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Zhang B Wei Q Shi S Dong F Shi F Xu Y 《The Journal of reproduction and development》2012,58(4):410-419
Gpr3, a member of the G protein-coupled receptor superfamily, was known as a critical factor for the maintenance of meiotic prophase arrest in oocytes via a Gs protein-mediated pathway. The present studies were conducted to examine the ovarian immunolocalization of Gpr3, its expression pattern in different stages of fetal, postnatal and developmental pigs and its effect on proliferation of ovarian granulosa cells in pigs. Immunohistochemical analysis indicated that Gpr3 was localized in egg nests, oocytes and granulosa cells (GCs) of the follicle ranging from the primordial to Graafian stages and the corpora lutea. Staining was faintly present in the corpora lutea and weak in GCs but was strong in oocytes. Real-time PCR and Western blotting indicated that Gpr3 mRNA and protein were both present in the different ages of ovaries, and there were wavy changes in the expression levels from postpartum 1 to 180 days. Moreover, both the mRNA and protein levels of Gpr3 were upregulated significantly during follicle growth, suggesting that Gpr3 might play potential roles in regulating ovarian follicle development in the pig. MTT and flow cytometry analyses indicated that Gpr3 knockdown significantly promoted proliferation of porcine GCs while increasing the proportion of cells in the S phase and the expression of Cyclin B1 and Cyclin D2, providing new insights into how Gpr3 signaling regulates the proliferation of porcine GCs. In conclusion, the stage- and cell-specific expression pattern of Gpr3 in the porcine ovary suggested that Gpr3 might play an important role during the entire process of follicular development and luteinization. 相似文献
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地表能量分配是土地利用/覆被变化(LUCC)调控气候的关键过程.以吉林省1990年、2000年、2005年和2010年四期土地覆被数据为基础,利用SiB2分析过去20年LUCC对地表能量分配的影响.结果表明:1)地表能量分配各分量与土地利用类型有良好的空间对应关系,森林获得的净辐射、显热和潜热较多,农田和草地的净辐射、显热和潜热通量较小;2)LUCC过程中,叶面积指数是净辐射的重要影响因素,冠层导度主要调节潜热分配;3)吉林省土地利用变化以“森林和草地转换为农田”过程为主,造成年均净辐射降低了0.22W m-2,潜热增加了0.56W m-2,显热减小了0.83W m-2,且均存在季节变化特征. 相似文献
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In building Samoan academic researcher capacity in Samoa, we argue that there is a need to first establish the kind of researcher community advocated by Linda Tuhiwai Smith, and to do so through developing research tools, such as the talanoa and faafaletui, in partnership with researcher capacity‐building initiatives such as the applied postgraduate social and health research methods course (coded PUBX731‐HSA505) run by the Centre for International Health, University of Otago, in partnership with the National University of Samoa. This paper offers a commentary on the talanoa and faafaletui as Pacific research methodologies, and asks what its value might be for researchers in Samoa. It reflects on the learning experiences of staff and students of the applied social and health research methods course in relation to the talanoa and faafaletui as Pacific research methodologies or methods. It concludes that developing Pacific research and researcher capacity in Pacific Island countries, such as Samoa, must include opening up spaces within these communities to critically engage what is Pacific or Samoan or indigenous about these research tools, methods or methodologies, and how they might differ in form or substance from other methods or methodologies. 相似文献
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融合面向对象与缨帽变换的湿地覆被类别遥感提取方法 总被引：2，自引：2，他引：0
为了有效提取湿地覆被类别遥感信息,该文基于国产环境星影像(HJ-CCD)和Landsat7遥感影像(ETM)提出了一种融合面向对象技术和缨帽变换的提取湿地覆被信息的方法,并对东洞庭湖区的湿地进行提取。遥感提取结果的总体精度90.02%,Kappa系数0.88,高于传统的分类方法分类的量化结果;获得的结果没有"椒盐现象"且比较紧致。试验结果表明融合面向对象和缨帽变换的方法能够有效的提取湿地覆被类别,精度高,效果好。研究结果为有效地利用遥感手段提取湿地覆被信息提供参考。 相似文献
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Ecosystem sensitivity to acid deposition can be a basis for thederivation of cost-effective strategies to sulfur and nitrogenpollutant control, consequently is widely concerned around theworld. In the article, the relative sensitivity of terrestrialecosystem to acid deposition in South China is assessed andmapped using a new sensitivity classification system suitable tosubtropical ecosystem. The result shows that the distribution ofecosystem sensitivity to acid deposition in South China isalmost zonal, on the whole, sensitivity increases from the northand west to the south and east. The most sensitive areas are thenorthwest and southeast of Zhejiang province, the central partof Fujian province, and the northeast of Guangdong province andGuangxi Zhuang Autonomous Region, which are all in the old acidsoil areas with high precipitation and coniferous forests. Theresulting distribution of sensitive regions is different othermaps, including the sensitivity map which is implemented in theRAINS-Asia model. 相似文献
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为减少抗逆分子育种中因引入外源抗性基因造成的基因多效性,降低外源基因对植物的伤害,本研究设计并合成逆境响应顺式元件不同组合的启动子,将其连上GUS报告基因后转化为拟南芥野生型Col-0;通过转基因拟南芥中GUS报告基因的表达强度分析各种启动子对干旱和盐害的响应情况,筛选出了在正常条件下无渗漏、在干旱和盐害胁迫下被诱导的启动子AXpro。然后,利用发根农杆菌介导转化大豆,发现干旱诱导生物钟基因GmTIC的沉默能提高大豆的抗旱能力。研究结果为农林业的抗逆分子育种提供了理论基础和应用方法。 相似文献
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为研究胆绿素还原酶A(Biliverdin reductase A,BLVRA)基因的遗传分化,探索其结构和功能,根据鸡、人、小鼠、牛等动物BLVRA基因编码区的保守序列设计一对引物,以缙云麻鸭输卵管子宫部的总RNA为模板,利用RT-PCR技术扩增出鸭BLVRA基因的一段cDNA编码序列,并对其进行测序及序列分析。结果表明:该cDNA序列由634个核苷酸组成,编码211个氨基酸,分子量为24.1ku。与鸡、小鼠、牛、蟾蜍和人的核苷酸相似性分别为92.6%、64.9%、62.8%、69.0%、63.6%;氨基酸的相似性分别为96.2%、59.7%、60.7%、68.4%、59.7%,说明BLVRA基因在进化过程中较为保守。进一步的系统进化分析表明,鸭BLVRA基因与鸡的进化关系最近,蟾蜍次之,小鼠、牛和人较远,与传统的分类地位基本吻合。该基因部分cDNA序列的克隆,为获得BLVRA基因全长及其在各组织中的表达研究奠定了基础。 相似文献
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The critical loads of SO2 dry deposition in South China,which is transferred from critical level, as well the excess ofcritical loads are computed and mapped. The areas with thelowest critical load and the highest excess are, respectively,identified. The research is complementary to the previousresearches on critical loads for soils, and expected to beintegrated with them to make efficient sulfur emission abatement strategy. 相似文献
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基于无线传感器网络的温室环境监测系统研究 总被引：2，自引：0，他引：2
温室环境监删采用基于ZigBee技术的无线传感器网络有着明显的优势.ZigBee网络容量大、功耗低、易于扩充并且支持自组织组网.设计了一种基于ZigBee的温室环境监测系统,简述了ZigBee的特点及温室环境监测系统的特点,包括网络协调器节点和传感器节点的硬件和软件设计.该设计可构架一个较大范围的无线传感器网络,对温室... 相似文献