猪卵母细胞体外成熟与冷冻附睾精子的体外受精

由屠宰母猪卵巢分离得到505枚卵母细胞,经成熟培养,其中468枚卵丘细胞扩张,成熟率为92.7％。采用冷冻的附睾精子授精,受精率为41.9％(57/136),其中单精受精率36.8％(50/136),多精受精率5.1％(7/136)。授精卵体外培养24和48小时后的卵裂率分别为5.3％(15/258)和12.9％(30/232)。把35枚早卵裂期胚胎和250枚未见卵裂的1-细胞期受精卵移入4头受体母猪的输卵管内,其中2头妊娠,分别于1990年4月10日和29日正常分娩,共生产仔猪21头。     

有无卵丘细胞对猪GV期卵母细胞玻璃化冷冻的影响

本研究探讨卵丘细胞对猪GV期卵母细胞玻璃化冷冻效果的影响。根据卵丘细胞层数将体外收集的猪卵母细胞分成对照组、A组(3层以上卵丘细胞)、B组(2~3层以上卵丘细胞)、C组(裸卵),研究卵母细胞玻璃化冷冻后的存活率、成熟率和孤雌激活后发育潜能的变化。结果表明:玻璃化冷冻后B组和A组的卵母细胞存活率显著高于C组(p0.01);冻融后的卵母细胞在成熟率方面的表现为:A、B、C三组的成熟率分别为22.17%、27.2%和18.15%,其中B组的成熟率显著高于C组(p0.05),但均明显低于对照组(p0.01)。通过进一步的孤雌激活发现,冻融后卵母细胞的卵裂率、4~8细胞卵裂率和囊胚率在3组中均无显著性差异(p0.05),均显著低于对照组(p0.01),但B组与其中两组相比具有上升趋势。综上所述,玻璃化冷冻时保留部分卵丘细胞可以降低冷冻对猪GV期卵母细胞造成的损伤。     

小鼠精子注入兔卵母细胞受精研究

利用显微操作仪将小鼠精子注入家兔卵母细胞的胞质内和透明带下,对鼠兔异种精卵互作和异种受精胚胎的发育进行了研究,并对注射精子的数量及卵的体外成熟时间等影响鼠兔异种显微受精的因素进行了探讨,结果如下:(1)将小鼠精子分别注入兔卵胞质内和透明带下,均能激活兔卵母细胞,导致精核解聚和原核形成;(2)小鼠精子注入兔卵胞质内和透明带下受精,杂种胚胎体外培养能发育到8-细胞期;(3)鼠兔异种受精4-细胞胚胎染色体标本制备观察结果表明,它们为正常二倍体;(4)鼠兔异种受精4-细胞胚胎的超微结构观察结果表明,它们极近似兔正常4-细胞胚胎的超微结构;(5)将小鼠精子注入兔卵透明带下,注射5—10个精子组卵的受精率(32.4%)和卵裂率(16.2%)均高于注射单个精子组的,但二组间差异不显著(P>0.05);DM 15%NCS液中体外成熟培养11—12h兔卵透明带下注入1—2个小鼠精子后的受精率(42.3%)和卵裂率(30.8%)均高于体外成熟培养24—25h组的,但二组间差异未达到显著水平(P>0.05)。     

小鼠不同阶段胚胎玻璃化冷冻保存的比较研究

采用玻璃化冷冻法对ICR、C57BL/6、DBA~*C57BL/6杂交F1代三种品系小鼠的不同阶段胚胎进行冷冻保存,比较胚胎解冻后形态良好率、体外发育率和移植后的出生率,结果表明解冻后各品系小鼠胚胎从2细胞到桑椹胚形态良好率在75%以上,其中8细胞胚胎形态良好率在83%以上,而囊胚的形态良好率仅在40%左右。解冻后胚胎体外培养的发育率随胚胎发育阶段的提高而提高,桑椹胚的发育达93%以上。体外受精2细胞冷冻胚与体内受精2细胞冷冻胚比较,二者形态良好率差异无显著意义(74%∶75%),但体内受精冷冻胚的发育率明显高于体外受精冷冻胚(76%:40%,p<0.01);胚胎经过三次反复冻融后形态良好率无显著差别;冷冻2细胞胚移植后的受孕率与仔鼠出生率分别达64%和40%,但均低于新鲜2细胞胚。     

应用乙二醇冷冻小鼠胚胎：优化和简化程序的探索

提高解冻胚胎的发育能力和简化冷冻解冻程序是胚胎冷冻研究的两大永恒的主题。尽管乙二醇（EG）广泛用于家畜胚胎冷冻,但很少用于冷冻小鼠和人胚胎。为数很少的以EG慢冻小鼠或人胚胎的研究均采用较为复杂的人胚冷冻程序,未见简化程序和用EG冷冻小鼠桑椹胚的报道。采用简单的牛胚胎冷冻程序研究了发育时期、EG浓度、平衡方法、添加蔗糖以及解冻后脱除EG等对小鼠胚胎冻后发育能力的影响。结果显示：（1）致密晚期桑椹胚冻后体外培养囊胚发育率（81.92%±2.24%）和孵出率（68.56％±2.43%）显著（P＜0.05)高于4-细胞、8-细胞胚胎和致密早期桑椹胚胎;（2）1.8mol/L EG冷冻小鼠致密晚期桑椹胚的囊胚发育和孵出率显著高于其它浓度;（3）在EG中平衡10min的冻后囊胚发育显著好于平衡5、20或30min;（4）两步平衡冷冻胚胎的囊胚发育率和孵出率显著高于一步平衡;（5）用EG冷冻小鼠胚胎无需添加蔗糖;（6）解冻后可不脱除EG;（7）冻后发育的早期囊胚和囊胚细胞数明显少于体内发育胚胎。因此,用EG冷冻小鼠胚胎的最佳方案为：致密晚期桑椹胚用1.8mol/L EG不添加蔗糖、两步平衡15min、以简单的牛胚胎冷冻程序冷冻解冻、解冻后不脱除EG直接培养或移植。     

小鼠卵母细胞体外成熟、体外受精的效果观察

目的　研究不同培养条件对小鼠卵母细胞体外成熟及体外受精率的影响。方法　小鼠卵母细胞分别在含有FSH、BSA和胰岛素的培养液中体外成熟,在Whitten 氏液中体外受精,比较体外成熟率、体外受精率。结果　1- 裸卵(DO) 的体外成熟率、体外受精率(81-4% ,31-0 % ) 均高于卵丘卵母细胞复合体(COC)(48-6 % ,27-1% ) 。2- 在培养液中添加FSH、胰岛素和BSA,卵母细胞的体外成熟率为77-9 % ,82-3% 、60-7% ;体外受精率为77-2 % 、72-6 % 、26-7% ;2 - 细胞率为49-2 % 、34-2 % 、10-0% 。胰岛素组的卵母细胞IVM 率最高,但IVF率、2 - 细胞率低于FSH 组。3- 添加BSA的两组的体外受精率只有26-7 % 、25-8 % ,显著低于其他组,其体外成熟率也较添加FSH 和胰岛素的组成。4- 排出第一极体(PbI) 的卵母细胞的体外受精率和2 - 细胞率(85-9 % ,22-4% ) 均高于GV期卵母细胞(71-1 % ,12-9 % ) 。结论　1- 卵丘卵母细胞(COC) 较裸卵(DO) 的体外成熟率、体外受精率都低,差异显著(P成熟< 0-01;P受精< 0-05) 。2-FSH 和胰岛素均能提高小鼠卵母细胞的体外成熟率、体外受精率。3-BSA可以降低小鼠卵母细胞体外受精率,差异极显著。4-GV 期卵母细胞的体外受精率显著低于体外培养的排出第一极体的卵母细胞(P2 - cell < 0-05,P受精<0-05)     

原癌基因c-myb在体外孕酮诱导小鼠卵母细胞成熟中的作用

目的：本文采用体外培养技术观察原癌基因c-myb对孕酮诱导的生发泡（GV）期小鼠裸卵体外成熟的影响。方法：建立小鼠裸卵体外培养模型,用不同浓度反义C-myb寡脱氧核苷酸（c-myb ASODNs）与GV期小鼠裸卵共孵育观察其对孕酮诱导的小鼠裸卵体外成熟的影响并探讨其机制。结果：在M199培养液中体外培养GV期小鼠裸卵24h,10μmol／L孕酮组与5μmol／L孕酮组比较有显著性差别（2 h GVBD％ P〈0.05,8 h PBI％ P〈0.05）．与20μmol／L孕酮组比较无显著性差别。10μmol／L c-myb AFODNs能抑制孕酮（10μmol／L）诱导的小鼠裸卵体外成熟（2 h GVBD％ P〈0.05,8 h PBI％ P〈0.01）。1×10^-4μmol／L dbcAMP、10μg／ml肝素钠可分别单独抑制孕酮诱导的GV期小鼠卵母细胞体外成熟（2 h GVBD％均P〈0.01,8 h PBI％均P〈0.01）．也可和反义c-myb ODN协同抑制孕酮诱导的卵母细胞体外成熟（2 h GVBD％均P〈0.01,8 h PBI％均P〈0.01）。结论：孕酮、原癌基因c-myb和cAMP、Ca^2＋参与了GV期小鼠卵母细胞的体外成熟,孕酮、cAMP和Ca^2＋调控卵母细胞成熟的机理可能与原癌基因c-myb表达有关。     

绵羊卵母细胞的体外培养、受精与发育的观察

笔者等把屠宰母羊卵巢卵母细胞经体外培养成熟后用于体外受精,曾得到76.2—92.5％的受精率。本实验将体外成熟、受精后的羊卵在体外条件下继续培养或者在2—4细胞期移植给受体母羊之后,分别观察了培养卵的发育情况和移植羊的受胎率。     

自制载体冷冻小鼠原核期胚胎效果分析

目的探讨自制冷冻载体冷冻保存昆明小鼠体内原核期胚胎的可行性。方法首先,比较了两种流行的商业化载体:开放式拉长麦管(open pulled straw,OPS)和冷冻帽(cryotop)开展小鼠原核胚玻璃化冷冻保存效果。其次,以cryotop为对照,利用自制简易载体(cryotip)开展小鼠原核期胚胎的玻璃化冷冻保存。之后,利用ANOVA对各组胚胎在复苏后的体外培养卵裂率、囊胚率进行统计分析。结果 OPS和cryotop两组之间,胚胎在玻璃化冷冻/复苏后发育的2-细胞率、4-细胞率和囊胚率差异均无显著性(P0.05),但cryotop冷冻效果更接近对照组;cryotip玻璃化冷冻载体与cryotop相比,胚胎复苏后各组差异均无显著性(P0.05),数值上除了2-细胞发育率外,cryotip其他几项结果都稍微高于cryotop组。结论 OPS,cryotop,cryotip冷冻保存昆明小鼠体内原核期胚胎均是可行的;cryotop在冷冻效果上要优于OPS,笔者自制的cryotip因其成本低,制作简单,操作安全可靠,在实验中替代昂贵的商业化载体OPS和cryotop是可行的。     

牛卵母细胞玻璃化冷冻对基因mRNA表达量的影响

目的 将处于生发泡期(GV期)和体外成熟期(IVM)的牛卵母细胞进行玻璃化冷冻.解冻,对其卵裂率和囊胚率以及一些与发育相关基因的mRNA表达量进行评价.方法 玻璃化冷冻GV期(n=224)和IVM期(n=235)牛卵母细胞,解冻后对其进行体外培养并采用quantitative real time-PCR技术对冷冻.解冻...     

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.