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排序方式: 共有70条查询结果,搜索用时 13 毫秒
1.
Une Y Murakami M Uemura K Fujitani H Ishibashi T Nomura Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(8):905-907
A polymerase chain reaction (PCR)-based method using a herpesvirus consensus primer was assessed for the identification of herpesviral infections in tortoises. A single band of about 230 bp was detected in PCR products from two out of twenty swabs taken from the oral cavity, three out of three paraffin-embedded tissue sections from the liver (two cases) and oral mucosa (one case), and one out of two fresh tissue samples from the oral mucosa. Nucleotide sequencing of these PCR products indicated that the herpesvirus present in these tortoises might belong to the alphaherpesvirinae. PCR using swabs and biopsy tissues was a sensitive and highly specific method for the diagnosis of herpesviral infections in tortoises. 相似文献
2.
In the tropical canopy tree, Dryobalanops aromatica Gaertn. f., upper-canopy leaves (UL) develop under sunlit conditions but are subjected to self-shading within the crown as they age. In contrast, lower-canopy leaves (LL) are exposed to uniform dim light conditions throughout their life span. By comparing leaf morphology and physiology of UL and LL, variations in leaf characteristics were related to leaf age and self-shading. Mass-based chlorophyll (chl) concentration and the chlorophyll/nitrogen (chl/N) ratio were lower and the chl a/b ratio was higher in UL than in LL. In UL, the chl/N ratio gradually increased and the chl a/b ratio gradually decreased with leaf aging, whereas these ratios remained unchanged with leaf age in LL. The effective quantum yield of photosystem II (PSII) (DeltaF/F(m)') at a given irradiance remained unchanged with leaf age in LL, whereas DeltaF/F(m)' changed with leaf age in UL. These data indicate N reallocation within the leaves from carbon fixation components to light harvesting components and a dynamic regulation of photochemical processes of PSII in response to increased self-shading of UL. Despite the difference in light environment with leaf age between UL and LL, maximum photosynthetic rates and nitrogen-use efficiency decreased with leaf aging in both UL and LL. Constancy in the chl/N ratio with leaf age in LL indicated that the decrease in photosynthetic capacity was caused by effects other than shading, such as leaf aging. We conclude that N reallocation and acclimation of PSII to self-shading occurred even in mature leaves, whereas the change in photosynthetic capacity with leaf age was more conservative. 相似文献
3.
We investigated how shoot gross morphology and leaf properties are determined in Fagus japonica Maxim., a deciduous species with flush-type shoot phenology, in which all leaves are produced in a single flush at the start of each season. We examined relationships between current-year shoot properties and local light environment in a 14-m tall beech tree growing in a deciduous forest. Leaf number (LN), total leaf area (TLA), and total leaf length (SL) of the current-year shoot increased with increasing photosynthetic photon flux density (PPFD). Leaf thickness, dry mass per leaf area and nitrogen content on a leaf area basis increased, whereas the chlorophyll/N ratio decreased with increasing PPFD. To separate the effects of current-year PPFD from those of previous year(s), we artificially shaded a part of the uppermost leaf tier. Reciprocal transfers of beech seedlings between controlled PPFD regimes were also made. Characteristics of shoot gross morphology such as LN, TLA and SL were largely determined by the PPFD of the previous year. The exception was the length of the longest "long shoots" with many leaves, in which elongation appeared to be influenced by both previous-year and current-year PPFD. In contrast, leaf properties were determined by current-year PPFD. The ecological implications of our findings are discussed. 相似文献
4.
We used GIS on a regional scale to estimate and compare supply potentials and costs of small-scale logging systems, a mini-forwarder and a 4-ton truck operated by private logging contractors, and manual logging and a light truck operated by individual forest own- ers, with the mechanized operational system of the Forest Owners' Asso- ciation. Total potential yields of timber and logging residues were esti- mated as 418,895 m3 and 254,962 m3, respectively. The economic bal- ances were estimated and available amounts were projected as supply potentials from profitable sub-compartments. As a result, available amounts of timber and logging residues were estimated at 375,466 m3 (89.9%) and 203,850 m3 (80.0%), respectively. Because their transport expenses were lower than for other systems the most profitable sub-compartments were operated by private logging contractors who sold logging residues at a plant. The profitable sub-compartments operated by individual forest owners were few because the extracting distances were usually greater than 20 m. Raising logging residue prices from 3,000 yen·m-3 to 4,080 yen·m-3 or 6,800 yen·m-3, and establishing forest roads, which reduced some extracting distances to less than 20 m, increased the number and area of profitable sub*compartments, and increased available amounts of logging residues. 相似文献
5.
Chikara Nakahata Kazuhiro Aruga Ryo Uemura Masashi Saito Kanae Kanetsuki 《Small-Scale Forestry》2014,13(2):251-266
This study examines the optimal method to extract logging residues from small, fragmented and scattered forests separately from the mechanized operational systems used on aggregated forestry operation sites. First, small-scale logging systems operated by a private logging contractor and an individual forest owner were investigated. Regression equations for estimating felling and processing cycle times were established as a function of stem and log volumes, respectively. Equations to estimate the forwarding and transporting cycle times were established as a function of the forwarding and transporting distances using the forwarding and transporting velocities, respectively. Then, equations to estimate productivities and costs were established with the cycle times, volumes and hourly operational expenses consisting of labour and machinery expenses. Finally, costs of the small-scale systems—mini-forwarder and 4 t truck operated by a private logging contractor, and manual logging and light truck operated by an individual forest owner—were estimated and compared with the mechanized operation system operated by the Forest Owners’ Association. The mechanized operation system was found to have the highest cost and could not compete for small forestry operational sites and small stem volumes. The small-scale systems could be effective for harvesting small areas. This was especially true when conducting extracting operations without machines, as done by the individual forest owner, and transporting operations by a private logging contractor, in which the hourly income of the individual forest owner was higher than the hourly labour expenses. 相似文献
6.
Yosuke Sasaki Tadaaki Tokunaga Ryoko Uemura Masuo Sueyoshi 《Animal Science Journal》2014,85(3):213-218
We investigated the reproductive and lifetime performances of Kagoshima Berkshire gilts and sows. We examined 20 605 parity records of 4419 pigs for 2008 to 2012 on a farrow‐to‐finish commercial farm. The mean parity (± SD) of all animals was 3.0 ± 2.1. For farrowing performance, the highest numbers of total pigs born and pigs born alive were found in sows with parities 5 and 6 and with parity 3–6, respectively (P < 0.05). Regarding weaning and mating performance, sows with parity 2 had the lowest preweaning mortality (P < 0.05). The longest weaning‐to‐first‐mating interval was found in parity 1 pigs, and the interval decreased as parity increased (P < 0.05). Parities 0 and 1 pigs had the lowest farrowing rate and those with parity 4 had the highest farrowing rate (P < 0.05). The mean parity at culling, total number of pigs born alive in a lifetime, and nonproductive days in a lifetime were 5.5 ± 2.93, 49.2 ± 24.72 pigs, and 132.1 ± 83.34 days, respectively. These animals had a lower litter size and fertility that the F1 crossbred sows mainly used in Japan, but a similar tendency for performance by parity. 相似文献
7.
T Uemura S Suzuki T Ohnishi 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1990,37(6):468-472
Peripheral blood samples from dogs infected with Babesia gibsoni were analyzed by a flow cytometer for the percentage of reticulocytes after staining with a membrane-permeable fluorochrome, thiazole orange. Though thiazole orange has been reported to stain human reticulocytes and Plasmodium-infected erythrocytes, number of positive cells determined by the flow cytometry did not include that of erythrocytes infected with Babesia gibsoni. Analysis of 51 samples revealed a correlation coefficient of 0.96 as compared to the conventional determination by light microscopy. Separation of reticulocytes from Babesia gibsoni-infected erythrocytes by flow cytometry with or without the stain remained unresolved. 相似文献
8.
9.
Nagatomo H Takegahara Y Sonoda T Yamaguchi A Uemura R Hagiwara S Sueyoshi M 《Veterinary microbiology》2001,82(3):223-232
A comparison of the persistence of mycoplasmas in animals was carried out. When inoculated into liquid media, strains of Mycoplasma bovis, M. arginini, Acholeplasma laidlawii, and A. axanthum persisted for 59-185 days post-inoculation. The survival periods were not significantly influenced by temperature (4, 30, 37 degrees C, and room temperature). The survival periods for M. bovigenitalium, M. gallisepticum, M. bovirhinis, and M. gateae ranged from <7 to 185 days depending on medium components and temperature. Further, it was determined that strains of M. bovigenitalium, M. bovis, M. bovirhinis, M. arginini, and A. laidlawii persisted in a dry paper disc for at most 28, 126, 154, 56 and over >168 days at 4 degrees C, respectively. At 4 degrees C, strains of M. gallisepticum, M. columborale, M. edwardii, M. felis, and M. gateae survived for at most 28, 21, 42, 28, 28 and 70 days, respectively. At 30 degrees C, strains of M. bovis, M. bovirhinis, M. arginini, A. laidlawii, and M. gallisepticum persisted for at most 28, 84, 56, >168 and 14 days, respectively, but strains of M. gallisepticum, M. columborale, M. edwardii, M. felis, M. gateae, and U. diversum did not survive for more than 14 days. In an outdoor environment, strains of M. bovirhinis and A. laidlawii survived for at most 28 and 14 days, respectively. Finally, it was found that 14 isolates of M. gallisepticum persisted for periods similar to those of the reference strains. The results under dry conditions at a variety of temperatures presented contribute to understanding the epizootiology of mycoplasmal infections in the field. 相似文献
10.
Hideaki Korai Kimihiro Uemura Takuji Esashi Masaharu Suzuki 《Journal of Wood Science》1999,45(5):402-410
The purpose of this study was to reveal the effects of various levels of mat-moisture content (m.m.c.) and the closed-press system for making single- or three-layer particleboard on the density profile, thickness swelling, specific moduli of elasticity (MOE) and rupture (MOR) and internal bond strength. Internal gas pressure was measured in an enclosed frame; and the larger the m.m.c., the higher the internal gas pressure became. When rising water vapor (steam) struck particles, it plasticized them and cured the adhesive, resulting in improved interparticle contact. The vertical density gradient in the three-layer board was larger than that in the single-layer board. As for thickness swelling by cold-water soaking, the single-layer boards were less affected than the three-layer boards and showed good dimensional stability with increased m.m.c. The open-system boards swelled more than the closed-system boards. The closed-system single-layer board made at high m.m.c. returned nearly to the prime thickness by air-drying after cold-water soaking. Specific MOE and MOR were larger at 15% or 10% m.m.c. than those at other m.m.c. Considerable reductions of specific MOR and MOE of the closed-system three-layer board were observed at 20% or 25% m.m.c.Part of this report was presented at the 45th annual meeting of the Japan Wood Research Society, Tokyo, April 1995 and at the 48th annual meeting of the Japan Wood Research Society, Shizuoka, April 1998 相似文献