121 research outputs found

    Allophycocyanin Purification from Porphyra haitanensis and Studies on Spectrum of Eluting Fractions

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    以福建省平潭县坛紫菜(Porphyra haitanensis)为材料,采用硫酸铵分级分离和柱层析法纯化别藻蓝蛋白(APC),并对纯化的条件进行了详细的探讨。研究结果表明:采用30%~35%饱和硫酸铵沉淀、Tris-HC l(pH=8.0)作为洗脱缓冲液、DEAE-Sephadex-A-50作为层析介质,所获得的APC的纯度和回收率分别为3.50和70.2%;SDS-PAGE表明APC有α和β两个亚基,分子量分别为18.9 kD和17.7 kD。因此该方法对于从坛紫菜中快速纯化APC是适合的。采用光谱分析研究柱洗脱组分,结果表明:坛紫菜中含有分子结构为(αβ)6γ的“双峰型”R-PE,含有结构为(αβ)3的R-PC,含有结构为(αβ)3的APC-Ⅱ。Allophycocyanin from Porphyra haitanensis collected in Pingtan County of Fujian Province was purified using ammonium sulfate precipitation and column chromatography.Meanwhile,factors of purification were studied in detail.The results showed that using 30%-35% of the saturation ammonium sulfate precipitation,Tris-HCl(pH=8.0)as eluting buffering and DEAE-Sephadex-A-50 as(chromatogra-)(phic) adsorbent;the purity and rate of recovery of allophycocyanin obtained were 3.50 and 70.2%,(respectively).SDS-PAGE demonstrated the presence of two subunits,α and β,with Mr(18.9 kD) and(17.7 kD),respectively.Therefore the method was suitable for quick purification of allophycocyanin from P.haitanensis.At the same time,the fractions collected from column were researched by analysis of spectrum.The findings indicated that P.haitanensis contained the R-phycoerythrin with two absorption peaks which had the polypeptide composition(αβ)_6γ,the R-phycocyanin which had the polypeptide composition(αβ)_3 and allophycocyanin-II which had the polypeptide composition(αβ)_3.国家海洋863项目(2002A603023)资

    金定鸭3个品系间的杂交效果分析

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    金定鸭3个品系间的杂交效果分析赖垣忠,陈奕欣,陈小麟,吕良炬,潘丽娉(福建厦门大学生物学系361005)纵观现代国际家禽业,就家食品种而言,几乎都采用商品配套品系。虽然,品系的育成方法不尽一致,但都是在现代遗传育种理论指导下,获得加性和非加性遗传效应...“八五”农业部畜牧兽医司资

    Effect of gastrectomy on G-cell density and functional activity in dogs

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    Billroth gastrectomy has some advantages of inhibiting acid secretion, low ulcer recurrence and low mortality. However, postoperative complications, such as dumping syndrome and reflux gastritis, often occurred as a result of pylorectomy [1] . To minimize these complications, pylorus-preserving gastrecto my (PPG) had been performed for gastric ulcer with satisfied clinical results. P ositive correlation was not found between ulcer recurrence and serum gastrin level [2] . In this study, we performed distal partial gastrectomy with Billr oth II anastomosis (DPG-BII), pylorus-preserving gastrectomy (PPG) and highly seclective vagotomy (HSV) on dogs and investigated the relationship between dif ferent antrum disposal and gastric acid secrection, serum gastrin level and G-cell density and functional activity

    Effects of tributyltin on alkaline phosphatase,aaciphosphatase andadenosine triphosphatase gill activity of digestive gland in clam Meretrix meretrix

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    在实验生态条件下,观察浓度分别为0.1、1.0和10ng/L的三丁基锡(TBT)暴露2、8、20d以及恢复7d和20d后对文蛤鳃酸性磷酸酶(aaciphosphatase,ACP)、碱性磷酸酶(alkalinephosphatase,AKP)以及Na+,K+-ATPase活性的影响。结果显示在暴露早期TBT不影响ACP、AKP活性,暴露时间延长则主要表现出诱导作用。TBT具有抑制Na+、K+-ATPase活性作用,可观察效应浓度为0.1ng/L。Na+、K+-ATPase可作为一种潜在的有机锡污染监测的生物标志物。The effects on alkaline phosphatase, aaciphosphatase and Na~+K~+-ATPase activities in the gill of Meretrix meretrix, which was exposed to tributyltin (TBT) at the environmental levels (0.1ng/L, 1.0ng/L, 10ng/L as Sn) for 2, 8, 20 days and recovered for 7, 20 days, were evaluated. The results showed that the activities of alkaline phosphatase, aaciphosphatase were no effect at earlier exposure period, and were principally inducted with prolonged exposure time. The activities of Na~+,K~+-ATPase in Meretrix meretrix were inhibited after exposure to TBT. The lowest observable effect concentration for Na~+K~+-ATP were 0.1 ng /L. Na~+,K~+-ATPase could be a potential biomarkers to monitor the organotins pollution.厦门大学细胞生物学与肿瘤细胞工程教育部重点实验室开放基金资助(2004109

    Effects of tributyltin on antioxidant enzymes activity and lipid peroxidation in the gill of hard clam Meretrix meretrix

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    在实验室条件下,观察质量浓度分别为高、中、低(0·1,1,10ng·L-1(以Sn计))3组的三丁基锡(TBT)暴露2、8、20d以及恢复7d和20d后对文蛤鳃的谷胱甘肽硫转移酶(GST)、过氧化氢酶(CAT)活性以及丙二醛(MDA)含量、还原型谷胱甘肽(GSH)含量的影响.结果显示,除了高浓度TBT(10ng·L-1)暴露在早期(2d)对GSH含量、GST和CAT活性产生抑制之外,TBT暴露对GSH含量、GST和CAT活性的作用主要为诱导效应.在暴露8d后,MDA的含量表现出显著的诱导.恢复7d后除了高浓度组对MDA还有影响外,其它各指标均恢复到与对照组相当的水平.结果表明,环境水平的TBT暴露对文蛤产生明显的氧化胁迫,抗氧化防御系统可以作为海洋环境有机锡污染监测的潜在的生物标志物.The effects on catalase (CAT), glutathione -S-transferase(GST) activities and content of malondialdehyde (MDA), reduced glutathione (GSH) in the gill of Meretrix meretrix were evaluated, after it had exposed to tributyltin (TBT) at environmental levels (0.1, 1, 10 ng·L -1 as Sn) for 2, 8, 20 days and recovered for 7, 20 days, in experimental condition. The results showed that the activities of GST and CAT and GSH content in Meretrix meretrix exposed to TBT were principally induced, except that were mainly inhibited in the clams exposed to 10 ng·L -1 for 2 days. MDA content were significantly induced after exposure for 8d. After the clams had been transferred to clean recovery tanks for 7 days, the indexes were recovered to the level corresponding to the control group, except MDA content in the clams exposed to 10 ng·L -1 was sequentially induced. These results in the present work showed that oxidative stress in Meretrix meretrix would be produced by exposure to TBT at realistic levels in the environment. The antioxidant defense systems could act as biomarkers to monitor marine contamination of organotins.厦门大学细胞生物学与肿瘤细胞工程教育部重点实验室开放基金(No.2004109)~

    Benefit of radiotherapy for 90 patients with resected intrahepatic cholangiocarcinoma and concurrent lymph node metastases

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    To evaluate the role of radiotherapy for patients with resected intrahepatic cholangiocarcinoma with concurrent macroscopic abdominal lymph node metastases. We identified 90 patients with resected intrahepatic cholangiocarcinoma and concurrent regional lymph node metastases treated between 1999 and 2008, thereinto 24 patients received local limited external beam radiotherapy (classified as the radiotherapy group) with a median total dose of 50 Gy (range 34-60 Gy) in fractions of 2 Gy five times a week. The remaining 66 patients did not receive external beam radiotherapy (classified as the non-radiotherapy group). We studied survival and tumor response to radiotherapy, demonstrated by symptoms and results of imaging, by Kaplan-Meier method and Cox analysis. After radiotherapy, lymph nodes showed partial response in nine patients (37.5%) and complete response in nine patients (37.5%). Median survival was 19.1 months in the radiotherapy group and 9.5 months in the non-radiotherapy group (P = 0.011). Multivariate analysis showed that increasing age, multiple intrahepatic primary tumors, higher level of CA19-9, and non-radiotherapy group were related to a poorer prognosis. The most common cause of death was intrahepatic recurrence, and death resulting from lymph node-related complications was similar between the two groups. External beam radiotherapy seems to improve the prognosis of patients with resected intrahepatic cholangiocarcinoma and concurrent macroscopic lymph node metastases

    THETA-STATISTICS AND P, T VIOLATION IN GROUND-STATE

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    By means of the concepts in differential geometry and braid group, the general theory of theta statistics is presented. We discuss the relation between the single-valued cross-section and multi-valued wave function, the derivation of statistical potential from Kohno connection, and the violation of reflection symmetry with respect to space (P) or time (T) in the ground state

    PIRSF: family classification system at the Protein Information Resource

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    The Protein Information Resource (PIR) is an integrated public resource of protein informatics. To facilitate the sensible propagation and standardization of protein annotation and the systematic detection of annotation errors, PIR has extended its superfamily concept and developed the SuperFamily (PIRSF) classification system. Based on the evolutionary relationships of whole proteins, this classification system allows annotation of both specific biological and generic biochemical functions. The system adopts a network structure for protein classification from superfamily to subfamily levels. Protein family members are homologous (sharing common ancestry) and homeomorphic (sharing full-length sequence similarity with common domain architecture). The PIRSF database consists of two data sets, preliminary clusters and curated families. The curated families include family name, protein membership, parent-child relationship, domain architecture, and optional description and bibliography. PIRSF is accessible from the website at http://pir.georgetown.edu/pirsf/ for report retrieval and sequence classification. The report presents family annotation, membership statistics, cross-references to other databases, graphical display of domain architecture, and links to multiple sequence alignments and phylogenetic trees for curated families. PIRSF can be utilized to analyze phylogenetic profiles, to reveal functional convergence and divergence, and to identify interesting relationships between homeomorphic families, domains and structural classes

    The universal protein resource (UniProt)

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    The ability to store and interconnect all available information on proteins is crucial to modern biological research. Accordingly, the Universal Protein Resource (UniProt) plays an increasingly important role by providing a stable, comprehensive, freely accessible central resource on protein sequences and functional annotation. UniProt is produced by the UniProt Consortium, formed in 2002 by the European Bioinformatics Institute (EBI), the Protein Information Resource (PIR) and the Swiss Institute of Bioinformatics (SIB). The core activities include manual curation of protein sequences assisted by computational analysis, sequence archiving, development of a user-friendly UniProt web site and the provision of additional value-added information through cross-references to other databases. UniProt is comprised of three major components, each optimized for different uses: the UniProt Archive, the UniProt Knowledgebase and the UniProt Reference Clusters. An additional component consisting of metagenomic and environmental sequences has recently been added to UniProt to ensure availability of such sequences in a timely fashion
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