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排序方式: 共有299条查询结果,搜索用时 203 毫秒
71.
Yellow cypress (Chamaecyparis obtusa (Siebold & Zucc.) Endl. var. formosana (Hayata) Rehder) is the predominant tree species of Taiwan's nutrient-poor, mountain fog forests. Little is known about the potential contribution of solute uptake from fog to the overall nutrition of these trees. Shoots of yellow cypress seedlings were misted with artificial fog containing the tracer rubidium (Rb) in laboratory and field experiments to determine if there is solute uptake from the fog. After misting shoots for six weeks, substantial amounts of tracer were detected in unexposed roots by inductively coupled plasma mass spectroscopy bulk analysis. Possible routes of entry were examined by element imaging with energy dispersive X-ray analysis. Direct uptake of the tracer into leaves across the cuticle and epidermis was small, excluding this as the major uptake path. Accumulations of Rb were found on leaf surfaces along the edges of the leaves. The almost daily changes in fog coverage and air humidity may enhance the accumulation of fog solutes at leaf edges. Accumulation of Rb was also found in narrow clefts between opposite leaves and between the outermost and underlying alternating stacked leaves. The clefts provide a direct passage from the leaf surface to the space beneath the imbricate leaves and the underlying alternate leaves, possibly facilitating solute uptake from fog, which in turn may contribute to the nutrition of yellow cypress. 相似文献
72.
Dai Kusumoto Hayato Masuya Toshihide Hirao Hideaki Goto Keiko Hamaguchi Wen-I Chou Wiwat Suasa-ard Sawai Buranapanichpan Sopon Uraichuen Oraphan Kern-asa Sunisa Sanguansub Aumporn Panmongkol Thu Pham Quang Sih Kahono Heddy Julistiono Naoto Kamata 《Journal of Forest Research》2014,19(4):404-410
Japanese oak wilt (JOW) has been prevalent in Japan since the late 1980s. Infections of the fungus, Raffaelea quercivora Kubono et Shin. Ito, which is transmitted by an ambrosia beetle [Platypus quercivorus (Murayama)], can cause JOW. Although R. quercivora, P. quercivorus, and oak trees are distributed in other Asia–Pacific countries, the incidence of JOW has not been reported outside Japan. In this study, we collected R. quercivora isolates from 5 Asian countries, including Japan, and compared their ability to induce sapwood discoloration by inoculating Q. serrata logs. The tangential widths of the discoloration in sapwoods inoculated with non-Japanese isolates were equivalent to or greater than those of the 2 Japanese isolates. This indicates that a lack of JOW incidence outside Japan is not because of the lowered ability of R. quercivora to spread discoloration compared with the Japanese isolates. Statistical analyses of the relationship between discoloration and phylogeny based on DNA sequences of actin and chitin synthase showed that the discoloration width was independent of phylogenetic relatedness among the isolates. To discuss why the occurrence of JOW has not been reported outside Japan, further studies (e.g., on host susceptibility and P. quercivorus aggression) throughout Asia are needed. 相似文献
73.
Chien-Chung Cheng Chi-Yuan Chou Yao-Chin Chang Hsuan-Wen Wang Chi-Chung Wen Yau-Hung Chen 《Journal of toxicologic pathology》2014,27(2):115-121
In zebrafish, UV exposure leads to fin malformation phenotypes including fin reduction
or absence. The present study evaluated UV-protective activities of comfrey leaves
extracts in a zebrafish model by recording fin morphological changes. Chemopreventive
effects of comfrey leave extracts were evaluated using Kaplan-Meier analysis and Cox
proportional hazards regression. The results showed that (1) the mean times of return to
normal fin in the UV+comfrey (50 and 100 ppm) groups were 3.43 and 2.86 days and were
quicker compared with that in the UV only group (4.21 days); (2) zebrafish fins in the
UV+comfrey (50 and 100 ppm) groups were 2.05 and 3.25 times more likely to return to
normal than those in the UV only group; and (3) comfrey leave extracts had UV-absorbance
abilities and significantly reduced ROS production in UV-exposed zebrafish embryos, which
may attenuate UV-mediated apoptosis. In conclusion, comfrey leaves extracts may have the
potential to be developed as UV-protective agents to protect zebrafish embryos from
UV-induced damage. 相似文献
74.
Myxovirus-like structures in a case of human chronic polymyositis 总被引:11,自引:0,他引:11
S M Chou 《Science (New York, N.Y.)》1967,158(807):1453-1455
Intranuclear and intracytoplasmic aggregates of filaments with tubular structures and transverse striations occurred in muscle tissues biopsied from a patient with chronic polymyositis. The filamentous tubules bear a close resemblance to the incomplete form of myxovirus in which the envelope is missing. Three biopsies from the same patient, taken during a period of 1(1/2) years, all revealed these structures. This finding provides presumptive evidence that a chronic persistent viral infection may be involved in the pathogenesis of chronic polymyositis. 相似文献
75.
本文记述了蛾蜡蝉科Flatidae国内一新记录属和一新种,模式标本保存在西北农业大学昆虫博物馆 相似文献
76.
Germline organization of the murine T cell receptor beta-chain genes 总被引:11,自引:0,他引:11
H S Chou C A Nelson S A Godambe D D Chaplin D Y Loh 《Science (New York, N.Y.)》1987,238(4826):545-548
77.
Brain serotonin concentration: elevation following intraperitoneal administration of melatonin 总被引:5,自引:0,他引:5
The intraperitoneal administration of melatonin to rats caused an increase in brain serotonin concentration, especially in the midbrain. This effect could be demonstrated within 20 minutes of melatonin administration and was not associated with changes in norepinephrine concentration. 相似文献
78.
对在宁夏彭阳县引进的花椒品种大红袍、秦安1号、豆椒和油椒的生物学特性、成活率、生长量、抗逆性与结果情况的分析比较,结果表明,秦安1号与大红袍2个品种的综合指标优于其他品种,在彭阳县的适应性较好,在宁夏南部山区其他条件类似的地方也可以大力发展.而豆椒和油椒适于在庭院等栽种. 相似文献
79.
A whole-genome assembly of Drosophila 总被引:1,自引:0,他引:1
Myers EW Sutton GG Delcher AL Dew IM Fasulo DP Flanigan MJ Kravitz SA Mobarry CM Reinert KH Remington KA Anson EL Bolanos RA Chou HH Jordan CM Halpern AL Lonardi S Beasley EM Brandon RC Chen L Dunn PJ Lai Z Liang Y Nusskern DR Zhan M Zhang Q Zheng X Rubin GM Adams MD Venter JC 《Science (New York, N.Y.)》2000,287(5461):2196-2204
We report on the quality of a whole-genome assembly of Drosophila melanogaster and the nature of the computer algorithms that accomplished it. Three independent external data sources essentially agree with and support the assembly's sequence and ordering of contigs across the euchromatic portion of the genome. In addition, there are isolated contigs that we believe represent nonrepetitive pockets within the heterochromatin of the centromeres. Comparison with a previously sequenced 2.9- megabase region indicates that sequencing accuracy within nonrepetitive segments is greater than 99. 99% without manual curation. As such, this initial reconstruction of the Drosophila sequence should be of substantial value to the scientific community. 相似文献
80.