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91.
High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010–2014 by inclusive composite interval mapping (ICIM) (LOD≥2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82–23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs.  相似文献   
92.
Curcumin, a principle bioactive component of Curcuma longa L, is well known for its anti-hyperlipidemia effect. However, no holistic metabolic information of curcumin on hyperlipidemia models has been revealed, which may provide us an insight into the underlying mechanism. In the present work, NMR and MS based metabolomics was conducted to investigate the intervention effect of curcumin on hyperlipidemia mice induced by high-fat diet (HFD) feeding for 12 weeks. The HFD induced animals were orally administered with curcumin (40, 80 mg/kg) or lovastatin (30 mg/kg, positive control) once a day during the inducing period. Serum biochemistry assay of TC, TG, LDL-c, and HDL-c was conducted and proved that treatment of curcumin or lovastatin can significantly improve the lipid profiles. Subsequently, metabolomics analysis was carried out for urine samples. Orthogonal Partial Least Squares-Discriminant analysis (OPLS-DA) was employed to investigate the anti-hyperlipidemia effect of curcumin and to detect related potential biomarkers. Totally, 35 biomarkers were identified, including 31 by NMR and nine by MS (five by both). It turned out that curcumin treatment can partially recover the metabolism disorders induced by HFD, with the following metabolic pathways involved: TCA cycle, glycolysis and gluconeogenesis, synthesis of ketone bodies and cholesterol, ketogenesis of branched chain amino acid, choline metabolism, and fatty acid metabolism. Besides, NMR and MS based metabolomics proved to be powerful tools in investigating pharmacodynamics effect of natural products and underlying mechanisms.  相似文献   
93.
The development of novel targeted therapies holds promise for conquering chemotherapy resistance, which is one of the major hurdles in current breast cancer treatment. Previous studies indicate that mitochondria uncoupling protein 2 (UCP-2) is involved in the development of chemotherapy resistance in colon cancer and lung cancer cells. In the present study we found that lower level of miR133a is accompanied by increased expression of UCP-2 in Doxorubicin-resistant breast cancer cell cline MCF-7/Dox as compared with its parental cell line MCF-7. We postulated that miR133a might play a functional role in the development of Doxorubicin-resistant in breast cancer cells. In this study we showed that: 1) exogenous expression of miR133a in MCF-7/Dox cells can sensitize their reaction to the treatment of Doxorubicin, which is coincided with reduced expression of UCP-2; 2) knockdown of UCP-2 in MCF-7/Dox cells can also sensitize their reaction to the treatment of Doxorubicin; 3) intratumoral delivering of miR133a can restore Doxorubicin treatment response in Doxorubicin-resistant xenografts in vivo, which is concomitant with the decreased expression of UCP-2. These findings provided direct evidences that the miR133a/UCP-2 axis might play an essential role in the development of Doxorubicin-resistance in breast cancer cells, suggesting that the miR133a/UCP-2 signaling cohort could be served as a novel therapeutic target for the treatment of chemotherapy resistant in breast cancer.  相似文献   
94.
高光谱技术——生态学领域研究的新方法   总被引:1,自引:0,他引:1       下载免费PDF全文
高光谱技术是一种新的地物探测技术,该技术以其敏锐的地物光谱特征探测能力为精准识别地物属性提供了强有力的手段,在生态系统过程与属性研究中具有广阔的应用前景。该文以可见光-近红外光谱分析技术为例概述了高光谱技术的原理、特点与优势,以及高光谱技术分析的流程;总结并归纳了其在土壤、植物生理、农产品品质检测、凋落物分解方面的研究应用,指出高光谱技术与遥感成像技术结合在生态监测研究中的优势;归纳了高光谱技术应用中面临的问题,并希望高光谱技术在生态学领域研究中得到更广泛的应用。  相似文献   
95.
以13种栎属(Quercus Linn.)植物〔包括产自辽宁省的槲栎组(Sect. Quercus)8种和麻栎组(Sect. Aegilops)2种以及引自北美洲的沼生栎组(Sect. Erythobalanus)2种和引自波兰的白栎组(Sect. Lepidabalanus)1种〕为试材,观察了这些种类叶片的气孔形态,并分析了气孔器和气孔的形态参数,还对各形态参数间的相关性进行了分析;在此基础上,对13种栎属植物进行了聚类分析。结果表明:栎属植物叶片的气孔仅分布于下表皮;气孔器排列属无规则型;气孔保卫细胞呈肾形,内壁加厚;气孔下陷,呈椭圆形或狭长椭圆形。供试种类的气孔和气孔器的形态参数差异明显,变异系数差异较大;气孔器的长轴长度、短轴长度和面积分别为18.24~27.46μm、14.63~23.18μm和221.56~501.70μm2,变异系数分别为7.73%~15.90%、7.10%~17.44%和14.13%~32.73%,气孔器指数为0.73~0.85;气孔的长轴长度、短轴长度、面积和密度分别为8.69~15.41μm、1.94~8.49μm、15.15~104.93μm2和462.32~984.44 mm-2,变异系数分别为12.03%~22.17%、13.65%~34.10%、27.95%~54.13%和8.10%~16.99%,气孔指数为0.22~0.57;总体上,按照多数气孔器和气孔参数从大至小的变化趋势依次排序为沼生栎组、白栎组、麻栎组、槲栎组。相关性分析结果表明:供试种类的气孔密度与气孔器和气孔的长轴及短轴长度均呈极显著(P<0.01)负相关;气孔器面积与气孔器指数和气孔指数分别呈极显著和显著(P<0.05)正相关;气孔面积与气孔器和气孔的长轴和短轴长度、气孔器指数和气孔指数呈极显著正相关,但与气孔密度呈显著负相关。聚类分析结果表明:在欧氏距离10处可将13种栎属植物分为3类,第Ⅰ类包含槲栎组的8种,第Ⅱ类包含麻栎组和白栎组的3种,第Ⅲ类包含沼生栎组的2种。研究结果显示:栎属植物叶片的气孔特征具有一定的稳定性,可作为栎属植物组间分类及亲缘关系分析的依据之一。  相似文献   
96.
四川省小麦条锈菌群体遗传多样性的SSR分析   总被引:1,自引:0,他引:1  
利用TP-M13-SSR自动荧光检测技术,对四川省小麦条锈菌群体遗传多样性水平进行了分析。研究结果表明,四川省小麦条锈菌群体遗传多样性比较丰富,地区之间存在明显的差异,川西北和四川盆地的种群遗传多样性相对较高,而四川西南部和四川东南部的种群遗传多样性较低。四川小麦条锈菌群体存在一定的遗传分化,地区间的遗传变异仅占14.92%,群体间的遗传变异占总变异的23.06%,群体内遗传变异占60.02%,遗传变异主要存在于群体内部。基因流和共享基因型从分子水平证实了四川小麦条锈菌在地区间的传播,且川西北和四川盆地之间的菌源交流最为广泛。  相似文献   
97.
循环肿瘤细胞(CTCs)是导致肿瘤转移的主要原因,它在外周血中的含量与乳腺癌的转移、治疗和预后有密切的关系.本文对于CTCs的概念、检测方法、以及作为肿瘤转移预测指标的优势进行了综述.并对其在临床上的运用前景进行了展望.  相似文献   
98.
MTHFR基因C677T多态性与内蒙古汉族人群中冠心病的关系   总被引:1,自引:0,他引:1  
目的:检测中国内蒙古汉族人群中MTHFR基因多态性与冠心病的关系.方法:研究组包括62例冠心病(coronary heartdisease,CHD)患者和120例正常对照人群,用聚合酶链反应-限制性片段长度多态性技术(PCR-RFLP)分析C677T型突变.结果:677T/T基因型在冠心病人群中更普遍,是正常人群的3.4倍.结论:在内蒙古汉族人群中,677T/T基因型增加了个体患冠心痛的风险性.  相似文献   
99.
目的:构建Cpn0308基因真核表达重组质粒,为肺炎衣原体(Chlamydia pneumoniae,Cpn)核酸疫苗的研制做准备。方法:用PCR技术从Cpn AR39株基因组DNA中扩增Cpn 0308基因,经双酶切、连接等反应,重组入pcDNA3.1/HisA真核表达载体,转化到感受态细胞,再经含氨苄青霉素的LB培养基筛选,酶切、PCR扩增及测序鉴定。结果:从Cpn AR39株基因组DNA中扩增出特异的Cpn 0308基因,约400bp;酶切、重组、转化、筛选鉴定出pcDNA3.1/HisA-Cpn0308重组质粒;序列测定证实与GenBank登录的肺炎衣原体Cpn AR39株Cpn0308基因一致。结论:功地构建了pcDNA3.1/HisA-Cpn0308重组质粒,为肺炎衣原体核酸疫苗的研制奠定了基础。  相似文献   
100.
山茱萸不同栽培品种的 rDNA ITS 序列分析   总被引:1,自引:0,他引:1  
为测定山茱萸(Cornus officinalis Sieb.et.Zucc.)核糖体DNA的ITS序列,对山茱萸不同栽培品种进行了ITS序列分析。通过实验筛选出一对引物,进行PCR扩增,对扩增产物提取纯化,双脱氧链终止法DNA测序。然后,利用DNAssist Version 2.0软件加手工校正确定ITS1-5.8S-ITS2序列,并进行ITS序列分析。获得了山茱萸的ITS1-5.8S-ITS2完全序列,ITS1为253bp,5.8S为156bp,ITS2为273bp,总共682bp。7种果型的山茱萸其5.8S基因序列显示高度的一致性,圆柱形果型、长梨形果型、椭圆形果型和纺锤形果型的ITS区序列完全一致,短圆柱形果型在ITS1区3′端及ITS2区5′端各有1个变异位点;短梨形果型在ITS1区5′端有3个变异位点;长圆柱形果型在ITS1区有5个变异位点。结果表明,ITS序列在山茱萸种内比较保守,有的栽培品种之间有较小的差异,此研究为中药山茱萸分子鉴定提供了科学依据。  相似文献   
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