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91.
以间二酚和氰基乙酸为主要原料,经Pechmann反应、水解、乙醚化、Williamson反应合成了9种7-烷氧基-4-乙氧基香豆素类新化合物.Williamson反应的优化条件为:N,N-二甲基甲酰胺(DMF) 为溶剂,n(4-乙氧基-7-羟基香豆素) :n(卤代烃) :n(碳酸钾) :n(TBAB,四正丁基溴化铵) =1:1.5:2.5:0.1,60~80℃反应11~25 h,产率为72%~95%.中间产物及目标产物结构经红外光谱(IR) 、质谱(MS) 、核磁共振氢谱(1H NMR) 表征得以证实. 相似文献
92.
大豆蛋白质有关性状的QTL定位 总被引:2,自引:1,他引:1
以科丰1号×南农1138-2组合衍生的184个重组自交家系(简称RIKY)和(Essex×ZDD2315)×ZDD2315衍生的114个BC1F2家系(简称BIEX)为材料,对蛋白质含量、蛋油总量与油脂含量,11S、7S、11S/7S,11S-1~11S-4, 7S-1~7S-6等4组16个性状利用WinQTL Cartographer Ver.2.5的复合区间作图法(CIM)、多区间作图法(MIM)和IciMapping Ver.2.0的完备区间作图法(ICIM)进行QTL分析, 结果表明:(1) 在RIKY和BIEX群体分别定位到17+个和21+个QTL,合计38+个QTL;在RIKY有蛋白、油脂、蛋油总量QTL11个,在11S和7S亚基组上分别只有1+和3+个;在BIEX有前性状QTL2+个,有后性状QTL分别9+和6+个;(2) 两群体16个性状上均没有检测到共享的QTL,说明两群体的蛋白质有关性状具有完全不同的遗传基础;RIKY的两个亲本间蛋白、油脂和蛋油总量有明显遗传差异,但在亚基组上遗传差异不大,而BIEX则反之;(3) 4组总、分性状中,两群体一致表现出蛋白、油脂和蛋油总量和11S、7S和11S/7S比值两组在总、分性状间共享QTL(共同遗传基础), 而11S亚基组和7S亚基组两组性状在总、分性状间无共享的QTL;(4) 蛋白质有关性状QTL定位结果和分离分析结果共同表明这类性状主效基因和微效基因均占较大比重,要考虑两者兼用的育种方法。 相似文献
93.
In water-efficient rice production, grain yield is often constrained by panicle size. The objective of this study was to genetically dissect the response of panicle morphology to irrigation regimes in aerobic rice culture. We grew ‘Akihikari’ (a lowland japonica cultivar) × ‘IRAT109’ (an upland japonica cultivar) backcross inbred lines in aerobic soils with full or limited irrigation for 2 years, and examined 4 panicle traits—number of florets per panicle (FPP), number of primary branches per panicle (BPP), number of florets per primary branch (FPB), and frequency of pre-flowering floret abortion (%FA)—and grain yield. QTLs for BPP were detected in both the irrigation regimes but QTLs for FPB and %FA were detected mostly only in either of the irrigation regimes. The QTL for FPP on chromosome 2 (RM3421–RM213) coincided with that for yield under full irrigation, showing that this QTL is related to sink capacity and yield potential in aerobic rice culture. On the other hand, the QTL for FPB on chromosome 1 (RM3148–RM243) coincided with that for yield under limited irrigation, when water deficit was moderate. The QTL for root axis length at vegetative stage, previously identified in the same mapping population, was located near this region. This study unravelled the complicated genetic control on panicle morphology in aerobic rice culture, and suggested the positive roles of the dehydration avoidance mechanism by vigorous root growth on panicle size and yield under dry soil conditions. 相似文献
94.
95.
Development of broad‐spectrum bacterial blight resistance into thermo‐sensitive genic male sterile lines 下载免费PDF全文
Two‐line hybrid rice technology is an effective way to increase rice production and improve rice quality. In this study, three bacterial blight (BB) resistance genes, Xa7, Xa21 and Xa23, were introgressed separately into C815S, a popular thermo‐sensitive genic male sterile (TGMS) line to develop five BB‐resistant lines (Hua1005S, Hua1002S, Hua1009S, Hua1006S and Hua1001S) to be resistant against seven races of Xanthomonas oryzae pv. oryzae (Xoo). The two‐line hybrids with heterozygous Xa23 were resistant against seven Xoo strains. But, the hybrids with heterozygous loci for both Xa7 and Xa21 were only resistant against three Xoo strains and were moderately susceptible to the other four strains indicating the role of modifiers influencing the poor expression of dominant BB resistance genes under heterozygous state. Among them, Hua1006S was found to be a promising TGMS line with its higher degree of disease resistance level on account of broad‐spectrum resistance gene Xa23 besides possessing better plant type and rice grain quality features. 相似文献
96.
Wen-Liang Chen Ekaterina Turlova Christopher L. F. Sun Ji-Sun Kim Sammen Huang Xiao Zhong Yong-Yuan Guan Guan-Lei Wang James T. Rutka Zhong-Ping Feng Hong-Shuo Sun 《Marine drugs》2015,13(4):2505-2525
Glioblastoma, the most common and aggressive type of brain tumors, has devastatingly proliferative and invasive characteristics. The need for finding a novel and specific drug target is urgent as the current approaches have limited therapeutic effects in treating glioblastoma. Xyloketal B is a marine compound obtained from mangrove fungus Xylaria sp. (No. 2508) from the South China Sea, and has displayed antioxidant activity and protective effects on endothelial and neuronal oxidative injuries. In this study, we used a glioblastoma U251 cell line to (1) explore the effects of xyloketal B on cell viability, proliferation, and migration; and (2) investigate the underlying molecular mechanisms and signaling pathways. MTT assay, colony formation, wound healing, western blot, and patch clamp techniques were employed. We found that xyloketal B reduced cell viability, proliferation, and migration of U251 cells. In addition, xyloketal B decreased p-Akt and p-ERK1/2 protein expressions. Furthermore, xyloketal B blocked TRPM7 currents in HEK-293 cells overexpressing TRPM7. These effects were confirmed by using a TRPM7 inhibitor, carvacrol, in a parallel experiment. Our findings indicate that TRPM7-regulated PI3K/Akt and MEK/ERK signaling is involved in anti-proliferation and migration effects of xyloketal B on U251 cells, providing in vitro evidence for the marine compound xyloketal B to be a potential drug for treating glioblastoma. 相似文献
97.
98.
高端技术技能人才贯通培养实验项目(简称贯通培养项目)是北京市为更好地适应国际化产业发展,培养高素质技能型人才所推行的新型教学模式,涵盖了高中教育、职业教育、本科教育阶段。通过对基础文化课阶段的教学质量现状进行调查分析发现,这一项目在人才培养方案、课程体系、教学督导、师资队伍等方面获得一定经验,也存在一定问题。要提高基础文化课阶段的教学质量,需要在上述四个方面进一步改进。 相似文献
99.
利用收集验证完善得到的PPI协议实现了上位机对PLC的监控,将西门子S7—200PLC与各个控制节点相连,上位机通过控制PLC来实现自动和手动控制各个节点,以实现节能型日光温室温度监控系统的自动化。 相似文献
100.
苏云金芽胞杆菌(Bacillus thuringiensis)杀虫晶体蛋白Cry7Ba1需要在强碱性缓冲液中(pH12.5)才能溶解,而且只有溶解后才能对小菜蛾(Plutella xvlostella)表现出毒力,其LC50为1.33μg/mL。分别用Cry1Ac和Cry1C晶体蛋白的C-半段替换Cry7Ba1的C-半段,结果发现当Cry7Ba1的C-半段被替换后,重组晶体蛋白与Cry1Ac和Cry1C等其它晶体蛋白一样在弱碱性条件下(pH9.5)能有效溶解,而且重组晶体蛋白对小菜蛾的杀虫活性没有发生明显变化,其LC50分别为1.32和1.39μg/mL。结果还显示重组晶体蛋白不需要经过体外溶解就能对小菜蛾表现出杀虫活性。研究结果揭示Cry7Ba1晶体蛋白难溶的特性是由其C-半段结构决定的,通过改变其C-半段结构改善溶解性,为该晶体蛋白在害虫生物防治中的应用提供了可能。 相似文献