长白松人工林生态系统营养元素的分配格局和积累规律

对长白松人工林生态系统营养元素的分配格局和积累规律研究表明,乔木层不同器官营养元素含量为叶＞枝＞根＞干皮＞干材;同化器官──针叶中养分含量为Ｎ＞Ｋ＞Ｃａ＞Ｐ＞Ｍｇ;吸收器官──根中养分含量为Ｃａ＞Ｎ＞Ｋ＞Ｐ＞Ｍｇ;人工林生态系统中的养分含量为土壤＞凋落层＞草本层＞灌木层＞乔木层,乔木层养分贮量和积累率分别为８８．７９％和７６．４３％;长白松林生态系统中植物对Ｎ、Ｐ的吸收较强烈．     

紫叶酢浆草的组织培养

1　植物名称　紫叶酢浆草 (Ｏｘａｌｉｓｖｉｏｌａｃｅａ)。2　材料类别　叶片、叶柄。3　培养条件　培养基有 :( 1 )ＭＳ ＮＡＡ 0 .5ｍｇ·Ｌ- 1 (单位下同 ) ;( 2 )ＭＳ ＩＢＡ 1 .0 ＮＡＡ 0 .5 ;( 3)ＭＳ ＩＢＡ 1 .0 ＮＡＡ 0 .5 ＫＴ 1 .0 ;( 4 )ＭＳ ＩＢＡ 0 .5 ＮＡＡ 0 .5 ＫＴ 1 .0。以上培养基含蔗糖 2 5 ｇ·Ｌ- 1 、琼脂 0 .5 %,ｐＨ 5 .8。培养温度为 2 2～ 2 5℃ ,照光 1 2ｈ·ｄ- 1 ,光照度为 2 0 0 0ｌｘ。4　生长与分化情况4.1　叶柄的分化情况　取盆栽紫叶酢浆草叶片与叶柄 ,流水洗净 ,用 70 %酒精浸洗 30ｓ…     

社鼠核型的研究

社鼠核型的研究ＫＡＲＹＯＴＹＰＥＳＯＦＮＩＶＩＶＥＮＴＥＲＣＯＮＦＵＣＩＡＮＵＳ（ＲＯＤＥＮＴＩＡ：ＭＵＲＩＤＡＥ）关键词核型Ｃ带Ｇ带ＡｇＮＯＲｓ社鼠ＫｅｙｗｏｒｄｓＫａｒｙｏｔｙｐｅ,Ｃｂａｎｄｉｎｇ,Ｇｂａｎｄｉｎｇ,ＡｇＮＯＲＳ,Ｎ...     

达乌尔黄鼠染色体银染核仁组织者分析

达乌尔黄鼠染色体银染核仁组织者分析ＡＮＡＬＹＳＩＳＯＮＣＨＲＯＭＯＳＯＭＥＳＡｇ－ＮＯＲＳＯＦＣＩＴＥＬＬＵＳＤＡＵＲＩＣＵＳＫｅｙｗｏｒｄｓＣｉｌｅｌｌｕｓｄａｕｒｉｃｕｓ;Ｃｈｒｏｍｏｓｏｍｅ;Ａｇ－ＮＯＲ达乌尔黄鼠（ｃｉｌｅｌｌｕｓｄａｕｒｉｃ...     

Cr6+污染对菱叶中矿质元素含量的影响

研究Ｃｒ＾６＋污染后菱浮水叶和沉水叶中Ｃｒ、Ｋ、Ｍｇ、Ｆｅ、Ｍｎ、Ｚｎ、Ｃｕ、Ｍｏ元素的含量,结果显示：Ｃｒ含量随培养浓度的上升而上升,Ｋ、Ｍｇ随培养浓度的上升而下降,Ｆｅ含量随培养浓度的上升而出现先上升后下降,Ｍｎ、Ｚｎ、Ｃｕ、Ｍｏ与Ｃｒ＾６＋的培养浓度无明显的相关关系。     

缙云山常绿阔叶林四川大头茶果实中矿质营养元素含量及季节动态

本文测定了缙云山常绿阔叶林中四川大头茶果实中Ｎ,Ｐ,Ｋ,Ｃａ,Ｍｇ,Ｃｕ,Ｚｎ,Ｆｅ,Ｍｎ９种矿质营养元素的含量,研究了这些元素的季节吸收特点与繁殖分配,并探讨了这些元素与某些土壤化学因素之间的关系,结果表明：四川大头茶果实在生长期内矿质营养元素含量随季节而变化,各元素平均含量顺序为：Ｎ＞Ｋ＞Ｃａ＞Ｍｇ＞Ｐ＞Ｍｎ＞Ｆｅ＞Ｚｎ＞Ｃｕ。土壤中化学因子与四川大头茶果实中常量元素含量之间的关系密切,果实中Ｎ含量受土壤中Ｎ,Ｐ,Ｋ含量的综合影响,土壤有机质最终会影响到果实中Ｎ,Ｐ,Ｋ,Ｃａ的吸收,矿质元素的果实繁殖分配量与果实净生物生产量分配之间不存在特定的比例关系。果实元素分配所占比例的大小顺序为Ｐ＞Ｎ＞Ｋ＞Ｃａ＞Ｆｅ＞Ｍｇ＞Ｍｎ＞Ｚｎ＞Ｃｕ。     

鼎湖山南亚热带常绿阔叶林植物营养元素含量分配格局研究

在鼎湖山南亚热带常绿阔叶林中,植物叶片营养元素含量为Ｎ ０．９４６％－２．５３５％,Ｐ ０．０３０－０．１２７％,Ｋ ０．６１４％－１．８３３％,Ｃａ ０．４４２％－１．９９５％,Ｍｇ ０．０２４％－０．１８８％。叶片各营养养元素间相关性较差,仅Ｐ与Ｍｇ及Ｍｇ与Ｋ之间存在显著的线性相关。叶片Ｎ元素平均含量在各层中的序列为：乔木Ⅲ〉乔木Ⅱ〉乔木Ⅰ〉灌木〉藤本〉草本;其它营养元素浓度随层次分配的规律性     

北方阔叶树木固氮与非固氮树种间营养元素含量的差异及数量化分类

研究了北方阔叶树木中固氮和非固氮树种间养分元素含量的差异及季节变化趋势．在生长旺盛期到落叶期固氮和非固氮树种叶片之间Ｎ、Ｍｇ含量始终存在明显差异;固氮树种叶片中Ｎ、Ｋ含量降低的趋势明显低于非固氮树种,所研究的其它５个元素和灰分的季节变化率即累积的趋势则高于非固氮树种．在Ｆ检验和Ｔ检验的基础上,选择Ｎ、Ｐ、Ｍｇ、Ｓｉ４个营养元素为参数进行的数量化分类,成功地区分了固氮和非固氮树种．     

趋化因子CX_3C——Fractalkine的结构与功能

趋化因子是一类结构和功能相关的多肽超家族 ,分子量为 7～ 1 5ｋＤ ,分子序列中多数有四个半胱氨酸残基 (Ｃｙｓ或Ｃ)。根据Ｎ末端两个保守Ｃｙｓ的排列方式 ,趋化因子被分为Ｃ、ＣＣ、ＣＸＣ和ＣＸ3Ｃ四个亚家族。Ｆｒａｃｔａｌｋｉｎｅ(ＦＫＮ) [1] 是ＣＸ3Ｃ亚家族的唯一成员。过去认为 ,ＦＫＮ具有趋化功能 ,参与白细胞特别是吞噬细胞和淋巴细胞的游走和活化 ,同时表现有粘附作用 ,介导细胞间粘附。近年的研究发现 ,ＦＫＮ还具有其它多种潜在功能 ,如增强细胞粘附、介导免疫损伤等。1 .ＦＫＮ的结构及其受体ＣＸ3ＣＲ1ＦＫＮ编码基因…     

花尾榛鸡食物营养的研究

采用生物化学分析技术,对花尾榛鸡Ｔｅｔｒａｓｔｅｓｂｏｎａｓｉａ ａｍｕｒｅｎｓｉｓ的年周期所吃食物营养组成进行研究。结果表明,食物中营养素粗蛋白质（Ｃ．Ｐ）和粗脂肪（Ｃ．Ｆａｔ）含量,均以５月最高（２０．４６％、１４．６５％）;粗纤维（Ｃ．Ｆｉｂ）含量９月最高（４１．４４％）;粗灰分（Ｃ．Ａ）和无氮浸出物（Ｎ．Ｆ．Ｅ）含量,各月之间差别均不明显。矿物质磷（Ｐ）、钙（Ｃａ）、钾（Ｋ）镁（Ｍｇ）、铁     

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.