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101.
Tsunehisa Miki Hiroyuki Sugimoto Keisuke Kojiro Yuzo Furuta Kozo Kanayama 《Journal of Wood Science》2012,58(5):391-398
Enthalpy relaxation of dry wood has been investigated by temperature-modulated differential scanning calorimetry. The reversing and non-reversing heat flow changes revealed that enthalpy relaxation occurred in dry wood, which did not exhibit any clear glass transitions. This enthalpy relaxation behavior seemed to differ significantly from those of previously reported isolated lignins, which implies that the microstructure of dry wood possesses a rigid amorphous state derived from interactions among wood components. The observed enthalpy relaxation is considered to be related to other components besides lignin, and the time-dependent physical properties due to unstable states or physical aging of wood originate not only from lignin but also from other components, such as cellulose and hemicellulose and the interactions between them. 相似文献
102.
Ueda MU 《Tree physiology》2012,32(7):859-866
Nitrogen (N) retranslocation within tree canopies has been intensively studied and assumed to function as a one-way process (e.g., from older to newer leaves). However, recent studies have found that both N output and input occur in individual leaves, suggesting that 'gross' N retranslocation exists behind 'net' N retranslocation. In the present study, the amount and direction of gross N retranslocation within a canopy of deciduous oak Quercus serrata Thunb. ex. Murray saplings were investigated. Labeling was conducted with leaves of Q. serrata saplings cultivated under conditions of low-N (LN) or high-N (HN) fertility. Subsequently, N movement within the canopy was traced. Leaves at two different positions in the canopy (top and lateral) were labeled to determine the direction of gross N retranslocation. To detect seasonal differences, the leaf-labeling experiment was conducted twice during the early and late phases of the growing season. In addition, to compare the quantitative importance of gross N retranslocation and root N uptake, the latter was determined by labeling Q. serrata roots. The N-labeling experiment revealed gross N retranslocation among leaves, i.e., from top to lateral, lateral to top and lateral to lateral positions. Gross N retranslocation was quantitatively more important than root uptake, especially for plants cultivated at LN fertility. Season also affected the amount of gross N retranslocation, and these effects differed between LN and HN fertilities. These findings suggest that N allocation within a canopy is controlled dynamically by both gross N output and input. The mechanisms controlling gross N output and input likely function as key determinants of N allocation within a tree canopy. 相似文献
103.
T Sasaki K Yoshizawa Y Kinoshita H Miki A Kimura T Yuri N Uehara A Tsubura 《Journal of toxicologic pathology》2012,25(2):179-182
An intracranial lipomatous hamartoma was found in the third ventricle of a 7-week-old female BALB/cAnNCrlCrlj mouse. The nodule was composed of mature white adipose cells, which contained one large fat droplet, and there was no evidence of cytological atypia. The brain parenchyma at the retrosplenial granular cortex and the hippocampus in the cerebrum were slightly compressed, and the choroid plexus was dislocated downward. Scattered capillary vessels penetrated the nodule from the surrounding tissue. Based on these findings, the lesion was diagnosed as a lipomatous hamartoma that occurred from the roof of the third ventricle. This extremely rare tumor-like nodule represents an overgrowth of the mature adipocyte population as a malformation rather than a true neoplasm. 相似文献
104.
Bisphenol A (BPA) is a xenoestrogen commonly used in food storage plastics. The present study was conducted to clarify the effects of BPA administration to pregnant mice on serum calcium (Ca) and Ca metabolism of the gut and kidney. From 6.5 to 16.5 days post coitus (dpc), pregnant mice were administered at 2 mg or 20 mg/kg body weight/day of BPA. Serum Ca was decreased in mice treated with 20 mg BPA at 17.5 dpc, but no remarkable differences were detected in the alkaline phosphatase activity and vitamin D receptor protein expression in the duodenum and jejunum. The messenger RNA (mRNA) expressions of calcium binding protein (CaBP‐9k) and active vitamin D synthesis enzyme (CYP27B1) in the kidney were increased in mice treated with 20 mg BPA. The mRNA expressions of occludin and junction adherence molecular A (JAM‐A) in the duodenum and ileum, which regulate paracellular transport, were increased in mice treated with 20 mg BPA. However, the administration of 2 mg BPA had no effect on serum Ca and mRNA expressions of relative genes in Ca metabolism. These results imply that BPA administration at 20 mg/kg body weight/day during pregnancy decreases serum Ca in pre‐delivery mice, which may be partly due to decreased paracellular Ca absorption. 相似文献
105.
Soichi Tanaka Masako Seki Tsunehisa Miki Kenji Umemura Kozo Kanayama 《Journal of Wood Science》2017,63(6):644-651
This study has focused on solute diffusing into cell walls in solution-impregnated wood under conditioning, process of evaporating solvent. The amount of the diffusion is known to be determined by the solute diffusivity and the solute-concentration difference between cell walls and cell cavities. Purpose of this paper was to clarify the effect of temperature only on the solute diffusivity that is directionally related to the thermal vibration of the solute molecule. The cross-cut block of hinoki (Chamaecyparis obtusa), polyethylene glycol (PEG1540), and water was employed as wood sample, solute, and solvent, respectively. The sample impregnated with a 20 mass% solution was conditioned at 20, 35, or 50 °C to finish the solute diffusion evaluated using the dimension of the sample that was conditioned followed by drying in a vacuum. To unify the solute-concentration difference, for all temperatures, the equilibrium moisture content was unified and the solvent-evaporation rate was controlled in three ways during conditioning. The solute diffusivity was higher in order of 35, 50, and 20 °C, which was evaluated by the solute diffusion at the same evaporation rate. It is clarified that the diffusivity increases with increasing the dimension of cell walls rather than with increasing the thermal vibration of solute molecule. 相似文献
106.
Yosuke Kikuchi Satomi Nozaki Miki Makita Shoji Yokozuka Shin-ichi Fukudome Takashi Yanagisawa Seiichiro Aoe 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):161-165
Metabolic syndrome is a risk factor for cardiovascular diseases and has become increasingly common in Japan. Epidemiological studies show inverse associations between intake of whole wheat grains and metabolic syndrome, but few dietary intervention trials have investigated the effect of whole wheat grain consumption. It was investigated whether a diet in which refined wheat bread (RW diet) was substituted by whole grain wheat bread (WW diet) would reduce visceral fat obesity in Japanese subjects. A randomized double-blind placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI)?≥?23 kg/m2. Subjects were randomly assigned WW (WW group) or RW diets (RW group) for 12 weeks. Blood samples and computed tomography scans were obtained every 6th week. The WW group showed decrease (?4 cm2) in visceral fat area (VFA) (p <?0.05), whereas the RW group showed no significant changes. These time-dependent changes were significantly different between the groups. WW diet led to significant and safe reductions in VFA in subjects with BMI?≥?23 kg/m2. WW diet may contribute to preventing visceral fat obesity. 相似文献
107.
Objective
To compare the effectiveness of ultrasound- and electrostimulation-guided nerve blocks of the brachial plexus and to determine whether ultrasound guidance is feasible in conscious dogs.Study design
Blinded, crossover, experimental study.Animals
Six clinically healthy adult Beagle dogs.Methods
The nerves of the brachial plexus of the right thoracic limb were blocked under ultrasound guidance (UNB) in conscious dogs and under electrostimulation guidance (ENB) in anesthetized dogs with bupivacaine (0.4 mL kg–1, 0.25%). Saline (0.4 mL kg–1) was injected in control animals. Sensory nerve blockade was evaluated by scoring cutaneous sensation in targeted nerves. Motor nerve blockade was evaluated based on weight bearing, conscious proprioception and withdrawal reflex scores. Times to execute the technique in UNB and ENB were compared using t tests (p < 0.05). Scores for sensory and motor nerve blockades in each treatment were compared with scores before treatment and with control treatment scores using nonparametric repeated-measures two-way analysis of variance. Time to onset and duration of sensory nerve block were assessed using scores for four sensory nerve functions. A successful sensory nerve block was defined by decreases in scores for these functions. Success rates of nerve blocks were compared among treatments using McNemar’s test.Results
In UNB and ENB, onset times of sensory nerve blocks were 1 hour and 1.5 hours, respectively. Onset times of motor nerve blocks were 0.5 hour in both treatments. In UNB and ENB, durations of sensory nerve block were 3 hours and 0.5 hour, respectively, and durations of motor nerve block were 7.5 hours and 6.5 hours, respectively. Success rates did not differ between the techniques.Conclusions and clinical relevance
The UNB brachial plexus block had a shorter onset time and longer duration than ENB. UNB can be performed in conscious dogs or those under mild sedation. 相似文献108.
Effects of oral exposure of bisphenol A on mRNA expression of nuclear receptors in murine placentae assessed by DNA microarray 总被引:1,自引:0,他引:1
Imanishi S Manabe N Nishizawa H Morita M Sugimoto M Iwahori M Miyamoto H 《The Journal of reproduction and development》2003,49(4):329-336
Bisphenol A (BPA), a candidate endocrine disruptor (ED), is considered to bind to estrogen receptors and to regulate expressions of estrogen responsive genes. It has also shown evidence of affecting the reproductive, immunological and nervous systems of mammalian embryos. However, the effects of BPA on placentae, a central organ of feto-maternal interlocution, are still unclear. To reveal the mechanisms of BPA effects on placentae in mammals, we compared the mRNA expression of 20 nuclear receptors between placentae of vehicle controls and those of orally BPA exposed pregnant mice by a DNA microarray technique. In murine placentae, mRNAs of 11 nuclear receptors were not detected. However, greater than 1.5 fold changes in mRNA expression of nine nuclear receptors between vehicle control and BPA treated mice were noted. Moreover, remarkable changes in mRNA expression of six non-nuclear receptor proteins were induced by BPA exposure. There were various differences in the effects of BPA on the expression of these mRNAs between the placentae with male embryos and those with female embryos. Such embryo-sex dependent differences are interesting and important pointers to understanding of the endocrine disrupting effect of BPA. The present data indicate that BPA affects the expression of nuclear receptor mRNAs in placentae and may disrupt the physiological functions of placentae. 相似文献
109.
Nishiwaki H Nakagawa Y Kuwamura M Sato K Akamatsu M Matsuda K Komai K Miyagawa H 《Pest management science》2003,59(9):1023-1030
The electrophysiological actions of various neonicotinoids, including substituted benzyl derivatives, against recombinant Drosophila SAD/chicken beta2 hybrid nicotinic acetylcholine receptor (nAChR) were measured to analyze the relationships between the in vivo (insecticidal) and in vitro (binding and agonist) activities. Most of the neonicotinoids tested were capable of inducing inward currents by activating the hybrid nAChRs expressed in Xenopus laevis oocytes, whereas some compounds had no agonist activity and only blocked the acetylcholine-induced currents. Variations in the agonist activity were well correlated with those in the binding potency evaluated using [3H]imidacloprid as well as insecticidal activities. 相似文献
110.
Takaaki Fujimoto Hisashi Akutsu Miki Nei Kazuhito Kita Makoto Kuromaru Kazuyuki Oda 《Journal of Forest Research》2006,11(5):343-349
Genetic parameters for wood stiffness and strength properties were estimated in a 29-year-old hybrid larch stand (Larix gmelinii var. japonica × Larix kaempferi). The study included 19 full-sib larch families from Hokkaido, northern Japan. Implications of these genetic parameters in
wood quality improvement are subsequently discussed. Traits included in the analyses were the dynamic modulus of elasticity
of green logs (E
log), the modulus of elasticity (MOE), the modulus of rupture (MOR), compression strength parallel to the grain (CS) in small
clear specimens, wood density (DEN), and diameter at breast height (DBH). DEN had the lowest coefficients of variation and
MOE the highest. The narrow-sense heritability estimates of E
log, MOE, MOR, and CS were 0.61, 0.44, 0.60, and 0.43, respectively, and those of DEN and all mechanical properties increased
from an inner to outer position within the stem. E
log and DEN had high positive phenotypic (0.52–0.83) and genetic (0.70–0.92) correlations with MOE, MOR, and CS. The mechanical
properties of the inner position of the stem had rather high phenotypic and genetic correlations with those of the outer position
and overall mean. The predicted gains in wood stiffness (E
log and MOE) were higher than those of the strength properties (MOR and CS). The predicted correlated responses in MOE, MOR,
and CS when selecting for E
log and DEN were 72.6%–97.8% of a gain achievable from direct selection of these traits. DBH showed an insignificant correlation
with all mechanical properties, although selection of this trait had a slightly negative effect on the mechanical properties. 相似文献