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91.
对鸽源冠状病毒PSH株纤突蛋白基因进行了RT—PCR扩增、克隆和测序。结果表明,PSH株S基因由3504个核苷酸组成,编码1条由1167个氨基酸残基组成的多肽。S基因编码产物裂解后形成的S1和S2亚单位分别由541和626个氨基酸残基组成。PSH株S蛋白切割识别位点为精氨酸-精氨酸-苯丙氨酸-精氨酸-精氨酸(RRFRR),与多数鸡传染性支气管炎病毒(IBV)切割识别位点相似(RRF/SRR)。与GenBank中其他冠状病毒毒株S基因的推导氨基酸序列相比较,PSH株与IBV参考毒株的同源性为79.3%~99.6%,而与其他冠状病毒包括火鸡蓝冠病病毒和SARS病毒的同源性均小于37.8%。表明,鸽源冠状病毒PSH株属于第3抗原群冠状病毒,且与IBV亲缘关系较近。  相似文献   
92.
In order to understand the infection of Staphylococcus disease in healthy Tibetan pigs in Linzhi city,Tibet.232 samples were collected from the slaughterhouse in Bahe town,Gongbujiangda county,Linzhi city,Tibet,the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,and the slaughterhouse in Bayi district,Linzhi city.These samples were isolated,cultured and identified,and one isolated strain was systematically studied for biological characteristics.Epidemiological survey results showed that 73 of 232 samples were positive for Staphylococcus,the positive rate was 31.47%,16 positive samples were detected in the slaughterhouse of Bahe town,Gongbujiangda county,Linzhi,Tibet,with a detection rate of 23.89%(16/67),43 positive samples were detected in the pastures of the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,with a detection rate of 34.40% (43/125),14 positive samples were detected in the slanghterhouse in Bayi district,Linzhi city,with a detection rate of 35.00% (14/40).Through PCR identification,gene sequencing and biochemical identification,5 strains of Staphylococcus chromogenes were isolated,and one of them (Sa LZ1) was studied systematically.The biological characteristics of the isolated strains showed that the Sa LZ1 strain formed round white convex colonies on the agar medium,with regular edges,smooth surfaces,and opaque white colonies.The isolates were Gram-positive cocci bacteria.PCR sequencing results showed that the isolate had the highest homology with Staphylococcus chromogenes (GenBank accession No.:MG576253.1),positive for serum inulin,manicol,glucose,saccharose,lactose,negative for arabinose,sodium hippurate,raffinose,xylose,urea,etc,consistent with the biochemical characteristics of Staphylococcus chromogenes.The logarithmic growth period of isolated bacteria was 5 to 10 h.The pathogenicity test of mice showed that the mortality rate of mice reached 100% when the concentration of Sa LZ1 strain reached 3.5×109 CFU/mL.And the results of pathological section showed that Sa LZ1 strain could cause the visceral tissue of mice to develop pathological changes.The above results provided a theoretical basis for the prevention and control of Staphylococcus suis in Linzhi,Tibet.  相似文献   
93.
药食观赏兼用特菜菊花脑无公害栽培技术   总被引:2,自引:0,他引:2  
菊花脑属菊科菊属多年生宿根性草本植物,在江苏多为田边地头野生,近年来有小面积零星栽培,10~11月开花,人们常在4~8月用手掐取其嫩头作为蔬菜食用,具有清热解毒、凉血降压之功效,是一种栽培简易的具有开发价值的营养保健型蔬菜,兼有药用、食用和观赏三重价值.  相似文献   
94.
AIM:To investigate the effect of Sini decoction (SND) on vascular stenosis and the expression of transfoming growth factor-β1 (TGF-β1) in iliac artery balloon injured rabbits. METHODS:24 male New Zealand albino rabbits were divided into three groups:control group, model group and SND treatment group. The iliac arteries were injured by balloon in model and SND groups. Four weeks later, serum TGF-β1 level was assayed by ELISA. Endothelial hyperplasia, TGF-β1 protein and mRNA expression were observed in injured iliac artery. RESULTS:Light microscope showed that the vascular lumina were narrower, intima was thicker in model group control and SND treatment group. The serum TGF-β1 level was lower in control than model group and SND treatment group, and the serum TGF-β1 level in SND treatment group was lower than that in model group. Immunohistochemistry and RT-PCR results showed that TGF-β1 protein and mRNA expression was lower in rabbit iliac artery of control group than that in model group and SND treatment group, and the expression of TGF-β1 protein and mRNA decreased significantly in SND treatment group compared with model group. CONCLUSION:SND could lessen intimal hyperplasia and vascular stenosis in balloon injured iliac artery, which might be related to decrease in TGF-β1 protein and gene expression in iliac artery.   相似文献   
95.
将人溶菌酶(human lysozyme,hLYZ)cDNA插入由pcDNA3改造而成的pcDNAK表达载体。用获得的重组载体pcDNAKLYZ转染COS-1细胞,经免疫荧光试验证明能进行正确表达。将重组载体注射于哺乳母鼠,取其乳汁进行溶菌酶活性测定,结果显示,分泌在乳汁中的重组hLYZ高达139mg/L。根据乳汁体细胞检测结果,选择健康奶牛和乳腺炎阳性奶牛,分别在干奶时和产犊前2周2次注射重组质粒pcDNAKLYZ,注射途径为乳腺基部穿刺,注射剂量为300μg/乳区,于产犊后1个月采集奶样进行体细胞检测,结果显示,对前一泌乳期发生的奶牛乳腺炎的治愈率为91.5%,对下一泌乳期奶牛孔腺炎的预防有效率王少为96.97%。由此认为。构建的表达hLYZ基因的重组表达质粒,可以替代抗菌素类油乳剂用于干乳期乳腺炎的防治。  相似文献   
96.
作者论述了鸡传染性喉气管炎的病原及培养特性、发病机制、诊断方法及其防制,并对传染性喉气管炎的控制和根除进行了展望。  相似文献   
97.
AIM:To study the effect of VEGF on extracellular H2O2 production in HUVECs and the role of H2O2 in the VEGF-induced proliferation. METHODS:HUVECs was stimulated with 500 μg/L VEGF. Products of extracellular H2O2 was detected by H2DCFDA staining. MTT method was used to value the influences of 3×106 U/L catalase and 5-20 mmol/L H2O2 to VEGF function. RESULTS:After treatment for 15 min with VEGF, HUVECs appeared fluorescence, and continued to become stronger, peaked at 45 min then decreased. HUVECs, which was treated simultaneity with VEGF and 3×106 U/L catalase, only appeared very faint fluorescence. The proliferation of HUVECs by VEGF was restrained when treated with 3×106 U/L catalase. The extrinsic H2O2 at concentration of 5-10 mmol/L promoted the proliferation of HUVECs but inhibited the proliferation effect of VEGF on HUVECs (P<0.01). CONCLUSION:These findings indicate that VEGF induces HUVECs to produce extracellular H2O2 and plays role in proliferation, but extrinsic H2O2 restrains VEGF function.  相似文献   
98.
AIM: To investigate the activation of nuclear factor κB (NF-κB) induced by lipopolysaccharides (LPS) in rat alveolar macrophages (AMs) and its regulatory role in tumor necrosis factor (TNF-α) secretion. METHODS: The dynamic activity changes of NF-κB induced by LPS were determined with electrophoretic mobility shift assay (EMSA). Antisense oligonucleotides of NF-κB subunit (p65) were transfected into AMs prior to LPS stimulation. The effect of antisense oligonucleotide transfection on expressions of p65 and TNF-α in supernatant were measured with Western blotting and enzyme linked immunosorbent assay (ELISA), respectively.RESULTS: NF-κB activity increased markedly and reached its peak level at 4 h after LPS stimulation. After transfected with antisense oligonucleotides of NF-κB subunit (p65), expression of p65 and TNF-α in supernatant decreased markedly.CONCLUSION: NF-κB activity has a positive effect on regulating secretion of TNF-α in AMs induced by LPS.  相似文献   
99.
基于微孢子虫分类学地位的争议,通过克隆家蚕微孢子虫(Nosema bombycis)的α-Tubulin基因,利用BioEditor将核苷酸序列翻译成氨基酸序列,并从NCBI中收集不同物种的α-Tubulin基因,用CLUSTALX(1.81)、Mega2以及在线生物信息学软件CLUSTALW(1.83)分析序列并构建系统发育树。结果显示:家蚕微孢子虫及其它微孢子虫与真菌聚为一类,且微孢子虫以一个独立群与接合菌(zygomycetes)的噬虫霉属(Entomophaga)、耳霉属(Conidiobolus)关系最近,与子囊菌(ascomycetes)、担子菌(basidiomycetes)、壶菌(chytrids)及其它接合菌互为姐妹群。  相似文献   
100.
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