     

Development of shoot inHydrangea macrophylla I. Terminal and axillary buds

The structure of shoots, in particular of winter buds, ofHydrangea macrophylla was examined. The non-flower-bearing shoot is usually composed of a lower and an upper part, between which a boundary is discernible by means of a distinctly short internode. This internode is the lowermost of the upper part, and it is usually shorter than the internodes immediately above and below, although the internodes tend to shorten successively from the proximal to the distal part of the shoot. Variations exist in the following characters among the terminal bud, the axillary bud on the lower part of the shoot and the axillary bud on the upper part: (1) length of bud; (2) character of the outermost pair of leaf primordia; (3) degree of development of secondary buds in the winter bud; and (4) the number of leaf primordia. Usually, the terminal bud contains several pairs of foliage leaf primordia with a primordial inflorescence at the terminal of the bud, but the axiallary bud contains only the primordia of foliage leaves in addition to a pair of bud scales.     

用体外免疫法建立人—人抗流行性乙型脑炎病毒杂交瘤细胞株

利用单克隆抗体(McAb)进行病毒病的治疗是人们所关心的一个重大课题。 流行性乙型脑炎(乙脑)是一种严重威胁人民健康的急性传染病,病死率高,后遗症严重。国内外目前尚无特效疗法。陈伯权等用乙脑病毒皮下或腹腔感染3周龄小白鼠24、48小时及5天后,分别用乙脑病毒51-8McAb进行治疗,平均治愈率分别为78％、73％及22％。