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101.
Different leaching media composed of watersoluble extracts from Sakhalin fi r, Japanese cedar, and Japanese larch heartwoods and of taxifolin were used to characterize leaching of the C12 and C14 homologues of benzalkonium chloride from treated wood. The leaching medium of Sakhalin fi r extract moderately accelerated the leaching rates of the two homologues. Japanese cedar extract accelerated the leaching of the C12 homologue at a similar rate and that of the C14 homologue at a higher rate. Japanese larch extract remarkably accelerated the leaching rates of both homologues, particularly that of the C14 homologue. Thus, the leaching rate of the C14 homologue was higher than that of the C12 homologue with the Japanese cedar and larch extracts. The media of taxifolin, a major phenolic extractive of Japanese larch, preferentially accelerated the leaching rate of the C14 homologue. The amounts of phenolic compounds in the different leaching media were in the following order: Japanese larch > Japanese cedar > Sakhalin fi r. These results indicate a relationship between the amount of phenolic compounds and the leaching rates of the two homologues.  相似文献   
102.
The manner in which the bacterium Pseudomonas savastanoi pv. savastanoi ( Pss ), the causal agent of knot disease, infects olive plants is erratic and has not been fully documented. To investigate the process of Pss invasion, olive explants were inoculated in vitro and examined visually and by light microscopy at 2-weekly intervals for 10 weeks. In all host genotypes tested, interaction with the pathogen resulted in: (i) a progressive collapse of the stem, originating at the inoculation site at the apex of the explant, and proceeding downwards; and (ii), localized outgrowths on the stem located at various distances from the inoculation site. Histological analysis revealed that the anatomy of the outgrowths closely resembled that of knots formed in vivo ; they showed that Ps. savastanoi also diffused within the olive explants through the xylem vessels, and that the olive host reacted to pathogen invasion, possibly by producing substances of polysaccharidic and/or phenolic nature.  相似文献   
103.
The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN).  相似文献   
104.
The effects of autoclave and oven treatments on the gelatinization of rice flour and on the rheological characteristics of its pastes were studied by differential scanning calorimetry (DSC), rapid viscoanalysis (RVA), and rotational viscometry. Flours from autoclave‐treated rice (ATR) and oven‐treated rice (OTR) were prepared, respectively, by heating at 120°C for 60 min and 160°C for 60 min followed by drying (ATR sample), and grinding at 2.2–12.9% moisture content. The rice flour dispersions were adjusted between pH 6.3 and 2.8 using 0.2M citrate buffer. The retort processing of rice flour in water pastes were done at 120°C for 20 min either once or twice. The gelatinization peak temperature (PT and To) and the peak temperature corresponding to the amylose‐lipid complexes (Tp3) of ATR increased at pH 6.3 and 2.8 compared with OTR and UTR flour. This indicates that the internal structures of the starch granules in ATR became more stable to heat and acid, even though the damaged starch content of ATR was 23% compared with 16 and 7%, respectively, for untreated rice flour (UTR) and OTR. The OTR flour pastes showed a gel‐like behavior at pH 4.5 after retort processing in water at 120°C for 20 min; however, the ATR mixture behaved more like a liquid paste. Decreases in the reducing sugar content of OTR and ATR pastes suggested that enzymes in the heat‐treated rice were denatured, which retarded the hydrolysis of glucose chains and the rupture of starch granules during pasting.  相似文献   
105.
Precipitation chemistry in Japan was discussed on a wet-only sample database obtained in a nationwide survey from April 1989 to March 1993. Wet-only samples were collected at 29 stations over Japan on a biweekly basis. Commonly determined chemical parameters were measured in laboratories. The volume-weighted annual mean pH at each site ranged from 4.50 to 5.83 with a mean of 4.76. Concentration ranges and means (parenthesized) on an equivalent basis for major ions were as follows: nss-SO4 2–; 5.2–58.9 (38.6), NO3 ; 1.8–25.0 (14.1), NH4 +; 0.55–29.8 (18.3), nss-Ca2+; 2.0–34.5(14.2), Na+; 6.4–275.3 (49.1), Cl; 13.7–322.4 (63.5) eq L–1. Acid-base relationships for Phase-II records were quantitatively discussed in terms of three measures: pH, fractional acidity, and our proposed pAi.  相似文献   
106.
Abstract: A 15‐month‐old castrated male dog with a history of intermittent epistaxis and sneezing was admitted for the examination of a maxillofacial mass. An impression smear of a biopsy sample from the cauliflower‐shaped gingival mass contained numerous round cells, 5–25 μm in diameter, which contained a moderate amount of clear to pale blue cytoplasm and resembled lymphoid cells. Mitotic figures were frequently observed. The mass was diagnosed as malignant round cell neoplasia. On histologic examination the tumor was composed of diffusely arranged, small, atypical round cells with a small amount of fibrovascular stroma. Immunohistochemically, the cells were negative for CD3, CD18, CD20, CD79α, cytokeratin, melan‐A, chromogranin A, α‐smooth muscle actin, and myoglobin but positive for vimentin and desmin. The cells also had strong positive nuclear staining for myogenin and MyoD1. A diagnosis of solid‐pattern alveolar rhabdomyosarcoma was made on the basis of morphologic and immunohistochemical results. Alveolar rhabdomyosarcoma should be considered in the differential diagnosis of tumors in juvenile dogs, especially when cytologic findings reveal round, undifferentiated cells.  相似文献   
107.
In fish culture, cannibalism, which induces critical damage, is separated into two types: type I, which occurs in early larval stages when size heterogeneity is low; and type II, which starts in later larval and/or early juvenile stages following type I when size heterogeneity is high. In type II, the cannibal's maximum prey size is limited by its gape size relative to the prey fish body size. Ratios of prey to cannibal body size changes are associated with allometric factors and feeding behaviour with growth. In a previous study on grouper, the maximal prey size was estimated morphologically (i.e., the relationship between gape size and body height). This method is very simple and useful; however, it does not consider allometric factors and feeding behaviour changes; therefore, it probably causes a large estimation error. To overcome this, we present a new method for estimating maximal prey size to determine the size ranges for size grading of longtooth grouper, Epinephelus bruneus, juveniles using predation experiments. It is shown that grouper type II cannibalism is affected by two factors; in early juvenile stages by morphology and in later (TL over 50 mm) by prey size selectivity.  相似文献   
108.
109.
We examined the influence of nursery soil cover on germination of Thujopsis dolabrata var. hondai. Seeds were sown under seeding bed conditions: (1) nursery soil (andosol) without soil cover, (2) Kanuma pumice without soil cover, (3) nursery soil with nursery soil cover, and (4) nursery soil with sterilized sand cover. Germination percentages were compared between these conditions. The germination percentage (8.8%) at 10 weeks after sowing under condition 3 was significantly lower than under conditions 1, 2, and 4 (56.8%, 52.0%, and 47.2%, respectively). Of the nongerminated seeds under condition 3, 75.0% were decayed and several fungi were isolated from decayed seeds. An inoculation test of isolated fungi Cylindrocarpon tenue, Cylindrocarpon sp., Fusarium oxysporum, and Botrytis sp. to seeds showed that these fungi caused seed decay. Our results indicated that nursery soil cover may not be suitable for T. dolabrata var. hondai seeds sown in nursery soil because of seed decay by pathogens.  相似文献   
110.
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