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31.
PCR analysis of dystrophin gene mutation and expression. 总被引:2,自引:0,他引:2
J S Chamberlain N J Farwell J R Chamberlain G A Cox C T Caskey 《Journal of cellular biochemistry》1991,46(3):255-259
32.
In situ studies of second-harmonic generation (SHG) in monolayers of pure hemicyanine dyes and their mixtures with arachidic acid at the air/water interface were performed. The studies revealed an unexpected chemical instability of the hemicyanine dyes involving a cleavage of the stilbene double bond when deposited onto the water surface. This reaction occurred especially rapidly in the presence of the arachidic acid. Dilution with arachidic acid did not lead to a significant enhancement of the harmonic intensity. 相似文献
33.
Both the high molecular weight and the low molecular weight variants of urinary Y-glutamyl transpeptidase, displayed transpeptidase
(pH optimum 8.6) and autotrans-peptidase (pH optimum 9.4) activities. Iodoacetamide inhibited the transpeptidase activity
more efficiently than the autotranspeptidase activity with respect to both variants of Y-glutamyl transpeptidase. The high
molecular weight form utilized L-glutamine as a better acceptor than L-cystine during the transpeptidation reaction whereas
the reverse was the case with the low molecular weight variant. While phenylmethylsulphonyl fluoride-treated enzymes retained
full activitiesper se, addition of maleic acid to the modified enzyme was found to inhibit the catalytic activities indicating a maleic acid-induced
conformational change of the modified enzyme. 相似文献
34.
Han Mo Linghan Wang Yuting Chen Xuchen Zhang Ning Huang Tingting Liu Wantong Hu Yi Zhong Qian Li 《Aging cell》2022,21(6)
Age‐related memory impairment (AMI) is a common phenomenon across species. Vulnerability to interfering stimuli has been proposed to be an important cause of AMI. However, the molecular mechanisms underlying this vulnerability‐related AMI remain unknown. Here we show that learning‐activated MAPK signals are gradually lost with age, leading to vulnerability‐related AMI in Drosophila. Young flies (2‐ or 3‐day‐old) exhibited a significant increase in phosphorylated MAPK levels within 15 min after learning, whereas aged flies (25‐day‐old) did not. Compared to 3‐day‐old flies, significant 1 h memory impairments were observed in 15‐, 20‐, and 30‐day‐old flies, but not in 10‐day‐old flies. However, with post‐learning interfering stimuli such as cooling or electric stimuli, 10‐day‐old flies had worse memory performance at 1 h than 3‐day‐old flies, showing a premature AMI phenomenon. Increasing learning‐activated MAPK signals through acute transgene expression in mushroom body (MB) neurons restored physiological trace of 1 h memory in a pair of MB output neurons in aged flies. Decreasing such signals in young flies mimicked the impairment of 1 h memory trace in aged flies. Restoring learning‐activated MAPK signals in MB neurons in aged flies significantly suppressed AMI even with interfering stimuli. Thus, our data suggest that age‐related loss of learning‐activated neuronal MAPK signals causes memory vulnerability to interfering stimuli, thereby leading to AMI. 相似文献
35.
Kathy Darragh Gabriela Montejo‐Kovacevich Krzysztof M. Kozak Colin R. Morrison Clarisse M. E. Figueiredo Jonathan S. Ready Camilo Salazar Mauricio Linares Kelsey J. R. P. Byers Richard M. Merrill W. Owen McMillan Stefan Schulz Chris D. Jiggins 《Ecology and evolution》2020,10(9):3895-3918
In many animals, mate choice is important for the maintenance of reproductive isolation between species. Traits important for mate choice and behavioral isolation are predicted to be under strong stabilizing selection within species; however, such traits can also exhibit variation at the population level driven by neutral and adaptive evolutionary processes. Here, we describe patterns of divergence among androconial and genital chemical profiles at inter‐ and intraspecific levels in mimetic Heliconius butterflies. Most variation in chemical bouquets was found between species, but there were also quantitative differences at the population level. We found a strong correlation between interspecific chemical and genetic divergence, but this correlation varied in intraspecific comparisons. We identified “indicator” compounds characteristic of particular species that included compounds already known to elicit a behavioral response, suggesting an approach for identification of candidate compounds for future behavioral studies in novel systems. Overall, the strong signal of species identity suggests a role for these compounds in species recognition, but with additional potentially neutral variation at the population level. 相似文献
36.
37.
地方认同视角下居民对农业文化遗产认知及保护态度——以福州茉莉花与茶文化系统为例 总被引:5,自引:0,他引:5
居民对农业文化遗产的认知态度影响其行为选择,并对农业文化遗产的保护及可持续发展具有重要意义。基于人文地理学及环境心理学领域的地方认同理论,选择历史认同、现实认同、情感认同及行为认同4个维度变量,通过问卷调查,以福州居民对全球重要农业文化遗产"福州茉莉花与茶文化系统"的认知及保护态度作为研究对象,并通过构建福州居民农业文化遗产认知及保护规律定量分析居民认知态度、保护行为与人口特征之间的关系。结果表明:(1)福州居民对茉莉花与茶文化系统的行为认同维度得分高于其他维度,且福州市民各维度得分均高于外来居民;(2)受访居民对农业文化遗产的地方认同与其年龄、受教育水平、收入水平及在福州居住时间长短的关系较为密切;(3)通过构建福州居民农业文化遗产认知及保护规律发现,福州居民对农业文化遗产的保护行为主要受其对该遗产项目认知态度的影响,与居民人口特征相关性较弱。拓展农业文化遗产领域的研究视角及方法,促进农业文化遗产地动态保护与可持续发展具有参考价值。 相似文献
38.
39.
Dieter Gross 《Phytochemistry》1975,14(10):2105-2112
40.
Gabrielle Thiébaut Guillaume Tixier François Guérold Serge Muller 《Hydrobiologia》2006,570(1):159-164
The aim of our study was to assess the water quality of the upper Moselle river by using biological indices. Simultaneous
physico-chemical surveys were also undertaken from May 1999 to April 2000. Twelve sampling sites were selected in order to
provide a wide range of potential pollution. Chemical analysis did not reveal any major problem of pollution. However a lower
water quality resulting from domestic pollution was established for some sampling sites. A biological monitoring combining
both macroinvertebrates and macrophytes was performed. Biological indices based on plant community structure and macrophyte
composition were not pertinent tools, whereas simple indices based on taxonomic richness of particular groups of macroinvertebrates
were strongly correlated with several chemical parameters, showing that such simple biological variables should represent
powerful indicators of ecosystem degradation. 相似文献