B链氨端去－肽（B1）羧端去五肽（B26—30）猪胰岛素的初步晶体学研究

应用悬滴气相扩散法在含６％氯化钠和１２．５％丙酮的柠檬酸缓冲体系中,获得可供Ｘ射线结构分析用的Ｂ链氨端去－肽（Ｂ１）羧端去五肽（Ｂ２６－３０）猪胰岛素单晶体。晶体属四方晶系,空间群为Ｐ４１２２或Ｐ４３２２,晶胞参数为：ａ＝ｂ＝３６．０Ａ,ｃ＝１２０．０Ａ,α＝β＝γ＝９０度。单位晶胞中每个结晶学不对称单位含有２个ＤｅｓＢ１－ＤＰＩ分子。     

高活力胰岛素研究：B3—Lys猪胰岛素的结晶及初步晶体学分析

用化学半合成方法制备的Ｂ３—Ｌｙｓ猪胰岛素（Ｂ３ＫＰＩ）具有与天然猪胰岛素相同的体内生物活力,但其体外生物活力及受体结合活力比天然猪胰岛素高。本文报道Ｂ３ＫＰＩ的晶体生长,初步晶体学分析及衍射数据与处理。Ｂ３ＫＰＩ晶体的衍射分辨率可以达到２．１Ａ（１Ａ＝０．１ｎｍ）,空间群为Ｒ３,晶胞参数为：ａＨ＝ｂＨ＝８２．２３ＡＣＨ＝３４．１７Ａ．收集了一套２．１Ａ分辨率的衍射数据,数据完全度为８１％,Ｒｍｅｒｇｅ为２．９％。     

六倍体山羊草与普通小麦杂种F1细胞学研究

粗厚山羊草［Ａｅｇｉｌｏｐｓｃｒａｓｓａ Ｂｏｉｓｓ．（２ｎ＝ ６ｘ＝ ４２,ＤＤＤ２ Ｄ２ＭＣｒＭＣｒ）］、叙利亚山羊草［Ａｅ．ｖａｖｉｌｏｖｉｉ （Ｚｈｕｋ．）Ｃｈｅｎｎ．（２ｎ＝ ６ｘ＝ ４２, ＤＤ ＭＣｒＭＣｒＳＰ ＳＰ）］与普通小麦［Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．（２ｎ＝ ６ｘ＝ ４２, ＡＡＢＢＤＤ）］杂种Ｆ１ 植株形态大多偏向山羊草亲本。４ 个叙利亚山羊草×普通小麦和１ 个粗厚山羊草×普通小麦杂种Ｆ１ 自交结实,结实率在０．１％ —６．５％ 之间。这些种子胚乳很少,生活力较弱,播种后,只有少数种子出苗。杂种Ｆ１ ＰＭＣ减数分裂染色体配对水平较低,出现大量的单价体,二价体低于理论值,并且大多为棒形,说明两种山羊草的Ｄ组染色体已经过很大的修饰。在各杂种Ｆ１ 中还观察到少量的三价体,有些杂种还可见频率很低的四价体和五价体。以山羊草为母本的杂种Ｆ１ 染色体交叉频率优于反交。Ｆ１ 染色体分离极不正常,产生大量的多分孢子和微核。在叙利亚山羊草×冀麦３０ 号中还发现１ 株体细胞染色体为２１ 条的植株,其原因尚需进一步研究确定     

血管紧张素Ⅱ对大鼠心肌肌浆网Ca~(2+),Mg~(2+)-ATPase基因转录调节的影响

观察血管紧张素Ⅱ（ＡｎｇⅡ）对心肌肌浆网Ｃａ２＋,Ｍｇ２＋－ＡＴＰａｓｅ基因（ＳＥＲＣＡ２ａ）转录调节的影响,评价ＤＭＰ８１１对此效应的干预作用．６周龄雄性ＳＤ大鼠随机分为３组,每组６只．组１：生理盐水输注;组２：ＡｎｇⅡ输注＋ＤＭＰ８１１管饲（３ｍｇ·ｄ－１·ｋｇ－１）;组３：ＡｎｇⅡ输注（２００ｎｇ·ｍｉｎ－１·ｋｇ－１．１周后称其体重,取心脏并称重,提取心脏总ＲＮＡ后采用Ｎｏｒｔｈｅｒｎｂｌｏｔ的方法检测ＳＥＲ－ＣＡ２ａ的转录水平,采用ＲＴ－ＰＣＲ检测ＡｎｇⅡ１型受体（ＡＴ１）ｍＲＮＡ水平．实验后,组３心重（ＣＷ）、心重／体重（Ｃ／Ｂ）、ＡＴ１受体转录水平均高于组１（分别增加４．７±０．４％,４．９±０．９％和２４．７±３．５％;Ｐ＜０．０１）,而ＳＥＲＣＡ２ａ基因转录水平显著低于组１（降低２０．１±３．０％,Ｐ＜０．０１）,并且ＳＥＲＣＡ２ａｍＲＮＡ水平与ＡＴ１受体ｍＲＮＡ水平呈负相关（ｒ＝－０．７４,Ｐ＜０．０１）．ＡｎｇⅡ导致的上述改变能被ＤＭＰ８１１完全阻断．ＡｎｇⅡ通过其Ⅰ型受体的介导,诱导了ＳＥＲＣＡ２ａ的转录下调     

百合巯基蛋白酶抑制剂的纯化及部分性质研究

百合的鳞茎中含有一种对木瓜蛋白酶有强抑制作用的巯基蛋白酶抑制剂．百合的鳞茎经浸取加热处理,木瓜蛋白酶偶联的Ｓｅｐｈａｒｏｓｅ４Ｂ柱亲和层析和ＳｅｐｈａｄｅｘＧ－１００分子筛层析,可获得在ＰＡＧＥ和ＳＤＳ－ＰＡＧＥ均为单一蛋白带的百合巯基蛋白酶抑制剂（ＣＰＩ）．此ＣＰＩ为单链蛋白,含有０．３０７％的中性糖;Ｎ端氨基酸为Ｉｌｅ;ＳＤＳ－ＰＡＧＥ测得亚基分子量为１２０００;ＳｅｐｈａｄｅｘＧ－１００测得分子量为１２５００．百合ＣＰＩ在１００℃内和ｐＨ２～１２范围内非常稳定;对木瓜蛋白酶的抑制属竞争性抑制类型,其Ｋｉ值为１．１５×１０~（－９）ｍｏｌ／Ｌ,对木瓜蛋白酶的抑制摩尔比为８．５：１．     

发育和早萌中花生胚胚轴一子叶内BAPAase活性的差异

花生胚发育过程中,子叶和胚轴中都出现ＢＡＰＡａｓｅ活性,花生种子明发时,子叶和胚轴中的ＢＡＰＡａｓｅ活性迅速上升,子叶中无新的ＢＡＰＡａｓｅ合成,胚轴中能重新合成ＢＡＰＡａｓｅ。ＡＢＡ抑制子叶和胚轴中ＢＡＰＡａｓｅ的活性,抑制胚轴中ＢＡＰＡａｓｅ活性所需的外源ＡＢＡ浓度更高,Ａｃｔ＝Ｄ和ＣＨＭ不能逆ＡＢＡ对ＢＡＰＡａｓｅ活性的抑制作用。     

高活力纤维素酶菌株康氏木霉B—7的选育与产酶条件的研究

野生型康氏木霉８５４－Ｂ＿２分别经物理化学诱变因子,ＴＤＰ辐射器和空间微重力辐射等因素的多级处理,得到１株形态发生明显改变的变异株Ｂ—７,其固体培养物的纤维素酶各组分酶活力,如滤纸糖酶活力（ＦＰＡ）为３４ｕ／ｇ,羧甲基纤维素酶活力（ＣＭＣ—ａｓｅ）为２９．０ｕ／ｇ,β－葡萄糖苷酶活力（β－Ｇｌａｓｅ）为２９．０ｕ／ｇ,与８５４－β２相比,分别提高５．９倍,７．６倍和４．２倍。其固体培养的最佳条件是：ｐＨ６．０,２８～３０℃,９６小时,最适培养基成分为：青草粉：麸皮＝７：３,１．５～２．０倍水和（ＮＨ４）２ＳＯ４１．５～２．０％（均以固体料计）。     

HBsAg携带者重叠感染HCV、HDV的血清学调查

对３６２名无症状高滴度ＨＢｓＡｇ携带者用ＲＩＡ法检测ＨＢｅＡｇ、Ａｎｔｉ－ＨＢｅ、Ａｎｔｉ－ＨＣＶ、Ａｎｔｉ－ＨＤＶ。结果表明,ＨＢｅＡｇ阳性率随ＨＢｓＡｇ滴度的增高而增加,且有显著性差异（Ｐ＜０．０５）。重叠感染以ＨＢＶ＋ＨＣＶ最高,占２７．６％;其次是ＨＢＶ＋ＨＤＶ,占９．１％;ＨＢＶ＋ＨＣＶ＋ＨＤＶ最少,占６．４％。但是,以上重叠感染率均与ＨＢｓＡｇ滴度及／或ＨＢｅＡｇ阳性率高低无关（Ｐ＞０．０５）。调查显示,无症状ＨＢｓＡｇ携带者中ＨＢＶ＋ＨＣＶ,或ＨＢＶ＋ＨＤＶ,或ＨＢＶ＋ＨＣＶ＋ＨＤＶ的重叠感染均可发生。     

地衣芽孢杆菌β—甘露聚糖酶的纯化及其性质的研究

地衣芽孢杆菌１Ｂａｃｉｕｕｓ Ｌｉｃｈｅｎｉｆｏｒｍｉｓ）ＢＬ－３０６产生的胞外β－甘露聚糖酶经硫酸铵分级盐析,ＤＥＡＥ－纤维素柱层析。Ｓｅｐｈａｄｅｘ－Ｇ１００柱凝胶过滤和ＤＥＡＥ－纤维素柱再层析分离纯化,得到ＳＤＳ－聚丙烯酰胺凝胶电泳（ＳＤＳ－ＰＡＧＥ）均一样品。用ＳＤＳ－ＰＡＧＥ测得纯化后β－甘露聚糖酶分子量为２６０００道尔顿。用凝胶等电聚焦电泳（ＰＡＧＥＩＥＦ）测得等电点ＰＩ为５．０。该酶     

安西荒漠植物群落和优势种的分布与环境的关系

应用排序（ＤＣＡ）和回归分析方法对安西砾石戈壁荒漠植物群落及优势种的分布与环境的关系进行了研究。结果表明,该区群落的盖度（Ｃ）和密度（Ｄ）均与年降水量（Ｒ）有密切关系,而群落的种类丰富度（Ｎ）则与土壤含盐量（Ｓ）相关,其回归关系式为：Ｃ＝０．０５１９６８１６３ｅ０．０４０７８６８２１Ｒ（Ｒ＝０．９５,Ｐ＜０．０１）,Ｄ＝０．２７１４７９１３ｅ０．０５２７４１８２９Ｒ（Ｒ＝０．９６,Ｐ＜０．０１）,Ｎ＝１３．７７４８－６．４７７３０３ｌｇ１０００Ｓ（Ｒ＝０．８３,Ｐ＜０．０１）。即：年降水量是决定戈壁荒漠植物群落盖度和密度的主要因素,土壤含盐量则与群落种类丰富度的关系尤为突出。优势种的抗旱性顺序是：红砂（Ｒｅａｕｍｕｒｉａｓｏｎｇｏｒｉｃａ（（Ｐａｌ．）Ｍａｘｉｍ．）＞泡泡刺（ＮｉｔｒａｒｉａｓｐｈａｅｒｏｃａｒｐａＭａｘｉｍ．）＞黑柴（ＳｙｍｐｅｇｍａｒｅｇｅｌｉＢｇｅ．）＞珍珠（ＳａｌｓｏｌａｐａｓｅｒｉｎａＢｇｅ．）＞膜果麻黄（ＥｐｈｅｄｒａｐｒｚｅｗａｌｓｋｉＳｔａｐｆ．）,而耐盐性顺序是：珍珠＞红砂＞黑柴＞泡泡刺＞膜果麻黄     

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.