乐清湾泥蚶繁殖生态及种群数量变动

乐清湾位于浙江省瓯江口的北侧,是一个葫芦形的内湾,湾长40km,平均宽度10km,全湾有水面270km~2, 标准水面以上的滩涂约200km~2。乐清湾是我国泥蚶苗的主要产地之一,历史上年产蚶苗在3.0×10~8棵左右,1964年以前蚶苗除自给外还远销省内外,但从60年代中期开始,蚶苗数量急剧减少,到60年代末蚶苗趋于绝迹,每年只得从山东引进蚶苗进行养殖,严重影响了泥蚶养殖事业的发展。为了尽快恢复乐清湾的蚶苗资源,浙江省海洋水产养殖研究所于1981—1985年进行了“乐清湾泥蚶自然增殖研究”,围绕乐清湾泥蚶     

绢丝丽蚌年龄与生长的研究

绢丝丽蚌一年生长一个生长轮。年轮可肉眼观察贝壳外表面凹陷的生长轮来鉴定,用纵剖贝壳明暗相间层数与打磨后观察棱柱层和珍珠层上的生长轮来验证。绢丝丽蚌10龄以前生长较快,10龄以后生长逐渐减慢。10龄以前年龄(A)与壳长(L)呈直线相关,年龄与壳重(Ws)、体重(W)均呈幂函数相关,其10龄以前的方程式分别为：L=0．8980A 0．8600(r=0．9883),Ws=1．0175A^2.3399(r=0．9997),W=1．3188A^2.3333=0．9997)。10龄以后年龄与壳长、壳重和体重均呈直线相关,其回归方程式分别为：L=0．1817A 7．9085(r=0．9813),Ws=10．7720A 61．1930(r=0．9902),W=13．6960A 78．8690(r=0．9903)。壳长与壳重、体重之间均呈幂函数相关,其相关方程式分别为：Ws=0．6303L^2.4846(r=0．9999),W=0．8181L^2.4775(r=0．9999)。壳重与体重之间呈线性相关,其回归方程式为：W=0．3560 1．2744Ws(r=0．9999)。     

稻田养殖铜锈环棱螺繁殖与仔螺生长特性

为阐明稻田养殖模式下铜锈环棱螺的繁殖特点及仔螺的生长规律, 于2019年5—11月对稻田养殖的铜锈环棱螺进行逐月采样分析。研究结果表明, 稻田养殖铜锈环棱螺的产仔高峰期为6月, 仔螺的产出规律为2个月1个周期。最小繁殖体重为0.9 g, 最小繁殖月龄为2月龄。不同体重规格的性成熟雌螺, 其怀胚量与体重呈显著正相关, 随体重增加, 怀胚量呈显著增加的趋势。不同体重组间, 体重为1.00—3.99 g的铜锈环棱螺间的怀胚量没有显著差异, 而其他各体重组间均存在显著差异。仔螺生长特性, 6月和7月为铜锈环棱螺仔螺的快速生长期, 壳高相对增长率分别为47.95%和36.99%, 体重相对增长率分别为180.60%和128.43%。铜锈环棱螺仔螺壳宽、壳口宽与壳高呈正相关的线性关系, 壳高和体重呈正相关的幂函数关系, 壳高-体重拟合方程为W=0.0005H2.785, 壳高生长方程为H_t=19.368/(1+3.608e–1.056t), 拐点壳高为9.684 mm, 拐点月龄为1.215月, 最大月增高5.113 mm。体重生长方程为W_t =2.012e–5.051exp(–0.753t), 拐点体重为0.740 g, 拐点月龄为2.151月, 最大月增重0.557 g。综上, 稻田养殖铜锈环棱螺的产仔高峰期为6月, 2月龄达到性成熟, 6月和7月是仔螺的快速生长期。     

三角鲤的繁殖与生长特性

对三角鲤的年龄与生长、食性和繁殖进行了研究。三角鲤体长和体重相关 ,关系方程式为W =0 0 1 1 3 71L3 3 2 44。 3 龄以前生长较快 ,生长指标高 ,体长和体重的瞬时生长率大。其生长规律符合VonBertalanffy方程 :Lt=5 7 2 5 [1 -e-0 11717(t 2 9614 7) ];Wt=6762 0 4[1 -e-0 11717(t 2 9614 7) ]3 。生长拐点tr=6 41龄。其食性是以底栖动物为主的杂食性鱼类。性成熟年龄雌鱼为 3 龄 ,雄鱼为 2 龄 ,相对繁殖力为 5 5～ 88粒 g体重。一年多次产卵 ,产卵盛期为 4～ 5月 ,胚胎发育所需积温约为 2 3 0 0℃·h。     

珠江水系倒刺鲃生长的初步研究

对采集于珠江水系西江及北江流域的倒刺(Spinibarbus denticulatus denticulatus)样本进行了年龄鉴定和性腺组织学观察,并对鳞长、卵径等进行了测定。结果表明,倒刺鳞片的年轮特征为疏密切割型,新年轮出现时期主要在4~6月。体长和体重呈幂函数关系,西江和北江可分别用公式WX=2.498 4×10-2L2.999 6(r=0.956 1)和WB=1.373 3×10-2L2.815 9(r=0.925 3)表示。根据生长阶段分析,雌性倒刺的性成熟年龄为5龄,5龄以前为幼鱼生长阶段,5~10龄为成鱼生长阶段。雄性倒刺的性成熟年龄为3龄。3龄以前为幼鱼生长阶段,3龄以上为成鱼生长阶段。倒刺的繁殖季节为4~6月份。     

光倒刺鲃的年龄与生长的初步研究

研究了光倒刺鲃(Spinibarbus hollandi)的年龄与生长规律,结果表明:光倒刺鲃鳞片年轮特征主要为疏密切割型。体长与鳞长呈直线相关L=44.44R-11.69,体重与体长呈指数函数相关W=0.0258L2.9125,4龄以前生长较快,生长指标高,体长指标高,体长和体重的相对增长率大,其生长规律可用Von Bertalanffy方程表达:Lt=67.3[1-e-0.2018(t-0.1338)],Wt=5441.44[1-e-0.2018(t-0.1338)]3。体重生长曲线的拐点位于t=5.678,拐点体长Lr=45.313cm,拐点体重Wr=1660.885g。光倒刺鲃雌性一般在3~4龄性成熟,雄鱼3龄时性成熟。     

养殖美洲鲥的生长特性

通过对各周年生长阶段的养殖美洲鲥(Alosa sapidissima)体长、体重的测量与分析,研究了工厂化养殖美洲鲥的周年生长特性。养殖美洲鲥雌雄鱼的体长与体重关系均呈幂函数增长相关,其方程分别为,雌:W=0.8062×10~(-5) L~(3.1113)(n=122,R~2=0.997 5,P0.01);雄:W=1.0047×10~(-5) L~(3.0574)(n=125,R~2=0.997 5,P0.01),b均接近于3,呈等速生长;雌雄鱼生长均可分快速生长期(0~+龄)、稳定生长期(1~+龄)、生长衰老期(2~+龄)三个时期,雌鱼生长快于雄鱼。拟合出von Bertallanffy生长方程,雌:Lt=467.92(1﹣e~(-0.5748(t+0.1710))),Wt=1637.72(1﹣e~(-0.5748(t+0.1710)))~(3.1113);雄:Lt=389.21(1﹣e~(-0.7374(t+0.1975))),Wt=834.08(1﹣e~(-0.7374(t+0.7189)))~(3.0574)。雌雄鱼体重生长拐点分别位于1.517 8 a和1.224 7 a,属性成熟拐点,拐点前生长较快;拐点后,特别是性成熟后(2龄),2~+龄鱼的生长速度明显降低;同时,2龄鱼繁殖季节过后会出现大量死亡。建议商业化工厂化养殖美洲鲥以2龄前上市为宜。     

人工繁殖虾夷马粪海胆生长模型

以虾夷马粪海胆(Strongylocentrotus intermedius)家系为实验材料,对比分析了每个母系从孵化后到17月龄(性成熟)的体重、壳径、壳高的生长情况,并进行了生长性状间的相关分析及预测模型的构建。结果表明:5~15月龄,各家系虾夷马粪海胆在壳径、壳高与体重方面的差异均不显著(P0.05),17月龄时,各家系的生长指标出现差异(P0.05);虾夷马粪海胆壳径、壳高生长呈线性模型,而体重生长呈指数模型;利用虾夷马粪海胆各月龄生长性状数据,进行了虾夷马粪海胆壳径、壳高与体重相关关系分析,R2值为0.68~0.86,而虾夷马粪海胆父母本的生长性状与子代的生长性状相关性较低(0~0.25)。虾夷马粪海胆体重、壳径和壳高的生长预测模型表明,通过11月龄体重预测17月龄体重的准确率可达73.6%;本研究有助于深入了解虾夷马粪海胆的生长发育特征,并为其健康养殖模式构建提供理论依据。     

中街山列岛海域厚壳贻贝生物学特征及生长规律

根据2013年4月—2014年2月厚壳贻贝Ⅰ龄个体跟踪调查和2013年8—12月Ⅱ龄个体取样调查数据,利用Taylor公式、线性函数和Von Bertalanffy生长方程对中街山列岛海域厚壳贻贝生物学特征及生长规律进行了分析。结果表明:雌雄样本间壳长、壳高、壳宽、体重、贝壳重和软组织湿重差异不显著;壳长与壳高、壳宽之间有极显著的线性正相关关系,壳长与体重、贝壳重、软组织湿重之间有极显著幂函数关系;壳长生长方程为Lt=87.48(1-e-0.348(t+0.913)),体重生长方程为Wt=79.51(1-e-0.348(t+0.913))3;8—10月是厚壳贻贝生长旺季,8月下旬为性成熟拐点,建议厚壳贻贝春季苗的最佳收获期为10月中旬。     

三角帆蚌幼蚌贝壳形态及体重生长规律

为了掌握三角帆蚌幼蚌贝壳形态及体重的生长规律,采用模型拟合的方法研究了三角帆蚌（Hyriopsis cumingii）幼蚌一个生长周期内4个贝壳性状形态及体重性状的生长规律。结果显示,三角帆蚌幼蚌的贝壳形态与体重的增长过程均遵循Logistic生长模型。运用Levenberg-Marquardt迭代法估计出生长模型中的3个生长参数,得到在观测周期内各性状的生长极限值分别为,壳长9.216 cm、壳高4.985 cm、壳宽2.212 cm、全高8.262 cm、体重75.240 g;各性状的快速生长区间分别为壳长2.211 ~ 5.181月龄、壳高2.107 ~ 5.363月龄、壳宽2.712 ~ 5.470月龄、全高2.294 ~ 5.026月龄、体重4.247 ~ 8.065月龄,可见体重具有明显的生长延缓现象。各性状的瞬时增长率曲线均呈钟型,先增大到达生长拐点后又逐渐减小;瞬时增长加速度曲线为倒S型曲线,有最高和最低点;相对增长率在养殖初期最大,然后随着生长逐渐下降。上述结果可为三角帆蚌的养殖生态及选择育种提供参考。     

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.