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31.
The properties of ishikurage (Nostoc commune) and other algae were compared. Ishikurage and suizenji nori (Aphanothece sacrum) absorbed much more amaranth than others. They have a high settling volume (SV) in water. The high SV of ishikurage is attributable to its neutral detergent fiber (NDF). The acid detergent fiber (ADF) from the alga had a high amaranth absorption. However the absorption by the ADF did not explain the absorption by ishikurage.The results suggest that ishikurage may have a nutritional significance as a source of dietary fiber.  相似文献   
32.
Soybean (Glycine max L. Merr.) cvs. Akisengoku and Peking, and cowpea (Vigna unguiculata Walp.) cv. Kegonnotaki were inoculated with Bradyrhizobium japonicum AlO17, Shinorhizobium fredii USDAI93, and B. sp. Vigna MAFF03-03063, respectively and were cultured hydroponically with supply of CO2-free air, 3dm3 m-3 CO2 air, or 25 dm3 m-3 CO2 air to study the effects of the CO2 concentration in the rhizosphere on plant growth, nodulation, and nitrogen fixation. Increase of the CO2 concentration in the rhizosphere led to the increase of the plant dry weight in the symbiosis between Peking and USDAI93, and that between Kegonnotaki and MAFF03-03063. On the other hand, dry matter accumulation in the symbiosis between Akisengoku and AI017 decreased under the supply of 25 dm3 m-3 CO2 air aimed at increasing the CO2 concentration in the rhizosphere beyond the optimum CO2 concentration for growth. Nodule mass and nodule number per plant were highest in Akisengoku, followed by Kegonnotaki and lowest in Peking. Also the increase of the CO2 concentration in the rhizosphere led to the increase of the nodule mass and number in Kegonnotaki, while no changes were observed in Akisengoku and Peking. Biological nitrogen fixation (BNF) was highest in Akisengoku, followed by Kegonnotaki, and lowest or near zero in Peking. BNF in Akisengoku and Kegonnotaki showed a similar tendency to that of dry matter accumulation. BNF of Peking was especially low under the supply of CO2-free air, and it increased with the increase of the CO2 concentration in the rhizosphere. For the symbiosis of Bradyrhizobium strains with soybean and cowpea, the most suitable CO2 concentration for N2 fixation and plant growth was estimated to be about 10 dm3 m-3, while for the symbiosis of S. fredii with soybean, the value was estimated to be above 30 dm3 m-3.  相似文献   
33.
Cortisol (Cr), the most important glucocorticoid (GC), is well known to suppress uterine prostaglandin F2α (PGF) production. However, the details of the regulatory mechanisms controlling the cyclic changes in endometrial PGF production remain unclear. Here we investigated the expression of the GC receptor (GC-Rα), the actions of cortisol throughout the estrous cycle and the regulatory mechanism of GC-Rα in the bovine endometrium. The levels of GC-Rα protein were greater at the mid-luteal stage (Days 8–12) than at the other stages. Cr more strongly suppressed PGF production at the mid-luteal stage than at the follicular stage. GC-Rα expression was increased by progesterone (P4) but decreased by estradiol-17β (E2) in cultured endometrial stromal cells. The overall results suggest that ovarian steroid hormones control the cyclic changes in endometrial PGF production by regulating GC-Rα expression in bovine endometrial stromal cells.  相似文献   
34.
The effects of rearing temperature (23–29 °C) during the larval and juvenile stage on survival, growth and skeletal malformations in the seven-band grouper Epinephelus septemfasciatus were investigated. The survival rate of juveniles 30–40 mm in total length emerging from eggs was higher at 25 and 26 °C (0.1–1.3 %) than at 23 °C or 27–29 °C (0.004–1.5 %). Growth (increase in total length) was accelerated at higher temperatures. The frequency of malformed individuals was lower at 25–27 °C (36.0–61.5 %) than at 23, 28 or 29 °C (65.3–76.9 %). Specific incidences of spinal curvature and centrum fusion or defects in juveniles were not related to rearing temperature. However, incidences of twisted or compressed vertebrae (6.5–64.0 %) were higher at higher temperatures, while the incidence of bifurcated neural spine was significantly higher at 23 °C (43.6–54.4 %) than at other temperatures (3.3–22.7 %). The incidence rate of spinal curvature (23.3 %) was significantly higher in juveniles with a deflated swim bladder, regardless of rearing temperature. The results of this study suggest that the optimum culture temperature for seven-band grouper is 25–26 °C, collectively considering the survival, growth and incidences of abnormalities. Our results also demonstrate the significance of identifying the conditions for swim bladder inflation to prevent spinal curvature in seven-band grouper.  相似文献   
35.
In this study, fecal Escherichia coli isolates (n=188) from 34 dog-owner pairs and 26 healthy control humans (2 isolates per individual) were tested for susceptibility to 6 antimicrobials and screened for virulence genes. Genetic diversity between canine and owner isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Canine isolates exhibited significantly different rates of resistance to four and two antimicrobials, compared to control and owner isolates, respectively. Of the genes examined, the prevalence of sfa, hly, and cnf genes in canine isolates were higher than in control isolates, but not than in owner isolates. These results suggest that characteristics of owner isolates are somewhat similar to canine isolates, compared to isolates from non-dog owners. In addition, PFGE analysis revealed that transfer of E. coli between owners and their dogs had occurred within 3/34 (8.8%) households. Considering the effects of dog ownership on the population of E. coli isolates from owners, further epidemiological studies are required.  相似文献   
36.
The present study aimed to assess the effect of polymorphisms in the tumor necrosis factor α (TNF-α) promoter (A/A, A/G and G/G) and exons (T/T, T/C and C/C) on immune function and reproductive performance in dairy cows. The occurrence of the first postpartum ovulation within 3 weeks in the cows with the TNF-α promoter A/G and G/G genotypes was higher than in the A/A group. Among the different TNF-α exon genotypes, the occurrence of early first postpartum ovulation was higher in the T/C and C/C genotype groups than in the T/T group. Single nucleotide polymorphisms (SNPs) in the TNF-α gene did not affect the rate of artificial insemination (AI) or duration from parturition to next conception (days open). The apoptosis rate of polymorphonuclear leukocytes (PMNs) did not differ among the TNF-α promoter genotypes, but the PMN transmigration rate was significantly higher for the A/A and A/G genotypes than for the G/G genotype. Interleukin 8 (IL-8) mRNA expression in PMNs and peripheral blood mononuclear cells (PBMCs) before culture was significantly higher for the A/A genotype compared with the G/G genotype. There were no significant differences between the genotypes in the mRNA expression of TNF-α, IL-6, IL-1β, and toll-like receptor 4 (TLR4) in PMNs and PBMCs before and 4 h after culture. IL-8 and IL-1β production by PBMCs cultured for 4 h was significantly higher for the animals with the A/A genotype than for those with the G/G genotype. On the other hand, no significant difference was observed in IL-8 and IL-1β production by PMNs among different TNF-α genotypes. Taken together, these results suggest that SNP in the TNF-α gene affects immune function and reproductive performance in dairy cows.  相似文献   
37.
Uptake and transformation of 14C-labeled metabolites from several pesticides, 3-methyl-4-nitrophenol (1), 3,5-dichloroaniline (2), 3-phenoxybenzoic acid (3), (R,S)-2-(4-chlorophenyl)-3-methylbutanoic acid (4), and (1RS)-trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (5), were examined by using duckweed (Lemna gibba) in Hoagland's medium. More uptake into duckweed from the exposure water at pH 7.0 was observed for non-ionized 1 and 2 than for 3-5 in an ionized form, and their hydrophobicity accounted for these differences. While carboxylic acids 4 and 5 were scarcely transformed in duckweed, 1-3 mainly underwent phase II conjugation with glucose for 1 and 2, malic acid for 3, glutamic acid for 2, and malonylglucose for 3, the chemical identities of which were confirmed by various spectrometric analyses (LC-MS, LC-MS/MS, and NMR) and/or HPLC cochromatography with reference synthetic standards.  相似文献   
38.
Five monoclonal antibodies (OVA-01, -02, -03, -04, -06) produced against irradiated ovalbumin were investigated in relation to the conformational change in the ovalbumin molecule induced by irradiation with Cobalt-60 gamma-rays. Four antibodies (OVA-01, -02, -04, -06) recognized both native and irradiated ovalbumin, but OVA-03 reacted only with irradiated ovalbumin. These antibodies were classified by modified competitive ELISA, and their K(d) values were determined by the Klotz equation. Epitope analyses were also performed on OVA-03 using CNBr-cleaved peptide fragments from ovalbumin, and it was confirmed that OVA-03 bound to the fragment corresponding to residues Val173-Met196 of the ovalbumin molecule that consists of internal beta-sheet strand 3A and helix F1 containing one open turn. These results demonstrate that dramatic conformational changes in proteins can be induced or that some tertiary or secondary structures can be broken down by gamma-ray irradiation, producing new antigenic sites.  相似文献   
39.
We measured the natural stable carbon (C) and nitrogen (N) isotope ratio patterns of collembola and the organic substrates of their habitats and potential food sources in a warm temperate coniferous forest. Based on previous studies, we classified collembola into successional classes along litter decomposition gradients: early colonizers, late colonizers, and dominants-throughout. The stable C and N isotope ratios of late colonizers exceeded those of early colonizers, and those of the dominants-throughout were intermediate between early and late colonizers, which is consistent with previous studies on two macro-invertebrates, earthworms and termites. The C and N isotopic signature differences in collembola may reflect food resource partitioning along decomposition gradients.  相似文献   
40.
The metabolism of (14)C-labeled fenitrothion (Sumithion, [O,O-dimethyl-O-(3-methyl-4-nitrophenyl)phosphorothioate]) in tomato plant (Lycopersicon esculentum Mill., cv. Ponderosa) grown in the greenhouse equipped with quartz glass was conducted to investigate the effect of sunlight on the behavior of fenitrothion and to elucidate the detailed structure of conjugated metabolites. Tomato plants (BBCH 85) were topically treated with (14)C-labeled fenitrothion twice with a 2 week interval between applications. At 15 days after the second application, more than half of the recovered (14)C was detected as unaltered fenitrothion, glucose, and cellobiose esters of 3-methyl-4-nitrophenol (NMC) in extracts from tomato fruit. The photoinduced formation of the S-methyl isomer of fenitrothion via thiono-thiolo rearrangement was detected only in the surface rinse but at trace amounts. In the whole tomato fruit, fenitrothion, the S isomer, NMC-beta-glucoside, and NMC cellobioside were detected at 34.16, 1.28, 7.47, and 15.07% of the recovered (14)C, respectively. Trace amounts of the oxon analogue of fenitrothion were detected only on tomato leaves. The chemical structure of the cellobiose conjugate of NMC, 1-O-beta-d-glucopyranosyl-(1-->4)-beta-d-glucopyranosyl-3-methyl-4-nitrophenol, was determined by spectroscopic analyses (liquid chromatography-mass spectrometry, NMR), using the metabolite obtained from leaves and stems of tomato plant hydroponically grown with (14)C-labeled NMC.  相似文献   
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