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21.
溪黄草化学成分的研究 总被引：1，自引：0，他引：1
溪黄草Plophentholdes(唇形科)全草的乙醇提取物中,分离出三种结晶化合物,经元素分析、红外光谱、核磁共振谱、质谱的测定,确定三种结晶化合物的结构。 相似文献
22.
肌动蛋白（actin）在维持细胞结构、细胞运动和细胞分裂等过程中发挥着重要的作用.为了克隆鳡（Elopichthys bambusa）β-肌动蛋白（β-actin）全长cDNA,采用反转录PCR（RT-PCR）和cDNA末端快速扩增（rapid amplification of cDNA ends,RACE）技术,从鳡肌肉获得全长为1775bp的β-actin cDNA序列,其中包含1128bp的开放性阅读框,编码375个氨基酸,5′-非翻译（UTR）区为98个核苷酸,3′-UTR区为549个核苷酸.核苷酸与氨基酸的同源性分析发现,鳡β-actin与鲤形目类硬骨鱼的同源性均在98%以上,其中与团头鲂（Megalobrama amblycephala）的同源性最高,分别为98.94%和99.73%,而与其他脊椎类动物如哺乳类、鸟类、两栖类的同源性也分别在85%和97%以上,说明该基因在生物的分子进化过程中具有很高的保守性.采用核苷酸系统发育分析结果显示鳡β-actin与鲤形目类硬骨鱼聚类在一起,且与团头鲂的亲缘关系最近.RT-PCR分析结果显示,β-actin基因在鳡的肝脏、肾、肠、脑、心脏、鳃和肌肉等7个组织均有表达. 相似文献
23.
胰岛素抵抗是运动科学研究领域的热点,对于胰岛素抵抗评价方法的选择对该类型研究的质量有着重要影响.胰岛素抵抗评价方法种类较多,可以根据研究类型、研究对象数量和指标检测方法等因素做出选择.稳态模型（HOMA）评估模式即是众多胰岛素抵抗评价方法的一种,是以基础水平的葡萄糖、胰岛素或C肽为参考,并以胰岛素抵抗指数的形式（HOMA-IR）对β细胞功能和胰岛素抵抗进行评价.本文从稳态模型评估模式的应用入手,对中文运动科学论文使用该模型的情况进行研究,分析该模型使用中出现的各种问题,以期为正确使用该模型提供参考和借鉴. 相似文献
24.
The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine. 相似文献
25.
利用比较原理和积分均值等方法,在污染环境容量较小的条件下,讨论了体内毒素浓度相同,具有食物链影响的二维Volterra互惠系统的生存状况,得到了种群β-生存和β-灭绝的充分条件． 相似文献
26.
研究形如F=α＋∈β＋2kβ2/α-k2β4/3α3的（α,β）型Finsler度量的性质,给出此度量为Douglas度量的一个充分必要条件,其中α：=√αij（x）yiyj是黎曼度量,β：=bi（x）y是1-形式,∈和k≠0都是常数. 相似文献
27.
D. Vitucci E. Imperlini R. Arcone A. Alfieri A. Canciello L. Russomando 《Journal of sports sciences》2018,36(14):1630-1639
Myogenesis is the formation of muscle tissue from muscle precursor cells. Physical exercise induces satellite cell activation in muscle. Currently, C2C12 murine myoblast cells are used to study myogenic differentiation. Herein, we evaluated whether human LHCN-M2 myoblasts can differentiate into mature myotubes and express early (myotube formation, creatine kinase activity and myogenin) and late (MyHC-β) muscle-specific markers when cultured in differentiation medium (DM) for 2, 4 and 7 days. We demonstrate that treatment of LHCN-M2 cells with DM supplemented with 0.5% serum from long-term (3 years) differently exercised subjects for 4 days induced myotube formation and significantly increased the early (creatine kinase activity and myogenin) and late (MyHC-β expression) differentiation markers versus cells treated with serum from untrained subjects. Interestingly, serum from aerobic exercised subjects (swimming) had a greater positive effect on late-differentiation marker (MyHC-β) expression than serum from anaerobic (body building) or from mixed exercised (soccer and volleyball) subjects. Moreover, p62and anti-apoptotic Bcl-2 protein expression was lower in LHCN-M2 cells cultured with human sera from differently exercised subjectst han in cells cultured with DM. In conclusion, LHCN-M2 human myoblasts represent a species-specific system with which to study human myogenic differentiation induced by serum from differently exercised subjects. 相似文献
28.
目的:探究二甲双胍联合抗阻运动干预对糖尿病大鼠的血糖的影响,以及对下丘脑TGF-β1、Smad2/3含量的影响。方法:采用高糖高脂饲料喂养结合腹腔注射链脲佐菌素(Streptozocin,STZ)注射液诱导糖尿病大鼠模型,二甲双胍和抗阻爬梯干预,Western-Blot法检测糖尿病大鼠下丘脑TGF-β1、Smad2/3蛋白表达量。结果:二甲双胍和运动均有一定降血糖效果,以药物治疗最为明显,联合干预的效果低于单独干预;二甲双胍和抗阻运动干预及其联合干预,Smad2/3、TGF-β1表达无明显的改变。结论:6周的糖尿病进程可能没有损伤大鼠下丘脑,抗阻运动和二甲双胍药物干预降低糖尿病大鼠血糖可能存在一定的抵消作用。 相似文献
29.
β-榄香烯立体结构的分子力学研究 总被引：1，自引：0，他引：1
利用分子力学计算方法研究了β-榄香烯的构型和构象．通过能量最小化,对所有构象空间进行烯基取代基旋转势能极小点的全面搜索,确定了β-榄香烯的优势空间构象;并且与β-榄香烯衍生物的单晶X-射线衍射结构测定的有关结果做了比较和讨论 相似文献
30.
辛冬梅 《广东教育学院学报》2008,28(5):26-30
引入两个独立参数λ,α和两对共轭指数（p,q）,（r,s）,建立了一个具有多参数的逆向Hilbert型积分不等式,此不等式联系着两个基本Hilbert型积分不等式,另外还证明常数因子为最佳值．作为应用,建立了它的等价式并考虑了一些特殊结果． 相似文献