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排序方式: 共有170条查询结果,搜索用时 15 毫秒
1.
A large, firm, multi-cystic mammary gland mass grew slowly over 4 y in a 12-y-old, female Finn–Shetland cross sheep. A diagnosis of epithelial malignancy was suspected following fine-needle aspiration cytology at 30 mo after initial observation. The sheep was euthanized when the flock was downsized 18 mo later. A field postmortem examination revealed a large mammary mass, but an absence of metastases to internal organs. Imprint cytology of the mammary tissue supported a benign proliferative process. Histologically, mammary tissue was obliterated by cystic, tubular, and papillary adenomatous arrangements of mammary epithelium, with an anaplastic component, consistent with mammary carcinoma arising in an adenoma. IHC showed strong nuclear positivity to the antibody against progesterone receptor and minimal positivity to the antibody against estrogen receptor alpha expression. Intrinsic subtyping for basal or luminal epithelial origin was attempted through adaptation of companion animal IHC classification panels; high- and low-molecular-weight cytokeratins (CK5, CK8, CK18) failed to stain, but p63 expression for basal epithelium was positive.  相似文献   
2.
I—ELISA特异诊断棘球蚴(包虫)病的研究   总被引:1,自引:1,他引:0  
采用亲和层析技术纯化的兔抗棘球蚴抗体,建立了酶联免疫吸附抑制试验(I—ELISA)。取代反应和阻断反应均无非特异反应;检测健康对照血清126份(人36,猪90),均为阴性;与猪囊尾蚴病血清136份(人46,猪90)、细颈囊尾蚴病血清38份(羊22、猪16)无交叉反应;对棘球蚴病血清183份(人61、羊71、猪51)进行检测,其阳性符合率分别为88.5%(54/61)、98.6%(70/71)、96.1%(49/51)。  相似文献   
3.
用分子生物学方法鉴别检测动物源性饲料中的牛羊源性成分   总被引:10,自引:0,他引:10  
为了防止海绵状脑病疫区和痒病疫区反刍动物源性饲料进入我国 ,非常有必要对贸易往来中的肉骨粉品种来源进行鉴定检测。我们采用分子生物学方法从动物源性饲料中鉴别检测牛、羊特异性线粒体DNA的片段 ,并用限制性内切酶SspⅠ对PCR产物进行酶切鉴定及DNA序列测定。该方法的灵敏度可达 0 .12 5 % ,具有灵敏度高、快速和特异性强的优点。  相似文献   
4.
600 g 冰冻羊垂体经过酸性溶液提取、硫酸铵的分级分离和 DEAE-纤维素柱层析得纯品(1),其得率为0.08g/kg,最后将部分纯品(1)过 Sephadex G-100分子筛,得到高纯的羊生长激素[纯品(2)]。提取的羊生长激素具有相当高的理化均一性,纯品(2):聚丙烯酰胺凝胶电泳呈现一条主带和二条酸性小带;聚丙烯酰胺等电聚焦电泳呈现二条带,其等电点分别为 pH7.35和 pH7.40,SDS—电泳呈现二条很难分开的带,其平均分子量为20 100道尔顿;用DNS-CI 法测得的 N-末端氨基酸是2个,丙氨酸和苯氨酸。纯品(1)理化均一性稍差:SDS—电泳较纯品(2)多出两条分子量低的带;等电聚焦电泳多出六条酸性小带。除此之外,其他理化性质同纯品(2)。用大白鼠胫骨实验测定生物活性,测得纯品(1)可使垂体大白鼠胫骨软骨盘的宽度相对增加79%。未对纯品(2)进行生物活性测定。用羊催乳素放射免疫药盒测定,纯品(1)和纯品(2)与羊催乳素均无交叉反应。  相似文献   
5.
A survey on ovine dairy farms directly transforming own‐produced milk, in the Italian Marche region, was carried out to assess flock and milking practices that may influence milk hygienic‐sanitary conditions. A census survey established that 24 dairy farms were located in this region. Bulk milk samples were collected throughout the milking period in each dairy farm in 2013. Analyzed variables were: (i) chemical parameters such as fat, protein and lactose content, dry matter and pH; and (ii) total bacterial (TBC) and somatic cell counts (SCC). Chemical parameter values were in agreement with published data while, geometric mean (GM) log10 SCC was 5.91 and TBC GM was 57 978 colony forming units/mL, in compliance with Eropean Union criteria. A positive correlation was found between SCC and TBC when GMs of all farm data were considered (Spearman's rho = 0.7925; P = 0.0001). Statistical analysis did not show significant correlation between SCC or TBC GM and dairy farm principal characteristics. Although SCC levels detected in the present study should suggest the need to implement mastitis control programs, Marche's dairy sheep flocks revealed a good hygienic condition level. This is an important aspect in implementing safety for end users of the final product.  相似文献   
6.
OBJECTIVE: To determine the sensitivity and specificity of an absorbed ELISA and an AGID test for the detection of clinical and subclinical paratuberculosis in sheep. DESIGN: By testing a panel of sera from 1257 Australian Merino and crossbred sheep greater than 1 year of age, of which 1137 sheep were not infected with Mycobacterium avium subsp paratuberculosis and 120 sheep had paratuberculosis. PROCEDURE: Sera were collected from 457 sheep in Victoria and 800 sheep in Western Australia. Presence of M a paratuberculosis infection in Victorian sheep was determined by histological examination of intestinal tissues, whereas sheep from Western Australia were presumed to be free of Johne's disease. The ability of an absorbed ELISA to discriminate between infected and uninfected sheep was described by test sensitivity and specificity, the distribution of ELISA OD, and the area under a receiver operating characteristic curve. RESULTS: The absorbed ELISA had a specificity of 98.2 to 99.5% (CI) and a sensitivity of 35 to 54% (CI). In sheep from infected flocks in Victoria, the AGID test had a specificity of 99 to 100% (CI) and a sensitivity of 38 to 56% (CI). The sensitivity of serological tests was higher in sheep with a body condition representative of the lower quintile of their flock of origin. CONCLUSION: The AGID test and absorbed ELISA are useful tests for the detection of ovine paratuberculosis. Although the tests had a similar accuracy, they detected different subpopulations of infected sheep with only moderate overlap. The AGID test had a higher specificity than the absorbed ELISA.  相似文献   
7.
A fibroadenoma was diagnosed in the left udder of a 3-month-old female Chios lamb. No recurrence was observed after surgery. Grossly, the tumor had a whitish-gray lobular appearance, and the lobules were interlaced with thin septa. Microscopically, the tumor was composed of proliferating fibroepithelial tissue, including differentiated ducts lined by whorls and interlacing bundles of abundant loose fibrovascular stroma. Immunohistochemistry revealed the ductal epithelium to be positive for pancytokeratin (AE1/AE3) and loose fibrovascular stroma was positive for vimentin and basal cells covering the ductal epithelium of alpha-smooth-muscle actin. Immunostaining for the estrogen and progesterone receptors was negative. A diagnosis of mammary fibroadenoma was made based on the histological and immunohistochemical findings.  相似文献   
8.
不同培养液及血清浓度对绵羊孤雌生殖胚胎发育的影响   总被引:1,自引:0,他引:1  
体外成熟的绵羊卵母细胞,经5 μmol/L A23187 5 min和2 mmol/L 6-DMAP 4 h激活后,分别在SOFaa、M-199两种培养液中进行培养,试验比较了SOFaa、M-199液分别添加BSA和不同浓度(10%、20%)胎牛血清对绵羊孤雌生殖胚体外发育的影响。M-199+FCS组的卵裂率显著低于SOFaa+BSA和SOFaa+FCS组(P<0.05),SOFaa+BSA组的囊胚率显著低于M-199+BSA、SOFaa+FCS、M-199+FCS三组(P<0.05);SOFaa+10% FCS与SOFaa+20% FCS组的卵裂率及囊胚率均无显著差异,M-199+10% FCS和M-199+20% FCS组的卵裂率及囊胚率间均无显著差异。结果表明:SOFaa比M-199更适合绵羊孤雌生殖胚体外发育,此外添加10%的FCS即可达到较好的培养效果。  相似文献   
9.
本试验主要从采集方法和性周期阶段2方面对绵羊卵母细胞体外成熟的影响进行了探讨。结果表明:不同采卵方法的采卵效果存在差异,卵裂率切割法显著高于抽吸法(27.9%,49.5%;P<0.05);A、B级卵母细胞成熟率极显著高于C级(75.3%,64.4%,29.1%,P<0.01),卵裂率A、B级均显著高于C级(42.5%,35.8%,16.0%,P<0.05);从卵泡期和黄体期卵巢采集到的卵母细胞的体外成熟率和卵裂率分别为66.7%、62.9%;38.2%、34.4%,没有显著差异 (P>0.05)。  相似文献   
10.
对从羊脂中制取肥皂的工艺条件进行了研究,经过净化、皂化、盐析等工艺制取出具有广阔市场前景和经济效益的化工产品肥皂。  相似文献   
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