共查询到20条相似文献，搜索用时 31 毫秒
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为了解猪繁殖与呼吸综合征病毒(PRRSV) Nsp7的免疫原性,本研究将PRRSV Nsp7进行了原核表达.SDS-PAGE和western blot试验表明,Nsp7在大肠杆菌中获得大量表达,并且其具有较好的反应活性.采用Nsp7免疫小鼠制备多克隆抗体,并进行间接ELISA检测,表明多克隆抗体效价达到1∶32000以上;间接免疫荧光试验表明,多克隆抗体能够特异性识别PRRSV的Nsp7,显示出Nsp7具有较好的免疫原性.本研究获得了高纯度可溶性的PRRSV Nsp7,并进一步制备多克隆抗体,为研究Nsp7蛋白的免疫学特性提供实验依据. 相似文献
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CHRISTINE GIBBS 《The Journal of small animal practice》1976,17(8):551-554
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Gonzales JL Elbers AR Bouma A Koch G de Wit JJ Stegeman JA 《Veterinary microbiology》2012,155(2-4):207-213
Low pathogenic avian influenza virus (LPAIv) infections of H5 and H7 subtypes in poultry are notifiable to the OIE, hence surveillance programmes are implemented. The rate at which LPAIv strains spread within a flock determines the prevalence of infected birds and the time it takes to reach that prevalence and, consequently, optimal sample size and sampling frequency. The aim of this study was to investigate the transmission characteristics of an H7N7 and an H5N7 LPAIv in layer chickens. Two transmission experiments were performed, which consisted of 30 (first experiment) and 20 (second experiment) pairs of conventional layers, respectively. At the start of the experiments, one chicken per pair was inoculated with LPAIv and the other chicken was contact-exposed. Occurrence of infection was monitored by regularly collecting tracheal and cloacal swab samples, which were examined for the presence of virus RNA by RT-PCR. The results of the test were used to estimate the transmission rate parameter (β), the infectious period (T) and the basic reproduction ratio (R(0)). In addition, egg production and virus shedding patterns were quantified. For the H7N7 virus, the β, T and R(0) estimates were 0.10 (95% confidence interval (CI): 0.04-0.18) day(-1), 7.1 (95% CI: 6.5-7.8) days and 0.7 (95% CI: 0.0-1.7), respectively. With the H5N7 virus, only a few inoculated chickens (5 out of 20) became infected and no transmission was observed. This study shows that transmission characteristics of LPAIv strains may vary considerably, which has to be taken into account when designing surveillance programmes. 相似文献
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《Australian veterinary journal》1974,50(11):526-527
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Ishino H Hara Y Takekoshi S Teshima T Teramoto A Osamura RY Tagawa M 《Domestic animal endocrinology》2011,41(4):207-213
Pituitary-dependent hyperadrenocorticism (PDH) caused by pituitary corticotroph adenoma is a common endocrine disorder in dogs. The ratio between pituitary height and the area of the brain (P/B) has been used to evaluate the pituitary size. A P/B ratio > 0.31 indicates an enlarged pituitary, whereas a P/B ratio ≤ 0.31 indicates a nonenlarged pituitary. The aim of this study was to investigate the expression of proliferation markers Ki-67 and minichromosome maintenance-7 (MCM7) in canine corticotroph adenomas in enlarged and in nonenlarged pituitaries and to evaluate their relation with the size of canine pituitary corticotroph adenomas. Ki-67 and MCM7 expression in ACTH-positive tumor cells was determined by dual-labeling immunohistochemistry in resected corticotroph adenomas from 15 dogs with PDH. The mean ± SD Ki-67 labeling index (LI) was 0.55% ± 0.59% in corticotroph adenomas with nonenlarged pituitaries and 1.6% ± 0.6% in adenomas with enlarged pituitaries. The MCM7 LI in corticotroph adenomas with nonenlarged pituitaries and in adenomas with enlarged pituitaries was 2.9% ± 2.2% and 10.9% ± 3.7%, respectively. The Ki-67 LI and MCM7 LI were significantly greater in the adenomas with enlarged pituitaries than in the adenomas with nonenlarged pituitaries (P < 0.01 and P < 0.01, respectively). The MCM7 LI was significantly greater than the Ki-67 LI in adenomas (P < 0.01). The Ki-67 LI was positively correlated with the MCM7 LI (r = 0.820, P < 0.01), and the P/B ratio was positively correlated with the Ki-67 LI (r = 0.560, P = 0.03) and the MCM7 LI (r = 0.854, P < 0.01). In conclusion, canine corticotroph adenomas in enlarged pituitaries show greater proliferation potential than do adenomas in nonenlarged pituitaries. MCM7 expression was significantly greater than Ki-67 expression in canine pituitary corticotroph adenomas. Thus, MCM7 may be superior to Ki-67 as a proliferation marker in pituitary tumors. 相似文献
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为实现家兔BMP7基因原核表达及探索适宜的表达条件,采用PCR技术从pMD18-T-BMP7重组质粒中扩增获得BMP7基因成熟肽片段(mBMP7),构建原核表达工程菌pET32a-mBMP7/BL21(DE3)和pET32a-mBMP7/BL21(DE3)pLysS,并比较温度、IPTG浓度、诱导时间等因素对目的蛋白表达的影响。结果表明,mBMP7原核表达载体构建正确;工程菌pET32a-mBMP7/BL21(DE3)和pET32a-mBMP7/BL21(DE3)pLysS经IPTG诱导均可表达含有家兔BMP7成熟肽的34KDa的融合蛋白,表达产物约占菌体总蛋白的30%。在37℃、0.75 mM IPTG以及诱导150 min时,能取得较高的目的蛋白表达量;在20℃低温条件下,IPTG浓度和诱导表达时间应分别以0.20 mM和7 h为宜;另外,目的蛋白表达对工程菌生长无明显的不利影响。因此,成功地构建了家兔BMP7基因工程菌,并确定了适宜的表达条件,为进一步研究该蛋白的结构和功能奠定基础。 相似文献
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Bonfanti U Comazzi S Paltrinieri S Bertazzolo W 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(4):234-239
BACKGROUND: Hereditary canine stomatocytosis has been described in purebred Alaskan Malamutes, Drentse Patrijshonds, and Miniature Schnauzers. In humans, hereditary stomatocytosis is a heterogeneous group of congenital disorders characterized by the presence of stomatocytes in blood, increased osmotic fragility, and frequently, hemolytic anemia. OBJECTIVE: Our objective was to describe hematologic findings and RBC characteristics in 7 closely related Standard Schnauzers with stomatocytosis. METHODS: The following parameters were measured using an automated analyzer: HCT, RBC, hemoglobin (Hb) concentration, MCV, MCH, MCHC, red cell distribution width (RDW), WBC, platelet count, mean platelet volume (MPV), thrombocrit (PCT), and platelet distribution width (PDW). Differential leukocyte count, platelet estimate, reticulocyte count, and the percentage of stomatocytes in blood films were microscopically evaluated. An osmotic fragility test of RBCs and measurement of intracellular Na+, K+, and 2,3-diphosphoglycerate (2,3-DPG) concentrations were also performed. RESULTS: The affected dogs had macrocytosis (80.0 +/- 4.2 fL, reference interval 60-76 fL), decreased MCHC (29.3 +/- 0.8 g/dL, reference interval 32-39 g/dL), slightly increased RDW (17.3 +/- 0.4%, reference interval 12-16%), and an increased reticulocyte count (1.55 +/- 0.77%, reference interval <1%). The percentage of stomatocytes in blood films varied from 0.6 to 18.9% of all RBCs. Erythrocyte osmotic fragility and intracellular Na+ (138.1 +/- 3.2 mmol/L; controls 99 +/- 6.1 mmol/L), K+ (8.1 +/- 0.8 mmol/L; controls 6.1 +/- 0.5 mmol/L), and 2,3-DPG (21.9 +/- 2.0 micromol/g Hb; controls: 14.6 +/- 3.3 micromol/g Hb) concentrations were increased in dogs with stomatocytosis. CONCLUSIONS: Hematologic findings and the metabolic defects in RBCs in these Standard Schnauzers were consistent with a diagnosis of stomatocytosis. Parentage analysis suggests that stomatocytosis in Standard Schnauzers may have a hereditary component. 相似文献
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目前,几乎所有饲料原料成本都在大幅度增加.因此,许多饲料和猪肉生产商正在审慎地思考如何降低猪肉生产的饲料成本.不同猪场可以根据其所在区域的市场及生产体系情况,选择适合自己的措施或策略. 相似文献
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为进一步研究胆固醇7α-羟化酶(CYP7A1)在胆汁酸合成和胆固醇代谢过程中的调节机制,采用RT-PCR和RACE方法从鹅(Anser anser)肝组织克隆CYP7A1基因全长cDNA序列,亚克隆其CDS区并构建原核表达载体pET-28a-cyp7α1.重组质粒在大肠杆菌BL21(DE3)菌株中经IPTG诱导表达.经His-Bind纯化试剂盒纯化的His-CYP7A1免疫Bal b/c小鼠,制备小鼠抗鹅CYP7A1多克隆抗体,Western blotting验证His-CYP7A1免疫原性和抗体的特异性.序列分析结果表明,该蛋白与鸡、大鼠、人、短尾猊、小鼠的CYP7A1蛋白氨基酸序列同源性分别为93 ％、66％、67％、68％、66％.SDS-PAGE分析结果表明,重组蛋白His-CYP7A1得到正确高效表达,该His0CYP7A1分子质量约为59 ku,经纯化获得高纯度重组His-CYP7A1蛋白.制备了小鼠抗鹅CYP7A1多克隆抗体,效价达1∶104.Western blotting检测表明,该蛋白能够被小鼠抗His抗体和小鼠抗CYP7A1抗体所识别,小鼠抗CYP7A1多克隆抗体具有较好的特异性.试验结果为进一步研究CYP7A1基因结构和CYP7A1在鹅肝脏脂类代谢中的作用提供了基础和技术手段. 相似文献