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AI-2 Key Enzyme S-Ribosylhomocysteinase from Strain Klebsiella pneumoniae CICC 10011 Producing 2,3-Butanediol

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Chemical Research in Chinese Universities 2011年第2期27卷 273-276页

作者： DAI Jian-ying zhang li-fu XIU Zhi-long School of life Science and Biotechnology Dalian University of Technology Dalian 116024 P. R. China

S-Ribosylhomocysteinase（LuxS） is the key enzyme in the synthetic pathway of a quorum sensing autoinducer AI-2. LuxS from a 2,3-butanediol produced strain Klebisella pneumoniae CICC 10011 was cloned and characterized. The luxS gene is composed of 540 bp with 172 amino acids encoded. The Km value for S-ribosylhomo- cysteine（SRH） was （27±1） umol/L, kcat was （0.112±0.004） s-1 and kcat/Km was 4.4×103 L umol-1·s-1 at 25 ℃. LuxS was activated by divalent metal ions, the highest activity was detected with Co2＋ form, followed by Mg2＋, Ba2＋, Mn2＋, Fe2＋ and Ca2＋, and activation constant for Co2＋ is （16±2） umol/L.

关键词： S-Ribosylhomocysteinase(LuxS) Kinetics Characterization Klebsiellapneumoniae

The Effects of Graded Abomasal Glucose Infusion on Milk Yield and Composition in Lactating Goats

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Agricultural Sciences in China 2010年第5期9卷 745-753页

作者： liN Xue-yan zhang Na li fu-chang WANG Zhong-hua College of Animal Science Shandong Agricultural University Tai＇an 271018 P.R. China

Four non-pregnant multiparous lactating goats were used in a 4 × 4 latin square experiment in the present study. The four treatments were abomasal infusion of 0, 50, 100, and 150 g d^-1 glucose. The results showed that graded glucose infusion increased milk yield （P 〈 0.01）. The highest milk yield was observed when 50 g d^-1 glucose was infused. An infusion of glucose at 100 or 150 g d^-1 failed to increase milk yield further and milk yield of the 100 g d ^-1 glucose infusion treatment was even significantly lower than that of the 50 g d^-1 treatment （P 〈 0.01）. Though milk fat content was gradually decreased by graded glucose infusions and milk fat yield of the 100 and 150 g d 1 treatments were lower than that of the control （P 〈 0.01）; milk fat yield of the 50 g d i treatment was not depressed and was higher than that of the control （P 〈 0.01）. Graded glucose infusion did not change the contents of milk protein and non-fatty solids. Yields of milk protein （P 〈 0.05）, lactose （P 〈 0.01）, non-fat solids （P 〈 0.01）, and lactose content （P 〈 0.01） of the 50 g d^-1 treatment were higher than those of the control but had no difference among the other three treatments. Contents of those de novo synthesized fatty acids in milk fat remained unchanged or increased and those preformed fatty acids remained unchanged or decreased by graded glucose infusion. Glucose infusion decreased the total yields of C16 ＋ C16：1 and 〉 C16 fatty acids and had no influence on the yield of C4-C14：1 fatty acids （P 〈 0.05）. Results of the present study implied that increased glucose supply had positive effects on the production of milk, milk protein, milk fat, and lactose only when glucose was a limiting factor for milk synthesis. Excessive glucose supply had no further beneficial effects and might depress milk fat synthesis.

关键词： lactating goats glucose milk yield milk composition abomasal infusion

Synthesis of highly concentrated,carrier free ^(188)Re-mercaptoacetyltriglycine

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Nuclear Science and Techniques 2002年第4期13卷 237-243页

作者： zhang Xiu-li, WANG Yong-Xian, li Jun-ling, zhang Chun-fu, WANG li-Hua,YIN Duan-Zhi(Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800) Shanghai Institute of Nuclear Research the Chinese Academy of Sciences 201800

Chelation of 188Re to compounds such as MAG3 will further reduce the radiation dose to the patient in case of balloon rupture through the rapid excretion from the body. In order to prepare highly concentrated, carrier free 188Re-MAG3, Sbenzoyl mercaptoacetyltriglycine (S-Bz-MAG3) was synthesized, labeled with carrier free 188Re. The overall yield of S-Bz-MAG3 is higher than those published in theliterature. Dependence of the labeling yield of 1ssRe-MAG3 upon concentrations of reducing agent, pH, reaction time, etc. was examined and optimum conditions were confirmed. The concentration procedure was succeeded with Sep-Pak C18 cartridge to obtain highly concentrated 1s8Re-MAG3. In the case of optimun conditions, the labeling yield of 188Re-MAG3 was more than 98%. Radiochemical purity of 188ReMAG3 was more than 92% after 24 hour storage at room temperature.

关键词：放射同位素 ^188Re 放射免疫疗法

Effect of lymphadenectomy extent on advanced gastric cancer located in the cardia and fundus

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World Journal of Gastroenterology 2008年第26期14卷 4216-4221页

作者： Chang-Ming Huang Bi-Juan lin Hui-Shan Lu Xiang-fu zhang Ping li Jian-Wei Xie Department of Oncology Affiliated-Union Hospital of Fujian Medical University Fuzh-ou350001 Fujian Province China

AIM： To analyze the prognostic impact of lymphade-nectomy extent in advanced gastric cancer located in the cardia and fundus. METHODS： Two hundred and thirty-six patients with advanced gastric cancer located in the cardia and fundus who underwent D2 curative resection were analyzed retrospectively. Relationships between the numbers of lymph nodes （LNs） dissected and survival was analyzed among different clinical stage subgroups. RESULTS： The 5-year overall survival rate of the entire cohort was 37.5%. Multivariate prognostic variables were total LNs dissected （P 〈 0.0001; or number of negative LNs examined, P 〈 0.0001）, number of positive LNs （P 〈 0.0001）, T category （P 〈 0.0001） and tumor size （P = 0.015）. The greatest survival differences were observed at cutoff values of 20 LNs resected for stage Ⅱ（p = 0.0136）, 25 for stage Ⅲ（P 〈 0.0001）, 30 for stage Ⅳ（P = 0.0002）, and 15 for all patients （P = 0.0024）. Based on the statistically assumed linearity as best fit, linear regression showed a significant survival enhancement based on increasing negative LNs for patients of stages Ⅲ （P = 0.013） and Ⅳ（P = 0.035）. CONCLUSION： To improve the long-term survival of patients with advanced gastric cancer located in the cardia and fundus, removing at least 20 LNs for stage Ⅱ,25 LNs for stage Ⅲ, and 30 LNs for stage N patients during D2 radical dissection is recommended.

关键词： Stomach neoplasms Lymph node meta-stasis Surgery Lymphadenectomy Prognosis

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo li fu Tang Jingkai zhang Yuetong Kang Hean zhang lidong li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

Prognostic impact of metastatic lymph node ratio in advanced gastric cancer from cardia and fundus

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World Journal of Gastroenterology 2008年第27期14卷 4383-4388页

作者： Chang-Ming Huang Bi-Juan lin Hui-Shan Lu Xiang-fu zhang Ping li Jian-Wei Xie Department of Oncology Affiliated Union Hospital of Fujian Medical University Fuzhou 350001 Fujian Province China

AIM: To investigate the prognostic impact of the metastatic lymph node ratio (MLR) in advanced gastric cancer from the cardia and fundus. METHODS: Two hundred and thirty-six patients with gastric cancer from the cardia and fundus who underwent D2 curative resection were analyzed ret- rospectively. The correlations between MLR and the total lymph nodes, positive nodes and the total lymph nodes were analyzed respectively. The influence of MLR on the survival time of patients was determined with univariate Kaplan-Meier survival analysis and mul- tivariate Cox proportional hazard model analysis. And the multiple linear regression was used to identify the relation between MLR and the 5-year survival rate of the patients. RESULTS: The MLR did not correlate with the total lymph nodes resected (r = -0.093, P = 0.057). The 5-year overall survival rate of the whole cohort was 37.5%. Kaplan-Meier survival analysis identified that the following eight factors influenced the survival time of the patients postoperatively: gender (χ2 = 4.26, P = 0.0389), tumor size (χ2 = 18.48, P linear correlation between MLR and the 5-year survival was statistically significant based on the multiple lin- ear regression (β = -0.63, P fundus. The decrease of MLR due to adequate number of total resected lymph nodes can improve the survival.

关键词： Lymph node metastasis Metastatic lymph node ratio Lymphadenectomy Prognosis

Study on the Anisotropy of Meniscus in the Growing Sapphire

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Chinese Journal of Aeronautics 2006年第B12期19卷 78-81页

作者： YAO Tai ZUO Hong-bo HANJie-cai MENG Song-he zhang Ming-fu li Chang-qing Grigoryan Benik Center for Composite Materials Harbin Institute of Technology Harbin 150006 China

This study is aimed at predicting the relationship between the meniscus and the quality of the sapphire crystals produced by the micro-pulling and shoulder at cooled center （SAPMIC） technique. As with different orientations, the shapes of the meniscus vary, so an investigation into the anisotropy of the meniscus shapes is very important for the final quality of the sapphire crystal. An effective model to describe meniscus shapes and their formation process has been presented. The model has been applied to a sapphire crystal of 200 mm diameter in order to check its reliability. The results show that the model proves to be useful for forecasting the final shapes of the sapphire crystal made by the SAPMIC technique.

关键词： anisotropy meniscus simulation sapphire

Induced Effects of Exogenous Phenolic Acids on Allelopathy of a Wild Rice Accession(Oryza longistaminata,S37)

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Rice science 2010年第2期17卷 135-140页

作者： Xu Gao-feng zhang fu-dou li Tian-lin Wu Di zhang Yu-hua Agricultural Environment ＆ Resource Research Institute Yunnan Academy of Agricultural Sciences Kunming 650205 China

Four exogenous phenolic acids, including salicylic acid, fumalic acid, p-coumaric acid and p-hydroxybenzonic acid, were used to investigate the regulatory effects on allelopathy of a wild rice accession of S37 （Oryza Iongistaminata）, which is a known allelopathic rice. The four exogenous phenolic acids induced the enhancement of the allelopathic potential of wild rice S37 in target weeds though the weed-suppressive activities were low, and the inducible effects were dependent on the specific phenolic acid, concentration and treatment time. After foliar application of exogenous phenolic acids, the inhibition rates for plant height, root length and fresh weight of barnyard grass （Echinochioa crus-galli） were significantly higher than those of the control. Especially at the concentration of 100 mg/L, the inhibition rates for plant height and fresh weight of barnyard grass by fumalic acid were 38.12% and 26.31% higher than those of the control, showing that fumalic acid was more effective compared with other phenolic acids in inhibiting monocotyledon weed growth. furthermore, the weedsuppressive activity of aqueous extract from the leaves of wild rice S37 treated with exogenous phenolic acids was increased, and it peaked at 48 h after the treatment with the aqueous extract, and then gradually declined.

关键词： salicylic acid fumalic acid p-coumaric acid p-hydroxybenzoic acid phenolic acid allelopathy inducible effect Oryza Iongistaminata

地震反射层夹角外推法定量确定地层超覆线位置——以陈家庄凸起东段北部缓坡带馆下段为例

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石油地球物理勘探 2008年第5期43卷 573-577,486页

作者：张福利中国石化胜利油田有限公司物探研究院山东东营257022

陈家庄凸起东段北部缓坡带主要发育了馆下段地层超覆油气藏,因此准确确定地层超覆线位置对于指导油气勘探具有重要意义。基于前人研究成果,本文依据地层超覆线正演模拟结果的分析认为,地层超覆线附近的地震反射同相轴尖灭点位置受不整... 详细信息

陈家庄凸起东段北部缓坡带主要发育了馆下段地层超覆油气藏,因此准确确定地层超覆线位置对于指导油气勘探具有重要意义。基于前人研究成果,本文依据地层超覆线正演模拟结果的分析认为,地层超覆线附近的地震反射同相轴尖灭点位置受不整合面倾角、地层倾角等因素的控制,沿着地震反射同相轴的变化趋势外推可定量确定地层超覆点的位置。该方法用于陈家庄凸起东段北部缓坡带馆下段超覆油气藏勘探,取得了满意效果。

关键词：地震反射夹角外推地层超覆陈家庄凸起地层尖灭样式