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21.
棕色脂肪组织通过大量表达解偶联蛋白-1(UCP-1)以加强线粒体呼吸作用的解偶联,使能量以热量形式散失,从而抵御肥胖和相关疾病.研究发现,PRDM16是调节棕色脂肪细胞形成的关键转录因子,是控制棕色和白色脂肪细胞特异基因表达程序的分子开关,其机制是C末端结合蛋白和过氧化物酶体增殖剂活性受体γ辅助激活子1 (PPARγ-coactivator-1α and β,PGC-1α/β) 竞争性结合PRDM16,分别形成PRDM16/CtBPs和PRDM16/PGC-1s转录复合物,前者可激活棕色脂肪特异基因的表达,后者则抑制白色脂肪特异基因的表达.论文通过对PRDM16的结构、功能及其作用机制的介绍,有助于研究者了解棕色脂肪组织发育的调控系统,为肥胖和相关疾病的治疗提供新思路.  相似文献   
22.
The demography of bovine infections caused by Mycobacterium avium subspecies paratuberculosis (MAP) in Ireland is poorly defined. The objective of this study was to describe the demographics of cattle positive to MAP on faecal culture, based on submissions to the Cork Regional Veterinary Laboratory (Cork RVL) from 1994 to 2006. The study focused on all available faecal samples from adult cattle with non-responsive chronic diarrhoea that were submitted by private veterinary practitioners to Cork RVL for MAP culture. For each MAP-positive by faecal culture animal, data were collated from Cork RVL and Cattle Movement Monitoring Scheme (CMMS) records. Johne's disease (JD) was confirmed in 110 animals from 86 herds by the Cork RVL between 1994 and 2006, with a rate of positive cases between 15% and 18% over last four years of the study. Two breeds (Holstein/Friesian or Limousin) made up 78% of submissions. Movements were assessed for the 57 study animals with available movement information, 90% died within one year of the test and 26% tested positive in the herd they were born into. The study provides preliminary information about movement trends and demographics of animals with MAP positive submissions. Although the study area is restricted, it includes the most intensive (and economically-important) dairy region in Ireland. The demographics of JD infection from the study area are in agreement with international reports. Further work is required to determine demographic trends, incidence and prevalence of JD throughout Ireland. It is hoped this work may contribute to the development of a surveillance strategy for MAP by regional veterinary laboratories.  相似文献   
23.
Murrah buffaloes, best breed for milk production are native of Haryana state. They contributes significantly to the farmer’s income, livelihood and food (milk and meat) security, in the semi-tropical regions of North India. Johne’s disease though endemic in the domestic livestock of the country, but reports are not available in the buffaloes suffering from morbidity due to progressive weakness and diarrhoea. We estimated the status of JD in diarrhoeic buffaloes and cattle reporting at Veterinary Clinical Complex of Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India, using conventional, serological and PCR assays.141 buffaloes suffering from chronic diarrhoea were screened to estimate sero-prevalence of MAP and 50.0 % young and 53.52 % adult animals were positive. Of 14 cattle screened, none of the young and 66.6 % adult cows were positive. In buffaloes, 66.1 and 6.77 %, fecal samples were positive in microscopy and IS900 PCR, respectively. Sero-prevalence of JD was very high in diarrhoeic buffaloes and cattle from Haryana state of India.Buffaloes positive for Mycobacterium avium subspecies paratuberculosis (MAP) infection had reduced total leukocyte count and lymphocytes.  相似文献   
24.
为探究热加工方式对牛乳过敏原αs1-酪蛋白构象和抗原性的影响,利用间接竞争酶联免疫吸附测定方法、 免疫印迹方法分析不同加热条件下αs1-酪蛋白免疫原性的变化,进而通过8-苯胺-1-萘磺酸荧光探针和圆二色谱分 析其二级结构变化,初步揭示热处理调控过敏原αs1-酪蛋白抗原性的机制。结果表明:在80 ℃、60 min,90 ℃、 10 min,90 ℃、60 min条件下热处理后,αs1-酪蛋白中α-螺旋结构含量显著低于未加热αs1-酪蛋白,在70 ℃、 20 min,80 ℃、20 min,90 ℃、20 min条件下热处理后,αs1-酪蛋白中无规卷曲含量显著增加,70~100 ℃加热 20 min条件下表面荧光强度最强,其他温度-时间条件下二级结构含量变化不显著;αs1-酪蛋白构象的变化导致αs1-酪 蛋白的抗原性显著降低,间接竞争酶联免疫吸附测定显示,在70~100 ℃加热20 min条件下,αs1-酪蛋白的抗原残留 量均较高,而免疫印迹方法显示不同温度-时间条件下αs1-酪蛋白仍具有免疫反应特性,建议进一步通过动物实验揭 示热处理调控αs1-酪蛋白抗原性的机制。  相似文献   
25.
酵母硒是饲料中优质的有机硒源,较无机硒具有更高的吸收率与生物安全性,可提高猪的生长、成活率和繁殖性能,而且可提高肉品质和营养价值。作者综述了酵母硒在猪日粮中的应用研究进展。  相似文献   
26.
Erlichia canis, a rickettsial pathogen which infects monocytes, induces generalized lymphocyte activation. Activated T lymphocytes differentiate into effector cells capable of destroying infected and uninfected monocytes and platelets. Activated B lymphocytes differentiate into plasma cells associated with plasmocytosis, hypergammaglobulinemia with high levels of specific antibody and a platelet migration inhibition factor. These effector mechanisms, aimed at parasite destruction, contribute to the pathogenesis of acute tropical canine pancytopenia and do not completely eliminate the etiologic agent. A carrier state of ‘infection-immunity’ exists between the immunocompetent host and virulent parasite. E. canis has evolved mechanisms of ‘tolerant-symbiosis’ with hostile macrophages and other effector cells in the immune host.  相似文献   
27.
28.
One hundred and twenty stranding events of Stejneger’s beaked whales were reported in Japan between 1999 and 2011. The purpose of this study is to introduce pathological data and to discuss probable causes of death for 44 Stejneger’s beaked whales among them. The significant pathological findings were the pulmonary edema, parasitic granulomatous nephritis, emaciation, amyloidosis, suppurative bronchopneumonia and so on. The probable causes of death were categorized as noninfectious in 43 of the cases, which included drowning, starvation and secondary amyloidosis. One individual was diagnosed with septicemia, which was the only example of an infectious disease. Because we could not always perform advanced analyses, such as microbiology tests, biotoxin examinations or contaminant analyses, the finality of our findings may be impaired. However, the present study has broad implications on the causes of death of Stejneger’s beaked whales of the seas around Japan, which are valuable for the future studies and for the detection of emerging diseases.  相似文献   
29.
解读2010年版《中华人民共和国兽药典》一部收载兽药标准的增修订内容和特点,详细描述了兽药典一部收载凡例和兽用化学药品、抗生素等兽药标准的增修订情况。对于读者理解、领会和执行2010年版《中华人民共和国兽药典》一部标准,将起到较好的帮助作用。  相似文献   
30.
The aim of this study was to evaluate the peak in luteinizing hormone (LH) and the pregnancy rate of sheep (Texel × Santa Inês) in the tropics using short‐ (6 days) and long‐term (12 days) progesterone protocols followed by artificial insemination (AI) both in and out of the breeding season. Experiment 1 was conducted within (IN) the breeding season (autumn, n = 36), and experiment 2 was conducted outside (OUT) of the breeding season (spring, n = 43). In each experiment, the sheep were divided into two groups (6 or 12 days) according to the duration of treatment with a single‐use progesterone release vaginal device (CIDR®, Pfizer, São Paulo, SP, Brazil), and blood samples were collected from 10 animals per group every 4 hr to measure the LH and progesterone concentrations. In the spring, the characteristics of the LH peak did not differ between groups; but in the autumn, there were differences between groups at the beginning (G‐6 IN: 36.44 ± 5.46 hr; G‐12 IN: 26.57 ± 4.99 hr) and end of the LH peak (G‐6 IN: 46.22 ± 7.51 hr; G‐12 IN: 34.86 ± 8.86 hr). The results showed alterations in the LH peak during the breeding season only in the sheep undergoing the short‐term protocol.  相似文献   
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