不同激光对雨生红球藻的刺激效应

本文研究了Ｈｅ－Ｎｅ激光和半导体激光对生产虾青素的雨生红球藻（Ｈａｅｍａｔｏｃｏｃｃｕｓ ｐｌｕｖｉａｌｉｓ）的生理刺激作用。对两种激光不同辐照剂量的生长刺激作用,叶绿素含量及虾青素累积速率的变化进行了比较。实验结果表明,低功率的红色激光对红球藻营养细胞的增殖具有明显的促进作用。     

倍频Nd：YAG激光对钝项螺旋藻的诱变效应

利用倍频Ｎｄ：ＹＡＧ激光（波长５３２ｎｍ,功率５００ｍＷ,功率密度１６０ｍＷ／ｃｍ＾２）诱变钝项螺旋藻,辐照时间为１５ｍｉｎ、１０ｍｉｎ、５ｍｉｎ通过测定藻丝形态参数、叶绿素α、β－胡萝卜素、生长速度,比较倍频Ｎｄ：ＹＡＧ激光对钝项螺旋藻生长的影响。实验结果表明：与出发株相比,经倍频Ｎｄ：ＹＡＧ激光辐照后,藻丝形态发生变化,藻丝长、螺旋数、螺旋长变小;１５ｍｉｎ,１０ｍｉｎ辐照组出现螺旋变松驰;１     

Nd:YAP激光辐照对雨生红球藻生理效应的荧光分析

目的：Nd：YAP激光辐照对雨生红球藻生理效应的荧光分析j方法：利用Nd：YAG激光（功率10W,辐照剂量为15s、35s、55s）辐照雨生红球藻,在对辐照细胞进行生长测定以及色素吸收光谱分析的基础上,进一步利用激光共聚焦扫描显微镜（LSCM）,在波长488nm的Ar^＋激发光条件下,对细胞的自体荧光以及吖啶橙染色的细胞核荧光物质进行定位定量分析,获得细胞自发荧光光谱和细胞核荧光物质的荧光光谱。结果：①低剂量的Nd：YAG激光辐照（15s左右）对藻细胞有促长作用,生长速率提高20．3％,色素吸收峰的峰值提高25．3％。较高剂量的Nd：YAG激光辐照（35s、55s）对藻细胞生长有抑制作用,并有明显的致死、致突效应。②对自体荧光的分析结果表明,与对照组相比,低剂量激光辐照组的细胞,在荧光光谱的峰型及峰值上变化不大,在682nm处均有较强的荧光发射,而高剂量激光辐照组的细胞多无明显的荧光发射。③对细胞核荧光物质的分析,雨生红球藻细胞在530nm（DNA）和640nm（RNA）处均有荧光发射峰。与对照组相比,低剂量激光辐照组的DNA荧光发射有所增强,但RNA的荧光发射则有所减弱;高剂量激光辐照组的核物质荧光发射谱,在峰型上与对照组存在差异,荧光强度也明显下降。结论：低剂量的Nd：YAP激光辐照对细胞核的DNA合成与复制有一定的刺激作用,可促进光合色素的合成并提高其对光能的吸收效率,从而增强光合活性,促进细胞的增殖与生长;高剂量激光辐照则对细胞的DNA有损伤作用,是致死率上升并发生突变的可能原因。     

低强度HeNe激光辐照人体外周血对淋巴细胞染色体影响的研究

本文通过低强度Ｈｅ－Ｎｅ激光以能量密度分别为１４．３１Ｊ／ｃｍ＾２（辐照５’）、２８．６２Ｊ／ｃｍ＾２（辐照１０）、５７．２４Ｊ／ｃｍ＾２（辐照２０）１１４．５２Ｊ／ｃｍ＾２（辐照４０）燠夫体外周血后,检测其淋染色畸变率（ＣＡ）,激光照射血样（能量密度由低到高）未照射血样ＣＡ分别平均为４．２９‰、３．９６‰、３．８１‰、３．５９０‰、４．１９‰、Ｘ＾检测无显著差异,说明低强度的Ｈｅ－Ｎｅ激光辐照人     

Nd：YAP激光的不同功率和时间组合对亚心形扁藻的影响

采用同一剂量不同功率和时间组合的Nd:YAP激光(波长1 341nm)辐照亚心形扁藻,辐照组分为8W 69 s、10 W 55 s和12 W 46 s三个组合,通过藻细胞生长速率和叶绿素含量测定研究激光对扁藻的影响.实验结果表明,即使同一照射剂量,不同的辐照时间与辐照功率的组合,辐照效果仍不相同,本实验中以辐照时间55 s,辐照功率10 W 为最佳组合.     

510.6nm激光照射对兔血管平滑肌细胞增殖的影响

本文用５１０．６ｎｍ 波长激光以功率密度１、５、１０ ｍ Ｗ／ｃｍ ２ 和能量密度２、４、６Ｊ／ｃｍ ２ 照射体外培养的兔血管平滑肌细胞（ＳＭＣ）,通过３Ｈ－ ＴｄＲ掺入率和细胞生长曲线测定细胞增殖率。结果显示,上述激光照射量均能抑制细胞增殖率,其中以１０ｍ Ｗ／ｃｍ ２ 组的作用最为显著     

盐生杜氏藻和青岛大扁藻的超低温保存

采用两步法冷冻技术超低浊保存盐生杜氏藻（Ｄｕｎａｌｉｅｌｌａ ｓａｌｉｎｕ（Ｄｕｎａｌ）Ｔｅｏｄ．）和青岛大扁藻（Ｐｌａｔｙｍｏｎａｓ ｈｅｌｇｏｌａｎｄｉｃａ Ｋｙｌｉｎ ｖａｒ．ｔｓｉｇｔａｏｅｎｓｉｓ）。当二甲基亚砚（ＤＭＳＯ）浓度分别为５％和２０％,平衡时间均为ｍｉｎ,预冻温度及保持时间分别为－４０℃,６０ｍｉｎ和－３０℃,３０ｍｉｎ;化冻后分别在０℃和到温下采用慢速稀释法去除ＤＭＳＯ时,     

自发性高血压大鼠原癌基因表达和限制性内切酶片段长度多态性分析

观察自发性高血压大鼠（ＳＨＲ）血管平滑肌细胞（ＶＳＭＣｓ）的生长曲线、ｃ－ｆｏｓ原癌基因表达和ｃ－ｆｏｓ基因酶切图谱的情况,与对照组京都维斯特大鼠（ＷＫＹ）进行对比．结果显示,在小牛血清作用下ＳＨＲ的ＶＳＭＣｓ生长速率和ｃ－ｆｏｓ原癌基因表达明显大于ＷＫＹ;ｃ－ｆｏｓ原癌基因限制性内切酶片段长度多态性（ＲＦＬＰ）分析表明,经ＢａｍＨⅠ或ＥｃｏＲⅠ酶切后的ＳＨＲ和ＷＫＹ的酶切图谱一致,同时也未发现ＳＨＲ的ｆｏｓ基因扩增现象．提示,ＶＳＭＣｓ的异常增殖和ｃ－ｆｏｓ原癌基因的表达异常与高血压的形成有关,而ｃ－ｆｏｓ原癌基因的过度表达可能是由于某些与基因转录调控有关的因素异常所致．     

自发性高血压大鼠原癌基因表达和限制性内切酶片段长度多态性分析

观察自发性高血压大鼠（ＳＨＲ）血管平滑肌细胞（ＶＳＭＣｓ）的生长曲线、ｃ－ｆｏｓ原癌基因表达和ｃ－ｆｏｓ基因酶切图谱的情况,与对照组京都维斯特大鼠（ＷＫＹ）进行对比。结果显示,在小牛血清作用下ＳＨＲ的ＶＳＭＣｓ生长速率和ｃ－ｆｏｓ原癌基因表达明显大于ＷＫＹ;ｃ－ｆｏｓ原癌基因限制性内切酶片段长度多态性（ＲＦＬＰ）分析表明,经ＢａｍＨ Ｉ或ＥｃｏＲ Ｉ酶切后的ＳＨＲ－ＷＫＹ的酶切图谱一致,同时也未发     

细胞外钙调素诱导番茄县浮细胞rbcS—3A基因表达

利用番茄（Ｌｙｃｏｐｅｒｓｉｃｕｍ ｅｓｃｕｌｅｎｔｕｍ Ｍｉｌｌ．）县浮培养细胞为材料,以＾３２Ｐ标记的寡核苷酸（４０ｂｐ）为探针检测了细胞外钙调素对番茄细胞ｒｂｃＳ－３Ａ及ｒｂｃＳ－３Ｃ基因表达的影响。当向暗中培养的番茄悬浮细胞（第７天）中加入外源纯化钙调素（１０＾－７ｍｏｌ／Ｌ）并处理２４ｈ后,ｒｂｃＢ－３Ａ基因的表达明显增加,而相同深度的Ｓ－１００蛋白和ＢＳＡ则没有作用。加入外源钙调素（１     

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.