Results 51 to 60 of about 1,669,777 (177)
文章对维吾尔族的JC病毒IG区域基因型的地理分布状况进行了对比研究。从103个40岁以上的男性尿样提供者中分离出了JC病毒,并且对它们进行了DNA提取,对JC病毒IG区域进行了PCR扩增和DNA序列测定,得到了73人的JC病毒DNA IG区域的碱基序列。多态分析研究结果表明,73人中的基因型分别由B1-a,B1-b,B1-c,CY和EU组成,各基因型所占比率为:4.1%,58.9%,8.2%,21.9%和2.7%。研究发现,在各基因型中B1-b型和CY型所占的比率高 ...
艾山江·阿布都拉 +2 more
core
目的观察雌激素受体(ER)α和β基因多态与绝经后女性代谢综合征(MS)的关系。方法 311例无亲缘关系的绝经后MS患者和231例年龄相匹配的健康对照人群,采用聚合酶链反应-限制性片段长度多态性(PCRRFLP)技术,检测ERα(XbaⅠ、PvuⅡ)和β基因(RsaⅠ、AluⅠ)多态性,并采用SHEsis在线计算平台进行统计学分析。结果与对照组相比,MS患者体重、BMI、SBP、DBP以及血清FBS、GSP、TG水平显著高于对照组,而HDLC水平显著低于对照组(P0.05);对照组和MS组RR、Rr ...
孙树凯 +5 more
doaj
ABSTRACT The move from unipolarity to a fluid and contested multipolar world order has significantly changed the way African nations form national security policy due to changes in the nature of the strategic environment of those states. Much of the literature has focused on how the actions of major world powers ‐ the United States, China and Russia ...
Chick Edmond +2 more
wiley +1 more source
水分亏缺和土壤肥力低下是限制旱地小麦生产的两个重要因素。在有限的水分和养分的条件下,提高小麦自身的水分和养分利用效率是解决这一问题的关键。一些报道证明,水分和养分供应对小麦的水分、养分利用效率有显著作用。目前的研究多以现代栽培品种为材料,有可能遗失了一些古老品种的优良特性。为此本文选取了6个在进化中典型的基因型小麦为材料,在不同水肥条件下对其水分、养分利用效率及相关生长、生理指标进行了测定,以探索小麦水分、养分利用的进化关系和水肥条件对它们的影响。主要结果如下: 1.
黄明丽
core
Habitat and spatial trends of U.K. wintering waterbird populations over 50 years
Abstract The United Kingdom is an important wintering ground for millions of waterbirds. Most U.K. wintering waterbird populations increased between 1970 and the mid‐1990s, but declined thereafter. We examined U.K. population indices in 46 wintering waterbird species in two 25‐year periods, 1970–1994 and 1995–2019, to identify which waterbird groups ...
Blaise Martay +8 more
wiley +1 more source
IL-23R基因多态性与五邑地区汉族人群强直性脊柱炎的相关性分析
目的探讨中国五邑地区汉族人群中白细胞介素(interleukin,IL)-23R基因多态位点与强直性脊柱炎(ankylosing spondylitis,AS)发病的相关性。方法选取该地区汉族人群AS患者50例和同期健康体检者70名,采用Sequenom MassArray基因分型方法检测IL-23R基因多态位点,计算等位基因及基因型频率分布,并进行统计学分析。结果 rs10489629位点基因型频率和等位基因频率在两组间分布存在显著差异(χ2=11.392,P=0.003;χ2=13.435,P=0 ...
李秀娟 +5 more
doaj
Scientists’ warning on the global destruction of rock outcrop ecosystems
Abstract Rock outcrops are geological formations that harbor a highly specialized biota adapted to harsh environmental conditions that differ from their surrounding landscapes. They are globally distributed, especially in old, highly weathered landscapes, and can function as habitat islands containing high levels of endemism and distinct evolutionary ...
Luiza F. A. de Paula +19 more
wiley +1 more source
采用聚丙烯酰胺梯度凝胶电泳及特异性组织化学染色技术分析了鲤、鲫及其基因组叠加的不同组合个体的红细胞SOD. EST和血红蛋白的电泳图谱。结果表明不同基因组组合及不同倍性的个体间存在由基因组差异导致的生化多态性,为不同倍性的鱼类的同工酶(SOD)表达存在基因剂量效应提供了依据,证实了不同组合的SOD亚基间有协同表达、累积作用。研究表明每个基因有其独特的调控机制,因而在杂种三倍体内三分之一的基因组亦能够表达产物。应用本研究的遗传学数据有益于构建基因组特异性品系 ...
吴玉萍,叶玉珍,吴清江
core
Abstract Ecological niche models (ENMs) are used to assess the abiotic preferences of species by linking their occurrences to the environmental conditions in which they live. We developed a fossil‐informed ENM framework that integrates mid‐Holocene and modern occurrences to test niche stability and reconstruct abiotic niche characteristics for four ...
Claire. M. Williams +3 more
wiley +1 more source
以生长于田间的玉米掖单13(耐旱基因型玉米)和丹玉13(不耐旱基因型玉米)为试验材料,应用ICP对供试玉米的初生根和第一、二、三、四、五、六、七、八和第九层次生根的大量元素氮、磷、钾、钙和镁等项指标进行了测定和比较分析。结果表明:除个别根外,耐旱基因型玉米不同类型根中的全氮含量和速效氮含量极显著低于不耐旱基因型玉米根系(P0 ...
宋凤斌, 刘胜群, 王晓波
core

