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741.
利用27对SSR分子标记对新疆4个野杏群体遗传多样性和遗传结构进行分析,评价新疆野杏遗传多样性水平和分化程度,为新疆野杏合理保护与利用提供科学依据。结果显示:(1)27对SSR引物共检测到431个等位基因(Na),各位点平均等位基因数(Na)和多态性信息含量(PIC)分别为15.96和0.84;物种水平上Shannons信息指数(I)和期望杂合度(He)分别为2.21和0.78。(2)群体水平上等位基因数(Na)、有效等位基因(Ne)、Shannons信息指数(I)、期望杂合度(He)和观察杂合度(Ho)分别为10.98、5.85、1.92、0.79和0.55;其中新源县野杏群体遗传多样性最丰富,巩留县群体遗传多样性最低。(3)基于F统计量分析的遗传分化系数(Fst)为0.05,基因流(Nm)为5.26;分子方差分析显示新疆野杏群体大部分遗传变异来自群体内(95.4%),群体间的遗传变异仅占4.6%。(4)新疆野杏群体遗传距离为0.06~0.49,平均为0.24;遗传相似度为0.61~0.94,平均为0.80;遗传相似度的聚类分析和遗传距离的主坐标分析结果一致,均将供试4个群体划分为两组;Mantel检测显示,新疆野杏群体遗传距离与地理距离无显著相关(r=0.332,P=0.16)。研究表明,新疆野杏资源具有丰富的遗传多样性,群体遗传分化程度较低,群体间遗传距离较小,这与新疆野杏群体的大小和悠久的演化历史以及群体间频繁的基因交流相关。 相似文献
742.
743.
三角洲地区经过近几十年的快速发展,在城市建设方面取得举世瞩目的成就,然而长期积累的生态问题也更加突出,暴露出的空间脆弱性问题日益显著。面对自然基底脆弱、自然灾害扰动趋势增强等因素在时空上的高度叠合,迫切需要提升三角洲地区应对未来不确定性扰动的能力。首先从景观角度分析三角洲地区自然环境的特殊性,提出韧性规划是对现有三角洲地区规划转型的论点,认为鲁棒性、适应性、学习—转化能力是三角洲地区韧性规划的核心能力,系统性、协同性、底线性、预判性是三角洲地区韧性规划的主要思维特征。其次,进一步从优化整体格局、构建流动性载体、加强对韧性技术策略的研究和应用、重视跨尺度协作与管理等方面提出了构建“格局—连通—关键点”的韧性规划框架。最后,阐述韧性规划作为三角洲地区规划转型的新理念,应用于具体案例的空间布局时须以人为本,依托自然环境,以自然流动性为规划导向;须基于预判式过程,充分构想能够应对不同情景的预案;须整合生态智慧与现代技术,明晰兼顾鲁棒性与适应性的功能分区管治体系。 相似文献
744.
745.
Fu Haixia Zhao Jingzhong Xu Lanping Liu Kaiyan Wang Yu Chen Huan Han Wei Wang Jingzhi Wang Fengrong Huang Xiaojun Zhang Xiaohui 《中国科学:生命科学英文版》2019,62(7):921-929
We aimed to measure platelet function and its relationship with β2-GPI in prolonged isolated thrombocytopenia(PT) after allogeneic hematopoietic stem cell transplantation(allo-HSCT). Fifty-six patients with PT and 60 allo-HSCT recipients without PT(non-PT controls) were enrolled. Platelet aggregation and activation, β2-GPI and anti-β2-GPI antibody levels, vWF antigen,and vWF activity were analyzed. The effect of β2-GPI on platelet aggregation was also measured ex vivo. Results showed that ADP-induced platelet aggregation significantly increased(39%±7.5% vs. 23%±8.5%, P=0.032), and the platelet expression of both CD62 p(33.6%±11.6% vs. 8.5%±3.5%, P0.001) and PAC-1(42.4%±7.6% vs. 6.8%±2.2%, P0.001) was significantly higher in patients with PT than in those without PT. Significantly lower β2-GPI levels(164.2±12 μg m L–1 vs. 234.2±16 μg mL–1,P0.001), higher anti-β2-GPI IgG levels(1.78±0.46 U mL–1 vs. 0.94±0.39 U mL–1, P0.001), and increased vWF activity(133.06%±30.50% vs. 102.17%±25.90%, P0.001) were observed in patients with PT than in those without PT. Both ADPinduced platelet aggregation(n=116, r~2=-0.5042, P0.001) and vWF activity(n=116, r~2=-0.2872, P0.001) were negatively correlated with β2-GPI levels. In summary, our data suggested that platelet aggregation and activation were significantly higher in patients with PT than in those without PT, which might be associated with reduced β2-GPI levels. The reduced β2-GPI levels might be due to the existence of anti-β2-GPI IgG. 相似文献
746.
Kyu‐Won Kwak Hong‐Soo Choi Sung‐Hee Nam Myung‐Sae Han Eunsun Kim Kwanho Park Heui‐Sam Lee 《Entomological Research》2019,49(12):534-538
This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification. 相似文献
747.
Li Zhihui Zhu Peng Huang Hui Pan Ying Han Peng Cui Huanhuan Kang Zhijuan Xun Mai Zhang Yi Liu Saijun Wang Jian Wu Jing 《中国科学:生命科学英文版》2019,62(12):1572-1579
Alport syndrome(AS) is a hereditary progressive nephropathy characterized by hematuria, ultrastructural lesions of the glomerular basement membrane, ocular lesions and sensorineural hearing loss. Germline mutations of COL4 A5 are associated with X-linked AS with an extreme phenotypic heterogeneity. Here, we investigated a Chinese family with Alport syndrome. The proband was a 9-year-old boy with hematuria and proteinuria. Based on the test results of renal biopsy and immunofluorescence,the proband was initially diagnosed as Ig A nephropathy and the treatment was recommended accordingly. Meanwhile, we found that the treatment outcome was poor. Therefore, for proper clinical diagnosis and appropriate treatment, targeted exome-based next-generation sequencing has been undertaken. We identified a novel hemizygous single nucleotide deletion c.1902 del A in COL4 A5 gene. Segregation analysis identified that this novel mutation is co-segregated among the affected family members but absent in unaffected family members. The clinical diagnosis of the proband was revised as AS accompanied by Ig A nephropathy,which has been rarely reported. Our findings demonstrated the significance of the application of Genetic screening, expanded the mutation spectrum of COL4 A5 associated AS patients with atypical renal phenotypes and provided a good lesson to be learned from our detour during the diagnosis. 相似文献
748.
QKI‐6 inhibits bladder cancer malignant behaviours through down‐regulating E2F3 and NF‐κB signalling
749.
750.
Yu‐Han Wang Xiao‐Hui Huang Yan‐Mei Yang Youdi He Xiao‐Hui Dong Hui‐Xin Yang Lei Zhang Yan Wang Jin Zhou Changyong Wang Xiao‐Xia Jiang 《Journal of cellular and molecular medicine》2019,23(5):3737-3746
Adipose‐derived stem cells (ASCs) are highly attractive for cell‐based therapies in tissue repair and regeneration because they have multilineage differentiation capacity and are immunosuppressive. However, the detailed epigenetic mechanisms of their immunoregulatory capacity are not fully defined. In this study, we found that Mysm1 was induced in ASCs treated with inflammatory cytokines. Adipose‐derived stem cells with Mysm1 knockdown exhibited attenuated immunosuppressive capacity, evidenced by less inhibition of T cell proliferation, more pro‐inflammatory factor secretion and less nitric oxide (NO) production in vitro. Mysm1‐deficient ASCs exacerbated inflammatory bowel diseases but inhibited tumour growth in vivo. Mysm1‐deficient ASCs also showed depressed miR‐150 expression. When transduced with Mysm1 overexpression lentivirus, ASCs exhibited enhanced miR‐150 expression. Furthermore, Mysm1‐deficient cells transduced with lentivirus containing miR‐150 mimics produced less pro‐inflammatory factors and more NO. Our study reveals a new role of Mysm1 in regulating the immunomodulatory activities of ASCs by targeting miR‐150. These novel insights into the mechanisms through which ASCs regulate immune reactions may lead to better clinical utility of these cells. 相似文献