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31.
Masuda A Sukegawa T Mizumoto N Tani H Miyamoto T Sasai K Baba E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(11):1177-1182
An epidemiological investigation of 120 canine otitis externa cases in 1,370 dogs was done on the incidence rate, ear pinna shapes, breeds and their relationships. Eighty-five cases (12.6%) in 672 dogs with pendulous ears and 35 cases (5.0%) in 698 dogs with erect ears had otitis externa, and the difference between them was significant (P<0.05). Ninety-five auditory cerumen specimens were cultured for Malassezia pachydermatis (M. pachydermatis) and analyzed for concentrations of major fatty acids. Although rates of cases positive for M. pachydermatis in both ear pinna shapes were almost the same, i.e. 55.2% in the pendulous group and 53.6% in the erect group, the average total fatty acid level of the pendulous ear group was significantly (P<0.05) higher than that in the erect ear group after dismissing extraordinary levels in the Siberian husky. Isolated M. pachydermatis strains were examined for the effects of fatty acid supplementation on their growth. The majority of the strains utilized fatty acids and grew faster in fatty acid supplemented broth. These results suggest that M. pachydermatis, the predominant causative agent of canine otitis externa, prefers the auditory canal of dogs with lipid-rich earwax and grows fast, but growth strongly depends upon the canine breed. 相似文献
32.
We induced various flower morphologies in torenia (Torenia fournieri Lind.) by the application of forchlorfenuron (CPPU). Those morphologies were the combination of four basic morphological changes, the development of serrate petals, incised petals, a paracorolla, and an increased number of floral organs. These morphological changes occurred systematically depending on the floral stage at the time of CPPU application. Serrate petals were induced when CPPU was applied during the stages of corolla development, whereas application at younger stages induced petal incision. The serrate petal margin resulted from preferential proliferation of cells around the vascular bundles, whereas petal incision likely resulted from the lateral outgrowths of petal. A paracorolla was induced at the adaxial petal face when CPPU was applied between the sepal development stage and early corolla development. The paracorolla appears to have arisen from the lateral outgrowths of the stamen. The numbers of stamens, petals, and sepals increased when CPPU was applied at and before the differentiation of sex organs and the corolla. Enlargement of the floral meristem probably caused this increase. Application of N6-benzylaminopurine and zeatin did not induce these morphological changes. 相似文献
33.
Takao Tsukiboshi Yoshiaki Chikuo Yoko Ito Yosuke Matsushita Koji Kageyama 《Journal of General Plant Pathology》2007,73(4):293-296
Root and stem rot with wilt of above ground parts of cultivated chrysanthemums was first found in Ibaraki, Toyama and Kagawa
prefectures, Japan in 2002 and 2003. Pythium species were isolated from the diseased tissues and identified as P. dissotocum, P. oedochilum, P. sylvaticum, P. ultimum var. ultimum and asexual strains of P. helicoides based on their morphologies and sequences of rDNA-ITS region. All the Pythium species were strongly pathogenic to chrysanthemums in pot conditions and were reisolated from the inoculated plants. Because
Pythium root and stem rot of chrysanthemum has never been reported in Japan, we propose that this is a new disease that can
be caused by the five Pythium species. 相似文献
34.
Soil strength and water content are important indices for assessing soil resistance to root growth and soil compaction both of which affect other soil properties. Therefore, simultaneous measurement of soil penetration resistance (PR) and soil water content can aid agricultural land management. We measured PR with a conventional cone penetrometer, followed immediately by determining water content using a modified TDR probe inserted into the penetrometer hole. From the results of a field feasibility test, soil water content was measured satisfactorily and correlated well with data obtained by the gravimetric method, except for those data from near the surface owing to soil disturbance when the cone penetrometer was extracted after the PR measurements. Field results demonstrate that PR and soil water content have three‐dimensional variability, with a markedly different distribution pattern between cultivated and subsoil layers at the field scale. Overall, the variability in the PR and soil water data is similar to that reported in previous studies. We conclude that our method produces results helpful to field management of soil and water because it is based on a simple and easy technique for the simultaneous measurement of soil water content and PR. 相似文献
35.
Effect of particle shape on linear expansion of particleboard 总被引:2,自引:0,他引:2
Hinoki (Japanese cypress) strand with 0.6mm thickness was hammer-milled to prepare three types of particles that had the same thickness but different lengths and widths. Screen analysis and image analysis were conducted to evaluate the shape and distribution of the particle dimensions. Laboratory-scale particleboards were fabricated at three density levels using these particles. To determine the true effect of particle shape on the linear expansion (LE) of the board, these boards exhibited almost the same temperature behavior during pressing, the same density profile, and the same bending properties at each board density level. LE at 40°C and 90% relative humidity of the board was found to be affected by the particle shape. The board composed of small particles showed a larger LE at the same density level. It was considered that the out-of-plane orientation angle of the particles affected the LE of the boards. Thickness swelling and internal bond strength were also affected by the particle shape.Part of this report was presented at the 50th annual meeting of the Japan Wood Research Society, Kyoto, April 2000 相似文献
36.
Fumiaki Nakatsubo Kenichi Enokita Koji Murakami Keizo Yonemori Akira Sugiura Naoki Utsunomiya Suranant Subhadrabandhu 《Journal of Wood Science》2002,48(5):414-418
The structural variety of the condensed tannins (proanthocyanidins) in the fruits of 16Diospyros species are reported. Eleven species contained condensed tannins mostly consisting of a mixture of catechin (CA) and gallocatechin (GCA) repeating units; the other five species did not. The GCA content in the CA-GCA total varied from 0.3% to 84.6%. The number of esterified gallic acid per one flavan repeating unit (degree of galloylation, DG) ranged from 0.01 to 0.89. The GCA content was found to be proportional to the DG values. Thus, 16Diospyros species tested may be classified into five groups by the analytical data of their condensed tannins. It may be interesting to compare their structural characteristics with those of the condensed tannins in other fruits, leaves, woods, and barks from the viewpoint of their biosynthesis and function in the plants.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1995 相似文献
37.
Koji?HayashiEmail author Masaharu?Ohmi Hiroshi?Tominaga Kiyoharu?Fukuda 《Journal of Wood Science》2003,49(5):398-404
We investigated the bending properties of composite boards produced by reinforcing both sides of corrugated particleboard with medium-density fiberboard (MDF). Thickness swelling and linear expansion (LE) were measured to assess the dimensional stabilities of the composite board. Although the apparent density of the composite board was 0.48g/cm3, its strength was found to be equivalent to that of 18-type particleboard as described in JIS A 5908. The boards parallel/perpendicular anisotropy in strength was 0.9. The modulus of rupture (MOR) of the composite board increased with board density only up to a certain density, beyond which the MOR was constant. On the other hand, the thickness swelling of both corrugated particleboard and the composite board was smaller than that of flat-type particleboard, satisfying the JIS A 5908 standard of 12%. Linear expansion (soaking in water of ordinary temperature for 24h) of corrugated particleboard was 0.7%–0.9% in the parallel direction and 2.1%–3.1% in the perpendicular direction; hence, anisotropy in linear expansion existed in the corrugated particleboard. The linear expansion of the composite board was 0.6%–0.9% in the parallel direction and 1.8%–2.5% in the perpendicular direction. Although the LE of the composite board was lower than that of corrugated particleboard, it is necessary to improve the LE of composite board for practical use. 相似文献
38.
Koji Yoshida Shoko Inaba Chisato Takenaka Takafumi Tezuka 《Journal of Forest Research》2005,10(2):157-161
To clarify the nutrient status in momi fir (Abies firma Sieb. et Zucc.) seedlings under complex stress conditions of acid fog with soil acidification or nitrogen loading, we exposed seedling shoots to simulated acid fog (pH 3) and simultaneously loaded the soil with acid or excess nitrogen for 17 months. Proton and nitrogen loading reduced K concentration in soil, but these treatments had little effect on the nutrient status of fine roots in momi fir seedlings. Acid fog exposure resulted in reduced concentrations of Mg, Al, and Fe in current-year needles and Mg, Al, Cu, Fe, and Zn in 1-year-old needles. The complex effects of acid fog exposure with proton or nitrogen loading on nutrient status were relatively slight. However, elements such as Al and Cu notably reflect the effects of proton loading. These results show that the nutrient status of trace elements, rather than major elements, in needles of momi fir seedlings is sensitive to exposure to acid fog or proton loading. 相似文献
39.
40.
ABSTRACT: The life history and ecology of the glowbelly Acropoma japonicum a commercially important fishery resource, were investigated in the Uwa Sea, Japan. Newly settled juveniles (0+ ) appeared at the end of the breeding season and reached maturity in the next season, i.e. when they became yearlings (1+ ). The yearlings made a gametic effort comparable to that of older fish. During the breeding season, the somatic conditions were more deteriorated for males than for females. That the deterioration of male somatic conditions was not attributable to a sexual difference in energy gain from feeding suggests that the males incurred higher energetic costs of reproduction despite their relatively low gonadosomatic indices. Such an energy depletion may increase the mortality risk, resulting in female-biased sex ratios in the older age classes. Most of the 1+ fish disappeared in winter following their first breeding. For A. japonicum , the observed precocity and short life span is notable because it is a higher consumer that is generally expected to show later maturation and longer life. As possible explanations for their disappearances, predation and postbreeding emaciation were less likely. While fishing is one of the most influential factors, the possibility of age-specific migration toward deeper waters remains to be examined. 相似文献