奶山羊不同发育时期乳腺上皮细胞中内质网和线粒体的变化

为研究奶山羊乳腺的胚后形态发育,采用活细胞荧光标记法结合激光共聚焦显微技术,观察奶山羊乳腺发育中内质网和线粒体的变化.结果显示:腺上皮细胞内质网和线粒体在妊娠初期和中期数量较少,妊娠晚期开始逐步增加,泌乳中期达到高峰并维持在一个较高的水平上,退化期迅速下降,逐渐恢复到妊娠前状态;退化期乳腺上皮细胞内仍保持一定数量的细胞器,以维持细胞的正常机能和活动.     

女人要好好呵护自己的乳房——乳腺癌的防治

乳腺于青春期开始发育,乳房腺体由15～20个腺叶组成,腺叶分成若干个腺小叶,每一腺小叶又由数十个腺泡组成。这些腺泡紧密地排列在小乳管周围,腺泡的开口与小乳管相连。总导管又称输入管,开口于乳头。静止期乳腺是指未孕女性的乳腺,腺体不发达;     

心理应激致孕鼠乳腺发育不良及雌/孕激素和受体水平异常

目的研究心理应激对孕鼠乳腺发育的影响,评价相关激素及其受体的表达水平。方法妊娠期Wistar大鼠随机分为对照组和实验组,实验组大鼠15 d内随机施加噪音、束缚、昼夜颠倒、冰水游泳和夹尾致痛5种不可预见性应激刺激。观察大鼠乳房外观变化,测量乳头直径和高度并计算乳房系数,光密度法测定乳腺组织DNA和RNA水平,放射免疫法测定血浆和乳腺组织雌激素(E2)、孕酮(P)、生长激素(GH)及催乳素(PRL)水平,放射配基结合分析法测定雌二醇、孕酮受体的最大结合容量(Bmax)和解离常数(Kd),乳房组织H-E染色,光镜下观察组织形态变化。结果与对照组比较,实验组大鼠乳头直径和高度减小、乳房重量减轻、乳房系数减小(P0.05,P0.01),乳房组织DNA、RNA及RNA/DNA均明显减小(P0.05,P0.01),血浆E2、P和GH水平明显下降(P0.05,P0.01),组织匀浆E2和GH水平明显降低(P0.05,P0.01),E2受体和P受体Bmax明显降低、Kd均明显升高(P0.05,P0.01);乳腺小叶、小叶腺泡数目减少、腺泡直径明显降低(P0.05)。结论心理应激能导致孕鼠乳腺发育不良,引起雌、孕激素水平及其受体表达异常。     

半胱胺对鹅胰液分泌及胰酶活性的影响

目的 :研究半胱胺对鹅胰液分泌及胰酶活性的影响。方法 :12只装有胰腺～十二指肠长久性瘘管的成年鹅。试验采用自身对照 ,试验期在日粮中一次性添加半胱胺 (10 0mg/kgbw)。连续收集计量胰液并测定胰酶活性。 结果 :①半胱胺使鹅胰液的分泌速率较对照期显著上升 (2 4 0 .16 % ,P <0 .0 1) ,其中白天升高 2 34.4 5 % ,夜间增高了2 5 3.70 %。②试验期单位容积胰蛋白酶的活性较对照期升高了 4 9.0 5 % (P <0 .0 1) ,而胰脂肪酶和胰淀粉酶的活性却较对照期分别降低了 2 5 .4 4 %和 2 1.95 % ,且变化幅度具有昼夜的差别。③试验期胰腺每小时分泌胰蛋白酶、胰脂肪酶和胰淀粉酶的总活性较对照期分别升高 4 0 6 .88% (P <0 .0 1)、15 3.5 8% (P <0 .0 1)和 16 6 .5 9% (P<0 .0 1) ,白天增加的幅度较夜晚大。结论 :半胱胺能促进鹅胰液的分泌 ,增加胰液中蛋白酶、脂肪酶和淀粉酶分泌的总量 ,从而提高鹅对饲料的消化能力 ,适应机体生长对营养的需求     

光周期对三带喙库蚊发育期间体内核酸动态的影响

作者测试了长短光周期处理的三带喙库蚊Culex tritaeniornynchus(Giles)各虫态与滞育及解滞蚊体内RNA与DNA的变化.结果表明:幼虫与蛹核酸含量最高,成虫期变化比较稳定.短光周期可以降低该蚊发育期间核酸的合成作用.雌蚊卵形成期间DNA相对稳定,吸血后卵巢开始发育,RNA含量明显增加,36—48小时达到高峰,然后逐渐下降.10—15日龄的滞育蚊体内DNA比发育蚊低,解滞蚊RNA与DNA含量均比发育蚊为高.新蚊、发育、滞育与解滞蚊间DNA、RNA含量不同,DNA、RNA减少与增加可用作判断滞育发生与解除的一个生化指标.     

牦牛DBI基因的分子特征及其在乳腺组织中的表达与定位

地西泮结合抑制因子(Diazepam binding inhibitor,DBI)与酰基辅酶A具有高亲和力,在动物组织中广泛存在,与脂肪酸代谢、类固醇激素合成密切相关。为研究DBI基因的分子特征及该基因在乳腺发育中的作用,对牦牛DBI基因编码区进行克隆,进行生物信息学分析;采用实时荧光定量PCR (Quantitative real-time PCR,qPCR)、蛋白免疫印迹技术(Western blotting,WB)和免疫组织化学(Immunohistochemistry,IHC)方法对牦牛泌乳前期、泌乳期和干乳期的乳腺组织中DBI的相对表达量和表达部位进行研究。DBI序列分析显示：牦牛DBI基因编码区序列长264 bp,编码87个氨基酸残基,与牛的同源性高达99.62％;qPCR数据表明：牦牛泌乳前期乳腺组织中DBI基因的相对表达量显著高于泌乳期和干乳期(P< 0.05);WB结果显示：牦牛泌乳前期乳腺组织中DBI蛋白的表达量最高,干乳期次之,泌乳期最低(P< 0.05);IHC结果表明：不同发育时期的牦牛乳腺组织中DBI的表达部位并无明显差异,主要表达于乳腺腺泡上皮细胞、导管上皮细胞及小叶间质细胞。DBI在不同发育时期牦牛乳腺组织中的相对表达量具有明显差异(P< 0.05),揭示DBI可能参与牦牛乳腺发育的过程,这为进一步探究DBI基因在生物体中的作用提供相应的理论参考。     

杉木雌配子体与后胚发育过程中核酸、蛋白质和类脂的消长

在杉木胚胎分化期至成熟期,每个雌配子体总核酸和DNA,RNA含量在初期增加,后期则随着胚的分化发育逐渐下降,而蛋白质和类脂则一直上升。每胚总核酸、DNA,RNA则相应增加,而蛋白质、类脂的含量和干重亦逐渐增加。在胚分化早期RNA的迅速合成与细胞的分化及器官形成有关。但以胚干重为单位的DNA、RNA含量却随着胚的发育而有所减少;蛋白质含量先增加,至成熟后才下降。授粉前的胚珠,以及雌配子体、胚中都发现有凝集素存在。     

高等植物胚胎的发育生物学研究——Ⅵ.粳稻胚分化发育期间一些大分子物质的动态

鉴测了粳稻胚的发育进程及不同分化发育时期中DNA、RNA、蛋白质、淀粉含量和鲜重、干重、细胞数的变化。 开花后6～13天(胚分化第一到第四叶原基期间)胚细胞数增加时,DNA、RNA含量迅速上升。此后细胞数和DNA、RNA含量都趋于稳定,但RNA在18～25天再次增长。每胚蛋白质和干重基本上随RNA含量相应地变化。 每毫克胚于重的核酸和蛋白质含量在13天出现明显的转折。平均每细胞的DNA含量在整个发育期保持稳定,RNA第一阶段的增长只持续到分化完成的前夕,而蛋白质在25天以前一直增加。 胚内淀粉的累积在整个胚形成期呈现三段斜率不同的直线。以单位干重表示时则在8天左右和21天出现两个高峰,先于RNA和蛋白质两次积累的高峰。 在大分子物质的变化与胚胎发育进程相互关系并与籼稻比较的基础上,将稻胚发育划分为原胚期、分化期、成熟期和休止期。     

家蚕性附腺发育与核酸及利它素蛋白变化的关系

对不同发育时期家蚕Bombyx mori雌性性附腺核酸和蛋白质含量测定的结果表明, 从家蚕化蛹后第6天到成虫羽化当天的性附腺内总蛋白质含量不断增加,至羽化当天为最高,达860±70 μg/对。不同时期内能引诱野蚕黑卵蜂识别寄主的利它素在总蛋白中所占的比例差异明显,从化蛹后第6天的10%增加到羽化后的58%。性附腺的总RNA含量从化蛹第6天到成虫羽化前1天几乎是直线增加,但羽化后下降很快。不同时期分泌部中总RNA含量变化与贮存部明显不同。含量最高时,分泌部RNA可占整个性附腺RNA的90%以上,而贮存部总RNA含量则远少于分泌部,羽化当天约为分泌部的十分之一。分泌部总RNA中的18S亚基含量远高于28S亚基,明显不同于贮存部的。从分泌部总RNA中分离的mRNA存在明显的条带分布,这预示着高丰度的mRNA的存在与总蛋白中高含量利它素的存在有着特殊对应关系。     

生长抑素在大鼠乳腺组织中的分布和定位

目的研究生长抑素在大鼠乳腺组织中的分布和定位。方法本实验应用即用型快速免疫组化方法对处女期、妊娠6 d、12 d、18 d和泌乳6 d、12 d、18 d的SD大鼠的乳腺进行生长抑素检测。结果发现从处女期到泌乳期大鼠乳腺组织中均有生长抑素的表达,且主要分布于上皮细胞的胞质和腺泡的分泌物中。结论大鼠乳腺上皮细胞的胞质和腺泡的分泌物中有生长抑素的分布。     

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.     

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.