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31.
The aim of this study was to document the expression and localization of VEGF system comprising of VEGF isoforms (VEGF 120, VEGF 164 and VEGF 188) and their receptors (VEGFR1 and VEGFR2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors. In general, all the components of VEGF system (the VEGF isoforms and their receptors) were found in the water buffalo CL during the oestrous cycle. The mRNA as well as protein expression of VEGF system was highest during the early and mid‐luteal phase, which later steadily decreased (p < 0.05) after day 10 to reach the lowest level in regressed CL. As demonstrated by immunohistochemistry, VEGF protein was localized predominantly in luteal cells; however, VEGFR1 and VEGFR2 were localized in luteal cells as well as in endothelial cells. In conclusion, the dynamics of expression and localization of VEGF system in buffalo corpora lutea during the luteal phase were demonstrated in this study, indicating the possible role of VEGF system in the regulation of luteal angiogenesis and proliferation of luteal as well as endothelial cells through their non‐angiogenic function.  相似文献   
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The role of opioid peptides in the secretion of oxytocin (OT) and prolactin (PRL) induced by sucking was studied in goats. Seven goats were isolated with their kids (four singletons and three twins) in individual corrals 3–4 weeks after parturition. On day 1 of the experiment, the kids were separated from the does for 7 h and were weighed before and 15 min after being reunited with their mothers to assess the amount of milk obtained by sucking. The does were blood‐sampled 10 min before and at the end of the sucking period. On day 2, a similar protocol was followed, but naloxone was given immediately after the first blood sample. On day 3, the protocol was repeated but saline vehicle was injected instead of naloxone. On day 5, the naloxone experiment was repeated as on day 2. Milk ejection was evaluated as the difference in the weight of the kids before and after sucking for 15 min, and the maternal serum levels of OT and PRL were measured by radioimmunoassay. A significant decrease in the weight gain of the kids was obtained when the mothers were treated with naloxone on day 2. Consistently, serum levels of OT and PRL induced by sucking were significantly reduced; indicating that sucking‐induced OT secretion for milk ejection in lactating goats is facilitated by opioid peptides. In a second experiment performed in the same animals 10 days later, the administration of OT, immediately after naloxone administration, prevented the decrease in the weight gain induced by naloxone, suggesting that the effect of the opioid antagonist on milk ejection in goats is a result of a reduced OT secretion. The results of this study confirm the importance of sucking‐induced OT secretion for milk ejection in lactating goats, and indicate that OT and PRL secretion are regulated by opioid peptides in this species.  相似文献   
33.
 利用26对黄牛微卫星引物,对分别来自云南省泸水县凤凰山大额牛保种区和贡山县独龙野牛种源保护基地的2个大额牛群体进行遗传变异分析,研究其群体内的遗传变异和群体间的遗传分化。结果共检测到105个等位基因,每个座位的等位基因数从2~6不等,所有座位平均等位基因数、平均有效等位基因数、平均期望杂合度、平均多态信息含量分别为4.0385±0.9999,3.1393±0.9507,0.6490±0.1246和0.5904±0.1334,表明大额牛群遗传多样性比较丰富。F统计量、基因流、Nei氏遗传距离和遗传相似系数等值反映出两个群体遗传差异较小,遗传分化不明显,遗传一致性较大。  相似文献   
34.
通过对宜丰县云峰尖林场毛竹示范林的经营状况进行调查,分析了其经济效益、社会效益、生态效益。  相似文献   
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【目的】量化环境要素对山西省中条山油松Pinus tabuliformis人工林下物种分布影响,为进一步揭示中条山油松人工林下物种多样性维持机制提供理论依据。【方法】基于中条山油松人工林样地植物和土壤调查数据,分析环境因子对油松人工林下物种分布的影响。【结果】环境因子对灌木、草本、藤本物种分布的解释率(校正解释率)分别为45.7%(34.5%)、37.0%(20.4%)、43.4%(30.6%);油松林下物种分布主要受非生物环境影响,海拔和土壤通气性是影响该地区物种分布的关键环境因子;灌木和藤本分布主要受海拔影响,草本分布主要受土壤通气性影响,且随着海拔、土壤通气性的升高油松人工林下物种多样性下降。【结论】地形(海拔)和土壤(土壤通气性)因子对区域群落生境的关键塑造作用所形成的环境筛是影响中条山油松人工林下物种分布的关键性因子。图1表5参39  相似文献   
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2001~2005年,引种8个山葡萄种内和种间杂交品种的试验结果表明:筛选出适宜当地气候和土壤条件、抗寒、产量高、可酿造干红葡萄酒左优红、加工果汁饮料的哈桑、用于调色和调酸的双优和双红,为当地主栽和推广品种。  相似文献   
39.
为揭示不同基因型烤烟的光合特性,通过大田试验,利用LI-6400XT光合测定系统测定了毕节烟区4种主栽品种上部叶片的光、CO2的响应曲线,分别利用Farquhar模型和直角双曲线模型拟合光、CO2曲线,阐述了4个品种光响应和CO2响应特征及其主要参数.结果表明,4个品种响应曲线规律基本一致,响应特征参数差异明显.云烟97对高光照的适应能力相对最强、碳同化能力也表现较好;K326则表现出对弱光和低摩尔分数CO2的利用效率,对环境适应能力较强;毕纳1号饱和CO2速率明显高于其余品种,具有一定的高产潜力;红花大金元的优势体现在自身碳同化过程中的羧化效率.高海拔区域,选择种植云烟97能发挥其适应高光照的优势;中低海拔区域,K326和毕纳1号适应性较好,且能更好地发挥其生产潜力.  相似文献   
40.
采用田间随机区组法研究甘南高原独一味间作栽培藏木香对独一味出苗率、成活率、叶长、叶宽和株高的影响。结果表明,独一味间作栽培藏木香时,当年生独一味的出苗率、成活率比单作极显著提高;两年生独一味的叶长、叶宽和株高的生长变化也比单作显著加快。该研究攻克了独一味大田栽培中成活率低的技术难关,对独一味的人工栽培有一定的指导意义。  相似文献   
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