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91.
Yasuhiro Utsumi Shinya Koga Naoaki Tashiro Atsushi Yamamoto Yukie Saito Takanori Arima Hirokazu Yamamoto Masahiko Kadomatsu Nao Sakanoue 《Journal of Wood Science》2006,52(6):477-482
Of all plant materials used to cover the roofs of traditional Japanese buildings, Japanese cypress (Chamaecyparis obtusa) bark, hiwada, has the longest service life and has been used from ancient times. However, wood and bark properties after hiwada harvest have not been evaluated in detail. We studied whether decortication for hiwada production in winter affected xylem and phloem formation. Decorticated trees still preserved all inner bark and part of the
outer bark, and both decorticated and control trees had similar annual ring structures at all stem heights in the xylem and
phloem. In both xylem and inner bark, no significant difference in ring width at any stem height was found between annual
rings before and after decortication. Thus, this study revealed that the decortication of bark for hiwada production does not affect the formation of xylem and the inner and outer bark if decortication is carried out by highly
skilled workers in winter. 相似文献
92.
K. Kusano M. Nomura K. Toju Y. Ishikawa Y. Minamijima S. Yamashita S. Nagata 《Journal of veterinary pharmacology and therapeutics》2016,39(3):264-270
Procaterol (PCR) is a beta‐2‐adrenergic bronchodilator widely used in Japanese racehorses for treating lower respiratory disease. The pharmacokinetics of PCR following single intravenous (0.5 μg/kg) and oral (2.0 μg/kg) administrations were investigated in six thoroughbred horses. Plasma and urine concentrations of PCR were measured using liquid chromatography–mass spectrometry. Plasma PCR concentration following intravenous administration showed a biphasic elimination pattern. The systemic clearance was 0.47 ± 0.16 L/h/kg, the steady‐state volume of the distribution was 1.21 ± 0.23 L/kg, and the elimination half‐life was 2.85 ± 1.35 h. Heart rate rapidly increased after intravenous administration and gradually decreased thereafter. A strong correlation between heart rate and plasma concentration of PCR was observed. Plasma concentrations of PCR after oral administration were not quantifiable in all horses. Urine concentrations of PCR following intravenous and oral administrations were quantified in all horses until 32 h after administration. Urine PCR concentrations were not significantly different on and after 24 h between intravenous and oral administrations. These results suggest that the bioavailability of orally administrated PCR in horses is very poor, and the drug was eliminated from the body slowly based on urinary concentrations. This report is the first study to demonstrate the pharmacokinetic character of PCR in thoroughbred horses. 相似文献
93.
94.
De Pontieu B McIntosh SW Carlsson M Hansteen VH Tarbell TD Schrijver CJ Title AM Shine RA Tsuneta S Katsukawa Y Ichimoto K Suematsu Y Shimizu T Nagata S 《Science (New York, N.Y.)》2007,318(5856):1574-1577
Alfvén waves have been invoked as a possible mechanism for the heating of the Sun's outer atmosphere, or corona, to millions of degrees and for the acceleration of the solar wind to hundreds of kilometers per second. However, Alfvén waves of sufficient strength have not been unambiguously observed in the solar atmosphere. We used images of high temporal and spatial resolution obtained with the Solar Optical Telescope onboard the Japanese Hinode satellite to reveal that the chromosphere, the region sandwiched between the solar surface and the corona, is permeated by Alfvén waves with strong amplitudes on the order of 10 to 25 kilometers per second and periods of 100 to 500 seconds. Estimates of the energy flux carried by these waves and comparisons with advanced radiative magnetohydrodynamic simulations indicate that such Alfvén waves are energetic enough to accelerate the solar wind and possibly to heat the quiet corona. 相似文献
95.
To determine the effect of vegetation types on the oviposition by the butterfly, Sasakia charonda, the host plants were planted in a meadow (site A), a small broadleaf forest (site B), a large broadleaf forest (site C), and at the edge of a Cryptomeria japonica forest adjacent to the large broadleaf forest (site D). The number of S. charonda eggs per planted host tree was higher at sites C and D than at site B, and no eggs were found at site A. The densities of both male and female adults were significantly higher at site C than at the other sites, and no adults were found at site A. A mark-and-recapture method estimated that the dispersal distances of wild adults were within 100m, although these adults already had heavily torn wings when they were initially captured. In one case, a female adult was caught 730m from the release point, a distance greater than that between sites A and C. When the wild adults were initially captured and when recaptured, they sipped the sap of Quercus acutissima. The capture and recapture points of most of the recaptured wild adults were in the Q. acutissima stand in the large broadleaf forest, where site C was located. Our observations at site A and the results of the mark-and-recapture study suggested that the flight range of mature adults was limited to large broadleaf forests containing Q. acutissima stands and long-distance dispersal seldom occurred or that the flyways of female adults searching for host trees were restricted to the vicinity of broadleaf forest areas, resulting in no visits to isolated host trees. Finally we discussed the selection of suitable host tree-planting sites for the conservation of this butterfly. 相似文献
96.
97.
Yoshikawa Y Horiuchi M Ishiguro N Kadohira M Kai S Mizusawa H Nagata C Onodera T Sata T Tsutsui T Yamada M Yamamoto S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):959-968
The Food Safety Commission (FSC) of Japan, established in July 2003, has its own initiative to conduct risk assessments on food stuffs known as "self-tasking assessment". Within this framework, the FSC decided to conduct a risk assessment of beef and beef offal imported into Japan from countries with no previous BSE reports; thus, a methodology was formed to suit to this purpose. This methodology was partly based on the previous assessments of Japanese domestic beef and beef imported from U.S.A./Canada, but some modifications were made. Other organizations' assessment methods, such as those used for BSE status assessment in live cattle by the OIE and EFSA's GBR, were also consulted. In this review, the authors introduce this alternative methodology, which reflects (1) the risk of live cattle in the assessed country including temporal risks of BSE invasion and domestic propagation, with the assessment results verified by surveillance data, and (2) the risk of beef and beef offal consisting of cumulative BSE risk by types of slaughtering and meat production processes implemented and the status of mechanically recovered meat production. Other possible influencing factors such as atypical BSE cases were also reviewed. The key characteristic of the current assessment is a combination of the time-sequential risk level of live cattle and qualitative risk level of meat production at present in an assessed country. 相似文献
98.
Kushida M Wanibuchi H Wei M Kakehashi A Ozaki K Sukata T Miyata K Ogata K Uwagawa S Fukushima S 《Journal of toxicologic pathology》2009,22(1):65-70
Epidemiological studies suggest that alcohol consumption increases the risk of developing colorectal cancer. However, the data are confounded by numerous cosegregating variables. To cast further light on the relationships between alcohol intake and colon cancer development, 21-day-old male F344/DuCrj rats were fed 200 ppm 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) in their diet for 8 weeks and doses of 0, 0.1, 0.3, 1, 3, 10 and 20% of ethanol in their drinking water ad libitum for 16 weeks thereafter. The rats were sacrificed after 24 weeks of experiment, and aberrant crypt foci (ACF), surrogate lesions for colon cancer, were examined under a light microscope at low magnification. Ethanol was found not to affect the ACF formation at any dose compared with the initiated-controls. Furthermore, ethanol did not alter colon epithelial cell proliferation. These data, obtained by analysis of a colon cancer surrogate marker lesion, indicate that ethanol lacks promotion activity for MeIQx-initiated rat colon carcinogenesis. 相似文献
99.
Tomohiro MITANI Makoto TAKAHASHI Koichiro UEDA Hiroki NAKATSUJI Seiji KONDO Masahiko OKUBO 《Animal Science Journal》2005,76(4):331-337
The effects of supplementary corn silage (CS) of either 2 or 4 kg of dry matter (DM; S + 2 and S + 4, respectively) above the energy requirement for milk production and maintenance for grazing dairy cows (S) were determined. Time‐restricted grazing was used to compare the feed intake, milk production, and nitrogen and energy use of lactating cows. The experiment was carried out on two different pastures using a 3 × 3 Latin square design for each pasture. Cows were grazed for 5 h on a rotational grazing system and were fed concentrate (1 kg per 5 kg of milk yield). Herbage intake was measured using a weighing technique. To calculate the energy and nitrogen use, whole feces and urine were collected. There was no statistical effect of the pastures. Herbage intake decreased by the addition of CS (P = 0.02). The reduction of herbage DM intake per unit consumption of supplementary CS towards the S group were 0.80 and 0.45 kg for the S + 2 and S + 4 groups, respectively. The total DM intake for the S + 4 group was higher than that for the S and S + 2 groups (P = 0.02). Milk yield did not differ among treatments, even though the total DM intake for the S + 4 group was higher than that of the S and S + 2 groups. Nitrogen and energy use did not differ with the addition of CS. 相似文献
100.
Ishioka T Yoshizumi M Izumi S Suzuki K Suzuki H Kozawa K Arai M Nobusawa K Morita Y Kato M Hoshino T Iida T Kosuge K Kimura H 《Veterinary microbiology》2005,110(1-2):27-33
Koi herpesvirus (KHV), which is believed to be an emerging virus, causes fatal diseases in carps. Since the 1990s, the presence of KHV has been confirmed in several countries. In Japan, from 2003 to 2004, large outbreaks of KHV infection in farmed carps resulted in the death of numerous fishes. From April to May 2004, we collected 43 dead or dying carps exhibiting typical symptoms of KHV infection in Gunma prefecture. To conduct a molecular epidemiologic study of KHV in our prefecture, we amplified DNA polymerase and the major envelope protein genes of KHV derived from carp gills using newly designed primers. We also performed sequence analysis of both genes of KHV. Sensitivity of our PCR method for amplification of DNA polymerase and the major envelope protein genes of KHV was 3 x 10(2) (100 fg) and 3 x 10(3) (1000 fg) copies of KHV genome, respectively. We detected both DNA polymerase and major envelope protein genes in 37 of 43 carps (86%). No mutation was found in both the genes sequenced from 11 strains, which included two foreign strains and one domestic strain. The results suggested that KHV strains derived from carps in our prefecture were closely related genetically to the other KHV strains. 相似文献