似士维螨对西洋参根的取食量及其繁殖潜势

【目的】作为西洋参Panax quinquefolium L.的新害虫,似士维螨Schwiebea similis Manson蛀食参根,造成较大的经济损失。本研究旨在测定它对参根的取食量,进而为估算其经济阈值提供参数。【方法】本实验将似士维螨活雌螨接种于含湿沙和西洋参根粉的培养皿中塑料环内,在7级雌螨接种量N_0(每环1,2,3,4,5,6和7♀)和5个温阶T(15.6,18.5,21.2,24.5和27.2℃)条件下培养其实验种群,记载并分析了5类变量:安居期D、峰螨数N_p、雌均殖数PCR、成虫当量AE和均食量FA。【结果】变量D随T升高而快速下降,也因N_0增加而缓慢下降;N_p随N_0增加而显著上升,其回归式为N_p=21.8+17.2N_0;PCR随N_0增加而显著下降,PCR=63.4-28.1N_0+6.2N_0~2-0.4N_0~3,其曲线变化趋势与N_p相反;同时发现了螨虫拥挤效应;AE随N_0增加而显著上升,AE=16.2+12.7N_0;FA=0.25±0.13 mg/头。【结论】这5类变量较为全面地反映了似士维螨实验种群的食量范围和繁殖潜势。上述估算值将为探索其经济阈值提供依据;所用实验方法将为同类研究提供参考。     

土壤中甲螨孳生与铬污染相关性研究

目的 :探讨土壤中甲螨孳生的种群数量与土壤铬污染之间的相互关系。方法 :于某大型化工厂周围土壤 10 m、1km、10 km及远郊农田土壤设立采样点 ,各采集 5 0份样本 ,每份样本采集 (10× 10× 10 )cm3的土壤 ,置 Tullgren电热分螨器中分离甲螨 ,计算甲螨在不同环境中的密度、丰度、优势属 ;同时用原子吸收光谱法分别测定化工厂周围土壤及远郊农田土壤样本中的铬含量。结果 :化工厂周围土壤总体甲螨的密度、丰度和优势度分别为 1975 7(131.71± 2 8.34)个 / m2、131.7个 /样本、嗜草甲螨、门罗点肋甲螨 ,远郊农田土壤甲螨的密度、丰度和优势度分别为 984 5 (6 5 .6 3± 18.36 )个 / m2、6 5 .6 3个 /样本、滑菌甲螨、嗜草甲螨、被盖头甲螨、棒菌甲螨、新小奥甲螨、普通尖棱甲螨 ,两者相比差异有显著性 (P<0 .0 1)。化工厂周围土壤及远郊农田土壤总体铬浓度分别为 (0 .2 5± 0 .0 7) mg/ kg、(0 .0 8± 0 .0 2 ) m g/ kg,两者相比差异有显著性 (P<0 .0 1)。化工厂周围土壤 10 m、1km、10 km、处甲螨的密度分别为 16 4 89(32 9.78± 31.2 2 )个 / m2、2 2 5 7(45 .14± 9.4 5 )个 / m2 、10 11(2 0 .0± 3.33)个 / m2 ,化工厂周围土壤样本的甲螨密度较高 ,与远效农田土壤相比 ,差异有显著性 (P<0 .0 1)。结论     

尿螨病的病原学研究

探讨引起尿螨病的病原螨种类,以离心沉淀法浓缩尿液或用铜丝筛（100目／寸）过滤,分离尿液中的螨,直接镜检鉴定螨种,从69例尿螨阳性者的尿液中共分离出17种病原螨,即：粗脚粉螨Acarus siro,腐食酪螨Tyrophagus putrescentiae,长食酪螨T.longior,椭圆食粉螨Aleuroglyphus ovatus,伯氏嗜木螨Caloglyphus berlesei,食菌嗜木螨C.mycophagus,纳氏皱皮螨Suidasianesbitti,河野脂螨Lardoglyphus konoi,家食甜螨Glycyphagus domesticus,甜果螨Carpoglyphuslactis,害嗜鳞螨Lepidoglyphus destructor,粉尘螨Dermatophagoides farinae,屋尘螨D.pteronyssinus,梅氏嗜霉螨Euroglyphus maynei,赫氏蒲螨Pyemotes hughesi,谷跗线螨Tarsonemus granarus,人跗线螨T.hominis,在同一受检者尿液中检出成螨者19例,检出幼螨者18例,同时发现成螨和幼螨者11例,成螨和卵同时检出者3例,成螨,幼螨和卵同时检出者11例,幼螨和卵同时检出者6例,休眠休和卵同时检出者1例;分别占尿螨阳性总数的27．54％,26．09％,15.94%,4.35%,15.94%,8.70%,1.44%.69例悄螨病患者每200mL尿液中检出螨数0．5个以下者32人,0．6－1个者25人,1．1＝－1．5个者10人,1．5个以上者2人,引起尿螨病的病原螨种类较多,其中粉螨是主要的病原螨。     

蔬菜类保健食品"赛金"等对大鼠肠道菌群影响的实验研究

本研究采用人工半合成饲料和代谢实验技术 ,设置对照组 ,观察了我国蔬菜类保健食品“赛金”和典型的茄果类蔬菜 -茄子冷冻干燥粉对生长中大鼠肠道菌群的影响。1　材料与方法1 .1　实验材料　“赛金”为茄子、西红柿等 1 0种新鲜蔬菜冷冻干燥粉的混合物 ,茄子冷冻干燥粉为新鲜茄子冷冻干燥制备而得。均为哈尔滨制药三厂提供。1 .2　动物与分组　选用雄性 Wistar大鼠 2 7只(为二级实验动物 ,购自中国医学科学院实验动物中心 )。平均体重 (60 .1± 1 .5) g,随机分为 3组。于空调动物实验室内、在全塑代谢笼内单独饲养 ,环境参数 :温度 (2 3± …     

反义核酸真核表达载体的构建及其对重组HeLa细胞H654中IVS-2-654C→T突变β-珠蛋白基因剪接缺陷的抑制作用

在原工作的基础上 ,将非细胞系统中证明有效的反义片段通过高效真核表达载体 pCDNA3导入能稳定表达IVS -2 -6 5 4C→T突变 β 珠蛋白基因的重组HeLa细胞 (H6 5 4)中 .结果显示 ,转染后第 3天 ,H6 5 4细胞内正常剪接的β -珠蛋白mRNA水平 ( β/( β + β *) )明显上升 ,从 0 0 7上升到 0 2 2 ,并维持到第 1 5天 ,最高达到0 43.实验表明构建的反义片段真核表达载体在细胞中能稳定转录反义RNA并有效抑制IVS -2 -6 5 4C→T突变β 珠蛋白基因的异常剪接 ,为开展反义核酸治疗剪接缺陷型遗传性疾病提供了更直接的科学依据     

链霉菌发酵麦草产木聚糖酶的试验研究

通过正交设计试验 ,找出利用链霉菌和麦草基质发酵生产木聚糖酶的试验条件。培养基 (g/L) :麦草粉 ,4 5 ;(NH4 ) 2 SO4 ,7.5 ;酵母膏 ,8;K2 HPO4 ·3H2 O ,1;MgSO4 ·7H2 O ,0 .5 ;NaCl,0 .3。接种量为 5 .0× 10 8个孢子 / 5 0mL培养基 ,振荡培养 (12 0r/min) 5d     

江西真长须螨属记述(蜱螨亚纲:长须螨科)(英)

本文描述了采自江西的5种真长须螨并列出检索表,其中包括3新种:江西真长须螨Eustigmaeus jiangxiensis Hu, Chen and Huang, sp. nov. ;牯岭真长须螨E. gulingensis Hu and Chen, sp. nov. ;龙氏真长须螨E. longi Hu and Chen, sp. nov. 和1中国新纪录种,塞氏真长须螨E. segnis(Koch)。     

Progress in the complete mitochondrial genomes of the Acari

蜱螨亚纲包括蜱类和螨类,是节肢动物中物种多样性最高的类群之一.本文综述了当前已测序的28种蜱螨线粒体基因组的研究成果.概括起来,蜱螨线粒体基因组具有以下特点:(1)大小变异显著,其中柑橘全爪螨Panonychus citri线粒体基因组在目前已测节肢动物中最小(13077 bp);(2)一般碱基组成偏向A和T,但6种蜱螨具有相反的GC-偏斜(正值);(3)基因组的碱基组成及A+T富集区的位置、长度和拷贝数等变异显著,其中4种叶螨的A+T含量最高,其A+T富集区在目前已测节肢动物中最短(44 -57 bp);(4)基因高度重排,特别是真螨总目的种类,但重排与高分类阶元无相关性;(5)真螨总目部分螨类的tRNA基因极度缩短,不能形成经典的三叶草二级结构.作者建议要进一步测定更多蜱螨的线粒体基因组,验证蜱螨非典型tRNA基因的生物学功能性,分析蜱螨线粒体基因组的分子进化机制,开展蜱螨线粒体转录组研究等.     

辽宁革螨的生态地理分布

辽宁省已知的革螨46种,分属于5科19属.本文依据四个不同地理景观区内革螨的优势种、常见种和罕见种,对其生态地理分布作了讨论.(1)辽西低山丘陵及沿海平原区:本区共有革螨20种,其中仓鼠真厉螨、格氏血厉螨为优势种;塔山巨刺螨、长毛鞘厉螨为罕见种.(2)辽东山地及半岛丘陵区:本区共有革螨22种.半岛丘陵革螨优势种为仓鼠真厉螨、格氏血厉螨;辽东山地革螨优势种为耶氏厉螨与东方真厉螨.本区罕见种为赛氏血革螨、达呼尔血革螨、大连肪刺螨、三角血厉螨等.(3)辽河平原区:本区共有革螨20种.优势种为耶氏厉螨与厩真厉螨;乌苏里土厉螨为罕见种.(4)努鲁儿虎山脉北麓黄土丘陵台地及西辽河沙地区:本区共有革螨26种.优势种为东北血革螨、仓鼠真厉螨及格氏血厉螨.巨腹赫刺螨、鼬赫刺螨、拟小赫刺螨、半漠血厉螨、乌苏地厉螨、北野血革螨、楠本血革螨等为罕见种.     

影响灰褐链霉菌S1001产碱性几丁质酶的因素

河南农业大学筛选的灰褐链霉菌Ｓ1 0 0 1所产碱性几丁质酶 ,经大田实验对Ｂｔ增效明显 ,但菌株产酶量低。本实验旨在探讨影响灰褐链霉菌Ｓ1 0 0 1产碱性几丁质酶量的因素。通过摇瓶发酵 ,用测菌丝干重法 ,得出了产碱性几丁质酶的灰褐链霉菌Ｓ1 0 0 1的营养生长曲线 ,确定了其对数生长期为培养开始后 2 4～ 34ｈ ;对其营养生长条件进行了优化 ,最佳营养生长条件为 :①培养基 (ｇ/Ｌ) :淀粉 2 0 ,ＫＮＯ31 .0 ,Ｋ2 ＨＰＯ41 .0 ,ＮａＣ1 0 .5 ,ＦｅＳＯ4·7Ｈ2 Ｏ 0 .1 ,ＭｇＳＯ4· 7Ｈ2 Ｏ 0 .5 ,,Ｎａ2 ＣＯ36 .0 (单独灭菌 ) ;②培养温度 …     

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.