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101.
新疆绵羊致病株李斯特杆菌分离与鉴定   总被引:1,自引:0,他引:1  
本研究采用生化反应,溶血试验,致病力试验,PCR方法对分离的新疆5株绵羊致病株李斯特杆菌90SB1,90SB2,90SB5,90SS1,125SL进行了种型的鉴别测定,并用RAPD技术对这5株李斯特杆菌及标准株李斯特杆菌进行分型。试验结果,五株绵羊致病株(野毒株),在生化反应,培养特性,溶血性,致病性及溶血素基因特异性等方面表现高度的一致性,属于同一种LM。RAPD实验表明此5株LM指纹图谱相同,属于同一个型。此5株致病性LM与标准LM对照株(从食品中分离到)指纹图谱差异显著,属于不同型。  相似文献   
102.
对上海5例5~13周龄断奶仔猪多器官衰竭综合征(PMWS)并发猪繁殖与呼吸综合征(PRRS)自然病例进行了病理组织学观察。结果:5例病猪均出现坏死性淋巴结炎、间质性肺炎以及不同程度的坏死性脾炎、间质性肾炎和肝炎。2例病猪出现心肌炎,表现为心肌纤维断裂、溶解和心肌间质中淋巴细胞局灶性浸润。2例病猪出现脑炎,在大脑白质区出现神经胶质细胞结节。  相似文献   
103.
AIM:To evaluate the effects of tetramethylpyrazine (TMP) on calcineurin (CaN) and proliferating cell nuclear antigen (PCNA) gene expression in the proliferation of vascular smooth muscle cells (VSMCs) treated by angiotensin Ⅱ (AngⅡ).METHODS:A cell proliferating model of VSMCs induced by AngⅡ was established.PCNA gene exprersion was observed by immunocytochemical staining and image analysis technique;Calcineurin (CaN) activity was detected by enzyme reaction phosphorus measurement.RESULTS:AngⅡ significantly stimulated the proliferation of VSMCs,cell proliferation activity,CaN activity and the expression levels of PCAN were higher than those in control (P<0.01).While treated with TMP,the CaN activity and PCNA expression were obviously lower than those in AngⅡ group (P<0.01).CONCLUSION:The VSMCs proliferation induced by AngII can be inhibited by tetramethylpyrazine significantly,and the inhibiting mechanism of TMP may be related to inhibiting CaN activity and restraining the expression of PCNA in a dose and time-dependent manner.  相似文献   
104.
AIM:To investigate the modulation of LOX-1 and monocyte-endothelium adhesion by TLR4 activation in human umbilical vein endothelial cells (HUVECs),and explore LOX-1’s role in mediating monocyte-endothelium adhesion,and the effect of atorvastatin.METHODS:TLR4 and LOX-1 mRNA were measured by RT-PCR.The expression percentage of TLR4 and LOX-1 positive cells were detected by flow cytometry.The adhesive percentage between monocytes and HUVECs were determined by counting.RESULTS:Incubation by LPS (1 mg/L) for 24 hours upregulated TLR4,LOX-1 mRNA and protein expression in HUVECs,and increased the percentage of monocyte adhesion to endothelium.Pretreatment of cell with anti-LOX-1 partly abolished the increase of monocyte adhesion to endothelium.Atorvastatin (10 μmol/L) inhibited LPS-mediated effects above.CONCLUSION:TLR4 activation upregulates LOX-1 expression and increases monocyte-endothelium adhesion.LOX-1 partly involves in LPS-induced monocyte-endothelium adhesion,atorvastatin may have protective effects on endothelium by inhibiting TLR4 and TLR4-induced LOX-1 expression.  相似文献   
105.
AIM:To study the effect of basil polysaccharide on the rat model bearing NuTu-19 cells.METHODS:The rat model bearing NuTu-19 cells was treated with basil polysaccharide.The changes of the tumor cell biology and histopathology were observed.Total RNA was isolated from the tumor tissue.Hybridization assay was performed using gene expression microarray.The results were analyzed by photo disposal software-GenePix Pro3.0.RESULTS:Compared with control,the amounts of ascites in the rats treated with basil polysaccharide were decreased (P<0.05) and the scores of abdominal carcinoma metastasis were changed significantly (P<0.01).268 differentially expressed genes were found in the tumor specimen from the rats exposed to basil polysaccharide.CONCLUSION:Basil polysaccharide may be a new anti-tumor drug and it has multi-targets.Gene expression microarray has huge advantage and value in the study of the drug target.  相似文献   
106.
AFLP标记是一种新的DNA分子标记技术。对AFLP标记的基本原理、技术流程和关键技术做了简要介绍,从亲缘关系与遗传多样性分析、遗传图谱的构建、特定性状的连锁标记、品种纯度鉴定与QTL分析等方面概述了AFLP标记在大白菜遗传育种中的应用进展,并对其应用前景进行了展望。  相似文献   
107.
家蝇抗菌肽的分离纯化及生物学活性   总被引:4,自引:0,他引:4  
将诱导家蝇提取的家蝇抗菌肽提取物,经凝胶过滤层析和离子交换层析,得到具有抗菌活性的单一峰,质谱结果显示抗菌肽分离物含有4种小肽,相对分子质量678.3~1017.2。家蝇抗菌肽对革兰氏阴性菌(大肠杆菌、巴氏杆菌)的抗菌活性优于革兰氏阳性菌(金黄葡萄球菌、枯草芽孢杆菌),对耐药性巴氏杆菌有较强的抗菌活性,对大肠杆菌的MIC为4.2~8.4mg/L,对耐药性巴氏杆菌的MIC为3.8~7.8mg/L。扫描电镜观察发现,家蝇抗菌肽通过损伤细胞壁使细胞质外流而达到杀菌的目的。家蝇抗菌肽对家兔、鸡、猪、小鼠、番鸭、鹅和家鸭红细胞无溶血反应和凝集反应。‘  相似文献   
108.
鸡H-FABP基因多态性及其与肌内脂肪含量的相关研究   总被引:10,自引:0,他引:10  
根据GenBank发表的鸡H-FABP基因序列设计引物,以广东省农科院畜牧研究所提供的4个地方优质肉鸡品种,2个培育品种和1个引进的肉鸡品种为试验材料,通过测序和PCR-SSCP的方法进行SNP检测和基因型分析,探讨H-FABP基因多态性与肌内脂肪含量(IMF)之间的关系。结果发现在H-FABP基因260 bp和675 bp处存在T/C和G/A的突变位点,对2个突变位点在研究群体中进行基因型分析,结果产生3种基因型。基因型与IMF的相关分析结果表明:在T260C位点上,所有品种中AA基因型的IMF含量显著(P<0.05)高于BB基因型个体,但对于不同的品种来说,AA和BB基因型只对封开杏花鸡和岭南黄鸡II号的IMF含量有显著影响(P<0.05),而对其他各鸡种均无显著影响(P>0.05);在G675A位点上,所有品种中AA型和AB型肌内脂肪含量差异显著(P<0.05)。  相似文献   
109.
为了探讨鸵鸟对H5亚型禽流感灭活疫苗的免疫原性,做好鸵鸟禽流感的防控工作,采用哈尔滨兽医研究所研制的重组H5N1亚型禽流感疫苗,不同剂量免疫鸵鸟,用HI方法检测母源抗体和免疫抗体,根据母源抗体的衰减和免疫抗体的消长规律确定首免和再免日龄.结果表明,雏鸵鸟母源抗体能维持约3周~8周;8周龄时分组首免,C1组产生的免疫反应优于C2组,抗体峰值能达到7.50 log2,维持时间为9周左右;17周龄时C1组以3.0 mL/羽进行二免,2周后抗体达到7.40log2,3周~7周抗体维持在高峰值,最高达8.80log2,以后逐渐下降,有效抗体水平能维持至接种后25周左右.二免后25周进行三免,以5 mL/羽三免后2周抗体可达到9.80log2,2周~4周抗体维持在最高峰,以后缓慢下降,期间抗体时有起伏,但有效抗体水平约可维持1年时间.三免后45周内抗体水平合格率均在70%以上.根据抗体消长规律,初步推荐了鸵鸟的免疫程序.  相似文献   
110.
AIM: Cinnamyl aldehyde (CA) is one alcohol ingredient derived from Cinnamomum cassia,which is widely used in treating chronic skin wound in Chinese medicine with the curative effect of ‘rescuing YANG’.The purpose of the present study was to investigate the expression of c-Fos,c-Myc proteins at different time points in NIH3T3 treated with CA and explore the possible mechanism of promoting cell proliferation by CA.METHODS: MTT assay was used for observing cell proliferation.Expression of c-Fos and c-Myc proteins in NIH3T3 cells were assessed by immunocytochemistry assay.RESULTS: The cell proliferation was promoted obviously when CA concentration was between 8.8×10-2 μg/L and 8.8×10 μg/L.CA at concentration of 5.5 μg/L significantly induced expression of c-Fos,c-Myc proteins at 2-3 h after the stimulation compared with control group (P<0.01).CONCLUSION: CA increases expression of c-Fos and c-Myc proteins,which may be one of mechanisms for CA to promote NIH3T3 cell proliferation.  相似文献   
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