Sequence analysis and quantitative detection of Norwalk-like viruses in cultured oysters of China     

Jun Wang  Qingjuan Tang  Zhiqin Yue  Zhaojie Li  Jin Zhang  Changhu Xue 《中国海洋大学学报(英文版)》2008,7(2):223-227

We isolated 4 Norwalk-like viruses (NLVs) contaminated oysters from 33 Chinese oysters collected from local commer-cial sources of Shandong Province. After amplification of the RNA-dependent RNA polymerase (RdRp) region of NLVs genomes with RT-PCR, the open reading frame 1 (ORF1) of the RdRp was sequenced and subjected to multiple-sequence alignment. The re-suits showed that NLVs in the four isolates belong to genogroup Ⅱ. The sequence comparison showed that the similarity between four Chinese oyster isolates were higher than 99.0%, which indicated that NLVs prevalent in close areas have high homogeneity in genome sequences. In addition, the most conserved sequences between diverse NLVs were used to design primers and TaqMan probes, then the real-time quantitative PCR assay was performed. According to the standard curve of GII NLVs, the original amounts (copies) of NLVs in positive patient's fecal isolate, positive Japanese oyster isolate, and the Chinese oyster isolate were 8.9×108, 1.25×108 and 4.7×101 respectively. The detecting limit of NLVs was 1×101 copies. This study will be helpful for routine diagnosis of NLVs pathogens in foods and thus for avoiding food poisoning in the future.  相似文献   

Identification of a Putative Tetrasporophyte-Specific Gene in Gracilaria lemaneiformis(Gracilariales, Rhodophyte)     

REN Xueying  ZHANG Xuecheng 《中国海洋大学学报(英文版)》2008,7(3)

A putative tetrasporophyte-specific gene, designated as SSH466 (GenBank accession No. DQ019223), was one of the genes identified in this work using suppression subtractive hybridization (SSH) method in Gracilaria lemaneiformis. The full length of the gene was obtained using SMART RACE strategy. Sequence analysis revealed that the gene had 1 019 nucleotides, including an open reading frame of 498 nucleotides encoding 166 amino acid residues, 158 nucleotides of 5' untranslated region and 363 nucleo- tides of 3' non-coding region. Protein motif and secondary structure prediction showed that there existed a transmembrane domain with a unique β-sheet. Thus, SSH466 protein might be a cross-membrane protein. Sequence homology search in the public GenBank databases did not reveal any significant match with SSH466. Virtual Northern blot analysis confirmed that it was a tetrasporo- phyte-specific gene.  相似文献   

Hematological changes in white spot syndrome virus-infected shrimp, Fenneropenaeus chinensis (Osbeck)     

Shouming Feng  Wenbin Zhan  Jing Xing  Jun Li  Kai Yang  Jing Wang 《中国海洋大学学报(英文版)》2008,7(3):287-293

The pathological changes of hemocytes in the haemolymph and hepatopancreas were examined in experimentally and naturally WSSV (white spot syndrome virus) infected Fenneropenaeus chinensis. The results showed that the pathological manifestations of hemocytes were similar among moribund shrimps infected via injection, feeding and by nature. Firstly, the total hemocyte counts (THCs) in WSSV-infected shrimp were significantly lower than those in healthy shrimp. Secondly, necrotic, broken and disintegrated cells were often observed, and a typical hematolysis was present in the haemolymph smear of WSSV-infected shrimp. Thirdly, necrosis and typical apoptosis of hemocytes were detected with TEM in the peripheral haemolymph of WSSV-infected shrimp. Hyalinocytes and semi-granulocytes with masses of WSSVs in their nuclei often appeared, whereas no granular hemocytes with WSSV were found in the hepatopancreas of moribund infected shrimps. All our results supported that hemocytes were the main target cells of WSSV, and hyalinocytes and semigranular hemocytes seemed to be more favorable for WSSV infection in F. chinensis.  相似文献   

Function of spa development in countryside for domestic tourism in China     

Yan-ping Wang  J. Yamamura 《中国地理科学(英文版)》2000,10(2):168-176

The common problems on tourism of developing countries have often been researched by west researchers until now, which can be concluded into special words: “two sectors”, “enclave construction”, “government’s interference”, “developing scale”, and “the industrial role of tourism” etc. In fact all the researches were done from the areas with the patronage of foreign visitors, how is the situation of domestic tourism was ignored in some points. In this paper, another developing model compared with the one with foreign visitors was presented to the readers on the case studies of countryside spas in China. Through this research, one aspect of Chinese real leisure life can be understood to some extent, and the implying that for bigger developing countries the domestic tourism can match the effect of international tourism should not be ignored at least to China. As the developing of economy, domestic tourism will finally unite with international one together, and the common problems will disappear step by step, therefore domestic tourism and international tourism of developing countries should be researched equally since now. Biography: WANG Yan-ping (1962–), male, a native of Heilongjiang Province, is a doctorate student of Chiba University of Japan. His research insterest is environmental impact assessment.  相似文献   

德国迁都柏林过程中的地球信息技术─-祝贺陈述彭院士2000年2月14日八十华诞生日快乐     

李建新 《地球信息科学学报》2000,2(1):53-59

联邦德国议会1991年决定, 议会与政府核心部门在2000年前从波恩迁回柏林 ,波恩保留联邦行政管理中心的功能。为了按时准确地规划和完成落实迁都建设工程,在柏林建设国家行政办公设施和国家工作人员生活居住设施,解决波恩地区因国家机关迁离而遭受的损失,参加建设的许多部门应用了地球信息技术。文中介绍了“柏林房地产信息系统”,“联邦议会与政府核心区建设信息系统”,“物业管理信息系统”,“波恩地区经济地理信息系统”以及地球信息技术在交通和环境管理中的应用。  相似文献   

A Review of Mineral Resources and GIS Applications in Mineral Resource Assessment in Northeast China   总被引：1，自引：0，他引：1  

Zhou Yunxuan 《东北亚地学研究》2000,(2)

IntroductionThe Northeast China region locates in the centre of Northeast Asia economic zone, and borders onRepublic of Mongolia in the north, Russian Far Eastin the east, and Democratic People, s Republic ofKorea in the south. It includes three provinces…  相似文献   

张北6.2级地震的连续形变前兆异常时空特征     

张雁滨  蒋骏  陈绍绪  王宝坤 《大地测量与地球动力学》2000,20(3):69-74

采用首都圈连续形变观测网内倾斜及应变的观测资料,对张北地震的前兆异常及其特征进行了分析研究,得到如下结果:震前1年半到两年(即1996年)在这一地区存在较大区域的连续形变异常;在这种中长异常背景的基础上,倾斜、应变观测结果再次出现新一轮异常,并且新的异常在观测地点和时间上一致,异常点相对于中长期时的空间范围缩小,向震中区集中(约200 km范围内).新一轮异常从其中最早的异常开始到地震发生在1年以内,并且随发震时间的逼近,不同观测项目和不同观测方向的各种参量的异常表现更为一致和显著,其中以离震中最近的张家口的异常变化最为突出.  相似文献   

城市地理研究中的单分形、多分形和自仿射分形   总被引：1，自引：0，他引：1  

陈彦光 《地理科学进展》2019,38(1):38-49

分形几何学在城市地理研究中具有广泛的应用,然而很多基本概念却让初学者感到迷惑。如何区分单分形、自仿射分形与多分形,是一个基本而重要的问题。简单分形容易理解,而真实的地理现象很少是单分形的。城市生长过程具有自仿射特征,而城市空间格局却具有多分形性质。作者发现,各种分形的共性在于三个方面：标度律、分数维和熵守恒。论文基于标度、分维和熵守恒公式,借助隐喻城市生长的规则分形来区分单分形、多分形和自仿射分形,讨论分形系统演化的机理、分形与空间自相关和空间异质性的联系,同时澄清一些在地理分形研究中的常见错误概念。最后以城市位序-规模分布为例,说明并对比单分形和多分形在城市地理研究中的建模与应用思路。  相似文献   

大气污染物排放量与颗粒物环境空气质量的空间非协同耦合研究——以武汉市为例     

张金亭  赵玉丹  田扬戈  何青青  庄艳华  彭韵羲  洪松 《地理科学进展》2019,38(4):612-624

针对区域大气污染物排放量与空气质量在时空分布上存在不完全协同、匹配的现象,论文选择SO₂、NO_X、PM_2.5、CO和VOCs作为大气污染物指标,选择气溶胶光学厚度(Aerosol Optical Depth, AOD)表征颗粒物环境空气质量,以武汉市为例,综合应用耦合模型和空间错位指数模型研究2类指标之间的空间非协同耦合规律。主要结论如下：① 武汉市大气污染物排放量与颗粒物空气质量具有不同空间分布特征,大气污染物排放量呈现由城市中心城区向远城区递减的趋势,其中SO₂、PM_2.5和VOCs的排放具有明显的中心聚集现象,而NO_X和CO聚集现象不显著,且与道路分布明显相关;AOD分布具有明显的空间差异性,总体上呈由西北向东南依次递减的趋势。② 武汉市大气污染物排放与颗粒物空气质量的空间非协同耦合规律：越靠近城市中心城区,空间协同耦合现象越显著,空间错位现象越弱;越远离主城区,空间非协同耦合现象越显著,空间错位现象越显著;SO₂排放量与AOD在武汉市远城区的空间错位指数均大于0.7,且耦合度指数小于0.3,呈现较强的非协同耦合特征,NO_X、VOCs、PM_2.5的排放量与AOD在武汉中心城区的空间错位指数均小于0.5,且耦合度指数大于0.5,协同耦合现象较为显著。③ 基于时空非协同耦合分析城市大气环境污染治理建议：针对污染物与AOD空间错位不显著的城市中心城区,以本地减排治理为主;针对污染物与AOD空间错位显著的远城区,应在污染溯源分析的基础上进行区域协调综合治理。  相似文献   

社区生活圈公共服务设施配置的空间分异分析——以大连市沙河口区为例   总被引：2，自引：1，他引：1  

韩增林  李源  刘天宝  董梦如 《地理科学进展》2019,38(11):1701-1711

城市公共服务设施的配置水平直接影响到居民的生活品质。论文基于高德地图获取的地图数据,使用城市网络分析工具(Urban Network Analysis Toolbox, UNA)对大连市沙河口区内的6类公共服务设施分布进行空间分异分析,并对区内90个社区的居民出行可达设施的数量及类别进行测度,最后对各个社区进行总体评价。结果表明：① 大连市沙河口区公共服务设施空间分布不均,北多南少,呈现出“一主多次”的“廾”字形的结构,主要分布在西安路商业区周边和各个街道的次级商业区;② 居民可达设施数量空间差异大,北多南少,各街道均有1或2个区域可达设施数量较多;③ 居民可达设施类型数量存在一定差异,70%以上的住宅楼中的居民可以获得全部6类公共服务设施;④ 各社区居民可达设施总体处于差异较小的均衡状态,但仍有个别社区存在内部差异较大的现象。设施的分布、地物的阻隔和社区的封闭程度对居民获取各类公共服务设施影响较大,建议构建“设施完善、便捷可达”的15 min社区生活圈。  相似文献