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91.
Yuan Meng-yi Chang Di Xie Tong-tong Sheng Xi-hui Feng Zi-yan Fu Bo-fan Li Qian-ru Liu Fang Guo Yong Ding Jin Wang Xiang-guo Ni He-min 《东北农业大学学报(英文版)》2021,28(1):61-74
WNT7A and β-catenin localisations and roles in regulating periimplantation ovine conceptus development under natural estrous conditions have been elaborated.However,their locations and expression patterns have not been reported under induction of oestrus.The localisation,expression and function of WNT7A and β-catenin in the uterine tissues of the early pregnant and non-pregnant sheep on days 10,12,14,16 and 18 following artificial induction of oestrus were investigated by means of in situ hybridisation,real-time RT-PCR,immuno-histochemistry and western blotting methods.WNT7A and β-catenin mRNA and protein were both restricted to the apical surfaces of the uterine luminal epithelium (LE) and glandular epithelium (GE).In pregnant sheep,protein localisation of WNT7A and β-catenin was observed both in the endometrial LE and GE.Their staining presented on day 10,increased between day 12 and day 16,and decreased on day 18.WNT7A and β-catenin mRNA and protein expression increased initially and then decreased from day 10 to day 18,peaking on day 16,and β-catenin reaching a peak on day 18 in the uterine tissues of pregnant sheep (p0.05).By contrast,no significant changes in WNT7A and β-catenin mRNA and protein expression levels were observed from day 10 to day 18 of the oestrus cycle in the uterine tissues of non-pregnant sheep (p0.05).Additionally,WNT7A and β-catenin mRNA and protein expression levels in the uterine tissues of the early pregnant sheep were significantly higher than those of non-pregnant sheep (p0.05).Treatment of endometrial epithelial cells with WNT7A increased the mRNA expressions of β-catenin,c-myc and Cyclin D1.These results provided an underlying mechanism of periimplantation ovine conceptus development under induction of oestrus. 相似文献
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崩岗土体的收缩开裂受到多种因素的影响。该研究为研究高径比对其影响,共设计10组高径比,通过定点拍照记录脱湿前与脱湿结束时的土体形态变化,结合数字图像处理技术进行定量分析,探讨在控制高径比条件下崩岗土体的收缩开裂规律。结果表明:1)崩岗4层土中,过渡层的裂隙性、径向收缩性能最强,砂土层最弱,两者之间的较大差异会严重破坏崩岗土体的稳定性与承载力,促使崩壁崩塌;2)高径比较小的试样裂隙发育显著,径向收缩不明显;高径比较大的试样无裂隙发育,径向收缩显著。其中,4层土由干缩开裂土样过渡至径向收缩土样的高径比具体临界值分别位于:0.147~0.160、0.160~0.183、0.160~0.183、0.134~0.147;3)当高径比相同时,即使高度、直径不一致,但其各裂隙参数、径向收缩率具备相似性,轴向收缩率随厚度的增加而增加;4)随高径比的增加,收缩含水率逐渐增大,开裂含水率逐渐减小,两者之间的差值可以表示脱湿过程中土体产生抗拉强度的大小。收缩开裂裂隙度、宽径比、径向收缩率随高径比的增加整体呈现增大的趋势,其余参数均呈现减小的趋势。其中,4层土中,过渡层的收缩开裂特性受高径比影响最显著,砂土层受影响程度最小。研究结果可为揭示崩岗崩塌机理提供科学依据。 相似文献
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Production of inbred larvae through self‐fertilization using oocytes and cryopreserved sperm from the same individuals after sex reversal in eastern oyster Crassostrea virginica
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The eastern oyster Crassostrea virginica can change sex which makes self‐fertilization possible if sperm can be cryopreserved. In this study, small (~1 year old) and large (~2–3 years old) oysters were biopsied for sperm collection. Survival of the biopsied oysters after 1 year was 50% for small oysters and 17% for large oysters. Oocytes were collected from sex‐reversed females, and self‐fertilized with cryopreserved sperm. Of the 24 cryopreserved samples, 14 individuals had ≤1% fertility when crossed with oocytes from unrelated females, indicating that the cryopreserved sperm had reduced fertility. The other 10 individuals had a fertility of 39 ± 25% when crossed with oocytes from unrelated females (non‐selfing), but showed a significantly lower success of self‐fertilization (12 ± 16%) (P = 0.008), while aliquots of the same oocytes had a fertilization of 83 ± 11% when crossing with fresh sperm. Larvae were produced at day 3 in the self‐fertilized families (12–94% of the fertilized oocytes), and survived to eyed‐larvae stage at days 11–14. Genotyping with 9 microsatellite markers confirmed that the larvae resulted from self‐fertilization in four families. This study demonstrated the feasibility of creating self‐fertilized inbred lines of oysters by use of non‐lethal sperm collection and cryopreservation. 相似文献
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乌鳢 (Channaarguscantor)经济价值较高 ,其养殖规模正日益扩大。本文通过文献和笔者自己的研究 ,阐述已知的乌鳢多发病的病因、病原、症状和防治方法。1 乌鳢败血病雷爱莹等认为该病为嗜水气单胞菌和豚鼠气单胞菌感染所致。前者在普通营养琼脂培养基上2 4h形成边缘整齐 ,表面湿润 ,质地粘稠 ,微凸 ,半透明的圆形菌落 ,其菌体为革兰氏阴性、能运动的短杆菌。豚鼠气单胞菌在普通营养琼脂培养基上 2 4h形成圆形、湿润、表面光滑、边缘整齐、微凸、乳白色的菌落 ,亦为革兰氏阴性能运动的短杆菌。两菌株与氧化酶、过氧化酶… 相似文献
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90年代以来,水产养殖业在品种结构调整过程中,中华鳖养殖异军突起,由于市场和价格的驱动,养殖规模和产量在初期几乎一年翻一番,近年每年增幅也在40%左右。自中华鳖列为单项品种统计以来,全国中华鳖养殖产量为:1993年4427吨;1994年9360吨;1995年17445吨;1996年32004吨;1997年44460吨;1998年61881吨。五年增长13倍,是增幅较大的少数品种之一。广东省1993年中华鳖养殖产量66吨,1998年达到9017吨,增长136倍,速度惊人。浙江省1993年养殖产量109吨,98年达到7026吨,增长63倍。另几个中华鳖养殖大省1998年产量是:湖南省4807吨;… 相似文献
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