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181.
Cryptosporidium species have been found in more than 150 species of mammals, but there has been no report in raccoon dogs. Here we found the Cryptosporidium organism in a raccoon dog, Nyctereutes procyonoides viverrinus, and identified this isolate using PCR-based diagnostic methods. Cryptosporidium diagnostic fragments of the 18S ribosomal RNA, Cryptosporidium oocyst wall protein and 70-kDa heat shock protein genes were amplified from the isolate and sequenced to reveal the phylogenetic relationships between it and other Cryptosporidium species or genotypes reported previously. The results showed that the raccoon dog isolate represented the C. parvum cattle genotype which could be a causative agent in human cryptosporidiosis.  相似文献   
182.
Test samples of Japanese larch (Larix leptolepis) heartwood and Japanese beech (Fagus crenata) sapwood were heated for 22 h at constant temperatures (50°–180°C) under three water content conditions. Raman spectra of the samples were recorded before and after the heat treatments, and spectral changes in the range from 1000 cm−1 to 1800 cm−1 were evaluated using the difference spectrum method. For both wood species, the Raman band intensity at 1655–1660 cm−1 due mainly to the C=C and C=O groups in lignin clearly decreased with increasing heat-treatment temperature (HTT). The spectral change was thought to reflect the progress of condensation reactions of lignin molecules during the heat treatment. Moreover, the decrease in band intensity was considerably facilitated by the presence of water in the cell wall, suggesting that the condensation is closely related to the softening of lignin. From the spectral changes in the wavenumber region of 1200–1500 cm−1, it was considered that wood constituents are partially decomposed at the higher HTT. Part of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003  相似文献   
183.
The optimum environmental temperature for a biodegrading machine using wood particles as a matrix was investigated using a small-scale degradation reactor and model waste. The biodegradation rate was evaluated by weight loss of waste and CO2 evolution. The degradation reaction was restricted only by adjusting the environmental temperature while sufficient oxygen and substrates were supplied. Results suggested that the optimum temperature for degradation was 30°–40°C for exploiting biological activity effectively with the lowest use of energy. Bacteria from the environment propagated in the reactor with no inoculum added. The microbial flora changed during the operation time but had no effect on the biodegradation rate.Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1998  相似文献   
184.
Summary The present study was undertaken to reappraise the materials and methods used by various reports discussing Ashby's hypothesis on heterosis of physiological traits in maize. The review of 15 reports led to the conclusion that both Ashby's hypothesis and the subsequent refutations of the hypothesis were based on insufficient evidence. New experiments using suitable pollination techniques and an appropriate statistical analysis enabled us to confirm Ashby's hypothesis.This work is supported by the Green Energy Program' (GEP84-II-6-6) promoted by MAFF.  相似文献   
185.
Sterol ferulate, free sterol, and 5-alk(en)ylresorcinol constituents of wheat, rye, and corn bran oils were studied. Among the sterol ferulates, one novel compound, 24-methylenecholestanol ferulate (7), along with six known compounds, namely, 24-methylcholestanol ferulate (1), 24-methylcholesterol ferulate (2), 2-methyllathosterol ferulate (3), stigmastanol ferulate (4), sitosterol ferulate (5), and schottenol ferulate (6), were isolated and characterized. Five known free sterols, namely, 24-methylcholesterol (8), stigmastanol (9), sitosterol (10), schottenol (11), and stigmasterol (12), were isolated and identified. 5-Alk(en)ylresorcinols were found in wheat and rye bran oils but not in corn bran oil. Of these, one new compound, 5-n-(2'-oxo-14'-Z-heneicosenyl) resorcinol (19), and seven known compounds, namely, 5-n-heptadecyl- (13), 5-n-nonadecyl- (14), 5-n-heneicosyl- (15), 5-n-tricosyl- (16), 5-n-pentacosyl- (17), 5-n-(14'-Z-nonadecenyl)- (18), and 5-n-(2'-oxoheneicosyl)resorcinols (20), were isolated and characterized. These compounds were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, which is known to be a primary screening test for antitumor promoters. Four compounds, 1, 2, 4, and 11, showed potent inhibitory effects on EBV-EA induction.  相似文献   
186.
A method for the simultaneous determination of Sb and Bi in soils using an automated hydride generation system with an electrically heated quartz cell atomizer, and an atomic absorption spectrophotometer is described. Five g of the air-dried soil was placed in a 100 mL Erlenmyer flask fitted with a Liebig condenser and boiled gently with 20 mL 6 M HCl for 1 hr on a sand bath. The extract was then filtered into a 100 mL volumetric flask. The two elements in the sample solution (<30 mL) placed in a 50 mL volumetric flask are prereduced by potassium iodide and ascorbic acid solutions. Reduction of Sb and Bi ions to stibine and bismuthine is obtained by sodium tetrahydroborate solution. Detection limits (S/N = 2) are 7 ng g?1 dry soil for Sb and 0.7 ng g?1 dry soil for Bi. The effects of 19 diverse ions on the absorbances of Sb and Bi were investigasted, and it was found that the errors by these ions will be within 5% in the ordinary unpolluted or even polluted soils. In order to examine the accuracy of the proposed method, Sb and Bi in the four Canadian reference soils and NBS-4355 from the National Bureau of Standards in the USA were determined. The values obtained in this work are close to the recommended or the not-certified values. The amounts of Sb, Bi and the related elements in the soils near a smelter were also analyzed.  相似文献   
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189.
The Beaudette 42 strain of avian infectious bronchitis virus, Sato strain of Newcastle disease virus, and Uchida strain of avian reovirus were passaged in Chinese hamster lung cells (Don), and some properties were examined. The Don-passaged strains showed a difference in replication in Don and chicken embryo kidney cells in one-step growth curve examinations and a partial modification in pathogenicity to chicken embryos; nevertheless, neutralization tests revealed no serological alteration.  相似文献   
190.
The distribution of amyloid deposits was histopathologically and immunohistochemically examined in 25 cows aged 5 to 10 years that had been diagnosed with systemic AA amyloidosis. This examination revealed that amyloid deposits were also present in the hypophysis, ovary, uterus, mammary gland and skeletal muscle, in addition to the liver, kidney, spleen, pancreas, thyroid gland, adrenal gland, gastrointestinal mucosa, heart, lung and lymph nodes. The examined cows tended to have chronic inflammations, including chronic mastitis (six cases) or chronic pneumonia (four cases), which is thought of as a causative agent of AA amyloidosis. In contrast, five cases did not exhibit any chronic inflammation.  相似文献   
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