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91.
Differences in the water adsorption properties of moso bamboo (Phyllostachys pubescens) were examined by analyzing the isotherms. Hygroscopicity decreased from the bottom to the top of the culm, and this tendency was marked above about 80% relative humidity. Results of alkali extraction and the analysis of bundle sheath distribution revealed that the distribution of hygroscopic saccharides, for example, hemicelluloses and less-hygroscopic vascular bundles, affects the hygroscopicity, which varies depending on the position of the internode.  相似文献   
92.
To investigate the changes in microstructures of wood with elapsed time in the environment, CO2 adsorption onto dry wood was measured at ice-water temperature (273 K) for samples aged from 0.1 years to over 1000 years. The micropore size distribution was obtained using the Horvath-Kawazoe method. Micropores smaller than 0.6 nm in wood decreased in number with elapsed time in the environment, and a negative correlation was found between cumulative pore volume for pores smaller than 0.6 nm and elapsed time in the environment. Cumulative pore volume in the 1000-year sample was almost half of that in the 0.1- year sample. Micropores smaller than 0.6 nm in wood with a few decades or more of elapsed time increased in number after rewetting and drying. Consequently, microstructures of wood with longer time elapsed in the environment were considered to be more stable, because of longer-term thermal motion and possibly more repeated moisture adsorption and desorption and/or temperature variation in the environment.  相似文献   
93.
In melon (Cucumis melo L.), the amount of fertile pollen decreases at low temperature during winter and early spring and thereby restricts fertilization. A promising way to overcome this problem is to develop parthenocarpic cultivars. Parthenocarpic cucumber and squash, but not melon cultivars are available. In this study, we explored 172 accessions from an East Asian melon collection and identified accessions that exhibited strong parthenocarpic ability throughout the year. Crosses between parthenocarpic accessions and a non-parthenocarpic cultivar, and among parthenocarpic accessions indicated that parthenocarpy may be inherited in a recessive manner and is likely controlled by the same gene or genes in these accessions. The parthenocarpic indices, such as the size and number of parthenocarpic fruits, differed among the cultivation periods, indicating the importance of environmental factors for parthenocarpic fruit development. We conclude that it is possible to breed new cultivars with stable parthenocarpic ability throughout the year by using the identified accessions.  相似文献   
94.
In this article, the conservation of seven archeological waterlogged woods (WW) with polyethylene glycol (PEG) 4000, trehalose, and feather keratin was investigated. The results showed that the dimensional stability of WWs significantly improved after the different treatments. The anti-shrink efficiency values of the WWs treated with keratin ranged between 72.5 and 96.2% depending on the species and degree of wood degradation. These values varied from 82.4 to 96.9% for the WWs treated with PEG or trehalose. Microscopic observations showed that the chemically-treated woods maintained their original cell structures, forms, and shapes. It was also revealed that the reinforcement of cell walls by the feather keratin treatment was different from those observed for the PEG or trehalose treatments. It was observed that PEG and trehalose primarily filled the wood voids, while keratin predominantly absorbed on the cell walls and middle lamellae. Based on the improved dimensional stability of wood, shortened impregnation time, removability of chemical, and esthetic results obtained from the treatment, keratin showed a good performance in average as a preservation agent.  相似文献   
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A cholesterol-free diet containing dried powder of Jew's mellow leaves, persimmon leaves or sweet potato leaves respectively at 5% level as dietary fiber was fed to male Sprague-Dawley rats for about one month. The experiment was conducted twice except for sweet potato leaves. In the groups fed the diet mixed with powders of any of the three different dried green leaves, the hepatic cholesterol concentration significantly decreased. Such lowering was not observed in serum cholesterol concentration compared with the control (cellulose) group. A significant increase in fecal weight was observed in all the groups fed the green leaf samples. All the dried green leaves increased fecal excretion of bile acids per gram or per day compared with the control group in both experiments, but only the dried Jew's mellow leaves showed an increased excretion of neutral sterols. These results suggest that lowering of hepatic cholesterol by powdered green leaves is not necessarily due to the same factor, but to the increased fecal excretion of bile acids due to inhibited enterohepatic circulation in animals given these samples.  相似文献   
97.
The optic tectum of Japanese quail embryos with in ovo exposure to methotrexate 100 ng/g egg on embryonic day 4 was examined from 3 to 24 hour after treatment. At 9 hour after methotrexate exposure, several apoptotic neuroepithelial cells appeared in the ventricular zone of the optic tectum; these increased in number and were diffusely distributed throughout all layers of the ventricular zone of the optic tectum at 12 hour. At 24 hour, neuroepithelial cells in the ventricular zone of the optic tectum were eliminated and showed sparse cell density. Throughout the experimental period, proliferation of neuroepithelial cells in the ventricular zone of the optic tectum of methotrexate-treated embryos was inhibited. These results suggest that neuroepithelial cells in the ventricular zone of the optic tectum in Japanese quail embryos can be affected by folic acid antimetabolites, methotrexate, at an early embryonic stage.  相似文献   
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A case of encephalitis in a Japanese monkey (Macaca fuscata) was examined histopathologically and serologically. The animal had brain lesions consisting of perivascular cuffs, malacia, inclusion bodies and giant cells. Monoclonal antibody to the nucleoprotein of canine distemper virus (CDV) stained the inclusions, and the distribution of the virus antigen was closely associated with that of the histological lesions. Serologically, all the 22 monkeys in the same group as the diseased monkey had relatively high titers of neutralizing antibody to CDV, but not to measles virus (MV). The pattern of the antibody titers to CDV and MV closely resembled that of cynomolgus monkeys experimentally inoculated with CDV, but differed from that of monkeys inoculated with MV. These findings suggest that an epidemic of CDV occurred in these Japanese monkeys, associated with one case of fatal viral encephalitis. This is believed to be the first report of a natural infection by CDV in non-human primates.  相似文献   
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