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1.
Currently, antimicrobial-resistant staphylococci, particularly methicillin-resistant Staphylococcus pseudintermedius (MRSP), are frequently isolated from canine superficial pyoderma in Japan. However, little is known regarding the nasal prevalence of MRSP in pet dogs. Here, we determined the prevalence of antimicrobial-resistant staphylococci in nares and affected sites of pet dogs with superficial pyoderma. Of the 125 nares and 108 affected sites of pet dogs with superficial pyoderma, 107 (13 species) and 110 (eight species) staphylococci strains, respectively, were isolated. The isolation rate of S. pseudintermedius from pyoderma sites (82/110 strains, 74.5%) was significantly higher than that from nares (57/107 strains, 53.3%) (P<0.01). Notably, the prevalence of MRSP (18/57 strains, 31.6%) in nares was equivalent to that in pyoderma sites (28/82 strains, 34.1%). Furthermore, the phenotypes and genotypes of antimicrobial resistance in MRSP strains from nares were similar to those from pyoderma sites. Our findings revealed that the prevalence of antimicrobial-resistant staphylococci in the nares of pet dogs with superficial pyoderma is the same level as that in affected sites. Therefore, considerable attention should be paid to the antimicrobial resistance of commensal staphylococci in companion animals.  相似文献   
2.
The onset of severe injury to the superficial digital flexor tendon (SDFT) is extremely difficult to predict from slight changes in ultrasonographic findings in cases with no apparent clinical signs. This study investigated the relationship between an increased cross-sectional area (CSA) or edema in the subcutaneous tissue around the tendon and the subsequent onset of severe SDFT injury in Thoroughbred racehorses. Horses were classified into three groups based on ultrasound diagnosis (USD) findings: Group A included cases with enlarged tendons; Group B included cases with tendons of normal size but with prominent edema in the peritendinous tissue; and Group C (control group) included cases with no abnormal USD findings. The incidence of subsequent severe tendon injury was significantly higher in the horses in Groups A (25.7%, 28/101) and B (28.3%, 65/212) than in those in Group C (4.9%, 2/41). There were no significant differences in the median period and the median number of races from the first examination to the subsequent tendon injury between Groups A (140 days, 1 race) and B (120 days, 1 race). The results of this study revealed that horses with increased CSA and peritendinous edema are likely to suffer a subsequent severe tendon injury. Also, these two USD findings, i.e., increased CSA and peritendinous edema, indicate the risk of onset of severe SDFT injury.  相似文献   
3.
Someya  N.  Tsuchiya  K.  Yoshida  T.  Noguchi  M. T.  Akutsu  K.  Sawada  H. 《植物病害和植物保护杂志》2007,114(3):108-112
Journal of Plant Diseases and Protection - The antagonistic rhizobacterium, Pseudomonas fluorescens strain LRB3W1, controls cabbage Fusarium yellows caused by Fusarium oxysporum f. sp. conglutinans...  相似文献   
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In Japan, the lifetime cycle of most housing lasts around 20–30 years. A governing factor in this respect is poor durability due to old-fashioned use of the house. As a solution of this problem, houses can be built with a skeleton structure that allows free partition of spaces by future owners. To develop the skeleton structure effectively, multistory frames with spans of 6 to 10 m are required. For this reason, attention has been focused on the behavior of multistory timber frame structures. In this article, two types of wooden portal frame structures are proposed. Both structures have improved vertical columns with short horizontal members glued in. The aim of this study was to investigate structurally effective solutions with these types of columns. The first type of the new structure changed the location of the moment-transmitting ductile connection with the improved columns. The second type of structure used an extended panel zone. Nine portal frame specimens were tested. The stiffness values were improved by around 1.7 and 3.5 times when compared with the control, and the strength was improved by around 1.25 and 1.45 times.  相似文献   
6.
Morphological characteristics of macropores in forest soil profiles were investigated at Hitachi Ohta Experimental Watershed in Japan. Nine individual profiles at different locations (various spatial scales in a catchment) and twenty profiles at one site (a small spatial scale) were excavated to the bedrock to investigate density, origin, diameter, direction, and gradient of macropores. Macropore densities in a soil profile ranged from 3.5 to 29.1 per m and from 5.4 to 75.1 per m2, respectively. Subsurface erosion, root channels, and interactions between subsurface erosion and root channels accounted for 36.9, 36.5, and 19.0%, of the described macropores. The mean macropore diameter in organic-rich soil layer (17–20 mm) was larger than in the B horizon (11–14 mm) at both spatial scales. The dominant gradients of all macropores in the organic-rich soil layer and B horizon were at negative oblique angles. Approximately 90% of the macropores in the organic-rich soil layer and approximately 80% of the macropores in the B horizon fell within the range between −50 and 50 degree planar direction. Subsurface flow and root systems are believed to play important roles in determining the morphological characteristics of macropores. These characteristics appear to have variable influences in different soil horizons rather than at different spatial scales. A part of this paper was presented at the 103th (1992) and 105th (1994) Annual Meetings of Japanese Forestry Society.  相似文献   
7.
Environmental factors, such as global solar radiation, wind speed, air temperature, humidity, and CO2 concentration, were measured above and within the canopy of a tropical rainforest in Lambir Hills National Park, Sarawak, Malaysia. Few data concerning the environment of this forest have been reported. Intensive observations were carried out in 1998, 1999, and 2000 with the following results: (1) The fraction of global solar radiation reaching the upper layer of the canopy varied with global solar radiation above the canopy. Even though the global solar radiation above the canopy fluctuated, the fraction of that reaching the lower canopy and the ground was constantly approximately 5%. (2) The fraction of wind speed reaching each layer of the canopy increased with wind speed above the canopy. Little wind was usually present at the lower canopy. (3) The daytime air temperature at the canopy top was higher than that near the ground. The maximum difference between the air temperature at the canopy top and that at the ground was about 5°C, and the diurnal temperature ranges at the canopy top and those at the ground were about 8°C and about 5°C, respectively. The highest daytime water vapor pressure occurred within the canopy and particularly near the ground. Vertical gradients of water vapor pressure during the day were steep, probably because of high transpiration. (4) In the 1998 observation the minimum and the maximum CO2 concentrations were 360 ppm in the day and 450 ppm at night, while in the 2000 observation the minimum and the maximum CO2 concentrations were 350 ppm in the day and 540 ppm at night. The higher CO2 concentration in the daytime and the lower concentration at night observed during the 1998 observation period were probably due to reduced photosynthesis and soil respiration caused by exceptional dry conditions during the observation period.  相似文献   
8.
Summary The acoustic emissions (AEs) under partially compression were monitored with two softwood and one hardwood specimens in very eary stages of decay by a brown- and a white-rot fungus. Even slightly decayed specimens emitted AEs immediately after beginning of loading, typically when partial compression stress was applied to brown-rotted wood with the flat-headed attachment. With sound specimens of three wood species, only a few AEs were generated until the load reached at the proportional limit. These results suggest that AE monitoring will be one of the feasible means to detect the incipient stages of decay in a field test.The authors thank the Weyerhaeuser Research Grants Program for its aid in this investigation  相似文献   
9.
Fine roots are a key component of forested ecosystems, but available information is still limited. This study examined the production and mortality of fine roots less than 1 mm in diameter in a Japanese cedar (Cryptomeria japonica D. Don) plantation located on the Kanto Plain in central Japan. We used a minirhizotron technique in combination with soil coring, and collected data for 1 year (May 2002–May 2003). Fine root production and mortality were determined from changes in the lengths of individual fine roots on minirhizotron tubes. Both fine root production and mortality rates were greater in the upper soil than in lower soil levels. Both rates were seasonal, with higher values in summer than in winter; this trend was more pronounced in upper soil levels. These results suggest that environmental conditions, such as temperature or soil properties, affect the production and mortality rates of fine roots. Fine root production and mortality occurred simultaneously, and their rates were similar, which may have led to unclear seasonal changes in fine root standing crop estimates. Soil coring indicated that the fine root biomass of this stand was about 120 g m−2, of which 40% was from Japanese cedar. The estimated rates of dry matter production and mortality of total fine roots, including understory plants, were both approximately 300 g m−2 year−1.  相似文献   
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