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西瓜ClPP2C3克隆及表达分析
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作者 朱毅 柳唐镜 +3 位作者 宫国义 张洁 王晋芳 张海英 《生物技术通报》 CAS CSCD 北大核心 2024年第1期243-249,共7页
【目的】蛋白磷酸酶2C(protein phosphatase 2C,PP2C)是动植物中均存在的一类蛋白磷酸酶,拟探究其在西瓜果实成熟过程中发挥的重要作用。【方法】通过逆转录PCR(reverse transcription-polymerase chain reaction,RT-PCR)从栽培类型西瓜... 【目的】蛋白磷酸酶2C(protein phosphatase 2C,PP2C)是动植物中均存在的一类蛋白磷酸酶,拟探究其在西瓜果实成熟过程中发挥的重要作用。【方法】通过逆转录PCR(reverse transcription-polymerase chain reaction,RT-PCR)从栽培类型西瓜‘97103’中克隆ClPP2C3,并对其进行生物信息学、表达模式和亚细胞定位分析。【结果】西瓜ClPP2C3的cDNA序列长度为1317 bp,编码438个氨基酸,其分子量大小为47.81 kD,蛋白质等电点为5.12。ClPP2C3包含1个PP2C保守结构域,与负调控果实成熟的番茄SlPP2C3、草莓FaABI1具有较高的同源性。西瓜ClPP2C3在细胞核表达。ClPP2C3在含糖量高的栽培品种中表达量显著高于含糖量低的野生品种。栽培品种ClPP2C3的2kb片段长度启动子活性显著高于野生品种,而1kb片段长度启动子活性之间无显著差异。【结论】由1-2kb区间SNP导致的启动子活性差异对不同含糖量品种ClPP2C3表达量存在影响。 展开更多
关键词 西瓜 clpp2C3 基因克隆 亚细胞定位 启动子活性差异分析
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Profile of Amoebic vs. Pyogenic Liver Abscess and Comparison of Demographical, Clinical, Radiological, and Laboratory Profiles of These Patients from Three Secondary Care Centers in Senegal
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作者 Agbogbenkou Tevi Dela-Dem Lawson Daouda Thioub +2 位作者 Ndiaga Mbengue Ndeye Amy Sarr Sylvie Audrey Diop 《Advances in Infectious Diseases》 CAS 2024年第3期595-605,共11页
Background: Liver abscess (LA) is a suppurated collection in the hepatic parenchyma. In Africa, liver abscesses are most often of amoebic origin, but more recently, the rate of pyogenic liver abscesses (PLA) has incre... Background: Liver abscess (LA) is a suppurated collection in the hepatic parenchyma. In Africa, liver abscesses are most often of amoebic origin, but more recently, the rate of pyogenic liver abscesses (PLA) has increased. Objective: to assess the epidemiological characteristics, clinical features, biological radiological findings, and outcomes of patients with PLA and with amebic liver abscess (ALA) in order to determine the potential factors that may help improve diagnosis and treatment for LA in the context of secondary care centers with limited medical supports. Methods: Retrospective review of LA diagnosed and treated at three secondary care centers in Thiès over 11 years. Results: 61 patients, were included, 52.45% had ALA and 47.54% had PLA. Males were predominant (79.31% in PLA vs 65.63% in ALA, p = 0.2). The median age was 38 years for the PLA group vs 39 years for the ALA group (p = 0.4). In both groups, the most common symptom was right upper abdominal pain (81.97%), hepatomegaly (81.97%). The PLA group had a higher prevalence of fever (79.31% vs 46.88%, p = 0,009), chills (51.72% vs 18.75%, p = 0.007), right basi-thoracic pain (55.17% vs 28.13%, p = 0.032), and jaundice (55.17% vs 28%, p = 0.032). There was no difference in radiological features between PLA and ALA. Patients with PLA had a higher level of White blood cell (20.600 vs 15.400, p = 0.014). The most common bacteria identified in PLA were Escherichia coli (58.8%). All patients had received antibiotic therapy, which was combined with aspiration puncture (37.3%), transcutaneous drainage (43.3%), and surgery (9.0%). Seven patients had received antibiotic therapy alone and all had amoebic abscesses. Elsewhere, the occurrence of complications was higher in PLA cases (75.86% vs 37.5%, p = 0.003). The overall hospital mortality rate was 13.11%, higher in cases of PLA (24.14% vs 3.13%, p = 0.022). Conclusion: Clinical and biological features were more severe in PLA. But radiological features cannot be used to distinguish between PLA and ALA. 展开更多
关键词 PROFILE Liver Abscess Amoebic PYOGENIC Senegal
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Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework
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作者 Jintao Zhang Xingling Shao +1 位作者 Wendong Zhang Zongyu Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期278-287,共10页
This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the fe... This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution. 展开更多
关键词 Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following
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Radical Hysterectomy in Cervical Cancer: Patients’ Epidemiological and Clinical Profiles and Perioperative Outcome in Two Referral Hospitals in Cameroon
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作者 Théophile Njamen Nana Robert Tchounzou +16 位作者 Fulbert Nkwele Mangala Alphonse Ngalame Henri Essome Sedrick Tiokeng Sidonie Noa Ananga Andrew Tassang Humphry Tatah Neng Isaac Mboh Eyong Gaetan Andre Wambo Simo Felix Adolphe Elong Fidelia Kobenge Mbi Junior Cédric Nana Njamen Charlotte Tchente Nguefack Thomas Obinchemti Egbe Gregory Ekane Halle Emile Telesphore Mboudou Marcellin Ngowe Ngowe 《Open Journal of Obstetrics and Gynecology》 2024年第3期466-479,共14页
Background: Cervical cancer (CC) is one of the most frequent cancers and the leading cause of death from gynecological cancer in Low and middle income countries, Cameroon inclusive. Surgery is the primary treatment mo... Background: Cervical cancer (CC) is one of the most frequent cancers and the leading cause of death from gynecological cancer in Low and middle income countries, Cameroon inclusive. Surgery is the primary treatment modality when the disease is diagnosed at early stage. Radical hysterectomy in cervical cancer has not been evaluated in recent years in Cameroon. The purpose of this study is thus to evaluate the epidemiological and clinical features and short term outcomes of patients who underwent surgery. Patients and methods: This retrospective study was conducted at the Douala Gynaeco-obstetric and Pediatric Hospital and the Douala General Hospital. Cervical cancer patients who underwent Radical hysterectomy between January 2015 and December 2020 were included. A pre-established data collection tool was used to record socio-demographic, clinical and outcomes information from patients’ files;additional outcome information was obtained from phone calls. Descriptive analysis was done using the SPSS version 26. Bivariate analysis was used to determine associations between disease and patients characteristics and occurrence of adverse postoperative outcome. P value of 0.05 was considered. Results: Sixty one patients were enrolled. Their ages ranged from 33 to 74 years with a mean age of 51.95 ± 10.29 years. Over 85% of women were married, 65.57% were unemployed and 86.88% were multiparous. Only 28% had never done cervical cancer screening. Most patients had stage IB1 to IB2 stage disease (57.1%). Less than 9% underwent radical hysterectomy and 8 of those (13.11%) suffered intraoperative complications. Twenty-five patients (40.98%) presented immediate and short term complications. There was no significant association between the disease or patients’ characteristics and adverse outcomes. Conclusion: Cervical cancer patients are relatively young in our settings and only 9% of them reach the hospital at early stage. Postoperative adverse outcomes rate is higher than that reported in the literature. Sensitization on screening and awareness of early symptoms can reverse the situation. 展开更多
关键词 Cervical Cancer Radical Hysterectomy Epidemiological and Clinical profiles OUTCOMES Cameroon
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Profiles of the Headspace Volatile Organic and Essential Oil Compounds from the Tunisian Cardaria draba (L.) Desv. and Its Leaf and Stem Epidermal Micromorphology
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作者 Wissal Saadellaoui Samiha Kahlaoui +6 位作者 Kheiria Hcini Abir Haddada Noomene Sleimi Roberta Ascrizzi Guido Flamini Fethia Harzallah-Skhiri Sondes Stambouli-Essassi 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期725-744,共20页
In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total... In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatileorganic compounds (96.7%–98.9%) were identified;4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones,1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the maingroup, representing 49.5%–84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane(44.5%–76.2%) reaching the highest relative percentages. Forty-two compounds were determined in thetwo fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal componentswere hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl-2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermisusing light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces andnearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes wereanisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandulartrichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones wereidentified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatalindex (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essentialoil compounds can be used to characterize this species, and the various epidermis micromorphologicalfeatures are very useful for biosystematics taxonomic studies within Brassicaceae. 展开更多
关键词 Cardaria draba aroma profile essential oils EPIDERMIS TRICHOMES
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Co-inoculation of Debaryomyces hansenii and lactic acid bacteria: a strategy to improve the taste and odour profiles of dry sausages
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作者 Rongxin Wen Yumeng Sui +4 位作者 Jiaqi Liu Huiping Wang Baohua Kong Ligang Qin Qian Chen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3273-3283,共11页
The effects of the co-inoculation of Debaryomyces hansenii separately with 3 lactic acid bacteria(LAB),Lactobacillus sakei,Lactobacillus plantarum and Lactobacillus curvatus,on the taste and odour profi les of dry sau... The effects of the co-inoculation of Debaryomyces hansenii separately with 3 lactic acid bacteria(LAB),Lactobacillus sakei,Lactobacillus plantarum and Lactobacillus curvatus,on the taste and odour profi les of dry sausages were investigated.The co-inoculated sausages showed higher free amino acid and organic acid contents than the non-inoculated control and sausages inoculated with D.hansenii alone.Meanwhile,the sausages inoculated with D.hansenii+L.plantarum,D.hansenii+L.sakei and D.hansenii+L.curvatus had the highest contents of aldehydes,esters and alcohols,respectively.The results of electronic tongue,electronic nose and sensory evaluation demonstrated that compared with the sausage inoculated with D.hansenii,the sour taste and fl oral odour increased and the fatty odour decreased in the sausage inoculated with D.hansenii+L.sakei;this was more favourable for the development of a desirable fl avour in sausages.Moreover,the partial least squares regression analysis indicated that 10 taste and 33 odour compounds were mainly responsible for the differences in the flavour profiles among the sausages.Overall,these findings contributed to a more comprehensive understanding of the formation of sensory characteristics in dry sausages co-inoculated with yeast and LAB. 展开更多
关键词 Debaryomyces hansenii Lactic acid bacteria Dry sausage CO-INOCULATION Flavour profile
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Metabolic profiles and morphological characteristics of leaf tips among different sweet potato(Ipomoea batatas Lam.)varieties
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作者 Wenqing Tan Xinbo Guo +7 位作者 Zhangying Wang Rong Zhang Chaochen Tang Bingzhi Jiang Ruixue Jia Yuanyuan Deng Shaohai Yang Jingyi Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期494-510,共17页
Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their qualities.In this... Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their qualities.In this study,a UPLC-Q-Exactive Orbitrap/MS-based untargeted metabolomics method was used to evaluate the metabolites in leaf tips of 32 sweet potato varieties.Three varieties with distinct overall metabolic profiles(A01,A02,and A03),two varieties with distinct profiles of phenolic acids(A20 and A18),and three varieties with distinct profiles of flavonoids(A05,A12,and A16)were identified.In addition,a total of 163 and 29 differentially expressed metabolites correlated with the color and leaf shape of sweet potato leaf tips,respectively,were identified through morphological characterization.Group comparison analysis of the phenotypic traits and a metabolite-phenotypic trait correlation analysis indicated that the color differences of sweet potato leaf tips were markedly associated with flavonoids.Also,the level of polyphenols was correlated with the leaf shape of sweet potato leaf tips,with lobed leaf types having higher levels of polyphenols than the entire leaf types.The findings on the metabolic profiles and differentially expressed metabolites associated with the morphology of sweet potato leaf tips can provide useful information for breeding sweet potato varieties with higher nutritional value. 展开更多
关键词 sweet potato leaf tips phenotypic traits metabolic profile differentially expressed metabolites POLYPHENOLS
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The Effect of Blood Lipid Profiles on Chronic Kidney Disease in a Prospective Cohort:Based on a Regression Discontinuity Design
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作者 Kang Lyu Shaodong Liu +8 位作者 Yanli Liu Jinlong You Xue Wang Min Jiang Chun Yin Desheng Zhang Yana Bai Minzhen Wang Shan Zheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1158-1172,共15页
Objective Previous studies on the association between lipid profiles and chronic kidney disease(CKD)have yielded inconsistent results and no defined thresholds for blood lipids.Methods A prospective cohort study inclu... Objective Previous studies on the association between lipid profiles and chronic kidney disease(CKD)have yielded inconsistent results and no defined thresholds for blood lipids.Methods A prospective cohort study including 32,351 subjects who completed baseline and follow-up surveys over 5 years was conducted.Restricted cubic splines and Cox models were used to examine the association between the lipid profiles and CKD.A regression discontinuity design was used to determine the cutoff value of lipid profiles that was significantly associated with increased the risk of CKD.Results Over a median follow-up time of 2.2(0.5,4.2)years,648(2.00%)subjects developed CKD.The lipid profiles that were significantly and linearly related to CKD included total cholesterol(TC),triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),TC/HDL-C,and TG/HDL-C,whereas lowdensity lipoprotein cholesterol(LDL-C)and LDL-C/HDL-C were nonlinearly correlated with CKD.TC,TG,TC/HDL-C,and TG/HDL-C showed an upward jump at the cutoff value,increasing the risk of CKD by 0.90%,1.50%,2.30%,and 1.60%,respectively,whereas HDL-C showed a downward jump at the cutoff value,reducing this risk by 1.0%.Female and participants with dyslipidemia had a higher risk of CKD,while the cutoff values for the different characteristics of the population were different.Conclusion There was a significant association between lipid profiles and CKD in a prospective cohort from Northwest China,while TG,TC/HDL-C,and TG/HDL-C showed a stronger risk association.The specific cutoff values of lipid profiles may provide a clinical reference for screening or diagnosing CKD risk. 展开更多
关键词 Blood lipid profiles Chronic kidney disease Regression discontinuity design Prospective cohort
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Comparative study of cancer profiles between 2020 and 2022 using global cancer statistics(GLOBOCAN)
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作者 Wei Cao Kang Qin +1 位作者 Feng Li Wanqing Chen 《Journal of the National Cancer Center》 2024年第2期128-134,共7页
Background:The International Agency for Research on Cancer(IARC)released the latest estimates of the global burden of cancer.We present a comparison of cancer profiles between 2020 and 2022,leveraging data from the Gl... Background:The International Agency for Research on Cancer(IARC)released the latest estimates of the global burden of cancer.We present a comparison of cancer profiles between 2020 and 2022,leveraging data from the Global Cancer Statistics(GLOBOCAN).Methods:Cancer incidence and mortality data were sourced from two different years,2020 and 2022,in the GLOBOCAN database.We tracked changes in age-standardized incidence and mortality rates,as well as estimated numbers of new cancer cases and deaths of the 15 most common cancer types globally and in China between 2020 and 2022.Additionally,we conducted comparisons to assess alterations in the cancer burden and variations in mortality-to-incidence ratio(MIR)across different regions and countries for both 2020 and 2022.Results:Lung cancer remained the most common cancer and the leading cause of cancer death worldwide.The new cases of thyroid cancer witnessed a sharp increase in 2022.Conversely,the numbers of new cancer cases and deaths from stomach and esophageal cancer decreased significantly in 2022.The geographic distribution of cancer incidence and mortality across six continents in 2022 largely mirrored that of 2020.Higher Human Development Index(HDI)levels in countries corresponded with elevated rates of cancer incidence and mortality,consistent with the previous year.Among 185 countries or territories,China’s age-standardized incidence rate(ASIR)ranked 64th and its age-standardized mortality rate(ASMR)ranked 68th,aligning with global averages.Lung cancer continued to impose the greatest burden of incidence and mortality.Stomach,breast,and esophageal cancers showed declines in both case counts and ASIR.Noteworthy reductions in both ASMR and absolute mortality numbers were observed in liver,stomach,and esophageal cancers.The global MIR decreased from 0.516 in 2020 to 0.488 in 2022.MIR trends indicated an upward trajectory with decreasing HDI levels in both 2022 and 2020.While Canada,Germany,India,Italy,Japan,and the United Kingdom demonstrated increasing MIRs,China exhibited the most significant decrease,followed by Russia and the United States.Conclusions:The global landscape of cancer incidence and mortality in 2022 reflects ongoing trends observed in 2020.Cancer burdens vary notably across countries with differing socioeconomic statuses.Decreases in stomach,liver,and esophageal cancer cases and deaths signify progress in cancer control efforts.The decrease in the global MIRs highlights potential improvements in cancer management. 展开更多
关键词 GLOBOCAN Cancer profile WORLDWIDE China
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利用Red重组系统对大肠杆菌ClpP基因的敲除 被引量:29
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作者 白光兴 孙志伟 +1 位作者 黄莺 俞炜源 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2005年第1期35-38,共4页
利用含有质粒pKD4 6的菌株BW2 5 113,在阿拉伯糖诱导后 ,表达λ噬菌体的 3个重组蛋白 ,宿主菌就具有了同源重组的能力 .设计的引物 5′端有 5 0bp的拟敲除基因的同源臂 ,3′端为扩增引物 ,以pKD3为模板 ,扩增两侧含FRT位点的氯霉素抗性... 利用含有质粒pKD4 6的菌株BW2 5 113,在阿拉伯糖诱导后 ,表达λ噬菌体的 3个重组蛋白 ,宿主菌就具有了同源重组的能力 .设计的引物 5′端有 5 0bp的拟敲除基因的同源臂 ,3′端为扩增引物 ,以pKD3为模板 ,扩增两侧含FRT位点的氯霉素抗性基因 ,将此线性片段电转入具重组功能的感受态细胞 ,利用氯霉素平板就可以筛选到阳性转化体 .再利用表达Flp重组酶的质粒pCP2 0 ,可将FRT位点之间的氯霉素抗性基因删除 .利用该重组系统 ,构建了ClpP蛋白酶缺失的大肠杆菌工程菌株 ,可望在减少外源蛋白的降解方面发挥一定的作用 . 展开更多
关键词 clpp FLP重组酶 FRT位点 Red重组酶
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地震宽角反射/折射方法发展述评
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作者 王夫运 田晓峰 刘汉奇 《地球与行星物理论评(中英文)》 2025年第2期118-130,共13页
本文从地震宽角反射/折射方法的仪器装备、观测系统、观测实验、震相识别、数据分析等主要技术环节的出现、改进、发展、完善,回顾了该方法的百年发展历史.按照我们的见解,将其发展过程分为萌芽期、诞生期、成长期和发展期.对于早期的追... 本文从地震宽角反射/折射方法的仪器装备、观测系统、观测实验、震相识别、数据分析等主要技术环节的出现、改进、发展、完善,回顾了该方法的百年发展历史.按照我们的见解,将其发展过程分为萌芽期、诞生期、成长期和发展期.对于早期的追溯,重点放在方法的孕育和诞生起到关键作用的人物和事件上,并且尽可能详细;对后期的回顾,聚焦在方法的技术内容的萌发、出现、改进、应用和重点文献等方面,如,何时出现了剖面方法、相遇和追逐观测、地震宽角反射/折射剖面数据的完备性等,成果表述不作为重点,而且叙述简略.述及了天然地震学、地震折射勘探、地震反射勘探、电子技术、通讯技术、测量技术、计算机技术、计算数学等相关学科的进步,对地震宽角反射/折射方法发展的促进作用.展望未来,宽角反射/折射方法在我国深部探测与矿产资源勘查领域大有可为.以此文致敬追寻科学真理的地学前辈. 展开更多
关键词 地震宽角反射/折射方法 轻便地震仪 观测系统 观测实验 资料分析
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肺炎链球菌毒力因子ClpP蛋白酶的体外表达及纯化 被引量:5
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作者 袁军 陈曜 +1 位作者 曹炬 尹一兵 《第三军医大学学报》 CAS CSCD 北大核心 2008年第18期1753-1755,共3页
目的构建ClpP原核表达载体,获取原核表达的ClpP蛋白分子。方法分离培养TIGR4型肺炎链球菌,获取其染色体DNA,采用基因体外重组的方法将完整的ClpP读码框克隆到pET-32a原核表达载体,并经测序鉴定,所表达的抗原蛋白用Western blot鉴定,镍... 目的构建ClpP原核表达载体,获取原核表达的ClpP蛋白分子。方法分离培养TIGR4型肺炎链球菌,获取其染色体DNA,采用基因体外重组的方法将完整的ClpP读码框克隆到pET-32a原核表达载体,并经测序鉴定,所表达的抗原蛋白用Western blot鉴定,镍柱纯化并透析复性,真空冷冻干燥保存。结果测序结果证实克隆的基因与GenBank中的序列相符,Western blot证实获得了ClpP融合蛋白。结论获得了高表达的重组抗原蛋白,经镍柱纯化后纯度可达90%以上。 展开更多
关键词 毒力因子 肺炎链球菌 clpp蛋白
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clpP基因缺陷对肺炎链球菌毒力表达降低的研究 被引量:4
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作者 张群 胥文春 +3 位作者 尹一兵 朱兴华 李有强 张雪梅 《第三军医大学学报》 CAS CSCD 北大核心 2009年第4期307-310,共4页
目的探索clpP基因缺陷对肺炎链球菌(Streptococcus pneumoniae,S.pn)毒力的影响。方法用长臂同源多聚酶链式反应(LFH-PCR)方法失活clpP基因,用PCR、Western blot鉴定缺陷菌株,通过RT-PCR分析自溶素(major autoly-sin A,lytA)、表面黏附A... 目的探索clpP基因缺陷对肺炎链球菌(Streptococcus pneumoniae,S.pn)毒力的影响。方法用长臂同源多聚酶链式反应(LFH-PCR)方法失活clpP基因,用PCR、Western blot鉴定缺陷菌株,通过RT-PCR分析自溶素(major autoly-sin A,lytA)、表面黏附A(pneumococcal surface adhesion A,psaA)、溶血素(pneumolysin,ply)和胆碱结合蛋白A(cholinebinding protein A,cbpA)的表达,并通过动物实验观察clpP基因缺陷株毒力改变情况。结果RT-PCR显示clpP缺陷株的4个毒力因子mRNA表达水平均低于野生菌,两者比较有统计学差异(P<0.05);小鼠毒力实验表明野生菌株半数致死时间为22h,而缺陷株半数致死时间为8d,两者比较有统计学差异(P<0.01);缺陷菌在小鼠体内被清除速度也显著快于野生菌株(P<0.05)。结论clpP基因缺陷使S.pn多种毒力因子表达减弱,毒力降低。 展开更多
关键词 肺炎链球菌 毒力因子 热休克蛋白 clpp基因
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ClpP粘膜免疫预防小鼠发生肺炎链球菌性肺炎和败血症 被引量:2
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作者 陈怡婷 曹炬 +3 位作者 李岱容 吴凯峰 尹楠林 尹一兵 《中国免疫学杂志》 CAS CSCD 北大核心 2009年第6期556-559,共4页
目的:肺炎链球菌毒力蛋白ClpP鼻腔粘膜免疫BALB/c小鼠,探讨其作为肺炎链球菌候选蛋白疫苗的价值。方法:利用制备的ClpP多克隆抗体,分析ClpP在肺炎链球菌表面表达情况;ClpP蛋白粘膜免疫小鼠,TIGR4型肺炎链球菌分别经腹腔和鼻腔攻击,分析... 目的:肺炎链球菌毒力蛋白ClpP鼻腔粘膜免疫BALB/c小鼠,探讨其作为肺炎链球菌候选蛋白疫苗的价值。方法:利用制备的ClpP多克隆抗体,分析ClpP在肺炎链球菌表面表达情况;ClpP蛋白粘膜免疫小鼠,TIGR4型肺炎链球菌分别经腹腔和鼻腔攻击,分析肺炎链球菌小鼠肺内定植情况并监测小鼠生存时间。结果:流式细胞技术证实了TIGR4肺炎链球菌表面表达ClpP毒力蛋白,粘膜免疫ClpP可以特异产生系统性和粘膜性的ClpP抗体,并可减少TIGR4肺炎链球菌在小鼠肺内的定植,延长小鼠生存时间。结论:ClpP粘膜免疫可预防小鼠发生肺炎链球菌性肺炎和败血症,进一步证实ClpP蛋白可作为肺炎链球菌的候选蛋白疫苗。 展开更多
关键词 粘膜免疫 肺炎链球菌 clpp
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牛种布鲁氏菌clpP基因缺失株的毒力和免疫保护力评价 被引量:3
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作者 彭小薇 吴方达 +6 位作者 刘郁夫 董浩 孙永健 毕一鸣 张存瑞 刘林青 韩焘 《中国动物检疫》 CAS 2019年第11期59-64,共6页
为研究布鲁氏菌clpP基因与细菌毒力的关系,采用同源重组的方法,构建牛种布鲁氏菌clpP基因缺失株,用巨噬细胞RAW264.7感染模型和小鼠感染模型评价clpP基因缺失株的毒力,同时测定该缺失株免疫小鼠后产生的免疫保护力。研究发现:牛种布鲁氏... 为研究布鲁氏菌clpP基因与细菌毒力的关系,采用同源重组的方法,构建牛种布鲁氏菌clpP基因缺失株,用巨噬细胞RAW264.7感染模型和小鼠感染模型评价clpP基因缺失株的毒力,同时测定该缺失株免疫小鼠后产生的免疫保护力。研究发现:牛种布鲁氏菌clpP基因缺失后,在细胞感染模型和小鼠感染模型中的毒力显著降低;clpP基因缺失株感染小鼠后,不引起脾脏肿胀,并且在脾脏内的持续期短于A19疫苗株,说明该基因缺失株具有更高的安全性;使用clpP基因缺失株免疫小鼠后,该基因缺失株无法抵御牛种布鲁氏菌2308株和羊种布鲁氏菌M28株的感染。本研究为揭示布鲁氏菌致病机制和新型布病疫苗研发提供了参考。 展开更多
关键词 布鲁氏菌 疫苗 clpp基因 毒力 基因缺失株 免疫保护
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肺炎链球菌候选蛋白疫苗ClpP的保守性和抗原性 被引量:2
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作者 李岱容 曹炬 +2 位作者 王虹 吴凯峰 尹一兵 《第四军医大学学报》 北大核心 2008年第19期1741-1744,共4页
目的:评价酪蛋白裂解酶P(ClpP)作为候选疫苗的保守性和抗原性,分析在不同血清型肺炎链球菌(SPN)中的表达情况.方法:以TIGR4型SPN的ClpP基因序列设计引物,分别以12株不同血清型SPN的基因组DNA为模板,对ClpP基因进行聚合酶链反应(PCR)扩... 目的:评价酪蛋白裂解酶P(ClpP)作为候选疫苗的保守性和抗原性,分析在不同血清型肺炎链球菌(SPN)中的表达情况.方法:以TIGR4型SPN的ClpP基因序列设计引物,分别以12株不同血清型SPN的基因组DNA为模板,对ClpP基因进行聚合酶链反应(PCR)扩增、胶回收产物与PMD-18克隆载体连接后进行测序,运用生物信息学方法对其核苷酸及推测的氨基酸序列及抗原性进行分析,并利用West-ernBlot方法检测12株不同血清型SPN的ClpP蛋白的表达情况.结果:12株不同血清型SPN的ClpP基因序列和Gen-Bank数据库对已公布的TIGR4型SPN的ClpP基因一致性>99.0%,推测的氨基酸序列一致性>99.5%.WesternBlot结果显示anti-ClpP多克隆抗体与12型SPN的菌体蛋白能够起交叉反应.结论:ClpP蛋白在不同型SPN之间同源性高,在不同型SPN菌株中均有表达.ClpP是一个具有前景的SPN候选蛋白疫苗因子. 展开更多
关键词 肺炎链球菌 clpp基因 序列分析 抗原性
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铜绿假单胞菌clpP基因缺陷株的构建 被引量:1
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作者 张加勤 饶慧华 +4 位作者 徐巧丽 黄朝阳 房丽丽 马晓波 宋秀宇 《中国人兽共患病学报》 CAS CSCD 北大核心 2015年第7期627-630,共4页
目的构建铜绿假单胞菌clpP基因缺陷株。方法分别以质粒pUCGM和铜绿假单胞菌PAO1基因组为模板PCR扩增庆大霉素抗性基因(GM)和铜绿假单胞菌clpP基因及其3′、5′侧翼序列,将clpP基因及其3′、5′侧翼序列克隆至pMD19T载体,EcoRV切除clpP基... 目的构建铜绿假单胞菌clpP基因缺陷株。方法分别以质粒pUCGM和铜绿假单胞菌PAO1基因组为模板PCR扩增庆大霉素抗性基因(GM)和铜绿假单胞菌clpP基因及其3′、5′侧翼序列,将clpP基因及其3′、5′侧翼序列克隆至pMD19T载体,EcoRV切除clpP基因37bp^453bp片段后,引入庆大霉素抗性基因,构建重组质粒pCKR2;EcoRⅠ/HindⅢ双酶切重组质粒pCKR2,回收FclpP-GM-clpPR片段,与自杀质粒pEX18Tc连接,得到clpP基因缺陷的同源重组载体pCKR3;将pCKR3质粒转化大肠埃希菌SM10,与铜绿假单胞菌PAO1双亲杂交,庆大霉素筛选得到铜绿假单胞菌clpP基因缺陷株。结果经酶切鉴定同源重组载体pCKR3构建正确;PCR和DNA测序鉴定铜绿假单胞菌clpP基因缺陷株构建成功。结论本研究成功敲除了铜绿假单胞菌clpP基因,为进一步研究clpP基因的生物学功能奠定了基础。 展开更多
关键词 铜绿假单胞菌 clpp基因 双亲杂交 同源重组
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胡萝卜软腐果胶杆菌clpP基因的功能研究 被引量:1
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作者 李婷 蒋欢 +4 位作者 杨钟灵 邓亚岷 杜硕 刘凤权 范加勤 《南京农业大学学报》 CAS CSCD 北大核心 2013年第2期58-64,共7页
为探索clpP基因对胡萝卜软腐果胶杆菌胡萝卜亚种(Pectobacterium carotovorum subsp.carotovorum,P.c.c)生物学特性及致病性等方面的影响,采用同源重组法构建clpP基因缺失突变体ΔclpP和互补菌株ΔclpP(clpP),测定突变体及互补菌株的运... 为探索clpP基因对胡萝卜软腐果胶杆菌胡萝卜亚种(Pectobacterium carotovorum subsp.carotovorum,P.c.c)生物学特性及致病性等方面的影响,采用同源重组法构建clpP基因缺失突变体ΔclpP和互补菌株ΔclpP(clpP),测定突变体及互补菌株的运动性、生物膜、抗氧化压力,以及在不同培养基和不同温度下的生长能力、部分致病因子活性及致病性等表型,并采用RT-PCR分析了果胶酸裂解酶(Pel)、纤维素酶(Cel)、蛋白酶(Prt)和坏死诱导蛋白(necrosis-inducing protein,Nip)等相关致病因子的编码基因转录水平变化。结果表明:ΔclpP的运动性无变化,生物膜形成、高温和营养饥渴耐受力及抗氧化压力等均下降;果胶酶、纤维素酶与蛋白酶活性有不同程度降低,酶活性检测平板上水解圈的直径分别比野生株下降19.35%、34.38%和35.00%;ΔclpP的致病性显著下降,离体接种‘黄花马蹄莲’叶片和大白菜叶柄,病斑面积分别比野生株的减小99.00%和99.60%;在4个毒力因子中,qRT-PCR显示:ΔclpP果胶酸裂解酶与纤维素酶mRNA相对表达量为野生菌株的40.00%左右。由此可见,clpP基因对胡萝卜软腐果胶杆菌的生长和致病性具有多方面的决定作用。 展开更多
关键词 胡萝卜软腐果胶杆菌胡萝卜亚种 clpp 生物学特性 致病性
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利用Red重组系统敲除大肠杆菌菌株ClpP基因方法的研究 被引量:1
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作者 司微 刘慧芳 +9 位作者 王春来 彭玮 赫明雷 杜艳芬 赵海玲 王聃 杨金国 林靖凯 倪洪波 刘思国 《黑龙江畜牧兽医》 CAS 北大核心 2011年第8期28-30,共3页
为了研究ClpP基因的功能,试验利用Red系统的重组功能,通过PCR扩增出两端与大肠杆菌菌株ClpP基因上、下游序列同源,中间为氯霉素抗性基因cat的DNA片段,电击转化含质粒pKD46的大肠杆菌菌株DH091,筛选替换ClpP基因的阳性转化子,再导入质粒p... 为了研究ClpP基因的功能,试验利用Red系统的重组功能,通过PCR扩增出两端与大肠杆菌菌株ClpP基因上、下游序列同源,中间为氯霉素抗性基因cat的DNA片段,电击转化含质粒pKD46的大肠杆菌菌株DH091,筛选替换ClpP基因的阳性转化子,再导入质粒pCP20去除氯霉素抗性基因。结果表明:成功敲除大肠杆菌菌株ClpP基因。 展开更多
关键词 RED重组系统 clpp基因 基因敲除
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结核分枝杆菌ClpP1重组蛋白的特性探讨及初步应用 被引量:1
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作者 张春燕 杨春 +3 位作者 李岱容 穆柳青 樊宇 何永林 《免疫学杂志》 CAS CSCD 北大核心 2014年第4期306-309,313,共5页
目的用纯化结核分枝杆菌(Mycobacterium tuberculosis,M.tb)ClpP1重组蛋白免疫新西兰白兔制备ClpP1多克隆抗体并检测其效价,间接ELISA法分析重组蛋白的抗原性,以初步评价其应用价值。方法通过SDS-PAGE确定ClpP1重组蛋白的主要表达形式,... 目的用纯化结核分枝杆菌(Mycobacterium tuberculosis,M.tb)ClpP1重组蛋白免疫新西兰白兔制备ClpP1多克隆抗体并检测其效价,间接ELISA法分析重组蛋白的抗原性,以初步评价其应用价值。方法通过SDS-PAGE确定ClpP1重组蛋白的主要表达形式,利用纯化包涵体方式对重组蛋白进行纯化;将纯化蛋白免疫新西兰白兔制备ClpP1多克隆抗体并检测其效价;再分别以纯化蛋白为抗原,制备抗体为一抗,间接ELISA法检测临床诊断结核病患者血清中抗M.tb抗体和M.tb抗原。结果 SDSPAGE显示ClpP1重组蛋白主要以包涵体表达形式存在,将纯化蛋白免疫新西兰白兔4次,取血测抗体效价为1∶64 000;Western blot结果显示制备抗体可较好的与ClpP1蛋白特异性结合;间接ELISA法结果表明,以重组蛋白为抗原测患者血清中抗M.tb抗体和以制备抗体为一抗测血清中的M.tb抗原的2实验组分别与对照组相比均具有显著性差异。结论制备了具有免疫原性的M.tb ClpP1重组蛋白及效价较高的多克隆抗体,并得出ClpP1多克隆抗体具有较好的免疫反应性,为进一步研究ClpP1重组蛋白的特性及其应用奠定了基础。 展开更多
关键词 结核分枝杆菌 clpp1重组蛋白 多克隆抗体
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