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31.
选取21日龄断奶长白仔猪37头,按表皮生长因子(EG F)、胰岛素样生长因子-Ⅰ(IG F-Ⅰ)、基础日粮、自然哺乳随机分为4组,每组3重复,每个重复3头。EG F和IG F-Ⅰ的剂量为17.86μg/d,研究其对早期断奶仔猪免疫功能的影响。结果表明:EG F组和IG F-Ⅰ组脾淋巴细胞转化率均极显著(P<0.01)高于基础日粮组,空肠后段肠黏膜SIgA含量极显著(P<0.01)高于基础日粮组而且EG F组脾淋巴细胞转化率高于IG F-Ⅰ组。EG F组小肠各段黏膜上皮间淋巴细胞数极显著(P<0.01)高于基础日粮组;IG F-Ⅰ组空肠和回肠黏膜上皮间淋巴细胞数极显著(P<0.01)高于基础日粮组;EG F组回肠黏膜上皮间杯状细胞数极显著(P<0.01)高于基础日粮组;IG F-Ⅰ组回肠黏膜上皮间杯状细胞数极显著(P<0.01)低于自然哺乳组。表皮生长因子和胰岛素样生长因子-Ⅰ能提高早期断奶仔猪的免疫功能。  相似文献   
32.
以水貂的表皮生长因子基因(EGF)作为候选基因,采用单链构象多态性和DNA测序的方法检测了EGF基因单核苷酸多态性(SNPs)。针对该群体的特点建立合适的统计分析模型,并进行了EGF基因多态性与皮长性状的关联分析。结果表明,EGF基因对水貂的皮张长度有一定影响。BB基因型个体与AA基因型个体之间有一定的差异(P<0.05)。CD基因型个体皮长平均要高于CC和DD基因型,且与CC型个体差异显著(P<0.05),与DD型差异不显著(P>0.05)。统计各基因型之间的组合给水貂皮长带来的影响时,发现多数组合基因型对所检测的水貂皮长有显著影响(P<0.05)。  相似文献   
33.
山羊卵母细胞的体外成熟研究   总被引:9,自引:0,他引:9  
1.比较了在卵母细胞成熟液中添加相同浓度(10ng/ml)的表皮生长因子(EGF),胰岛素样生长因子(IGF),EGF IGF后,不同生长因子对卵母细胞体外发育率的影响。结果表明,在成熟培养液中添加EGF后,其卵母细胞的成熟率(70.9%)与对照组(67.3%)相比有所提高,但差异不显著;在成熟培养液中分别添加IGF、EGF IGF,其卵母细胞的成熟率分别为80.0%,82.4%,显著高于对照组卵母细胞的成熟率(67.3%)。2.比较了不同季节采集的卵母细胞在体外成熟的情况。结果发现,12月份到来年的1月份,采集的卵母细胞,其体外成熟率最高,为81.0%;11月份采集的卵母细胞,其体外成熟率次之,为74.1%;3—5月份和9—10月份采集的卵母细胞,其体外成熟率为66.0%、69.6%;6—7月初采集的卵母细胞,其体外成熟率最差,为54.7%。3.比较了OM液pH值对卵母细胞体外成熟的影响。当OM培养液的pH值为7.2和6.8 ̄7.0时,卵母细胞成熟率的为66.2%和61.0%,显著高于pH≥7.5时的成熟率(50.9%,P<0.05)。  相似文献   
34.
HMG、EGF和TGF-α对猪卵母细胞体外成熟及发育的影响   总被引:2,自引:1,他引:1  
以TCM199为基础培养基,HMG(尿促性素)为激素,探讨了HMG在猪卵母细胞体外成熟(IVM)和发育中的影响;同时对EGF(表皮生长因子)和TGF-α(转化生长因子-α)单独或联合使用对猪卵母细胞IVM及发育的影响进行了研究,以确立猪卵母细胞IVM较好的培养体系。结果表明:①在猪卵母细胞IVM中分别添加0.075、0.15、0.2、0.3 IU/mL的HMG,其中添加0.2 IU/mL的HMG组卵母细胞的成熟率和激活后的卵裂率显著高于其它组,差异显著(P<0.05);②添加50 ng/mL的EGF组成熟率和卵裂率高于对照组和添加30、40、60 ng/mL组,差异显著(P<0.05);③添加15 ng/mL的TGF-α组成熟率高于对照组和添加5、40ng/mL组,有显著差异(P<0.05),激活后卵裂率添加15 ng/mL组显著高于其他组(P<0.05),当TGF-α的浓度高于15 ng/mL后对卵母细胞的成熟和激活后的卵裂没有显著的提高作用;④同时添加EGF和TGF-α组成熟率和卵裂率与对照组相比差异显著(P<0.05),但与添加50 ng/mL EGF、15 ng/mLTGF-α组相比没有明显不同(P>O.05)。可见EGF和TGF-α对猪卵母细胞的IVM和激活后的卵裂没有明显的协同作用。  相似文献   
35.
Pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), play fundamental roles in vertebrate ovarian development and function. However, there has been an increasing body of evidence that the actions of FSH and LH are mediated or modulated by a variety of locally produced peptide or protein factors, which form an intimate regulatory network within and between the ovarian follicles. In the past few years, a variety of growth factors have been identified and characterized in the zebrafish ovary including activin and epidermal growth factor (EGF), which are important components of the intraovarian communication network. To understand how this local network interacts with the gonadotropins from the pituitary, we have recently cloned and characterized all the subunits of zebrafish FSH and LH from the pituitary as well as their receptors (FSHR and LHR) from the ovary. Using the Chinese hamster ovary (CHO) cells as the bioreactor, we have produced recombinant zebrafish FSH and LH with biological activities. With the recombinant hormones available, the functions of zebrafish FSH and LH in the ovary and their interactions with the local factors will be an important issue to address in the future. This review briefly summarizes some recent work from our laboratory and others on both gonadotropins and their potential intraovarian signaling factors in the zebrafish.  相似文献   
36.
[目的]为优化幼畜卵母细胞体外培养体系提供理论基础。[方法]研究在成熟液中添加EGF和β-巯基乙醇对绵羔羊卵母细胞受精和卵裂、囊胚情况的影响,并与成年绵羊卵母细胞进行比较。[结果]在成熟液中添加不同浓度的EGF对羔羊卵母细胞卵裂率和囊胚率无显著影响(P0.05)。添加不同浓度的β-巯基乙醇可以提高羔羊卵母细胞囊胚率,其中添加100μmol/Lβ-巯基乙醇有显著影响(P0.05),但对卵裂率影响不显著(P0.05)。羔羊卵母细胞卵裂率和囊胚率均显著低于成年羊(P0.05)。添加100μmol/L的β-巯基乙醇能显著提高羔羊卵母细胞正常受精率(P0.05),且与成年羊卵母细胞受精率差异不显著(P0.05)。未添加β-巯基乙醇多精入卵率显著高于成年羊(P0.05),而添加100μmol/L的β-巯基乙醇多精入卵率与成年羊差异不显著(P0.05)。成熟液中不添加β-巯基乙醇时未受精率(20.0%)高于成年羊组(12.3%)和β-巯基乙醇(13.5%),但差异不显著(P0.05)。[结论]添加100μmol/L的β-巯基乙醇能显著提高羔羊卵母细胞发育能力,提高正常受精的比例并减少多精子受精的发生,但羔羊卵母细胞发育能力仍显著低于成年羊。  相似文献   
37.
摘要:ESR、FSHβ和EGF基因与猪繁殖性状密切相关。为检测军牧1号白猪、西藏小型猪、杜洛克猪和失白猪ESR、FSHβ和EGF基因的多态性分布情况,采用PCR和PCRRFLP的方法对61头军牧1号白猪,51头杜洛克猪,51头西藏小型猪和69头大白猪的ESR、FSHβ和EGF基因多态性进行了检测。结果显示,对于各个基因的优势等位基因,在军牧1号白猪群体中,ESR基因位点A等位基因频率为0.6393,FsHp基因的13等位基因频率高达0.9098,EGF基因的A等位基因频率仅有0.0164杜洛克猪群体中,ESR基因A等位基因频率为0.6078,FSHβ基因的B等位基因频率为0.8235,而EGF基因的八等位基因频率仅为0.0297;西藏小型猪群体中,ESR基因A等位基因频率是0.4608,FSHβ基因B等位基因频率仅为0.0687,H;F基因A等位基因频率为o.1961;大白猪群体中。ESR基因位点有频率为0.5000的有害A等位基因,而FSHβ基因和EGF基因的13等位基因频率则分别为0.8013和0.7391。所有基因型分布均符合哈代温伯格平衡(P〉0.05)。  相似文献   
38.
EGF和IGF-1对山羊卵母细胞体外成熟的影响   总被引:3,自引:0,他引:3  
研究了在培养液中添加不同浓度的EGF、IGF-1以及EGF联合IGF-1对山羊有腔卵母细胞体外成熟的影响。结果表明: (1)10, 20, 30μg/LEGF对山羊卵母细胞体外成熟无显著影响(P>0.05)。(2) 10μg/L的IGF-1对山羊卵母细胞体外成熟无显著影响(P>0.05); 20, 30μg/L的IGF-1能显著提高山羊卵母细胞体外成熟率 (P<0.05)。(3)添加 10μg/LEGF+20μg/LIGF-1组卵母细胞体外成熟率显著高于添加 20μg/L的IGF-1组(P<0.05),极显著高于添加 10μg/LEGF组和对照组(P<0.01)。可见,EGF和IGF-1对山羊卵母细胞体外成熟有协同作用。  相似文献   
39.
The study investigated the effects of epidermal growth factor(EGF) and insulin-like growth factor 1(IGF-I),alone or together,on the in vitro maturation and cleavage of ovine oocytes,aimed to optimize the in vitro maturation conditions for ovine oocytes.The results showed that the maturation and cleavage rates were 71.2% and 45.5% respectively when the medium was supplemented with 50 ng/mL EGF alone,which was significantly higher than other EGF supplemented groups (0,10,20,30,and 40 ng/mL) (P<0.05).The highest maturation and cleavage rates were 72.9% and 45.7% when the EGF concentration reached 100 ng/mL.The maturation and cleavage rates were 70.7% and 58.5% with 40 ng/mL IGF-I supplemented,which were significantly higher than other treatments (0,10,20,60,80,and 100 ng/mL) (P<0.05).The lowest maturation and cleavage rates were 38.8% and 20.0% when the IGF-I concentration reached 100 ng/mL (P<0.05).When 50 ng/mL EGF and 40 ng/mL IGF-I were used concomitantly,the maturation and cleavage rates were 85.6% and 61.0% respectively,which were significantly higher than the treatments with EGF or IGF-I alone (P<0.05).  相似文献   
40.
This study examined the influence of EGF on the expression of EGF receptors (EGFR) and developmental competence of embryos cultured individually versus those cultured in groups. Cat oocytes were in vitro matured and fertilized (IVM/IVF), and cleaved embryos were randomly assigned to one of seven culture conditions: one group each in which embryos were subjected to group culture supplemented with or without 5 ng/ml EGF and five groups in which embryos were subjected to single-embryo culture supplemented with EGF (0, 5, 25, 50 or 100 ng/ml). Morulae, blastocysts and hatching blastocysts were assessed at days 5 and 7; post IVF, respectively, and total blastocyst cell numbers were assessed at day 7. Relative mRNA expressions of EGFR of 2–4-cell embryos, 8–16-cell embryos, morulae and blastocysts cultured in groups or singly with or without EGF supplementation were examined. OCT3/4 and Ki67 in blastocysts derived from the group or single-embryo culture systems with or without EGF supplementation were localized. A higher rate of embryos cultured in groups developed to blastocysts than individually incubated cohorts. Although EGF increased blastocyst formation in the single-embryo culture system, EGF did not affect embryo development in group culture. Expression levels of EGFR decreased in morulae and blastocysts cultured with EGF. An increased ratio of Ki67-positive cells to the total number of cells in the blastocyst was observed in singly cultured embryos in the presence of EGF. However, EGF did not affect the expression of OCT3/4. These findings indicate that EGF enhanced developmental competence of cat embryos cultured singly by stimulating cell proliferation and modulating the EGFR expression at various developmental stages.  相似文献   
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