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2型猪链球菌天津分离株的鉴定及其遗传特征分析 被引量:1
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作者 董志民 李秀丽 +10 位作者 杨春蕾 杨丽景 田向学 王利丽 池晶晶 张莉 孟乐 张万江 祝瑶 张东超 鄢明华 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第5期468-475,共8页
为了解天津市某猪场引起育肥猪神经症状的病原及其特性和遗传特征,本研究采集8份患病猪脑组织样品经细菌分离、形态学观察、gdh基因和cps2J基因的PCR扩增及序列分析,确定8份样品中的分离株均为同一2型猪链球菌(SS2),命名为TJS75。测定... 为了解天津市某猪场引起育肥猪神经症状的病原及其特性和遗传特征,本研究采集8份患病猪脑组织样品经细菌分离、形态学观察、gdh基因和cps2J基因的PCR扩增及序列分析,确定8份样品中的分离株均为同一2型猪链球菌(SS2),命名为TJS75。测定其生长曲线、并按照文献方法进行溶血性试验、黏附/侵入试验和对小鼠的致病性试验,分析该SS2分离株特性。结果显示,TJS75菌株经TSB培养6 h~15 h可达对数生长期,对绵羊血红细胞(RBC)具有崩解效果,可黏附并侵入PK-15细胞(黏附率和侵袭率分别为5.16%和7.90%),且感染TJS75株的BALB/c小鼠出现不同程度的行动迟缓、呼吸急促、精神萎靡和神经症状等,经测定其LD50为2.15×107cfu/mL。进一步采用高通量测序,并预测其毒力基因,分析该菌株的遗传特征,结果显示,TJS75菌株基因组全长2368195 bp,GC含量40.88%,含有2299个编码基因,其中有1822、1830和1077个基因分别注释于GO、COG和KEGG数据库,携带的16S r RNA基因序列与国内分离的SS强毒株98HAH33和05ZYH33的亲缘性较近,毒力基因的预测结果显示该菌株携带499种毒力相关基因(编码173种毒力相关因子),依据功能分类,这些毒力基因参与SS2的黏附和侵袭、溶血、促进铁转运、自溶酶的合成、降解胶原酶、唾液酸的合成等。本研究首次分离到携带MRP毒力因子的ST25型SS2,为深入开展SS2 TJS75株的致病机制研究提供了科学依据。 展开更多
关键词 猪链球菌2 分离鉴定 致病力 遗传特征
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老年2型糖尿病患者社会隔离发生现状及其影响因素 被引量:3
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作者 王静 刘宇 +3 位作者 张文娟 林可可 白小燕 赵欣然 《军事护理》 CSCD 北大核心 2024年第5期15-18,72,共5页
目的了解老年2型糖尿病(type 2 diabetes mellitus,T2DM)患者社会隔离发生现状及影响因素。方法使用问卷调查2023年5-8月在北京市医院或社区医院就诊的老年T2DM患者的社会隔离现状;采用Logistic回归分析总体及各维度社会隔离发生的影响... 目的了解老年2型糖尿病(type 2 diabetes mellitus,T2DM)患者社会隔离发生现状及影响因素。方法使用问卷调查2023年5-8月在北京市医院或社区医院就诊的老年T2DM患者的社会隔离现状;采用Logistic回归分析总体及各维度社会隔离发生的影响因素。结果397例老年T2DM患者中189例发生社会隔离,发生率为47.61%,其中家庭维度、朋友维度社会隔离的发生率分别为15.11%、49.37%。女性、退休、自理障碍、认知障碍、孤独感及中水平社会参与为社会隔离的危险因素,吸烟与中/高水平社会支持为保护因素(均P<0.05)。结论老年T2DM患者社会隔离发生率较高,朋友维度社会隔离发生率高于家庭维度。需关注女性、退休、有自理障碍、认知障碍、孤独感、低水平社会支持与社会参与的患者,采取措施减少其社会隔离的风险。 展开更多
关键词 2型糖尿病 老年 社会隔离 影响因素
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Isolation, Identification and Pathogenicity Analysis of Streptococcus suis Type 2 被引量:4
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作者 Zicheng MA Yan LI +6 位作者 Jinyuan GU Tao PENG Zhaohu LIU Hongyu WANG Fanliang MENG Fangkun WANG Sidang LIU 《Agricultural Biotechnology》 CAS 2019年第4期64-68,共5页
[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determinati... [Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determination of growth curve and correlation curve between OD 600 values and viable counts,drug susceptibility tests,pathogenicity analysis,and histopathological observations were carried out.[Results]The Streptococcus strain isolated from infected pigs was identified as Streptococcus suis type 2,which was named TA01 strain.TA01 strain reached the growth peak at 6-8 h post-incubation,and viable counts gradually declined after 8 h of incubation.The correlation equation between OD 600 values and viable counts is y=24.659 x-1.076 1,R^2=0.996 7.TA01 strain was sensitive to penicillin,erythromycin,florfenicol and oxacillin,and resistant to ciprofloxacin,polymyxin B and clindamycin.According to the results of pathogenicity analysis,all the mice in 3.6×10^9 cfu/mouse group died within 48,and these dead mice exhibited acute pyaemia septica.Based on the Reed-Muench formula,it was calculated that LD 50 of TA01 strain was 1.137×10^8 cfu/mouse.Pathological examination showed obvious blue-stained bacteria clusters,accompanied by neutrophil infiltration.[Conclusions]TA01 strain was a virulent strain of Streptococcus suis type 2.Compared with Streptococcus strains which were isolated and reported in China,TA01 strain exhibited strong virulence and rapid proliferation. 展开更多
关键词 STREPTOCOCCUS SUIS TYPE 2 isolation and IDENTIFICATION Growth curve Drug sensitivity test PATHOGENICITY LD 50 determination
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Isolation and Identification of a Specific cDNA Mapping to the Bam HI-I2 and -LFragments within the Inverted Repeats ofUnique Long Re-gion (IRL) in the Genom e ofMarek′s Disease Herpesvirus (MDV) Oncogenic Strain Beijing-1 被引量:13
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作者 Lu Chun, Wu Jianping, Zhang Xunhai, et al. Lu Chun, Wu Jianping, Zhang Xunhai, et al. Department of Microbiology and Immunology, Nanjing Medical University, Nanjing\ 210029 Acta Universitatis Medicinalis Nanjing, 19(6):447 《The Journal of Biomedical Research》 CAS 1999年第2期73-73,共1页
Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 ... Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors. 展开更多
关键词 CDNA IRL in the Genom e ofMarek isolation and Identification of a Specific cDNA Mapping to the Bam HI-I2 and LFragments within the Inverted Repeats ofUnique Long Re-gion Oncogenic Strain Beijing-1 s Disease Herpesvirus LONG RE MDV
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High efficient Sr/S isolation for preparing Sr(OH)_2 from celestite(SrSO_4) in alkaline solution 被引量:1
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作者 CHEN Si-ming DUAN Dong-ping +3 位作者 LIU Yan ZHOU E HAN Hong-liang ZOU Xing-wu 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第1期219-228,共10页
The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency.Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestit... The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency.Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestite in mild condition was described.Sr element remained in precipitation with formation of Sr(OH)2,while S element entered into leachate with formation of Na2SO4.The effects of initial concentration of NaOH,conversion temperature,liquid-to-solid(L/S)ratio and conversion time on Sr/S ratio of samples for celestite conversion were systematically investigated by experiments.The results demonstrated that the efficiency of Sr/S isolation increased with the initial concentration of NaOH,L/S ratio and conversion time,and decreased with conversion temperature.The maximum conversion ratio of Sr(OH)2 was 93.88%under the optimum condition,whose Sr/S ratio of sample could reach to 41.16.It illustrated that better isolation efficiency of celestite could be achieved in alkaline treatment.The results of SEM-EDS analyses demonstrated that the conversion reaction was a dissolution-precipitation process. 展开更多
关键词 CELESTITE Sr(OH)2 high efficient Sr/S isolation dissolution-precipitation process
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Isolation of 2-Chloro-5-methylpyridine from its Isomer 2-Chloro-3-methylpyridine by Formation of its Copper(II) Complex
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作者 RiChengXUAN WeiXiaoHU ZhongYuYANG YaPingLU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第2期181-182,共2页
Chloro-5-methylpyridine can be effectively isolated from its isomer 2-chloro-3- methyl-pyridine in the form of Cu2+complex. After hydrolyzing the complex, it can be obtained in more than 99.1% purity.
关键词 isolation 2-chloro-5-methylpyridine.
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Isolation and Crystal Structure of 4β,6α,9α-Trimethy-2-carboxyltricyclo[6.3.0.0^(4,5)]undec-2-ene
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作者 施树云 吴迪瑶 赵昱 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第9期1045-1048,共4页
The title compound, 4β,6α,9α-trimethy-2-carboxyltricyclo[6.3.0.0^(4,5)]undec-2-ene, is a sesquiterpene which was first isolated from Ligularia caloxantha and characterized by MS and NMR. In addition, the structur... The title compound, 4β,6α,9α-trimethy-2-carboxyltricyclo[6.3.0.0^(4,5)]undec-2-ene, is a sesquiterpene which was first isolated from Ligularia caloxantha and characterized by MS and NMR. In addition, the structure was determined by X-ray single-crystal diffraction. It crystallizes in orthorhombie, space group P212121 with a = 8.197(2), b = 14.876(3), c = 22.281(6) A, α = β = γ = 90°, V = 2716.9(11) ]A^3, Z = 8, C15H22O2, Mr = 234.34, Dc = 1.146 g/cm^3, μ(MoKa) = 0.074 mm^-1, F(000) = 1024, the final R = 0.0384 and wR = 0.0856 for 6200 independent reflections (Rint = 0.066) and 2538 observed ones (I 〉 2σ(I)). In the molecule, there are three fused five-membered rings; while in this crystal form, the asymmetric unit contains two molecules of the same hand and they are linked together by two intermolecular O-H...O hydrogen bonds to form a dimer. 展开更多
关键词 Ligularia caloxantha isolation crystal structure 9α.trimethy-2-carboxyltricyclo[6.3.0.0^(4 5)]undec-2-ene
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Isolation and Identification of Canine Parvovirus Serotype 2a and Its VP2 Protein Expression in Transgenic Tobacco
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作者 Ning XIONG Yong ZHANG +3 位作者 Yao WANG Bao-yu YANG1 and Shi-yun CHEN Bao-yu YANG Shi-yun CHEN 《Virologica Sinica》 SCIE CAS CSCD 2008年第3期203-210,共8页
A strain of canine parvovirus(CPV)was isolated from feces of an ill puppy in an animal hospital in Wuhan, China. It was designated as CPV/WH02/06. This isolate was identified as serotype CPV-2a by the hemagglutination... A strain of canine parvovirus(CPV)was isolated from feces of an ill puppy in an animal hospital in Wuhan, China. It was designated as CPV/WH02/06. This isolate was identified as serotype CPV-2a by the hemagglutination test, CPV Ag detection strip, electron microscopy, and PCR. The vp2 gene was cloned and sequenced and assigned GenBank accession number EU377537. A 1242 bp segment of the 5' region of the vp2 gene was cloned and inserted into the binary vector pBI121 and used for Agrobacterium-mediated tobacco transformation. Transgenic tobacco plants were selected on MS medium supplemented with 100 μg/mL kanamycin and 100 μg/mL timentin. Integration of the vp2 gene into the tobacco genome was confirmed by PCR using T1 progeny plants, and the expression of the VP2 protein was confirmed by Western blotting. 展开更多
关键词 Canine parvovirus isolation VP2 TOBACCO EXPRESSION
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Isolation and Identification of Porcine Circovirus Type 2 in Taizhou
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作者 Guangfu GUO Aiping ZHU +3 位作者 Junping CAO Cailian JIN Lihong DAI Hongwei TAO 《Agricultural Biotechnology》 CAS 2018年第4期108-109,249,共3页
In September 2011, an infectious disease suspected to be postweaning multisystemic wasting syndrome (PMWS) broke out in some pig farm in Taizhou. The inguinal lymph node, liver and lung tissues were collected and gr... In September 2011, an infectious disease suspected to be postweaning multisystemic wasting syndrome (PMWS) broke out in some pig farm in Taizhou. The inguinal lymph node, liver and lung tissues were collected and grinded into tissue suspension. The suspension was subjected to PCR detection, and the positive product was sequenced. The suspension of positive samples was filtered with 0.22 μm filter membrane, and the filtrate was inoculated onto PK15 cells. After five generations of blind passages, the cell viral liquid was collected and extracted for DNA, which was subjected to PCR detection and indirect immunofluorescence. The results showed that the isolate was porcine circovirus type 2 (PCV2) and designated as TAIZ110926. The target sequence was committed to NCBI with a serial number: KF039888. 展开更多
关键词 Porcine circovirus type 2 isolation IDENTIFICATION Target sequence
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犬腺病毒2型的分离鉴定和致病性分析
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作者 刘彩红 崔宁宁 +4 位作者 陈亚磊 廖均乐 朱进华 刘玉秀 田克恭 《中国兽医杂志》 CAS 北大核心 2024年第3期9-17,共9页
为了解湖北省犬腺病毒2型(CAV-2)的基因遗传变异特征,本试验从武汉市某比格犬养殖场采集免疫过犬四联活疫苗的临床发病犬的眼、鼻和肛拭子,将经PCR检测为CAV-2阳性的病料接种犬肾细胞(MDCK细胞)进行病毒分离,对CAV-2分离株进行电子显微... 为了解湖北省犬腺病毒2型(CAV-2)的基因遗传变异特征,本试验从武汉市某比格犬养殖场采集免疫过犬四联活疫苗的临床发病犬的眼、鼻和肛拭子,将经PCR检测为CAV-2阳性的病料接种犬肾细胞(MDCK细胞)进行病毒分离,对CAV-2分离株进行电子显微镜观察和间接免疫荧光鉴定,E3、Fiber、Penton和E1b基因PCR扩增和测序分析以及致病性试验。结果显示:经分离和鉴定共获得3株CAV-2,分别命名为HB404株、HB405株和HB078株。3株CAV-2分离株的E3、Fiber、Penton和E1b基因与国外疫苗毒株相似性分别为98.4%~99.6%、99.3%~99.9%、99.8%~99.9%和99.5%~99.7%;3株分离株的E3、Fiber和Penton基因与国内流行毒株相似性分别为96.6%~97.5%、98.5%~99.7%和99.4%~99.9%。且3株CAV-2分离株与国外疫苗毒株在同一分支,与国内流行毒株不在同一分支。HB405株能使犬出现精神不振、食欲减退、眼鼻有分泌物、打喷嚏和咳嗽等临床症状。结果表明,3株分离株的亲缘关系与国外疫苗毒株较近,HB405株为强毒株,能够使犬发病。本试验结果可为CAV-2的诊断和预防提供参考依据。 展开更多
关键词 犬腺病毒2 基因测序 分离鉴定 致病性
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Isolation and Identification of Porcine Epidemic Diarrhea Virus(PEDV) HLJ Strain with IPEC-J2 Cells and Phylogenetic Analysis of Its S Gene
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作者 Feng Rui Liu Hai-xin +4 位作者 Zhong Ming Li Xun-liang Huang Xiao-dan Ren Yu-dong Li Guang-xing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第4期63-72,共10页
Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resul... Porcine epidemic diarrhea(PED)is caused by porcine epidemic diarrhea virus(PEDV),and is characterized by vomiting,diarrhea and dehydration of suckling pigs from 80% to 100% morbidity and 50% to 90% mortality,and resulted in tremendous economic losses to swine industry.The PEDV mainly infects small intestine of pigs,resulting in vacuolar degeneration and necrosis of mucosal epithelium.The IPEC-J2 is a pig intestine epithelial cell line,which is similar to the intestinal environment of piglets,can be used to isolate and identify the PEDV field isolates.In this study,it appeared the PEDV typical postmortem changes and histopathological lesion of degeneration and destruction of small intestine in infected piglets,and IHC identified that the PEDV distributed in the mucosa and submucosa of small intestine mostly.Furthermore,the PEDV HLJ strain was successfully isolated and characterized in the IPEC-J2 cells,and indicated that the IPEC-J2 cell line was sensitive to isolate and adapt the PEDV field strain,and could be utilized to multiply the PEDV rapidly.The S gene analysis indicated that the PEDV HLJ strain was the prevailed virus,belonged to Group 1 with attenuated virulent DR13,SC1402 and J-S2/2015 strains isolated in South Korea and China from 2014 to 2015.This study had important theoretical and practical significances on analyzing genetic variation of the PEDV,understanding the pathogenic characteristics of the virus and developing new vaccines for the PED. 展开更多
关键词 porcine epidemic diarrhea virus cytopathic effect IPE-J2 cell isolation and identification phylogenetic analysis
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鮟鱇鱼皮活性肽的分离纯化及其对HK-2细胞损伤保护的作用
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作者 许珂 缪秉陶 +3 位作者 曹洪杰 任祥雨 李航婷 杨最素 《广东海洋大学学报》 CAS CSCD 北大核心 2024年第4期1-10,共10页
【目的】为探讨鮟鱇(Lophius litulon)鱼皮活性肽(Monkfish skin peptides,MSP)对棕榈酸(Palmitic acid,PA)诱导人肾皮质近曲小管上皮细胞(HK-2细胞)损伤保护的作用。【方法】以新鲜鮟鱇鱼皮为材料,选取加酶量、提取时间、pH、温度和料... 【目的】为探讨鮟鱇(Lophius litulon)鱼皮活性肽(Monkfish skin peptides,MSP)对棕榈酸(Palmitic acid,PA)诱导人肾皮质近曲小管上皮细胞(HK-2细胞)损伤保护的作用。【方法】以新鲜鮟鱇鱼皮为材料,选取加酶量、提取时间、pH、温度和料液比为因子,以1,1-二苯基-2-三硝基苯肼自由基(DPPH·)清除率为响应值,分别进行单因素实验和响应面实验,优化鮟鱇鱼皮肽的提取工艺;对得到的鮟鱇鱼皮肽经过超滤、葡聚糖凝胶过滤层析和全自动高压制备分离纯化得到MSP;利用液相二级质谱和多肽从头(de novo)测序技术对其进行结构分析,筛选抗氧化活性较强的肽段;通过构建PA诱导的HK-2细胞损伤模型,测定MSP对HK-2细胞中氧化应激指标、脂质代谢指标和炎症因子水平的影响。【结果】确定酸性蛋白酶与胃蛋白酶质量比2∶1的复配比例,加酶量3 800 U/g、pH 3、酶解时间4 h、温度50℃和料液比1 g∶10 mL为鮟鱇鱼皮活性肽的最佳酶解条件,此条件下制备的鮟鱇鱼皮肽对DPPH·的清除率为78.84%;经超滤,酶解多肽中<3 ku组分抗氧化活性最强,收集该组分进行凝胶色谱分离后,得到F1、F2和F3共3个峰,其中F1组分DPPH·清除率最高。F1组分经高效液相色谱法(HPLC)分离纯化后得到6个吸收峰,其中H2组分吸收峰强度最高,经氨基酸序列鉴定,从中筛选出3种寡肽,分别为Phe-Glu-Ala-Thr-Ser-Gln-Glu-Leu(FEATSQEL,FL-8)、Leu-Val-Ser-Cys-Ser-Ser-Leu(LVSCSSL,LL-7)和Pro-Leu-Glu-Asn-Tyr(PLENY,PY-5)。3条多肽在HK-2细胞脂质损伤模型中的修复作用各不相同:FL-8和PY-5能提高HK-2细胞模型的抗氧化能力,使细胞内谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)显著升高,降低细胞中活性氧的荧光强度,并显著降低丙二醛(MDA)水平,而LL-7能降低GSH-Px活性与T-AOC能力,能显著降低MDA的含量;在调节细胞的脂质代谢方面,FL-8与PY-5分别在不同程度上降低总胆固醇、甘油三酯和低密度脂蛋白-胆固醇含量,并显著增加高密度脂蛋白-胆固醇含量,而LL-7则会加剧细胞内的脂质蓄积;FL-8与PY-5显著降低炎症因子白细胞介素-18(IL-18)的水平,而LL-7则相反(α=0.05)。【结论】制备的MSP对PA诱导的HK-2具有保护作用,可为鮟鱇鱼皮活性肽的利用和缓解脂质肾毒性产品的开发提供理论基础和实验依据。 展开更多
关键词 鮟鱇鱼皮 活性肽 分离纯化 HK-2细胞 保护
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1株猪圆环病毒2型的分离与鉴定
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作者 程泽 李智 +4 位作者 王延辉 王文强 朱振邦 曲向阳 李向东 《畜牧与兽医》 CAS 北大核心 2024年第11期86-93,共8页
为了解广东省某规模猪场引起母猪繁殖障碍及仔猪死亡的主要病原,通过实验室检测病死仔猪肺脏及淋巴结样品中常见病原,发现存在猪圆环病毒2型(PCV2)的感染。对阳性样品进行全基因组扩增、测序后,与国内外其他PCV2毒株进行同源性比对,建... 为了解广东省某规模猪场引起母猪繁殖障碍及仔猪死亡的主要病原,通过实验室检测病死仔猪肺脏及淋巴结样品中常见病原,发现存在猪圆环病毒2型(PCV2)的感染。对阳性样品进行全基因组扩增、测序后,与国内外其他PCV2毒株进行同源性比对,建立系统遗传进化树并进行分析;通过猪肾细胞系进行病毒分离,使用荧光定量PCR及间接免疫荧光法对分离病毒进行鉴定。结果显示:分离的毒株GD-2为PCV2a基因型,基因组全长为1768 bp。与其他毒株相比,GD-2与H24-1-2019、E15-2-2019、F18-2-2019这3株PCV2毒株基因组同源性为99.9%。毒株GD-2经PK-15细胞系连续传代,第7代病毒滴度为10^(4.375)TCID_(50)/0.1 mL。本研究为广东地区PCV2的流行提供了新的数据信息。 展开更多
关键词 猪圆环病毒2 分离鉴定 进化分析
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2型糖尿病患者服药依从性现状与衰弱及主观社会隔离的相关性研究
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作者 杨丹 迟晨汝 +3 位作者 陈梦奇 周志庆 王翠珍 刘欢 《右江民族医学院学报》 2024年第3期380-384,共5页
目的调查芜湖市某三甲医院2型糖尿病患者服药依从性现状并分析其影响因素,了解2型糖尿病患者服药依从性与衰弱以及主观社会隔离的相关性,以期为提高2型糖尿病患者的服药依从性提供依据。方法采取方便抽样法在芜湖市某三甲医院内分泌、... 目的调查芜湖市某三甲医院2型糖尿病患者服药依从性现状并分析其影响因素,了解2型糖尿病患者服药依从性与衰弱以及主观社会隔离的相关性,以期为提高2型糖尿病患者的服药依从性提供依据。方法采取方便抽样法在芜湖市某三甲医院内分泌、肾内科抽取559例2型糖尿病患者作为研究对象,采用健康素养量表、服药依从性量表、主观社会隔离量表以及Frail衰弱量表对其进行问卷调查。结果本研究得出2型糖尿病患者的服药依从性良好率为35.78%,Logistic回归分析显示,衰弱、健康素养、主观社会隔离、糖尿病病程是2型糖尿病患者服药依从性的影响因素。结论住院2型糖尿病患者的服药依从性现状不是很乐观,医护人员应重视住院2型糖尿病患者的服药依从性水平,并及时采取措施提高2型糖尿病患者的服药依从性。 展开更多
关键词 2型糖尿病患者 服药依从性 衰弱 主观社会隔离 相关性
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聚甲基丙烯酸对STI CMP中SiO_(2)和Si_(3)N_(4)去除速率选择比的影响
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作者 李相辉 张祥龙 +3 位作者 孟妮 聂申奥 邱宇轩 何彦刚 《半导体技术》 北大核心 2024年第2期131-137,共7页
在浅沟槽隔离(STI)化学机械抛光(CMP)中,需要保证极低的Si_(3)N_(4)去除速率,以及相对较高的SiO_(2)去除速率,并且要达到SiO_(2)与Si_(3)N_(4)的去除速率选择比大于30的要求。在CeO_(2)磨料质量分数为0.25%,抛光液pH=4的前提下,研究了... 在浅沟槽隔离(STI)化学机械抛光(CMP)中,需要保证极低的Si_(3)N_(4)去除速率,以及相对较高的SiO_(2)去除速率,并且要达到SiO_(2)与Si_(3)N_(4)的去除速率选择比大于30的要求。在CeO_(2)磨料质量分数为0.25%,抛光液pH=4的前提下,研究了聚甲基丙烯酸(PMAA)对SiO_(2)与Si_(3)N_(4)去除速率以及二者去除速率选择比的影响,分析了PMAA在影响SiO_(2)与Si_(3)N_(4)去除速率过程中的作用机理。结果表明,PMAA的加入可以降低SiO_(2)与Si_(3)N_(4)的去除速率,当PMAA的质量分数为120×10^(-6)时,SiO_(2)和Si_(3)N_(4)的去除速率分别为185.4 nm/min和3.0 nm/min,去除速率选择比为61。抛光后SiO_(2)与Si_(3)N_(4)晶圆表面有较好的表面粗糙度,分别为0.290 nm和0.233 nm。 展开更多
关键词 浅沟槽隔离(STI) 化学机械抛光(CMP) 二氧化硅(SiO_(2)) 氮化硅(Si_(3)N_(4)) 聚甲基丙烯酸(PMAA) 去除速率选择比
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一株3,5,6-三氯-2-吡啶酚降解菌Delftia sp.DFT的分离鉴定及降解途径研究
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作者 贾楠 岳彩旭 +3 位作者 吕雪茹 王雪婷 丁宁 王圣惠 《聊城大学学报(自然科学版)》 2024年第2期89-100,共12页
微生物降解是消除农药残留物3,5,6-三氯-2-吡啶酚(TCP)的有效方法,但其降解机制并不清楚。为探究TCP完整的代谢途径和降解机制。采用富集分离法从农田土壤中分离了一株TCP降解细菌,并分别通过高效液相色谱和液相色谱-质谱(LC-MS)技术检... 微生物降解是消除农药残留物3,5,6-三氯-2-吡啶酚(TCP)的有效方法,但其降解机制并不清楚。为探究TCP完整的代谢途径和降解机制。采用富集分离法从农田土壤中分离了一株TCP降解细菌,并分别通过高效液相色谱和液相色谱-质谱(LC-MS)技术检测了菌株的降解性能,并鉴定了其代谢产物。该菌株为Delftia sp.DFT菌,它能在48 h内对50 mg/L的TCP降解率达34.28%,同时也能降解3,5-二氯-2-吡啶醇、6-氯-2-吡啶醇和2-羟基吡啶等其他氯代吡啶类化合物。在降解TCP过程中,共鉴定了12种不同的TCP代谢产物。初步推测水解-氧化脱氯途径、还原脱氯途径、反硝化及烷基化途径可能共同参与了菌株DFT对TCP的降解。据文献调研,这是首次在Delftia sp.菌中发现有四种可能的TCP代谢途径的报道,这为纯培养物中的TCP降解机制研究提供了参考信息。 展开更多
关键词 3 5 6-三氯-2-吡啶酚 降解菌 分离鉴定 代尔夫特菌 降解途径
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Genetic Variation of Porcine Circovirus Type 2 Isolate 201105ZJ
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作者 王小敏 何孔旺 +5 位作者 汪伟 周忠涛 杨光远 茅爱华 俞正玉 倪艳秀 《Agricultural Science & Technology》 CAS 2014年第11期1860-1864,1887,共6页
[Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by P... [Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by PCR and IFA. Ful-length genome of the isolated strain was obtained by specific amplification for homology and phylogenetic analysis. [Result] A PCV2 strain was successful y isolated and named 201105ZJ, which could proliferate in PK15 cel lines. Specific fragments could be amplified by specific PCR assay. According to results of IFA assay, specif-ic immunofluorescence was observed; the TCID50 was low (102.67); the ful-length genome sequence of the isolated strain was 1 768 bp, sharing 94.1%-96.8% ho-mology with 13 reference strains; to be specific, the isolated strain exhibited the highest homology of 96.8% with AF055392PCV2a; the isolated strain 201105ZJ and reference strain AF055392 belonged to genotype PCV2a, exhibiting a distant genetic relationship with genotype PCV2c. [Conclusion] Characteristics of genetic variation of PCV2 isolate 201105ZJ provided theoretical basis for vaccine development, investi-gation of PCV2 pathogenesis, and prevention and control of porcine circovirus-as-sociated diseases (PCVAD) in East China. 展开更多
关键词 Porcine circovirus type 2 isolation Identification Genetic variation
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SF_(6)/N_(2)混合气体隔离开关气流场特性仿真研究
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作者 董华军 姚佳岐 +2 位作者 孙鹏 郭沂 戴晓鸣 《大连交通大学学报》 CAS 2023年第1期27-31,共5页
研究SF_(6)/N_(2)混合气体隔离开关的气流场特性对于减少隔离开关的试验次数,完成优化设计及降低研发成本具有重大意义。实验创建了SF_(6)/N_(2)混合气体隔离开关2D轴对称模型,利用ANSYS软件进行网格划分,基于Fluent软件针对开断过程中... 研究SF_(6)/N_(2)混合气体隔离开关的气流场特性对于减少隔离开关的试验次数,完成优化设计及降低研发成本具有重大意义。实验创建了SF_(6)/N_(2)混合气体隔离开关2D轴对称模型,利用ANSYS软件进行网格划分,基于Fluent软件针对开断过程中内部气体的压强、密度及温度场特性进行仿真分析,以开断速度为0.5 m/s的仿真结果总结变化规律,并改变触头开断速度为1.0 m/s和0.3 m/s来监测一点处气流场特性,对比上述三次仿真结果。结果表明:气流场的压强、气体密度与温度呈周期性振荡衰减趋势,直到几乎稳定在初始状态,并且它们的变化成正比。此外对比发现,不同的工作条件对隔离开关气流场的开断特性有一定的影响,可以通过调整工作条件进而实现隔离开关的优化设计和性能提升。 展开更多
关键词 隔离开关 气流场特性 SF_(6)/N_(2)混合气体 仿真研究
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血清Ⅱ型鸡马立克氏病毒的分离鉴定及SW14分离株pp24基因的序列分析 被引量:2
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作者 林雨萌 胡明雪 +10 位作者 刘长军 葛成菲 郭榕容 李凯 崔红玉 高立 祁小乐 王素艳 王笑梅 高玉龙 张艳萍 《中国预防兽医学报》 CAS CSCD 北大核心 2023年第8期864-868,共5页
为了解鸡马立克氏病毒(MDV)在我国鸡群中的流行情况,本研究于2021年从福建省已免疫鸡马立克氏病(MD)疫苗鸡群且发生疑似MD病例的鸡场采集21份疑似发病蛋鸡外周血,分离其淋巴细胞接种鸡胚成纤维细胞(CEF),5 d后收集病毒,盲传1~2代后获得2... 为了解鸡马立克氏病毒(MDV)在我国鸡群中的流行情况,本研究于2021年从福建省已免疫鸡马立克氏病(MD)疫苗鸡群且发生疑似MD病例的鸡场采集21份疑似发病蛋鸡外周血,分离其淋巴细胞接种鸡胚成纤维细胞(CEF),5 d后收集病毒,盲传1~2代后获得21株能够形成典型MDV蚀斑的分离株,依次命名SW1~SW21,采用PCR分别扩增MDV血清Ⅰ型(MDV-1) Meq基因、Ⅱ型(MDV-2) ORF873基因、Ⅲ型(MDV-3) US3基因进行MDV分型鉴定,扩增鸡传染性贫血病毒(CAV) VP3基因、禽网状内皮组织增殖病病毒(REV) LTR基因、禽白血病病毒A亚群(ALV-A)、B亚群(ALV-B)、J亚群(ALV-J)的env基因进行外源病毒检测,结果显示MDV-1均为阴性,MDV-2均为阳性,MDV-3阳性率为38.1%(8/21),未检测到外源病毒基因。在MDV-2分离株中选择SW14株进行pp24基因的PCR扩增,测序后与MDV-2参考株SB-1、301B/1、HPRS24的pp24基因进行基因序列比对分析,结果显示,SW14和SB-1株同源性(96.3%)最高。通过透射电镜观察SW14,可见分离株呈双环型,直径约110 nm,符合MDV病毒粒子形态特征。本研究证实该鸡场中存在MDV-2流行,可能会影响疫苗的免疫效果,但其致病性有待进一步研究。本研究从疑似发病蛋鸡中分离到新的MDV-2株,为我国MDV-2的研究提供重要参考依据,同时为我国MD疫情防控提供有价值的研究材料。 展开更多
关键词 鸡马立克氏病毒 分离鉴定 血清Ⅱ型 血清Ⅲ型 pp24基因序列分析
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猫细小病毒洛阳分离株VP2蛋白原核表达及多克隆抗体制备 被引量:2
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作者 王文婕 茹鹏辉 +5 位作者 郁川 杜付熙 陈松彪 尚珂 张春杰 程相朝 《中国畜牧兽医》 CAS CSCD 北大核心 2023年第4期1511-1521,共11页
【目的】研究旨在对猫细小病毒(Feline panleukopenia virus,FPV)洛阳分离株VP2蛋白进行原核表达和鼠源多克隆抗体制备。【方法】根据已公布的FPV VP 2基因序列(GenBank登录号:EU018143.1)设计1对特异性引物,以洛阳地区7例疑似FPV感染... 【目的】研究旨在对猫细小病毒(Feline panleukopenia virus,FPV)洛阳分离株VP2蛋白进行原核表达和鼠源多克隆抗体制备。【方法】根据已公布的FPV VP 2基因序列(GenBank登录号:EU018143.1)设计1对特异性引物,以洛阳地区7例疑似FPV感染猫粪便为样本提取DNA,对VP 2基因进行PCR鉴定及测序,利用Mega 11.0软件对VP 2基因进行遗传进化分析;应用在线软件预测分离株VP2蛋白结构特征并找出优势抗原表位,克隆VP2优势抗原(sVP2)并连接pET-32a(+)载体,构建pET-32a-sVP2重组质粒,转化大肠杆菌Rosetta(DE3)感受态细胞后进行诱导表达,对重组蛋白表达条件进行优化,并使用SDS-PAGE与Western blotting方法进行鉴定;将pET-32a-sVP2用镍柱亲和层析蛋白纯化后免疫BABL/c小鼠,制备多克隆抗体,采用ELISA法检测抗体效价。【结果】分离得到1株FPV,命名为LY-1。遗传进化分析发现,该毒株属于FPV-G2亚群,与北京株(GenBank登录号:MT270581)亲缘关系最近。生物信息学分析显示,VP2属于稳定膜内蛋白,无信号肽与跨膜区,在N-端具有丰富的B细胞抗原表位(1―800 bp,sVP2)。试验成功构建pET-32a-sVP2重组质粒并表达,SDS-PAGE显示重组蛋白分子质量约50 ku,主要以包涵体形式存在,在30℃、1 mmol/L IPTG诱导6 h蛋白表达量最佳;Western blotting结果表明,重组蛋白能与鼠抗His单克隆抗体发生特异性反应;ELISA结果表明,该重组蛋白抗体效价为1∶128000,能够较好地识别免疫原sVP2和原核表达VP2蛋白并发生特异性反应。【结论】本试验克隆获得FPV sVP2片段,并制备多克隆抗体,为进一步研究VP2在FPV复制和致病过程中的作用及建立诊断FPV方法提供参考。 展开更多
关键词 猫细小病毒(FPV) 洛阳分离株 VP 2基因 原核表达 多克隆抗体
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