不同引种地白背三七主要活性成分分析及其对生态因子的响应

以白背三七茎叶为研究对象,分别对陕西省12个引种试验地种植的白背三七总黄酮和B族维生素含量进行了测定和相关性分析,并采用中国气象科学数据共享服务平台获得不同产地的生态因子数据,通过冗余分析(RDA)其化学成分含量与生态因子间的相关性。结果显示：(1)不同采样地白背三七的总黄酮含量和B族维生素各成分含量有明显差异,其中洛南4个样地种植的白背三七茎叶中总黄酮含量显著高于其他8个样地,但B族维生素含量较其他8个样地的低;白背三七茎叶中总黄酮含量与B₂、B₆、B₁₂及B族维生素总量之间具有显著或极显著负相关关系。(2)种植地的海拔、降雨量和温度对白背三七黄酮类物质累积具有重要作用,其中总黄酮含量的主要影响因子是海拔和降雨量,且均呈正相关关系;降雨量和海拔对白背三七中B族维生素含量的影响均呈负相关关系。研究表明,地理位置和环境因子对白背三七活性物质含量具有重要影响,以洛南为代表的秦巴山区(海拔800～900 m,7～8月平均降雨量78～84 mm,平均地温26～27.5 ℃)是栽培白背三七较适宜的生态区。     

SARS冠状病毒结构蛋白在血清学诊断中潜在应用价值的比较

为了确定特异的SARS抗体检测抗原,比较了SARS冠状病毒(SARS-CoV)主要结构蛋白与SARS患者血清的反应性。从SARS死亡患者的肺组织提取的总RNA为模板,用RT-PCR技术分别扩增S、N、M和E4种结构蛋白基因,对3种S截短突变体和N、M、E的重组蛋白在大肠杆菌中进行表达。以表达的蛋白为抗原,应用Western blot跟踪检测11例SARS患者血清54份。结果显示：SARS—CoV的重组N蛋白和s蛋白有很强的抗原性,s蛋白的3个区段的抗原性强弱存在差异,S3抗原性强于S1和s2;在患病第1周、2周、3周及3周以上,N蛋白和s3蛋白抗体检出率分别为40％、65。2％、100％、100％和40％、61％、76.2％、100％;提示SARS-CoV重组N蛋白和S3蛋白在SARS的血清学诊断中有一定的应用价值。     

短波紫外线照射对‘金都’火龙果采后保鲜的影响

以‘金都’火龙果(Hylocereus polyrhizus ‘Jindu’)果实为试材,采用波长254 nm紫外杀菌灯为辐射源,给予不同剂量短波紫外线(Ultraviolet-C,UV-C)照射处理,探讨低剂量UV-C对火龙果采后保鲜的影响及作用机理。结果表明,不同剂量UV-C照射处理能有效抑制‘金都’火龙果果实腐烂和电导率上升,降低果实TSS含量,其中1.0 kJ·m–2紫外线辐照效果最好。1.0 kJ·m–2 UV-C处理能极显著提高贮藏期火龙果的SOD和CAT活性,显著提高贮藏早中期的几丁质酶活性和PPO活性,β-1,3葡聚糖酶活性在贮藏后期也显著高于对照,但降低了火龙果贮藏中期(第6天)的POD活性。此外,1.0 kJ·m–2 UV-C处理显著提高火龙果贮藏期H2O2含量(除第6天外),对果实的失水率无影响。采后火龙果应用适当剂量UV-C照射可提高抗病性,延长贮藏保鲜期。     

Karyotype Evidence for Distinguishing Between Hemerocallis esculenta and H. middendorfii

Hemerocallis dumortierii, H. esculenta and H. middendorfii were considered to belong to a biological complex, and were treated as different varieties of the same species, H. dumortierii. The present authors observed and compared the karyotypes of H. esculenta and H. middendorfii. Two plant samples for each of the species were studied. One sample of H. esculenta was from Wuán County, Hebei Province, at an altitute of 1000 m, the other from Shennongjia, Hubei Province, altitute 2100 m. The two samples of H. middendorfii were respectively from Antu County, at an altitute of 700 m, and Tonghua, altitute 500 m, in Jilin Province. The karyotypes are 2n＝2x=22=12m+8sm+2T for H. esculenta, while 2n＝2x＝22=10m+6sm+4st+2T for H. middendorfii. The karyotypical difference between the two taxa was obviously not intraspecific but interspecific. Based on the karyotype data as well as the morphological and phytogeographical data available, it is considered that H. esculenta and H. middendorfii should be recognized as different species, instead of different varieties of the same species as in literature, and that H. mid-dendorfii is more advanced than H. esculenta.     

四种观赏凤梨的离体繁殖

以粉菠萝[Aechmea fasciata (Lindl.)Baker]、八宝剑（Vriesea poelmanii Hort.)、虎斑姬凤梨[Cryptanthus zonatus(Vis.)Beer]、七彩羞凤梨[Neoregelia carolinae (Beer)L.B.Sm.]等的幼株茎段为外植体,以MS＋NAA 0.5mg L^-1 BA 5mg L^-1为诱导培养基,MS＋BA 1mg L^-1 NAA 0.1mg L^-1为增殖培养基,可获得较好增殖效果。用1／2MS＋NAA 0.5mg L^-1生根效果较好,以椰糠：砂＝1：1,或椰糠：泥炭土：蛭石＝1：1：1为基质移苗的成活率均达95％以上。     

Isolation and characterization of dengue virus serotype 2 from the large dengue outbreak in Guangdong,China in 2014

Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in China.Since July 2014,an unexpected large dengue outbreak has occurred in Guangdong province,China,resulting in more than 40000 patients including six deaths.To clarify and characterize the causative agent of this outbreak,the acute phase serum from a patient diagnosed with severe dengue was subjected to virus isolation and high-throughput sequencing(HTS).Traditional real-time RT-PCR and HTS with Ion Torrent PGM detected the presence of dengue virus serotype 2(DENV-2).A clinical DENV-2 isolate GZ05/2014 was obtained by culturing the patient serum in mosquito C6/36 cells.The complete genome of GZ05/2014 was determined and deposited in Gen Bank under the access number KP012546.Phylogenetic analysis based on the complete envelope gene showed that the newly DENV-2 isolate belonged to Cosmopolitan genotype and clustered closely with other Guangdong strains isolated in the past decade.No amino acid mutations that are obviously known to increase virulence or replication were identified throughout the genome of GZ05/2014.The high homology of Guangdong DENV-2 strains indicated the possibility of establishment of local DENV-2 circulation in Guangdong,China.These results help clarify the origin of this epidemic and predict the future status of dengue in China.     

Cold hardiness in the black rice bug, Scotinophara lurida

Abstract.  The mechanisms and strategies for winter survival of the black rice bug Scotinophara lurida are investigated along with the relationship between cold hardiness and diapause. The ability of S. lurida to survive subzero temperatures varies depending on developmental stage, temperature and exposure duration. Mean supercooling point (SCP) varies from –7.6 to –10.7 °C with developmental stage, but is not significantly different between stages examined. The SCP also varies with season, being lowest in January and increasing rapidly in February and remaining almost at the same level (–7.3 to 9.6 °C) until April The osmolality of haemolymph of field-collected S. lurida adults rises dramatically from 53.9 mOsm kg⁻¹ in August to 75.3 mOsm kg⁻¹ in December, and then declines linearly to 57.0 mOsm kg⁻¹ in May. Field-collected S. lurida adults show a peak glucose content in October, glycerol content in November and trehalose content in December. Only trehalose content decreases after the application of the juvenile hormone analogue, fenoxycarb, suggesting that trehalose is a cryoprotectant during diapause. These various physiological and biochemical traits related to cold tolerance in S. lurida may be, at least in part, under the control of juvenile hormone through the reproductive diapause programme.     

轮钟花属的恢复及其花粉和种皮证据

光学显微镜和扫描电镜观察表明,金钱豹属(广义)花粉明显分为两个类型:Campanumoea inflata和C.javanica subsp.laponica的花粉5～8沟,外壁具相对密的短刺,刺高不过1μm,而C.lancifolia,C.celebica和C.parviflora的花粉3孔沟,外壁刺稀疏,高于2μm。种子表面纹饰也同样可分为 两类,前两个种一类,其种子表面网状,网眼规则而多角形,直径大于网脊宽度,网脊上的次级纹饰为念 珠状,而后三种为一类,其种子表面网眼不规则,直径与网脊宽度近相等,网脊上的次级纹饰绳索状。可 见花粉特征与种皮性状是高度相关的。后三个种所属的分类群就是被归并了的属Cyclocodon Griffith。 综合花粉、种皮及外部形态,这个属应予恢复。其近缘属应是Platycodon,而不是Campanumoea。     

氧化棉子糖分子内交联猪血红蛋白对其结构功能的影响

用高碘酸盐氧化法制得氧化开环棉子糖,并用它分别修饰处在氧合及脱氧构象的猪血红蛋白得到两种不同的修饰衍生物。与天然蛋白质相比,两种修饰后的猪血红蛋白衍生物均具有明显的抗α２β２四聚体解聚的特性。经ＳＤＳ－ＰＡＧＥ和反相ＨＰＬＣ分析发现这两种修饰衍生物均为分子内交联产物,而且交联都发生于２个β亚基之间,两种交联产物的紫外－可见光谱没有明显差别,但在相同浓度下,脱氧构象下被修饰蛋白质的荧光发射光强度明显