云南西双版纳兰科十新种

1.豹斑石豆兰 新种 图1:5—6Bulbophyllum colomaculosum Tsi et S. C. Chen, sp. nov.Species nova B. obrieniano Rolfe proxima, a quo differt petalis margine dentatis.Herba epiphytica. pseudobulbi aggregati ovati, ca. 4 cm longi, medio 1.5—1.8 cm lati,     

中国石斛属一新种

Dendrobium fanjingshanense Z. H. Tsi ex X. H. Jin et Y. W. Zhang, sp. nov. Fig. 1 Habitu D. wilsonii Rolfe simile, a quo tepalis revolutis fulvis, lobo labelli intermedii infra medium macula una flabellata purpurea ornato. Epiphyticum; caulis teres, 20～40 cm altus, 2～3 mm crassus, caespitosus, superne 5～6-foliatus, internodiis 1～1.5 cm longis. Folia oblongo-lanceolata, subcoriacea, 2～5 cm longa, 5～15 mm lata, apice obtusa et plus minusve hamata, basi vaginis tubulatis membranaceis obtecta. Inflorescentiae e lateribus partium superarum caulium annotinorum defoliatorum nascentes, versus apicem caulis laterales, 1～2-florae; pedunculi 2～3 mm longi, ca. 1 mm crassi, basi vaginis 3～4 membranaceis 3～4 mm longis instructi; bracteae ovato-triangulatae, 3～5 mm longae, apice acutae, macula atro-fusca ornatae. Flores patentes; pedicelli cum ovario ca. 2～3 cm longi; tepala revoluta, fulva, apice obtusa; sepalum intermedium oblongum 2 cm longum, medio 6～7 mm latum, apice fere obtusum; sepala lateralia paulo oblique ovato-lanceolata, sepalo intermedio aequilonga sed medio paulo angustiora, apice obtusa, basi cum pede columnae mentum obconoideum ca. 8 mm longum 6 mm latum apice obtusum formantia; petala subelliptica, ca. 2 cm longa, medio 6 mm lata, apice subobtusa; labellum fulvum, basi purpureum et dense velutinum, obscure trilobatum, lobis lateralibus semiorbiculatis erectis, basi (inter lobos laterales) callo uno purpureo praeditis, lobo intermedio ovato, ca. 1 cm longo, 7 mm lato, apice subacuto et recurvo, supra medio carinato, glabro; columna alba, ca. 3 mm longa, basi in pedem ca. 9 mm longum producta, pede medio purpurato, glabro; operculum antherae album, ambitu rhombicum, glabrum; pollinia 4.     

南黄海潮汐锋对浮游细菌生物量分布的影响

2 0 0 1年 5月 16～ 2 3日、6月 10～ 2 4日和 2 0 0 2年 6月 5～ 12日 ,利用“北斗号”船只对南黄海鱼产卵场进行了 3次专项调查。研究了潮汐锋断面叶绿素 a浓度、浮游细菌生物量的分布 ,目的是阐明潮汐锋的存在对浮游细菌生物量分布的影响。3个航次中的叶绿素 a浓度变化范围分别是 0 .0 6～ 2 .34mg/ m3(2 0 0 1- 0 5 )、0 .0 8～ 0 .9mg/ m3(2 0 0 1- 0 6 )、0 .14～ 3.0 4 mg/ m3(2 0 0 2 - 0 6 )。 3航次的聚球藻 (Synechococcus spp.)蓝细菌生物量变化范围分别为 7.6 2～ 2 2 .0 6 mg C/ m3(2 0 0 1- 0 5 )、8.5 3～2 7.5 2 mg C/ m3(2 0 0 1- 0 6 )、0 .6 9～ 5 5 .90 m g C/ m3(2 0 0 1- 0 6 )。异养细菌生物量变化范围分别为 7.5 6～ 5 1.82 mg C/ m3(2 0 0 1-0 5 )、8.5 4～ 2 4 .77mg C/ m3(2 0 0 1- 0 6 )、3.12～ 10 .0 5 mg C/ m3(2 0 0 2 - 0 6 )。而聚球藻蓝细菌对浮游植物总生物量的贡献 (CB:PB)平均值分别为 :5 8% (2 0 0 1- 0 5 )、77% (2 0 0 1- 0 6 )、31% (2 0 0 2 - 0 6 )。结果表明 :南黄海鱼产卵场在春末夏初 (5～ 6月份 ) ,叶绿素 a浓度最大值及次大值主要分布在锋区及其邻近的层化区2 0 m以浅位置 ;聚球藻蓝细菌生物量最大值主要分布于锋区及层化区表层和水体中层 ;异养     

白桦愈伤组织的高效诱导和不定芽分化

选出白桦愈伤组织诱导的最适培养基为 :IS 6 BA 5 .0mg·L-1 KT 0 .5mg·L -1(茎段 ,叶柄 ) ;IS 6 BA 2 .0mg·L-1 NAA 0 .2mg·L-1(叶片 )。分化培养基为 :IS 6 BA 0 .4～ 0 .5mg·L-1,蔗糖浓度 2 0 g·L-1。愈伤组织诱导率和不定芽分化率分别达到 73 %和 90 %以上。     

大孔吸附树脂提取7-木糖-10-去乙酰紫杉醇酶解产物10-去乙酰紫杉醇

本研究利用大孔树脂富集7-木糖10-去乙酰紫杉醇的酶解产物10-去乙酰紫杉醇.首先以10-去乙酰紫杉醇(10-DAT)绝对含量为指标,通过HPLC测定比较HP20、XAD4、XAD16、XAD1600四种大孔树脂对10-去乙酰紫杉醇的吸附与解吸性能力,筛选出最佳树脂XAD1600进行实验.最佳的吸附解吸条件为:树脂柱高径比10:1,吸附流速20 mL/min,吸附量23.85 mg/mL,以6倍柱床体积的90%乙醇为洗脱液,洗脱流速20 mL/min.经XAD1600型树脂富集后10-去乙酰紫杉醇回收率达96.5%,含量20.5%.且树脂柱重复使用3次后,其吸附能力仅降低5%.     

贺兰山嵩草属一新种

贺兰山嵩草新种图1 Kobresia helanshanica W.Z.Di et M.J.Zhong, sp. nov. Species K. minshanicae Wang et Tang ex Y.C.Yang affinis, sed nuculis obovatis ca. 2.5mm. longis plano-convexis vel biconvexis non rostratis, stigmatis 2 differt. Herba perennis, 17-22cm, alta. Rhizoma breve lignosa. culmi dense caespitosi erecti obtuse triangulares ca. 1mm. diam..Folia linearia culmis breviora , 8-15cm. longa , 1-2.5 mm, lata plana , margine costaque scabra. Inflorescentia terminalis     

用高效液相色谱法(HPLC)测定肌苷中有关物质和降解产物

用HPLC测定肌苷中有关物质和降解产物 ,与主药有良好的分离效果。色谱柱为HypersilC1 8(2 5 0mm× 4 .6mm ,5 μm) ,流动相甲醇 -水 (甲醇与水体积比为 10∶90 ) ,流速 1mL·min- 1 ,检测波长 2 4 8nm。     

单引物预掺入PCR与抗体可变区基因的体外放大

用针对引导序列的5′-引物和针对恒定区的3′-引物,常规PCR程序只使所选5株单抗10个可变区cDNA中的4个得到放大.新设计的程序增设了一个反应时相:94℃ 1 min,37℃ 6-8min,循环1-3次,只加入5′-引物,补充3′-引物后,转入常规PCR循环,10个可变区cDNA均获放大.此程序被命名为“单引物预掺入PCR”.     

LPC对缺血心肌起搏离子流的影响及ISO的效应

目的:观察在缺血条件下,溶血磷脂酰胆碱(LPC)对心肌起搏离子流(If)的影响以及能否被异丙肾上腺素(ISO)逆转.方法:采用双微电极电压钳制术,在各钳制电位测定并比较缺血心肌加入LPC和LPC加ISO的起搏离子流(If)幅值.结果:缺血降低If幅值,在模拟缺血液中加入LPC 2×10-5mol/L,If幅值在Ec -80～-120 mV水平进一步显著降低(n=5,P<0.05),加重了缺血对If离子流的抑制作用.在模拟缺血液中同时加入LPC 2×10-5mol/L和ISO 1×10-6mol/L,If幅值在Ec -90～-120 mV水平比模拟缺血时有显著增加(n=8,P<0.05),但未能达到缺血前基础水平.结论: 急性心肌缺血时,毒性代谢产物 LPC 加重起搏离子流的受抑程度,即使局部儿茶酚胺大量释放和积聚,也不能完全逆转上述抑制效应.     

琥珀酸对大鼠海马CAI区神经元电压依赖性钙电流的影响

目的:观察不同浓度的琥珀酸对大鼠海马CAI区神经元电压依赖性钙通道(voltage-dependent calcium channels,VDCC)流的作用,初步探讨琥珀酸对神经元保护的电生理学基础.方法:采用传统全细胞膜片钳技术和制霉菌素(nystatin)穿孔膜片钳技术观察琥珀酸对海马CAI区神经元VDCC电流的影响.结果:不同浓度的琉角酸(10-6、10-5、10-4、10-3、10-2和10-1mol·L-1)在海马CAI区对低电压激活(low-voltage activated,LVA)钙通道电流未见任何影响,而对高电压激活(high-voltage activated,HVA)钙通道电流的抑制呈浓度依赖性.对照组HVA钙电流为580.051±7.32pA,分别给予10-6、10-5、10-4、10-3、10-2和10-1 mol·L-1的琥珀酸后HVA钙电流依次为563.74±16.65,517.99±15.24,444.66±13.26,405.32±19.11,269.03±9.96和86.41±3.25pA,同对照组相比差异有统计学意义(n=8,P<0.01).结论:琥珀酸能浓度依赖性地抑制HVA钙电流,而对LVA钙电流无影响.由此推测琥珀酸可能通过抑制HVA钙电流减少Ca2+内流而影响海马CAI区神经元的兴奋性,从而抑制癫痫的形成,其脑保护作用可能与此有关.     

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.