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1.
抑制素免疫对羊生殖的影响   总被引:4,自引:0,他引:4  
抑制素是一种主要由动物性腺(睾丸的支持细胞和卵巢的颗粒细胞)分泌的一种异二聚体糖蛋白激素,由两个二硫键连接两个不同的亚单位(α和β)构成。抑制素对垂体FSH的分泌和/或合成具有选择性地抑制作用。抑制素免疫中和技术能特异性地刺激FSH分泌,进而促进配子生成,提高动物繁殖力。西方把抑制素免疫对羊排卵率、产羔数、初情期、超数排卵和公羊繁殖性能的影响作一综述。  相似文献   

2.
垂体是动物体内重要的内分泌器官,其分泌的各类激素在动物生命过程中发挥关键作用。miRNA是一类广泛存在的非编码小分子RNA,可通过作用于靶基因进而调控机体功能,几乎参与动物体内所有的生物学过程。如今越来越多的研究表明miRNA参与调控垂体发育及垂体激素的合成和分泌。本文主要就miRNA在垂体激素合成和分泌上的调控作用及其靶基因展开综述,为深入研究miRNA在动物垂体上的功能以及改善家畜生长、繁殖和泌乳性能提供参考。  相似文献   

3.
抑制素(Inh ib in,IB)是一种由雌性卵泡颗粒细胞和雄性睾丸支持细胞分泌的糖蛋白激素,由α和β亚基组成的二聚体,其主要生理作用是特异性地调控垂体FSH(促卵泡素)的分泌。自1932年Macullagh提出这个概念以来,动物抑制素的研究日益受到人们的重视。目前对哺乳动物抑制素合成的部位、分子结构及生理作用已经有了深入的认识,利用蛋白质分离及分子原位杂交技术已人工合成了牛、羊、人的重组抑制素,固相合成技术已成功地合成了有功能的α片段N端  相似文献   

4.
抑制素主要是由雄性动物的睾丸支持细胞和雌性动物的卵泡颗粒细胞所分泌的一种糖蛋白。它由2个二硫键将1个α亚基和1个β亚基连接而成,分子量3.1万~10万。不同种属动物的抑制素,其分子结构极为相似。公畜抑制素主要是选择性地抑制FSH的分泌,并与睾酮具有协同作用。  相似文献   

5.
抑制素具有抑制垂体分泌FSH的作用,文章主要综述抑制素对雄性动物生殖和雌性动物生殖作用。  相似文献   

6.
抑制素对动物生殖系统的影响及其在动物生产中的应用   总被引:1,自引:1,他引:0  
抑制素是转化生长因子β超家族成员之一,是由α亚基和β亚基构成的异二聚体,主要由卵泡颗粒细胞和睾丸支持细胞分泌,在生殖系统的功能主要是通过调节FSH合成和分泌发挥的。作者就抑制素的分布与结构、在雌雄动物生殖系统的表达及功能、在动物生产中的应用进展进行综述。  相似文献   

7.
抑制素是由性腺分泌的糖蛋白激素,在生理状况下能抑制雄性动物垂体选择性地合成和分泌FSH,从而抑制精子的发生,进而影响雄性动物的繁殖力,本文结合雄性动物睾丸结构和精子发生特点,阐述了抑制素对雄性动物精子发生作用及可能的作用机理,进一步表明抑制素与精子发生有着密切的关系,在睾丸发育和精子生成等过程中扮演着重要角色,为临床动物雄性不育的诊断和治疗提供理论基础。  相似文献   

8.
抑制素是一种由性腺分泌的糖蛋白,由α、β两个亚基组成。研究表明,它具有选择性抑制促卵泡素(FSH)合成和分泌的作用。最初在研究抑制素生理作用时发现,用卵泡液提取物免疫动物后,可提高排卵率,增加产仔数。另一方面的研究发现,在多产Booroola美利奴母羊卵巢中缺少具生物活性的抑制素,这说明这种母羊体内FSH浓度较高,这显然是由于该种母羊卵巢内缺少抑制素的结果。  相似文献   

9.
抑制素对公畜生殖的影响   总被引:4,自引:0,他引:4  
1 研究史 1932年,Mecullagh 等人首次在牛睾丸网液中发现了一种具有抑制因曲细精管损伤而使垂体出现去势细胞的活性物质, 命名为抑制素(inhibin). 到七十年代,人们又相继在羊睾丸网液以及牛、猪、马、鼠、猴及羊等动物和人的卵泡液中发现了抑制素.此后,随着研究工作的不断深入,人们已从牛、猪、羊等动物的卵泡液中分离纯化了抑制素,并用cDNA技术对抑制素的分子结构和理化性质进行了较为详细的研究和阐述.人们已经能用放射免疫分析的方法对多种动物体内的抑制素含量进行准确的测定. 近年来,国外学者在大鼠、仓鼠、猪、牛、绵羊、猴等动物抑制素的广泛研究,证明抑制素免疫对动物生殖功能的重要调节作用和由此提高动物繁殖力的潜能.本校1996届硕士研究生刘玉清,用纯化的猪抑制素对母山羊进行主动免疫,证明这种免疫能显著提高排卵率和血浆FSH水平,对动物生殖功能有重要的调节作用.在公畜,抑制素对FSH的分泌有负反馈作用.  相似文献   

10.
抑制素(Inhibin)是一种由性腺器官分泌的糖蛋白激素,能抑制垂体促卵泡素(FSH)的分泌及卵泡发育。本文主要阐述抑制素基因免疫对动物繁殖力的影响及影响免疫效果的因素。  相似文献   

11.
Heartworm in dogs in Canada in 1984   总被引:4,自引:4,他引:0       下载免费PDF全文
In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

  相似文献   

12.
13.
Heartworm in dogs in Canada in 1983   总被引:6,自引:6,他引:0       下载免费PDF全文
In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.

  相似文献   

14.
15.
In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.  相似文献   

16.
Heartworm in dogs in Canada in 1985   总被引:3,自引:3,他引:0       下载免费PDF全文
In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

  相似文献   

17.
Heartworm in dogs in Canada in 1988   总被引:1,自引:1,他引:0       下载免费PDF全文
In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).  相似文献   

18.
Heartworm in dogs in Canada in 1989   总被引:1,自引:1,他引:0       下载免费PDF全文
In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

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19.
Heartworm in dogs in Canada in 1987   总被引:1,自引:1,他引:0       下载免费PDF全文
In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).  相似文献   

20.
Heartworm in dogs in Canada in 1986   总被引:2,自引:2,他引:0       下载免费PDF全文
In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

  相似文献   

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