乳鼠外周神经雪旺氏细胞的体外培养和纯化的研究

本文取５～７天ＳＤ新生大鼠坐骨神经剪碎,用０．２５％胰蛋白酶及０．０３％胶原酶在３７℃消化４５分钟,吹打分散后接种于培养瓶。培养基为含１０％胎牛血清的Ｆ１０。接种后４８小时,加入阿糖胞苷（Ａｒａ－ｃ,Ｓｉｇｍａ）１０－５ｍｏｌ／Ｌ处理,４８小时后换每毫升含神经生长因子（ＮＧＦ）１００μｇ的培养液,刺激雪旺氏细胞（ＳＣ）生长５～７天。此时根据成纤维细胞去除的情况,可再次加入Ａｒａ－Ｃ１～２天或转为无血清培养基一周。这种抗有丝分裂法结合无血清培养法,既能有效去除成纤维细胞,又能减少对ＳＣ的损伤,获得的ＳＣ纯净度可达９８％。     

鸡胚原始生殖细胞的分离和鸡鸭嵌和体的制备

探索了鸡胚12～17期血液中的原始生殖细胞(PGCs)迁移数量变化规律,将其在液氮中冷冻保存.并以Ficoll密度梯度离心、MiniMACS磁气分离、滤膜三种方法对PGCs进行分离,结果发现12～17期血液中均有PGCs存在,13期达到高峰约47.1±10.5个/μl,在血液中比例为0.0126%.冷冻保存3个月后解冻成活率达80%以上.三种分离方法所得的分离效果分别为95.7%、39.2%、63.0%,纯度为27.5%、8.4%、3.1%.将分离的原始生殖细胞以微注射法转移至14～15期麻鸭胚胎中制备了鸡鸭种间嵌和体,获得8只雏鸭(8/110).以鸡W染色体探针原位杂交法在早期鸭胚性腺中检测到鸡原始生殖细胞,嵌和率达84.2%(16/19).表明鸡原始生殖细胞能够迁移定居到鸭胚性腺中,并有可能增殖分化成有功能的配子.     

乙型肝炎病人重叠感染丙型肝炎的评价

应用ＥＬＩＳＡ和ＰＣＲ法检测５０２例乙肝病人血清,４０１例ＨＢｓＡｇ阳性血清中,有１１４例（２８．４％）抗－ＨＣＶ和ＨＣＶＲＮＡ双项阳性,２５例（６．２％）ＨＣＶＲＮＡ单项阳性;２１例（５．２％）抗－ＨＣＶ单项阳性。将ＨＢｓＡｇ乙肝病人分成ＨＢＶＤＮＡ,ＨＢｅＡｇ阳性组和ＨＢＶＤＮＡ,ＨＢｅＡｇ阴性组。前者抗－ＨＣＶ阳性率为１１．６％～２０．５％,ＨＣＶＲＮＡ阳性率为１６．２％～２０．５％。后者抗－ＨＣＶ阳性率为２０．２％～５５．６％,ＨＣＶＲＮＡ阳性率为２３％～６０．３％。结果说明长期携带ＨＢＶ者和慢性乙肝病人均可重叠ＨＣＶ感染。ＨＢＶＤＮＡ阳性组抗－ＨＣＶ和ＨＣＶＲＮＡ阳性率明显高于ＨＢＶＤＮＡ阳性组     

荧光法测定羽毛中的色氨酸含量

本文探讨了羽毛中色氨酸的荧光分析方法,将２～５ｍｇ的羽毛样品置于聚四氟乙烯管中,用１ｍｌ含０．５％可溶性淀粉的５ｍｏｌ／Ｌ　ＮａＯＨ为水解液,以纯氮为保护气体,在１１０℃水解２０小时,水解产物用６ｍｏｌ／ＬＨＣｌ中和,然后用Ｎａ２ＨＰＯ４－ＮａＯＨ的缓冲溶液（ｐＨ１１）稀释５倍,在激发波长２８０ｎｍ,发射波长３６２ｎｍ测定荧光强度及其浓度。经多次试验,结果较为满意,重现性较好,其相对标准偏差为０．６１％～３．００％。样品的回收率为９５．３％～１０２．１％。此法快速、简便,适用于各种羽毛的例行分析。     

泡桐叶片蛋白质提取方法的研究

２４个提取泡桐叶片蛋白质组合的试验结果表明,用ＵＫＣ（９．５ｍｏｌ／Ｌ尿素,５ｍｍｏｌ／ＬＫ２ＣＯ３,１．２５％ＣＴＡＢ,０．５％二硫苏糖醇,２％两性载体电解质ｐＨ３．５～１０,５％ＴｒｉｔｏｎＸ－１００）提取由１０％冷（－４０℃）三氯醋酸（丙酮配制,内含０．０７％的巯基乙醇）处理的泡桐叶片干粉提取出的蛋白质总量和种类最多。这表明该方法可用于泡桐叶片蛋白质的提取。     

植物材料表面消毒方法的改进

苹果枝条用０．１％ＨｇＣＩ2磁力搅拌消毒１５-２０ｍｉｎ,无菌水磁力搅拌清洗５次,每次５ｍｉｎ。污染率和杀死率在１０％以下,成功率９０％左右,且无褐化。     

不同卵龄小鼠卵母细胞激活和受精的比较研究(英文)

本实验比较了不同卵龄的小鼠卵母细胞受酒精人工刺激后的激活率和体外受精率,以探讨卵母细胞激活和受精的机制。向ＮＩＨ雌鼠腹腔注射孕马血清促性腺激素（ＰＭＳＧ）７．５单位,４８小时后注射人绒毛膜促性激素（ＨＣＧ）７．５单位,于不同时间杀小鼠,取卵母细胞与卵丘细胞的复合体（ＯＣＣ）。从注射ＨＣＧ后到取ＯＣＣ的时间视为卵母细胞的卵龄。将ＯＣＣ置于含８％酒精的Ｍ２中７分钟,再在Ｍ１６中培养５小时后,用０．３ｍｇ／ｍＬ的透明质酸酶去卵丘细胞。卵母细胞形成原核或速即卵裂为激活的标志。将ＯＣＣ加入已获能的精子悬液中,５小时后将从卵丘细胞中释放出来的卵母细胞转移到Ｍ１６中,次日发生卵裂为卵母细胞体外受精和激活的标志。小鼠卵母细胞卵龄为２０ｈ,其激活率为８１．６％,速即卵裂率为４８．０％;而卵龄进一步增加到２４ｈ,激活率和卵裂率转为下降（Ｔａｂｌｅ１）。而卵母细胞受精子激活和受精则不同,卵龄为１５ｈ,卵母细胞的体外受精率为４５．４％;随着卵龄的进一步增加,体外受精率则下降（Ｔａｂｌｅ２）。Ｆｉｇ．１显示：新排出的卵母细胞容易被精子激活而受精;卵龄较大的卵母细胞较易被酒精的人工刺激而激活。可能是卵母细胞从成熟到老化过程中,细胞的结     

HGV广东株和香港株NS5区部分基因的克隆及序列分析

采用ＨＧＶＮＳ５特异的２对引物,对两个香港株和一个广东株ＨＧＶＲＮＡ进行逆转录套式ＰＣＲ扩增,ＰＣＲ产物克隆入ｐＵＣ１９,重组质粒转化ＤＨ５α和ＪＭ１０９菌株。ＰＣＲ和酶切法鉴定阳性克隆,双脱氧链末端终止法测定核苷酸序列并进行同源性分析。结果发现核苷酸变异呈散在分布,三株间核苷酸和氨基酸序列同源性分别为９３．３％～９４％及９７％～９９．２％,与已报道的中国株（ＣＮ）相比,则同源性分别为９０％～９１．２％和９４％～９６．３％,与美国株（ＰＮＦ２１６１及Ｒ１０２９１）相比,为８７．１％～８９．５％和９５．２％～９７％,而与西非株（ＧＢＶＣ）相比,则达９１．４％～９３．８％和９７％～９７．９％。提示ＨＧＶＮＳ５区核苷酸和氨基酸序列相对保守,不同ＨＧＶ株存在一定的地区差异。     

非OI群霍乱弧菌在不同理化环境中产生色素的研究

本文报道了理化因素对非ＯＩ群霍乱弧菌的生长及产生色素的影响。实验结果表明,２５℃～３６℃、０％－３％ＮａＣｌ、ｐＨ７．４～９．０;４２℃、１％～３％ＮａＣｌ、ｐＨ５．０—１０．０为最佳生长环境,适宜生长,并有利于色素的产生。     

兔受精卵显微注射外源基因后体外培养的卵裂发育

从超数排卵的１４只母兔获得４３８枚受精卵,卵龄１６～２２小时．显微操作在带微分干涉和相差的Ｎｉｋｏｎ倒置显微镜下进行．注射针的尖端外也０．５μｍ,离尖端４０和８０μｍ处的外径分别为４．２和６．５μｍ．注射用外源基因是绵羊生长激素基因与ＭＴ－１启动基因藕连的线状ＤＮＡ溶液（１ｎｇ／μｌ）．１４０枚注射的受精卵和未注射的１４５枚受精卵（对照）,在Ｈａｍ’ｓＦ—１０培养液（补充生长因子）中培养（３８℃,５％的ＣＯ２）．结果,培养４８小时后,注射组卵裂发育率分别是：未卵裂７．９％（１１／１４０）、卵裂至２～４细胞期１１．０％（１６／１４０）、卵裂至８～１６细胞期８０．７％（１１３／１４０）．对照组相应的卵裂率分别是４．１％（６／１４５）、１２．４％（１８／１４５）和８３．４％（１２１／１４５）．两组卵裂发育率相近．本实验的显微操作对注射后卵的发育没有产生明显的伤害影响．     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.