HPLC法测定国产葡萄酒中白藜芦醇的含量

采用HPLC法测定国产葡萄酒中白藜芦醇的含量。色谱条件为 :Shim packCLC ODS柱 (15 0mm× 6 0mm) ,流动相 :0 2mol/LH3 PO4 CH3 CN(2 0∶80pH 3 0～ 3 5 ) ,在 30 6nm测定。测得 15种国产葡萄酒中通化干红葡萄酒的白藜芦醇含量最高为 5 6 0mg/L。该方法灵敏 ,重现性好     

乙型肝炎病毒X基因准种特点的研究

以乙型肝炎病毒（ＨＢＶ）Ｘ基因序列的异质性表现来探讨ＨＢＶ准种在　慢性感染者中的存在状态。以中国株ＨＢＶ基因序列为依据,设计特异性多聚酶链反应引物,　自９例慢性ＨＢＶ感染患者血清中扩增ＨＢＶ　Ｘ基因,克隆入ｐＧＥＭ　Ｔｅａｓｙ质粒,随机挑选克隆进行Ｄ　ＮＡ测序以确定病毒的变异程度。３７例测序结果提示来源于不同患者ＨＢＶ　Ｘ基因序列高度保守　,但每个序列均不一致。Ｘ区除了存在广泛的碱基点替换突变外,序列的缺失突变占测序克　隆总数的５１．４％（１９／３７）;氨基酸缺失及移框突变多发生于１２３位氨基酸残基之后,可导致Ｘ蛋　白多种羧基端形式。结果提示ＨＢＶ长期携带者体内有ＨＢＶ准种共存,Ｘ区内存在热点缺失突变区,该区突变结果可能影响Ｘ蛋白反式激活功能。     

不同放牧条件下锡林郭勒典型草原土壤水分分布特征及降水入渗估算

由人类活动所导致的锡林郭勒草原草场退化、土地沙化等问题日趋严重, 区域土壤水资源评价及其科学管理显得尤为重要。为确定锡林郭勒典型草原不同放牧条件对深层土壤剖面水分动态及降水入渗补给的影响, 选取1979年以来禁牧(UG79)、1999年以来禁牧(UG99)和持续放牧(CG) 3个小区6个土壤剖面, 基于不同深度土层的质量含水量、Cl ^-浓度等数据, 分析了放牧对深层土壤水分特征的影响, 且利用氯质量平衡法估算了降水入渗补给量。结果表明: 1)禁牧可以提高土壤含水量, 且禁牧时间越长, 效果越显著, 尤以表层最为明显。整个土壤剖面(0-5 m)土壤质量含水量的平均值表现为UG79 > UG99 > CG, 但各处理间差异不显著; 0-2 m UG79处理土壤剖面质量含水量分别比UG99和CG处理高26.6%和33.7%, 储水量分别高87.19 mm和82.52 mm, 且UG79处理与UG99、CG差异显著, 但UG99与CG之间差异不显著; 除局部地区受土壤颗粒组成影响含水量不同外, 各处理2-5 m土层含水量和储水量差异较小; 2)不同处理土壤含水量影响因素不同, 0-2 m土层含水量主要受地表植被状况和土壤性质的综合影响, 而2-5 m土层则主要受土壤颗粒组成的影响, 但随着禁牧年限的增加, 土壤有机质(SOM)含量对土壤水分的影响越来越大。UG79整个土壤剖面含水量与土壤颗粒含量和SOM含量呈极显著相关关系, UG99与CG处理0-2 m含水量与SOM含量呈极显著相关关系, 2-5 m土壤含水量与土壤颗粒含量呈极显著相关关系, 而与SOM含量相关性不显著; 3)氯质量平衡法估算得出年降水入渗补给率为UG79 > UG99 > CG, 35年和15年禁牧分别将降水入渗补给率提高了130.2%和44.5%; 考虑干沉降的不确定性, 研究区年降水入渗补给率为1.95-7.61 mm·a ^-1, 仅占年降水量的0.55%-2.13%。总之, 禁牧能够增加土壤含水量和储水量, 增加降水对土壤水分的补给, 但降水不是该区地下水的主要补给源。     

Association between SSR markers and fibre traits in sea island cotton (<Emphasis Type="BoldItalic">Gossypium barbadense</Emphasis>) germplasm resources

Identification of molecular markers associated with fibre traits can accelerate cotton marker-assisted selection (MAS) programmes. In this study, Gossypium barbadense germplasm accessions with diverse origins (\(n = 123\)) were used to perform association analysis of fibre traits with 120 polymorphic simple sequence repeat (SSR) markers. In total, 120 polymorphic primer pairs amplified 258 loci with a mean of 2.15 loci per primer. Population structure analysis identified three main clusters for the accessions, which indicated agreement of genetic and predefined populations. Marker–trait associations (\(n= 58\)) were detected for 10 fibre traits with 26 SSR markers located on 15 chromosomes. The \(R^{2}\) (phenotypic variation explained) ranged from 3.19 to 15.21%. Two markers (NAU5465 and NAU3013) were found to be stably associated with boll number per plant (BNP) and fibre uniformity (UI), respectively. Four markers (BNL252, NAU3424, NAU3324 and CGR5202) associated with fibre quality traits preferentially clustered on the D8 chromosome, which was thus identified as an important candidate region for study molecular mechanisms underlying fibre quality and for use in breeding cotton cultivars for improving fibre quality. This study generated molecular data with a potential for better understanding of the genetic basis of the fibre traits and provided new markers for MAS in G. barbadense breeding programmes.     

黄土丘陵区不同土地利用模式对深层土壤含水量的影响

对陕北米脂人工经济林、神木退耕还林和榆林榆阳区防风固沙林具有代表性植被类型0～20 m土壤剖面水分特征的差异进行了研究,分析黄土丘陵区不同土地利用模式对深层土壤剖面水分分布和储存特征的影响及生态环境效应.结果表明: 在0～20 m土层,不同位点具有代表性土地利用方式均影响土壤含水量的垂直分布;在整个剖面中,人工经济林土壤储水量有显著差异,为矮化枣树 ＞ 未矮化枣树,储水量相差587.9 mm;神木退耕还林和榆林榆阳区防风固沙林土壤剖面中土壤储水量无较大差异,在神木整个剖面中土壤储水量的大小为退化人工草地 ＞ 柠条林,储水量相差98.8 mm;在榆阳为荒草地 ＞ 樟子松,储水量相差7.5 mm.与未矮化枣树相比,人工经济林矮化枣树减少了对土壤水分的消耗,矮化枣树冠幅较小,降低了蒸腾作用,从而更加有利于土壤水分的可持续利用;人工柠条林和退化人工草地土壤水分含量无明显差异,这是因为退化人工草地过去为苜蓿地,根系分布深以及生物量大,对土壤深层水分利用较大所致;防风固沙林樟子松与荒草地整个剖面中的平均土壤含水量较低,土壤砂粒含量较高,土壤持水性差,土壤含水量随土壤深度的增加而增加,平均土壤含水量分别为3.4%和3.6%,且该地植物对深层土壤水分影响有限.综上,土壤剖面中土壤水分除了受土壤质地的控制,不同土地利用模式由于植物根系不同,对土壤水分也产生较大的影响.为此,选择合适的植物对于土壤深层水的保护和持续利用非常重要.     

猪细小病毒vp2基因的表达和类病毒颗粒的构建

利用PCR方法从病毒基因组中获得了vp2完整的编码区并经测序后克隆到原核表达载体pET-32(a)上.在大肠杆菌中诱导表达了VP2与Trx-His-S Tag的融合蛋白,通过免疫家兔获得了高特异性的兔抗血清.另外,将vp2克隆到pFastBacDUAL载体上,利用昆虫表达系统,即AcMNPV的Bac-to-Bac系统对vp2进行了表达,经SDS-PAGE和Western blot分析,表达产物为64kD,并且该蛋白能在昆虫细胞中形成类病毒颗粒.     

Computation of writhe in modeling of supercoiled DNA

We describe four previously unpublished methods allowing the computation of the writhe for a supercoiled DNA molecule modeled by a polymer chain consisting of straight segments. These methods are compared with each other in terms of computational efficiency and the scope of their applicability is discussed.     

用EP-9方案对两台尿液干化学分析仪进行比对及评价

目的:探讨用EP-9方案对尿干化学分析仪进行比对的可行性.方法:以不久前刚进行过定标和校准,参加江苏省临检中心室间质评获得优秀成绩、平日工作状态良好,日常工作精密度高的H-300仪器作为实验仪器,另一台仪器与其比对.采用EP-9方案的方法,连续5天,每日随机选取8份阳性新鲜尿样本,共40个标本,分别双次测试,进行统计学分析.同时对5日阳性室内质控结果功例进行符合率统计.结果:质控结果符合率为100％.仪器比对结果均符合一致性要求.结论:实验仪器与比对仪器间的结果高度一致,EP-9方案方法可适用于尿液干化学仪器的比对.     

Revision of the Eastern Asian genera Ambrostoma Motschulsky and Parambrostoma Chen (Coleoptera: Chrysomelidae: Chrysomelinae)

The leaf beetle genera Ambrostoma Motschulsky, 1860 and Parambrostoma Chen, 1934 have been revised and now include 14 species. Two new species from Nepal are described, Parambrostoma kippenbergi sp.n. and P. medvedevi sp.n. Three new synonymies are established: Ambrostoma rugosopunctatum Chen = Ambrostoma (Parambrostoma) laosensis Kimoto & Gressitt, syn.n. , Ambrostoma rugosopunctatum Chen = Ambrostoma daccordii Medvedev, syn.n., Ambrostoma fortunei (Baly) = Ambrostoma quadriimpressum chusanica Gruev, syn.n . One species was transferred from Chrysomela Linnaeus to Ambrostoma Motschulsky: A. superbum (Thunberg), comb.n . All the species now included are described and illustrated. Microcomputer tomography was applied for the first time in a study on chrysomelid beetles. A cladistic analysis based on morphological characters of adults was conducted to reconstruct the intergeneric and interspecific phylogeny of Ambrostoma and Parambrostoma. The results show that the monophyly of both genera is well supported. Ambrostoma is widespread in East Asia, whereas Parambrostoma is restricted to the southern slope of the Himalayas, where a relatively recent and modest speciation took place.