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991.
992.
Hang Wu 《人类与生态风险评估》2018,24(7):1952-1968
As landslides caused multiple casualties and destructions on a global scale, various models were applied to landslide susceptibility evaluation. In this study, a probability statistic model called the certain factor was adopted to assess the landslide susceptibility of Danba, a county in southwestern China, where the landslide events occur frequently but were poorly understood in regional landslide susceptibility. With the validation of area under the prediction rate curve, the resulting susceptibility map has the accuracies of 0.8211 and 0.8288 in experiment area and verification area, respectively. The validated assessment result was further processed to identify landslide-prone areas with the aid of the spatial clustering analysis of geographic information system. Two clustering indexes including Moran's I statistic and local indicator of spatial association (LISA) were involved. The Moran's I index of 0.959 and the LISA identification result accordant with previous investigations proved that the proposed method was rational and efficient to find the landslide-prone regions and make relevant decisions. 相似文献
993.
Dan-Jiao Wang Zhuang Hou Hang Xu Ran An Xin Su Chun Guo 《Bioorganic & medicinal chemistry letters》2018,28(22):3574-3578
A series of 4-chloro-2H-thiochromenes featuring nitrogen-containing side chains were designed, synthesized and tested in vitro for their antifungal activities. The results of preliminary antifungal tests showed that most target compounds exhibited good inhibitory activities against Candida albicans, Cryptococcus neoformans, Candida tropicalis. Notably, compounds 10e and 10y showed most potent activity in vitro against a variety of fungal pathogens with low MICs. Meanwhile, low cytotoxicity on mammalian cells has been observed for compounds 10e and 10y in the tested concentrations by the MTT assay. Therefore, the 4-chloro-2H-thiochromenes with nitrogen-containing groups provide new lead structures in the search for novel antifungal agents. 相似文献
994.
Genetic diversity of the Chinese goat in the littoral zone of the Yangtze River as assessed by microsatellite and mtDNA 下载免费PDF全文
Yue‐Hui Ma Ming‐Xing Chu Xiang‐Long Li Qiong‐Hua Hong Lan‐Hui Li Ji‐Jun Guo Lan Zhu Yan‐Guo Han Hui‐Jiang Gao Jia‐Hua Zhang Huai‐Zhi Jiang Cao‐De Jiang Gao‐Fu Wang Hang‐Xing Ren Mei‐Lan Jin Yuan‐Zhi Sun Peng Zhou Yong‐Fu Huang 《Ecology and evolution》2018,8(10):5111-5123
The objective of this study was to assess the genetic diversity and population structure of goats in the Yangtze River region using microsatellite and mtDNA to better understand the current status of those goat genetic diversity and the effects of natural landscape in fashion of domestic animal genetic diversity. The genetic variability of 16 goat populations in the littoral zone of the Yangtze River was estimated using 21 autosomal microsatellites, which revealed high diversity and genetic population clustering with a dispersed geographical distribution. A phylogenetic analysis of the mitochondrial D‐loop region (482 bp) was conducted in 494 goats from the Yangtze River region. In total, 117 SNPs were reconstructed, and 173 haplotypes were identified, 94.5% of which belonged to lineages A and B. Lineages C, D, and G had lower frequencies (5.2%), and lineage F haplotypes were undetected. Several high‐frequency haplotypes were shared by different ecogeographically distributed populations, and the close phylogenetic relationships among certain low‐frequency haplotypes indicated the historical exchange of genetic material among these populations. In particular, the lineage G haplotype suggests that some west Asian goat genetic material may have been transferred to China via Muslim migration. 相似文献
995.
Enzymatic esterification of sugars and fatty acids in tertiary butyl alcohol with lipase from Byssochlamys fulva NTG 9 was studied. Of different fatty acids examined, linoleic acid yielded the highest percentage of esterification of sugar (65.5%). Fructose gave a much higher percentage of esterification of fatty acid (71.3%) than glucose (47.8%), lactose (0%), maltose (67%) and sucrose (36.6%). 相似文献
996.
16种伞形科药用植物对超氧自由基的清除作用 总被引:11,自引:4,他引:7
采用Na2S2O4NaOHLuminol发光体系,应用智能化学发光法对16种伞形科药用植物提取物的自由基清除能力和对酪氨酸酶的抑制能力进行筛选。实验结果表明这些伞形科药用植物大都具有清除自由基的作用,其中羌活(NotopterygiumforbesideBois.)的“SOD样作用”达到2967U/mg(原生药量),提示这些植物具有稳定的非酶类清除自由基物质,并且“SOD样作用”强弱与其对酪氨酸酶的抑制能力呈明显正相关。 相似文献
997.
998.
Kluyveromyces marxianus NRRL Y-1196 produced the highest inulinase activity (38 U/mg protein) of six yeasts examined after 24 h growth in sauerkraut brine in shaking flasks at 30°C with 0.3% inulin as an enzyme inducer. The enzyme was recovered by acetone fractionation, with a yield of 81%. It had maximum activity at pH 4.4 and 55°C with K
m values for inulin and sucrose of 3.92 mm and 11.9 mm, respectively. The yeast raised the pH from 3.4 to above 7.0, using all the lactic acid in the brine. Growth of K. marxianus in sauerkraut brine with a small amount of inulin may usefully decrease the BOD and concomitantly produce inulinase.The authors are with the Department of Food Science and Technology, Cornell University, Geneva, New York 14456, USA 相似文献
999.
汉坦病毒抗原性差异及其基因分型 总被引:9,自引:0,他引:9
用抗汉坦病毒单克隆抗体(Mc-Ab)对汉坦病毒B78株(来自病人血)和R178株(分离自褐家鼠)进行间接免疫荧光试验,以分析病毒的单克隆抗体反应谱,又用病毒免疫血清进行交叉中和试验,结果表明,两株病毒均具有双型(Ⅰ型/HTN型和Ⅱ型/SEO型)反应特征,但R178株基本上属于Ⅰ型。用汉坦病毒Ⅰ ̄Ⅳ型型特异性引物进行PCR扩增,B78株用Ⅰ型和Ⅱ型引物均得到特异性扩增,而R178株虽经重复扩增均未见 相似文献
1000.
Ultrastructural localization of glutamic oxalacetic transaminase activity in cardiac muscle fiber and cardiac mitochondrial fraction of the rat 总被引:1,自引:0,他引:1
Sin Hang Lee 《Histochemistry and cell biology》1969,19(2):99-109
Summary The ventricular heart muscle of the rat was fixed in glutaraldehyde-formaldehyde mixture. The tissue blocks were incubated in a medium containing 20 mM 1-aspartic acid, 2 mM -ketoglutaric acid and 6 mM lead nitrate as major ingredients. The enzymatic reaction product due to glutamic oxalacetic transaminase (GOT) activity was found to be localized in the cristae and at the surface of the mitochondria, in the cisternae of the nuclear envelope and in the sarcoplasmic reticulum. Isolation of the mitochondrial fraction from the homogenate of the fixed heart muscle was performed, and GOT activity in this fraction was demonstrated both histochemically and biochemically.This Work was Supported by a Research Grant from the Medical Research Council of Canada (MA-3340). 相似文献