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71.
Nitrous oxide (N2O) is a greenhouse gas that contributes to the destruction of stratospheric ozone, and agricultural soil is an important source of N2O. Aerobic soils are sinks for atmospheric methane (CH4), a greenhouse gas. Ammonia monooxygenase (AMO) can oxidize CH4, but CH4 is mostly oxidized by methane monooxygenase (MMO), and CH4 oxidation by AMO is generally negligible in the soil. We monitored the N2O and CH4 fluxes after urea application in fields containing different soils using an automated sampling system to determine the effects of environmental and microbial factors on the N2O and CH4 fluxes. The soil types were Low-humic Andosol (Gleyic Haplic Andosol), yellow soil (Gleyic Haplic Alisol) and gray lowland soil (Entric Fluvisol). Cumulative N2O emissions from the yellow soil were higher than those from other soil types, although the difference was not significant. The CH4 uptake level by Andosol was one order of magnitude higher than that by other soils. There were significant relationships between the ammonia oxidation potential, AOB and AOA amoA copy numbers, and the CH4 uptake. In contrast, the gene copy numbers of methane-oxidizing bacteria (MOB) pmoA were below the detection limit. Our results suggested that the AMOs of AOB and AOA may have more important roles than those previously considered during CH4 oxidation in agricultural soils treated with N fertilizers.  相似文献   
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Prevalences of thermostable direct hemolysin (TDH)-producing strains in communities of a gastropod mollusc. Clithon retropictus, and a bivalve mollusc, Corbicula japonica, and levels of the strains in attached microalgae and muddy sediments were investigated at a brackish-water area along Hashizu Creek and Togo Pond in Japan, V. parahaemolyticus was detected from attached microalgae at Hashizu Creek in summer months with the highest level of 1.4 x 10(5) cfu/g. Levels of the organism among 20 animals of C. retropictus and C. japonica at the area varied betwen non-detectable level and 10(3) per mollusc in summer months. TDH was detected from culture supernatants of 11-16% of strains isolated from the algae, sediments and C. japonica and 28% of those isolated from C. retropictus at Hashizu Creek. These evidences suggest that C. retropictus would get TDH-positive strains from the algae.  相似文献   
74.
Blastocystis infection in amphibians was surveyed in three species of anuran and one species of urodele amphibians captured at two distinct locations in Japan. All three species of frogs were highly infected with Blastocystis, while 69 individual urodele newts, Cynopus pyrrhogaster, were negative for infection. Eleven Blastocystis isolates (47.8%) were recovered from 23 Rana nigromaculata leopard frogs. Twenty-three (92%) of 25 Rana catesbeiana bullfrogs and all (100%) of 24 Bufo japonicus japonicus toads were positive for Blastocystis. Two distinct populations of the toad and bullfrog showed a high prevalence (100 or 84.6%) of Blastocystis infection, while in two populations of the leopard frog only one population was positive for Blastocystis (84.6%). Three Blastocystis isolates from different species of the frogs were established. Since none of the three isolates could survive at 37 degrees C, a temperature tolerance assay was performed to assess the optimal growth temperature and to determine the range of non-lethal temperatures. During the exponential growth phase of 3- or 4-day cultures at 25 degrees C, three isolates were exposed to 4, 28, 31, or 34 degrees C for 3 days and then returned to 25 degrees C to monitor the cell growth. Based on the optimal growth temperatures and different ranges of temperature tolerance among the three new isolates from frogs and two known species, Blastocystis hominis and Blastocystis lapemi, it was established that the three isolates recovered from different species of frogs had different physiological features from B. hominis and B. lapemi.  相似文献   
75.
Automated ribotyping classified 70 Erysipelothrix species strains, previously classified into 14 RAPD patterns and into 63 PFGE patterns, into 27 ribogroups. Twenty-three strains of the 70 analyzed and classified into 13 ribogroups were previously classified into six ribotypes by the traditional ribotyping method. Moreover, automated ribotyping differentiated seven strains that were not differentiated by PFGE. Therefore, automated ribotyping was more sensitive than RAPD and traditional ribotyping, and it might be a useful method for a rapid screening in epidemiological study of strains of this genus, and more accurate results can be obtained when this method is used together with PFGE.  相似文献   
76.
In human and canine cancers, the inactivation of p53 protein as well as p53 gene mutation and MDM2 overexpression result in centrosome amplification that in turn contributes to chromosomal instability. To explore the usefulness of the detection of centrosome amplification as a surrogate marker of dysfunction in the p53 pathway, we systematically analysed centrosome amplification, p53 overexpression, p53 gene mutation and MDM2 overexpression in canine tumours. Centrosome amplification was detected in 16 of 51 (31%) naturally developing tumours in dogs. All the tumour specimens with aberrations in the p53 pathway, including p53 overexpression, p53 gene mutation or MDM2 overexpression, showed centrosome amplification, suggesting that the detection of centrosome amplification could serve as a preliminary surrogate marker of dysfunction in the p53 pathway.  相似文献   
77.
In the present study, we examined histochemically the tissue distribution of dextran sulfate sodium (DSS) in the acute phase of murine colitis induced by administering DSS in the drinking water. DSS was mainly observed in the Kupffer cells of the liver, in the macrophages of the mesenteric lymph node (MLN) and in the lamina propria of the large intestine after administration of DSS. We followed the time course of DSS distribution and found that DSS, which was considered as a large and negatively charged molecule that can not easily cross membranes, was distributed in the liver, the MLN, and the large intestine 1 day after the start of administration of DSS.  相似文献   
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Plant Foods for Human Nutrition - Our previous study showed anti-influenza virus activity in adlay tea prepared from adlay seeds, naked barley seeds, soybean, and cassia seeds. In this study, we...  相似文献   
80.
Cardiovascular disease (CVD) has emerged as an important cause of death in patients with systemic lupus erythematosus (SLE). Reduced adiponectin and elevated leptin levels may contribute to CVD in SLE patients. The purpose of this study was to verify the effects of fish oil (FO) on adiponectin and leptin in patients with SLE. Biochemical and disease activity analysis were performed. Patients with SLE were divided in two groups: patients who used fish oil for four months and patients who did not use fish oil. Patients with SLE who used FO had a significant decrease in SLE disease activity index (SLEDAI) score (p ˂ 0.023) in relation to baseline. SLE patients who used fish oil had increased adiponectin levels (p ˂ 0.026) and decreased leptin levels (p ˂ 0.024) compared to baseline values, whereas there were no differences in adiponectin and leptin levels in patients with SLE who did not use fish oil. In conclusion, the findings of increased serum adiponectin an decreased leptin levels after 120 days in the fish oil group, reinforce the importance of evaluating prospective studies of fish and fish oil fish ingestion on these adipokines in an attempt to decrease cardiovascular risk factors in patients with SLE.  相似文献   
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