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391.
Shirin Farzadfar Yasuhiro Tomitaka Mutsumi Ikematsu Ali Reza Golnaraghi Reza Pourrahim Kazusato Ohshima 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):45-55
Eight provinces of Iran were surveyed during 2003–2008 to find Brassicaceae reservoir weed hosts of Turnip mosaic virus (TuMV). A total of 532 weed samples were collected from plants with virus-like symptoms. The samples were tested for the
presence of TuMV by enzyme-linked immunosorbent assay using specific antibodies. Among those tested, 340 samples (64%) were
found to be infected with TuMV. Rapistrum rugosum, Sisymberium loeselii, S. irio and Hirschfeldia incana were identified as the Brassicaceae weed hosts of TuMV, and the former two plant species were found to be the most important
weed hosts for the virus in Iran. The full-length sequences of the genomic RNAs of IRN TRa6 and IRN SS5 isolates from R. rugosum and S. loeselii were determined. No evidence of recombination was found in both isolates using different recombination-detecting programmes.
Phylogenetic analyses of the weed isolates with representative isolates from the world showed that the IRN TRa6 and IRN SS5
isolates fell into an ancestral basal-Brassica group. This study shows for the first time the wide distribution and phylogenetic relationships of TuMV from weeds in the
mid-Eurasia of Iran. 相似文献
392.
Previously, we classified Pseudomonas syringae strains into at least three groups (I, II and U) by comparing DNA homology at the hrp cluster and its neighboring regions (Inoue and Takikawa 1999). However, heterogeneous strains remained in the undetermined
group (group U). We further classify group U, using pvs. syringae and coronafaciens as references. Comparison of restriction sites for regions of each pathovar revealed distinct differences. By using probes
from the two pathovars, comparisons of DNA homology at the regions separated two additional distinct groups (III and IV) from
group U. Therefore, P. syringae strains are classified into at least five groups.
Received 4 November 1999/ Accepted in revised form 27 January 2000 相似文献
393.
Takuya Maruo Yasuhiro Fukuyama Yuta Nishiyama Yuki Nemoto Eiichi Kanai Shinpei Kawarai Hideki Kayanuma Kensuke Orito 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(10):1117
Intraoperative acridine orange-photodynamic therapy (AO-PDT) and cribriform plate irradiation are used to treat canine intranasal tumors. The purpose of this study was to evaluate the effects of AO-PDT on intranasal tumors and the recurrence rate of tumors after this treatment. Treatments with AO-PDT were performed on 38 dogs through a narrow window of the dorsal nasal cavity. The median progression-free interval was 12 mo and recurrence was detected in 21 dogs. Based on computed tomography, recurrence in 16 dogs was biased to the following areas: lateral (n = 10), medial (n = 2), ventral (n = 0), rostral (n = 0), and caudal (n = 8). Side effects were mild and included subcutaneous emphysema and rhinitis. The median survival time was 24 mo. Although AO-PDT with cribriform irradiation is an effective treatment for intranasal tumors, AO-PDT techniques should be improved to treat the nasal cavity more uniformly and thoroughly. 相似文献
394.
395.
This article reports the concentration and composition of the isomers of cis-icosenoic acid (20:1) in the fatty acids of various species of Japanese marine animals. The main purpose of this study is to reveal the distribution of a positional isomer, cis-7-20:1 (c7-20:1), in marine animals. Because this isomer overlaps with the c9-20:1 isomer in gas chromatography (GC) on the commonly used polar capillary columns, less information is available on its occurrence and distribution. In this study, the monounsaturated fatty acids isolated by argentation thin-layer chromatography were analyzed by GC using a highly polar capillary column, SLB-IL111 (100 m long), with the highest polarity among the commercially available GC columns. A clear separation between the c7-20:1 and c9-20:1 isomers enabled the analysis of all the isomers of 20:1 present in marine animals. The results confirmed that the c7 isomer was a minor component in the 20:1 in the pelagic fish, which is rich in the c9 and/or c11 isomers as reported previously. In contrast, the c7 isomer was one of the major isomers in flatfish, shellfish, crabs, and brittle stars. In these samples, the c13 isomer also occurred at higher concentrations rather than the c9 isomer. Because such a specific pattern of the 20:1 positional isomers was generally observed in both benthic fish and its dietary animals, the c7 isomer in the benthic fish probably originated from its diet. These marine animals are used as food in Japan, and therefore the c7-20:1 isomer is consumed by humans. 相似文献
396.
Yasuhiro Ishiga Srinivasa Rao Uppalapati Takako Ishiga Carol L. Bender 《Journal of General Plant Pathology》2010,76(3):188-195
Coronatine (COR) functions as a virulence factor in the interaction of Pseudomonas syringae pv. tomato strain DC3000 with tomato and Arabidopsis. COR consists of two moieties, coronafacic acid (CFA) and coronamic acid (CMA).
Both COR and CFA function as structural and functional analogues of jasmonic acid (JA) and related signaling compounds such
as methyl jasmonate (MeJA) and JA-isoleucine (JA-Ile). The precise function of COR and whether MeJA functions as an analogue
of COR in disease development are not known. In this study, we analyzed whether the COR-defective mutant DB29, which is a
CFA− CMA− mutant of DC3000, could be complemented for virulence via the exogenous application of COR, CFA, or MeJA. When tomato seedlings
were inoculated with DB29 and supplemented with exogenous COR, the DB29 population multiplied in tomato seedlings and induced
disease phenotypes similar to wild-type DC3000. Although the addition of exogenous MeJA or CFA enhanced the multiplication
of DB29, wild-type disease phenotypes could not be restored with these compounds. Furthermore, inoculation of DB29 along with
exogenous COR, but not MeJA or CFA, suppressed the expression of defense-related genes and increased the accumulation of reactive
oxygen species, which are associated with severe chlorosis. Taken together, our results suggest that although COR targets
the jasmonate pathway by mimicking JA, the function of COR in disease development is distinctly different from MeJA or CFA. 相似文献
397.
Haruyama J Ohtake M Matsunaga T Morota T Honda C Yokota Y Abe M Ogawa Y Miyamoto H Iwasaki A Pieters CM Asada N Demura H Hirata N Terazono J Sasaki S Saiki K Yamaji A Torii M Josset JL 《Science (New York, N.Y.)》2009,323(5916):905-908
We determined model ages of mare deposits on the farside of the Moon on the basis of the crater frequency distributions in 10-meter-resolution images obtained by the Terrain Camera on SELENE (Selenological and Engineering Explorer) (Kaguya). Most mare volcanism that formed mare deposits on the lunar farside ceased at approximately 3.0 billion years ago, suggesting that mare volcanism on the Moon was markedly reduced globally during this period. However, several mare deposits at various locations on the lunar farside also show a much younger age, clustering at approximately 2.5 billion years ago. These young ages indicate that mare volcanism on the lunar farside lasted longer than was previously considered and may have occurred episodically. 相似文献
398.
We investigated the effects of selective logging on stand structure and regeneration in selectively logged subboreal forests
in Taisetsuzan National Park in Hokkaido in northern Japan. The basal area decreased and the size structure of trees altered
in the stands studied due to repeated, intense selective logging, in which larger trees were cut down as a priority. Sapling
density in the stands was much lower than that in primary forests. In the simple and multiple regression analyses that were
used to estimate the effects of selective logging on sapling density, sapling density had a significant positive correlation
with tree density and had little correlation with the density of logged stumps or the height ofSasa (dwarf bamboo) growing on the forest floor. These results suggest that the establishment sites around canopy trees influenced
the establishment of saplings, rather than the gaps caused by selective logging. However, both the coefficient of determination
and the standardized partial regression coefficient of multiple regression analysis were higher for the stand with a dense
cover ofSasa than for the stand with a sparse cover ofSasa. Thus, the success of regenerating forests with selective logging depends on both the site of advanced regeneration and the
light conditions that regulate growth. 相似文献
399.
To clarify the role of colluvium and saprolite in the hydrological processes of a forested mountain, the thickness and the
physical properties of them were investigated at the Tsukuba Experimental Basin. We measured their thickness using a penetrometer,
surveyed soil profiles, and analyzed undisturbed cylindrical samples for measurements of physical properties. At the zero-order
basin, which is mainly covered by volcanic ash, the colluvium is mostly over 1.0 m in thickness. Along the axis of the basin,
we found colluvium over 6.0 m thick. The saprolite thickness is heterogeneously distributed over the hillslopes and along
the axis of the hollow, where it is rather thick. The physical properties of shallow colluvium, deep colluvium and saprolite,
particularly bulk density and total porosity, are different. Thick colluvium and saprolite play an important role as a buffer
against direct runoff. 相似文献
400.
We report a method for compensating the birefringence of optical polymers by doping them with inorganic birefringent crystals. In this method, an inorganic birefringent material is chosen that has the opposite birefringence to that of the polymer and has rod-shaped crystals that are oriented when the polymer chains are oriented. The birefringence of the polymer is thus compensated by the opposing birefringence of the crystal. Birefringence is minimized in various polymer optical devices by adjusting process conditions, because it degrades the performance of devices. This method minimizes it, independent of process conditions, which potentially improves the productivity of devices. 相似文献