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21.
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   
22.
Prebiotic fructooligosaccharides are noted for their intestinal immunodulating effects, and the identification of markers for the effects is a matter of great concern. This study aimed to identify marker genes for physiological effects of a particular fructooligosaccharide (FOS) on a host animal and also to define the target of its function in the small intestine. DNA microarray technology was used to screen candidate marker genes, and comprehensive changes in gene expressions in the ileum of mice fed with FOS were investigated. One of the major physiological effects of FOS was intestinal immunomodulation. Marker genes were then identified for major histocompatibility complex classes I and II, interferon, and phosphatidylinositol metabolites. Also, the ileum was segmented into Peyer's patch (PP) and the other ileal organ (DeltaPP), and these were analyzed by quantitative RT-PCR method, with the result that the site for recognizing the FOS function was the DeltaPP rather than the PP. This is the first paper showing the markers for the physiological effects of FOS in the small intestine at gene expression level. Applying these marker genes would make it possible to clarify the mechanisms of how the administration of dietary FOS and associated changes in the intestinal environment are recognized by host organisms as well as how its immunomodulating effects are expressed in the body.  相似文献   
23.
The effect of verbena as a trap crop on the occurrence of western flower thrips, Frankliniella occidentalis, and the incidence of Tomato spotted wilt virus (TSWV) in chrysanthemums were investigated. Verbena cvs. Pink Parfait and/or Fancy Parfait were cultivated alongside chrysanthemum cv. Jimba in a greenhouse in the proportion of 17%–25% of the chrysanthemum plants. Verbena plants attracted vector thrips, reducing western flower thrips colonization of chrysanthemum until flower bud initiation, and markedly suppressing TSWV incidence on chrysanthemums until flowering. Significant quantities of linalool oxide pyran were produced by the flower of cv. Fancy Parfait; and the ratio of cis-linalool oxide pyran, an attractant for vector thrips, to the trans-type was approximately 1 : 5. Our results suggest that cultivation of verbena as a trap crop may be useful in integrated pest management programs as a control for thrips-transmitted TSWV in chrysanthemums.  相似文献   
24.
The effect of a single oral administration of proanthocyanidins, oligomeric and polymeric polyhydroxyflavan-3-ol units, on the antioxidative potential of blood plasma was studied in rats. Proanthocyanidin-rich extract from grape seeds was administered by intragastric intubation to fasted rats at 250 mg/kg of body weight. The plasma obtained from water- or proanthocyanidin-administered rats was oxidized by incubation with copper sulfate or 2, 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) at 37 degrees C, and the formation of cholesteryl ester hydroperoxides (CE-OOH) was followed. The plasma obtained from proanthocyanidin-administered rats was significantly more resistant against both copper ion-induced and AAPH-induced formation of CE-OOH than that from control rats. The lag phase in the copper ion-induced oxidation of rat plasma was remarkably increased at 15 min after administration of proanthocyanidins and reached a maximum level at 30 min. When the plasma from proanthocyanidin-administered rat was hydrolyzed by sulfatase and beta-glucuronidase following analysis by high-performance liquid chromatography with electrochemical detection, metabolites of proanthocyanidins occurred in rat plasma at 15 min after administration, three peaks of which were identified as gallic acid, (+)-catechin, and (-)-epicatechin. These results suggest that the intake of proanthocyanidins, the major polyphenols in red wine, increases the resistance of blood plasma against oxidative stress and may contribute to physiological functions of plant food including wine through their in vivo antioxidative ability.  相似文献   
25.
Yamaguchi  Hitomi  Koga  Nozomi  Ichimi  Kazuhiko  Tada  Kuninao 《Fisheries Science》2020,86(6):1067-1078
Fisheries Science - We examined phytoplankton productivity in Shido Bay, an active oyster farming area in the eastern Seto Inland Sea, Japan, by an in situ 13C method from March 2016 to January...  相似文献   
26.
Comparison of the QT interval and corrected QT interval values that were calculated by the methods of Bazett (QTc1) and Fridericia (QTc2) were made between dogs with or without cardiac diseases to determine the influence of the QT interval on canine heart failure. Upon comparison of the measured values on ECG between the cardiac disease and non-cardiac disease groups, it was observed that the heart rate(HR) was significantly higher in the cardiac disease group than in the non-cardiac disease group, although the QT interval was similar in the two groups. The QTc1 and QTc2 were significantly longer in the cardiac disease group than in the non-cardiac disease group. With the progression of the New York Heart Association Class, the HR tended to increase. The QTc1 and QTc2 became significantly prolonged with the progression of heart failure. Nevertheless, because Bazett's correction formula is known to overcorrect when the HR is high, it was considered that the QTc1 was actually overcorrected by high HR with the progression of heart failure. The QTc2, on the other hand, was only slightly influenced by HR, suggesting that the prolongation was due to the progression of heart failure. These results suggest that the prolongation of QTc2 in cardiac disease reflects the substantial prolongation of the QT interval without the influence of HR. It is suggested that the QTc2 could be a useful parameter for assessing the degree of heart failure in dogs with cardiac disease.  相似文献   
27.
ABSTRACT In the rice blast fungus pathosystem, cerebroside, a compound categorized as a sphingolipid, was found in our previous study to be a non-racespecific elicitor, which elicits defense responses in rice. Here we describe that cerebroside C is produced in diverse strains of Fusarium oxysporum, a common soilborne agent of wilt disease affecting a wide range of plant species. In addition, some type of cerebroside elicitor involving cerebroside A, B, or C was detected in other soilborne phytopathogens, such as Pythium and Botrytis. Treatment of lettuce (Lactuca sativa), tomato (Lycopersicon esculentum), melon (Cucumis melo), and sweet potato (Ipomoea batatas) with cerebroside B resulted in resistance to infection by each pathogenic strain of F. oxysporum. Induction of pathogenesis-related genes and H(2)O(2) production by treatment with cerebroside B were observed in tomato root tissues. The cerebroside elicitor showed no antifungal activity against F. oxysporum in vitro, indicating that the cerebroside elicitor activates defense mechanisms to confer resistance to Fusarium disease. These results suggest that cerebroside functions as a non-race-specific elicitor in a wide range of plant-phytopathogenic fungus interactions. Additionally, cerebroside elicitor serves as a potential biologically derived control agent.  相似文献   
28.
To elucidate the water-conducting pathways in living trees by the dye injection method, suitable sample preparation procedures are needed. We evaluated quantitatively the properties and concentrations of three dyes (acid fuchsin, basic fuchsin and safranin) widely used for this purpose, and determined the optimal conditions required to avoid artifacts after dye injection into the sap stream of Pieris japonica D. Don. Among the dyes tested, an aqueous solution of acid fuchsin at a concentration of 0.1% or more was the most useful for delineating water movement. In non-transpiring stem segments, the vertical movement of acid fuchsin by capillarity and diffusion from the dye injection site was limited. However, acid fuchsin moved rapidly in the horizontal direction by capillarity and diffusion, and most xylem cells were stained within 2 h. A delay of more than 2 h between dye injection and examination of the tissues greatly reduces the precision of the method. Use of the dye injection method without appropriate, well-defined experimental procedures may give rise to misleading information about the functional water-conducting pathway in living trees.  相似文献   
29.
Indole acetic acid (IAA) was believed to be an important regulator in xylem formation in conifers. However, few studies have been done on the endogenous amount of IAA in cambial region tissues in sugi (Cryptomeria japonica) trees. In this study, we report the IAA amounts in the lower and upper trunk of mature sugi cultivars (Kumotoshi, Yaichi and Obiaka) in September, and the effects of growth traits on the IAA amounts. The effect of height position (lower or upper trunk) on IAA amounts was found to be larger than that of genetic variation (Kumotoshi, Yaichi or Obiaka) by two-way ANOVA. There was no significant interaction effect (genetic variation × height position). The IAA amounts of all trees varied from 3 to 42 ng/cm2 at the lower trunk and 9 to 47 ng/cm2 at the upper trunk. Crown length and distance from crown base had significant positive and negative effects on IAA amounts in the trunk of sugi cultivars, respectively. Distance from crown base had a larger effect on IAA amounts than crown length. In Yaichi, taller trees had larger IAA amounts at both the lower and upper trunk.  相似文献   
30.
The superior capability of cognitive experts largely depends on quick automatic processes. To reveal their neural bases, we used functional magnetic resonance imaging to study brain activity of professional and amateur players in a board game named shogi. We found two activations specific to professionals: one in the precuneus of the parietal lobe during perception of board patterns, and the other in the caudate nucleus of the basal ganglia during quick generation of the best next move. Activities at these two sites covaried in relevant tasks. These results suggest that the precuneus-caudate circuit implements the automatic, yet complicated, processes of board-pattern perception and next-move generation in board game experts.  相似文献   
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