硬粒小麦单倍体原生质体培养及植株再生

由硬粒小麦（Ｔｒｉｔｉｃｕｍ ｄｕｒｕｍ Ｄｅｓｆ．）×玉米（Ｚｅａ ｍａｙｓＬ．）建立的单倍性胚性愈伤组织,在继代培养４ 个月后置于含２．０ ｍ ｇ／Ｌ２,４－Ｄ、３％ 蔗糖、２００ ｍ ｇ／Ｌ水解酪蛋白、１４６ ｍ ｇ／Ｌ谷氨酰胺和３００ ｍ ｇ／Ｌ天冬氨酸的ＭＳ液体培养基中进行悬浮培养,４ 个月后形成了生长迅速、由大小不同（０．５ ～５ ｍ ｍ ）的愈伤组织块组成的愈伤组织悬浮系。酶解试验表明,２．０％ 纤维素酶ＲＳ和０．５％ 的离析酶效果最好,而液体悬浮培养物和固体培养的愈伤组织（在酶解时用锋利的解剖刀片切成１ ｍ ｍ 左右的小块）都能释放出大量原生质体,但悬浮培养物释放出的原生质体状态较好,胞质更浓厚,用ＫＭ８ｐ 培养基以琼脂糖包埋培养方式培养时分裂频率可达５％ 左右。由原生质体再生的小愈伤组织经增殖、筛选后可获得胚性愈伤组织,将其转移至分化培养基Ⅰ（０．２ ｍ ｇ／Ｌ ２,４－Ｄ、１．０ ｍ ｇ／Ｌ ＢＡＰ、０．１ ｍ ｇ／ＬＮＡＡ、３％ 蔗糖、２００ ｍ ｇ／Ｌ 水解酪蛋白、１４６ ｍ ｇ／Ｌ谷氨酰胺和３００ ｍ ｇ／Ｌ天冬氨酸的ＭＳ固体培养基）和Ⅱ（不含２,４－Ｄ,其它成分同Ⅰ）上进行分步分化培养可再生出完整植株,分化频率约为２０％     

毛花猕猴桃原生质体再生植株

从毛花猕猴桃（Ａｃｔｉｎｉｄｉａ ｅｒｉａｎｔｈａ Ｂｅｎｔｈ．）试管培养的实生苗新展开叶片分离的原生质体,培养在液体ＭＳ（除去ＮＨ４ＮＯ３）附加２,４－Ｄ １．０ ｍ ｇ／Ｌ和葡萄糖０．４ ｍ ｏｌ／Ｌ的培养基上。培养３周后植板率达到１９．４％ 。在未添加新鲜培养基的情况下,原生质体再生的细胞可持续分裂,并于３个月时长成２ ｍ ｍ 大小的愈伤组织。将该愈伤组织转移到附加玉米素０．５ ｍ ｇ／Ｌ和ＩＡＡ ０．１ ｍ ｇ／Ｌ的固体ＭＳ培养基上,分化出苗。试管苗经诱导生根,长成完整小植株     

杨树新品种叶肉原生质体培养和植株再生

从１ 个月龄的ＮＬ－８０１０６ 杨（Ｐｏｐｕｌｕｓｄｅｌｔｏｉｄｅｓ×Ｐ． ｓｉｍ ｏｎｉｉ）无菌苗叶片分离得到大量原生质体,纯化后其原生质体产量为４×１０７／ｇ ｆｒ．ｗ ｔ． 纯化的原生质体在含２,４－Ｄ ２ ｍ ｇ／Ｌ、ＮＡＡ ０．５ ｍ ｇ／Ｌ和ＫＴ ０．５ ｍ ｇ／Ｌ的ＫＭ８ｐ 和ＭＳ培养基中进行高密度液体浅层培养,渗透势为０．４０ ｍ ｏｌ／Ｌ的ＫＭ８ｐ 培养基中原生质体分裂频率最高． 培养第５ 天观察到第一次细胞分裂,培养１０ ｄ 的分裂频率为４．５％ ,１２ 周内可形成大量的细胞团和小愈伤组织． ＮＬ－８０１０６杨叶肉原生质体在富含有机氮并以葡萄糖为碳源的培养基中具有较高的分裂频率和植板率．小愈伤组织在ｇｅｌｒｉｔｅ 固化的ＮＬＺ１ 培养基上增殖生长,３ 周后形成４—６ ｍ ｍ 结构紧密的鲜红色愈伤组织,转至ＮＬＦ分化培养基,分化成苗率为１００％ ． 待芽伸长到３ ｃｍ 时,从基部切下转至１／２ ＭＳ培养基上诱导生根,形成完整植株     

大叶紫花苜蓿愈伤组织原生质体再生植株

大叶紫花苜蓿下胚轴诱导的愈伤组织在继代培养基上生长快速,易于分散。继代第１２ｄ的愈伤组织原生质体的得率为６．５×１０７／ｇ鲜重。原生质体培养基为ＳＨ基本培养基,含有１．０ｍｇ／Ｌ２,４－０、０．５ｍｇ／ＬＢＡ、２．０ｇ／ＬＣＨ、２％蔗糖、６％葡萄糖、５ｍｍｏｌ／ＬＭＥＳ,培养密度为１．０×１０５／ｍＬ。培养至第１２ｄ时的原生质体再生细胞植板率为３．７％。由原生质体形成的小愈伤组织在含２．０ｍｇ／Ｌ２,４－Ｄ的ＭＳ固体培养基上大量增殖。增殖的愈伤组织转移至２．０ｍｇ／Ｌ２－ｉｐ＋０．１ｍｇ／ＬＮＡＡ的Ｂ５培养基上,形成体细胞胚并发育成完整植株。     

苎麻原生质体培养及植株再生

用苎麻（Ｂｏｅｈｍ ｅｒｉａ ｎｉｖｅａ）子叶诱导愈伤组织并建立悬浮细胞系． 用４．５％ 纤维素酶、０．８％ 离析酶、０．８％ 半纤维素酶的混合酶液分离悬浮培养细胞,可得到２×１０６ 个／ｇ ｆｒ．ｗｔ的原生质体．这些原生质体以海藻酸钠包埋方式培养在附加２,４－Ｄ ０．５ ｍ ｇ／Ｌ、ＫＴ ０．５ ｍ ｇ／Ｌ 的ＫＭ８ｐ 培养基中,５０ ｄ 左右可形成肉眼可见的小愈伤组织．愈伤组织经过扩增,在不同的分化培养基上可诱导芽、根的形成,再生出完整植株． 子叶原生质体则仅能进行几次有限的分裂     

菜心下胚轴原生质体培养和植株再生

以萌发３—４ 天（长约４ ｃｍ ）的菜心（Ｂｒａｓｓｉｃａ ｃａｍｐｅｓｔｒｉｓ ｖａｒ．ｐａｒａｃｈｉｎｅｓｉｓ）无菌苗苍白下胚轴为材料,酶解分离原生质体。经纯化的原生质体,在含０．５ ｍ ｇ／ＬＺＴ、０．５ ｍ ｇ／Ｌ２,４－Ｄ、１．０ ｍ ｇ／ＬＮＡＡ 和０．４ ｍ ｏｌ／Ｌ葡萄糖的Ｋ８ｐ 培养基中,进行微滴培养。在起始培养１４—１８小时,原生质体再生新的细胞壁。３６ 小时再生细胞开始第一次分裂。第三天分裂细胞频率可达３５％ 。培养第８—９ 天,可见含８—１６个细胞的小细胞团,植板率为１５％ —１８％ 。３ 周后将发育成直径为２ ｍ ｍ 的白色小愈伤组织,转到含０．３ ｍ ｇ／Ｌ ２,４－Ｄ并用ｇｅｌｒｉｔｅ半固化的培养基上,增殖成４—５ ｍ ｍ 直径的愈伤组织。在ＭＳ＋ ３．２（或１．６） ｍ ｇ／Ｌ ＢＡ＋ １．６（或０．８） ｍ ｇ／ＬＺＴ＋ ０．０１ ｍ ｇ／Ｌ ＮＡＡ＋ ０．１ ｍ ｇ／ＬＧＡ３ 和０．２％ 蔗糖的分化培养基上,获得芽的分化。切下约２ ｃｍ 长的芽苗,转移到含０．２ ｍ ｇ／ＬＩＡＡ 和２％ 蔗糖的培养基上,生根形成完整植株     

马铃薯器官发生和植株再生研究

虎头、克４和Ｆａｖｏｒｉｔａ３个马铃薯品种的根、茎、叶外植体在附加ＮＡＡ和ＢＡ各１ｍｇ／Ｌ的ＭＳ培养基上诱导出愈伤组织。在附加０．２ｍｇ／ＬＮＡＡ和１ｍｇ／ＬＢＡ的ＭＳ培养荐,愈伤组织上分化产生不定芽。１．５－２．５ｃｍ高的不定芽在ＭＳ＋０．０５ｍｇ／ＬＮＡＡ培养基上生根形成再生完整植株。３个马铃薯品种中,虎头茎的愈伤组织诱导频率最高,达９８％。Ｆａｖｏｒｉｔａ叶愈伤组织的不定芽分化频率和不定芽生     

土人参原生质体培养再生植株

分别由土人参（Ｔａｌｉｎｕｍ ｐａｎｉｃｕｌａｔｕｍ （Ｊａｅｑ．） Ｇａｅｒｔｎ．）组织培养再生苗的叶片和幼茎诱导的愈伤组织游离出原生质体．叶肉原生质体在培养中未能进行正常分裂,存活不过１ 周．愈伤组织原生质体在Ｐ４ 培养基中（Ｋ８ｐ＋ ２,４－Ｄ ０．２ ｍ ｇ／Ｌ＋ ＮＡＡ １．０ ｍ ｇ／Ｌ＋ ＺＴ ０．５ ｍ ｇ／Ｌ＋椰乳５０ ｍ Ｌ／Ｌ＋ 葡萄糖０．５ ｍ ｏｌ／Ｌ）培养３ ｄ 开始第一次分裂,培养７ ｄ 时分裂频率为３６．７％ ． 愈伤组织再生率在液体培养中为０．３１％ ,在双层培养中为０．３４％ ． 愈伤组织在含有较低浓度的６－ＢＡ 的分化培养基上分化出不定芽． 幼苗生根后移栽到花盆中继续生长,２～３个月后开花结实,长出粗壮的肉质根． 再生小植株在试管中继代培养２～３ 个月开花结实． 研究结果还表明∶（１）愈伤组织在液体培养基或增殖培养基中培养时间过长,或继代次数过多均不利于分化．（２）较低浓度的６－ＢＡ （０．５～０．７ ｍ ｇ／Ｌ）对愈伤组织的分化是合适的．（３）ＧＡ３ 对幼苗的发育有促进作用． （４）多效唑（ＭＥＴ）对土人参试管苗有明显的壮苗和壮根作用     

石斛离体培养中ABA对诱导花芽形成的影响

由兰科植物铁皮石斛（Ｄｅｎｄｒｏｂｉｕｍ ｃａｎｄｉｄｕｍ Ｗａｌｌ．ｅｘ Ｌｉｎｄｌ．）种子诱导形成的愈伤组织,在光照下置于ＭＳ附加０．３ ｍ ｇ／ＬＮＡＡ 的培养基上繁殖,可以形成原球茎。将原球茎转入ＭＳ含２ ｍ ｇ／Ｌ ６－ＢＡ 和０．５ ｍ ｇ／ＬＮＡＡ 的培养基上,花芽形成频率为２７．０％ 。原球茎先在０．５ ｍ ｇ／ＬＡＢＡ的培养基上预培养１５ ｄ,再转入含２ ｍ ｇ／Ｌ６－ＢＡ 的ＭＳ培养基上培养,花芽形成频率明显提高,可达８４．４％ ,而且每株植株花的数目增加;但是在仅有ＡＢＡ 的ＭＳ培养基上培养的原球茎再生的植株未见花芽形成     

中麻黄悬浮培养体系的建立

本文用中麻黄无菌苗为外植体,其切段培养在附加２ｍｇ／Ｌ２,４－Ｄ和０．５ｍｇ／Ｌ　６　ＢＡ的ＭＳ培养基上,全部脱分化形成白色疏松愈伤组织。愈伤组织继代培养于ＭＳ＋０．５ｍｇ／Ｌ２,４－Ｄ＋０．２ｍｇ／Ｌ６ＢＡ＋０．２ｍｇ／Ｌ　ＮＡＡ＋４％蔗糖的培养某上。以继代培养愈伤组织为材料进行悬浮培养,培养基为附加０．２ｍｇ／Ｌ２,４－Ｄ＋０．１ｍｇ／Ｌ６ＢＡ＋０．１ｍｇ／ＬＮＡＡ＋２％蔗糖的ＭＳ液体培养基,得到分散性好,细胞形状接近圆形,细胞大小均一,细胞团多由２－３０个细胞组成的悬浮培养体系。第三代悬浮培养细胞增长率为０．３５ｇ·ｆｗ／２０ｍｌ·ｄ,细胞有丝分裂指数为１１．２％。条件培养和高密度接种可缩短延迟期,条件培养不能提高分裂指数,１ｇ／１０ｍｌ接种密度可使分裂指数提高至２１．２％。     

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.