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61.
Mei flower is one of the most famous ornamental flowers in eastern Asia for its blossoming in early spring. Amplified fragment length polymorphism (AFLP) is one of the most frequently used techniques for analysis of genetic variation and is used herein for the first time inPrunus mume. This research provides a detailed and modified AFLP protocol for Mei genomic DNA digested withEcoRI/PstI restriction endonuclease combinations. The 10 best primer pairs of high polymorphism were screened from 256 primer combinations that could reliably and repetitively distinguish 14 Mei samples and would be suitable for genetic analysis of more cultivars. Ten primer pairs produced up to a total of 524 AFLP bands and up to 233 polymorphic bands. The ratio of polymorphic bands scoped from 35.71% to 59.67%, and the average ratio was 44.46% in the 10 primers. AFLP is an effective, inexpensive, and timesaving technique for the genetic differentiation of the Mei cultivars, as evidenced in this study.  相似文献   
62.
目的观察紫草油对肛瘘术后临床疗效改善情况以及血清中TGF-β1、Smad3的含量变化。方法将我院收治的肛瘘术后患者90例采用简单随机法分为紫草油组、凡士林组和肤痔清组各30例,术后第1天至创面愈合,每天分别给予紫草油、凡士林、肤痔清软膏外用,并于术后第1、7、14、21天观察创面疼痛、水肿、出血情况,以及酶联免疫吸附法(ELISA法)检测患者血清中TGF-β1和Smad3含量。结果 3组患者治疗后均能缓解术后水肿、疼痛、出血症状;紫草油组在治疗后第21天与肤痔清组、凡士林组比较,水肿、疼痛、出血的积分差异显著(P0.05)。治疗后第7、14、21天紫草油组与肤痔清组、凡士林组的TGF-β1含量比较,差异具有统计学意义(P0.05);治疗后组内血清Smad3含量均较治疗前明显降低,差异有统计学意义(P0.05),但治疗后第21天紫草油组与肤痔清组、凡士林组的Smad3含量比较,差异无统计学意义(P0.05)。结论紫草油能明显缓解肛瘘术后创面水肿、疼痛、出血情况,且疗效优于肤痔清及凡士林,能有效提高TGF-β1含量及降低血清Smad3含量,促进创面愈合。  相似文献   
63.
Chen H  Xu N  Zhou Y  Qiao L  Cao J  Yao Y  Hua H  Pei Y 《Steroids》2008,73(6):629-636
Seven new steroidal glycosides (amplexicosides A (4), B (7), C (8), D (9), E (10), F (11), and G (12)), along with six known compounds (cynatratoside A (1), tylophoside A (2), cynatratoside B (3), glaucogenin A (5), glaucoside A (6), and hancoside A (13)) were isolated from the 95% ethanol extract of the roots of Cynanchum amplexicaule (Sieb. et Zucc.). Their structures were determined based on spectral and chemical evidence. Compound 12 has a 14, 15-secopregnane-type skeleton aglycone, which has not been reported in literature.  相似文献   
64.
以盐生植物海滨木槿为材料,不同浓度NaCl胁迫对其抗氧化酶活性、抗氧化物质和渗透调节物质含量的影响进行分析.结果显示随着NaCl浓度的升高,海滨木槿叶片中超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化物酶(POD)、谷胱甘肽还原酶(GR)和谷胱甘肽转硫酶(GST)的活性先升高后降低,而过氧化氢酶(CAT)的活性呈持续下降趋势,但它们达到最高活性时的NaCl浓度不同;各处理的丙二醛(MDA)含量先下降后升高,但始终低于对照;抗氧化物质抗坏血酸(AsA)和谷胱甘肽(GSH)的含量均高于对照,且在200 mmol·L-1时达到最高;各处理渗透调节物质可溶性糖和脯氨酸(Pro)的含量均较对照增加且升幅较大.研究表明,海滨木槿在NaCl胁迫下具有较强的活性氧清除能力和渗透调节能力,从而表现出较强的耐盐性.  相似文献   
65.
An analysis is presented of three possible pathways of reproductive allocation, namely, allocation of resources to reproductive organs from reproductive shoots, from non-reproductive shoots and from the main trunk. These pathways were examined by comparing the amount of storage starch in reproductive shoots, non-reproductive shoots and the main trunk in Styrax obassia, a typical masting tree species, during a year of little flowering (1999) and in a mass-flowering year (2000). In addition, we measured rates of light-saturated photosynthesis in leaves of reproductive and non-reproductive shoots to examine the contribution of photosynthetic production to reproductive costs. In both the main trunk and non-reproductive shoots the pattern of seasonal variation in the amount of starch did not differ between 1999 and 2000. However, in the mass-flowering year, the amount of starch in the reproductive shoots was less than that in non-reproductive shoots during the growing season. Thus, reproductive shoots bore most of the cost of reproduction, although non-reproductive shoots and the main trunk also bore some of the cost. Mass-based rates of light-saturated photosynthesis of the leaves of reproductive shoots were significantly higher than those of non-reproductive shoots during both the flowering and the fruiting period. However, leaves of reproductive shoots had a significantly smaller area, a lower mass per area, and lower concentrations of nitrogen than leaves of non-reproductive shoots, although the number of leaves did not differ between the two types of shoots. Therefore, the amount of photosynthate per shoot was significantly lower in reproductive shoots than in non-reproductive shoots. These results suggest that the cost of reproduction depends predominantly on storage starch in reproductive shoots, although it is still unclear how much photosynthate is allocated to reproductive organs from non-reproductive shoots.  相似文献   
66.
紫草提取物的体外抗氧化活性研究   总被引:5,自引:0,他引:5  
为研究紫草色素(LEP)的体外抗氧化活性,采用常规回流方法提取LEP,测定了LEP对超氧自由基(O2)和1,1-二苯基-2-苦苯肼自由基(DPPH.)的清除能力,及其对β-胡萝卜素/亚油酸自氧化体系的抑制作用。结果表明,LEP对DPPH.和O2均有较强的清除能力,并且对β-胡萝卜素/亚油酸自氧化体系有明显的抑制作用,说明紫草的药理作用可能与LEP较强的抗氧化能力有关。  相似文献   
67.
采用HPLC法,以白藜芦醇、白藜芦醇甙及大黄素的含量为指标,对虎杖中的有效成分进行了综合提取,通过正交实验,确定出乙醇溶剂提取的最佳工艺为:以80%的乙醇水溶液为提取剂,液固比为12:1,在70℃下提取2次,每次提取2h,HPLC法测定结果表明,从虎杖中提取的有效成分的含量分别可达:白藜芦醇为2.40mg/g,白藜芦醇甙为18.12mg/g,大黄素为16.82m/g。  相似文献   
68.
The SOD isoenzymes of different soybeans were studied in this experiment and the results showed that: 1. there were 7 SOD isoenzyme bands in all soybean genotypes used in this experiment, 2. the SOD activity (unit/g fr. wt.) in different soybean seeds decreased as the evolutionary process advanced, 3 the SOD activity decreased as the wt./100 seeds increased, and the color of seed coat changed from black to yellow. The relationship between SOD activity and the evolutionary process was discussed.  相似文献   
69.
在标本(包括许多模式标本)查考和居群调研的基础上,对刚竹属Phyllostachys Sieb.et Zucc.一些类群的分类问题进行了评注,其中将遂昌雷竹Ph.primotina Wen作为不同于红壳雷竹Ph.incarnata Wen的1个独立的竹种看待;8个拉丁学名被减为异名;Ph.heteroclada Oliv.f.solida(S.L.Chen)C.P.Wang et Z.H.Yu因其  相似文献   
70.
We investigated the effects of a topically applied extract of the heartwood of Broussonetia kazinoki Sieb (B. kazinoki) on atopic dermatitis (AD)-like skin lesions induced by an extract of the house-dust mite Dermatophagoides farina in NC/Nga mice. We found that topically applied B. kazinoki extract suppressed the histological manifestations of AD-like skin lesions, and decreased the levels of plasma immunoglobulin E (IgE) and interleukin-4 (IL-4) in the mice. Moreover, B. kazinoki inhibited the induction of thymus-and-activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22), and regulated-on-activation-normal T cell-expressed-and-secreted chemokine (RANTES/CCL5) in HaCaT cells activated by tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In conclusion, our results suggest that B. kazinoki extract has therapeutic advantages in the treatment of AD.  相似文献   
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