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161.
Epsilon-polylysine micro particles (SGEPL) and polyethyleneimine micro particles (SGPEI) were developed by the addition of a hydrophobic group and the immunological characterization of these micro particles and aluminum hydroxide (ALUM) was investigated. BALB/c mice were injected intraperitoneally with ovalbumin (OVA) as an antigen and SGEPL, SGPEI or ALUM as an adjuvant. The results showed that the mice injected with SGEPL produced a significant portion of anti-OVA antibody subclass IgG2a in the sera and suppressed interleukin (IL)-4 and IL-5, but enhanced IL-12 and interferon-gamma (IFN-gamma) from the spleen cells. Similar results relating to cytokines were also obtained, even without OVA. Direct stimulation with SGEPL to na?ve BALB/c mouse spleen cells induced IL-12 and IFN-gamma. Both spleen and purified B cells produced IgG1 and IgE after stimulation with IL-4 and the anti-CD40 monoclonal antibody. With the addition of SGEPL, the IgE production from the cells was suppressed as a result of enhanced IFN-gamma production. Furthermore, IgE production was also suppressed in the purified B cells without the influence of IFN-gamma or IL-12. Thus, we suggest SGEPL drives cytokine production to Th1 profile. It will be a novel promising adjuvant based on this viewpoint.  相似文献   
162.
Among the many mycotoxins, T-2 toxin, citrinin (CTN), patulin (PAT), aflatoxin B1 (AFB1) and ochratoxin A (OTA) are known to have the potential to induce dermal toxicity and/or tumorigenesis in rodent models. T-2 toxin, CTN, PAT and OTA induce apoptosis in mouse or rat skin. PAT, AFB1 and OTA have tumor initiating properties, and OTA is also a tumor promoter in mouse skin. This paper reviews the molecular mechanisms of dermal toxicity and tumorigenesis induced in rodent models by these mycotoxins especially from the viewpoint of oxidative stress-mediated pathways.  相似文献   
163.
ABSTRACT:   A feedback management procedure is proposed that is based on controlling the size of a Marine Protected Area (MPA): increasing the size of the MPA when the population is below a predetermined target level and reducing its size when it is above. The objective of fisheries management is to have the population size approximate the target level. Local stability was analyzed, to determine whether a population could remain close to the target level with small perturbations, using a generalized population dynamics model without including an age structure. The procedure was able to sustain the population at the target level if the target was set at a level that gives the maximum sustainable yield and if drastic changes in the MPA size were avoided. Global stability was analyzed numerically to determine whether a population would always approach the target level regardless of the present population size, using a specified model that allowed for temporal changes in the spatial distribution of a sedentary population. The procedure, which did not require direct control of catch quota or fishing effort, appeared to attain the objective successfully.  相似文献   
164.
ABSTRACT:   The search for dinucleotide repeat microsatellites within scaffolds 1–25 of genome database JGI Fugu v3.0 for the pufferfish Takifugu rubripes revealed that 80% of microsatellite loci consisted of five to 13-fold repeats with locus-specific differences in density. Eleven out of 15 microsatellite loci isolated from the database with which genotyping using wild pufferfish was successfully performed showed polymorphism; that is, the means of the number of alleles and expected and observed heterozygosities at these 11 loci were 21.8, 0.915 and 0.829, respectively. It was confirmed that eight out of the 11 polymorphic loci were inherited through the Mendelian law and one pair of microsatellite loci derived from the same scaffold was linked. These results demonstrated that these loci are useful for constructing a linkage map in the pufferfish as DNA markers.  相似文献   
165.
The self-feeding activity of the barfin flounder (Verasper moseri) was examined under natural photoperiod and temperature. The experiment, carried out over 12 weeks from September to December, involved tagged fish (mean body weight: 371 g) reared in three 1000-l tanks (3 or 5 fish per tank) with a self-feeder device. The sensor comprised a switch and trigger string with a bead. Self-feeding activity was recorded in all tanks from day 1. The fish fed mostly at night. Strong positive correlations were observed between the number of daily feeder activations and water temperature/photoperiod, and all fish grew during the experiment. These results demonstrate that barfin flounder can operate self-feeding systems and it is suggested that self-feeding activity is influenced by photoperiod and water temperature.  相似文献   
166.
The determination of damaged starch and diastatic activity in flour was studied using a flow-injection analysis (FIA) biosensor system. The system consisted of an oxygen electrode and an immobilized enzyme column containing purified glucoamylase and glucose oxidase immobilized on activated aminopropyl glass beads. The biosensor system has an optimum pH between 6.5 and 7.5 and an optimum temperature of 35°C for glucose measurement. The response of the FIA biosensor was linear up to 1.000 g/L of glucose with a lower detection limit of 0.025 g/L. Each assay took about 20 min, and the system showed good reproducibility (r = 0.998, n = 8). When applied to the measurement of damaged starch and diastatic activity in wheat flour, the results obtained agreed with those obtained using the conventional methods of measurement. This biosensor system is a rapid practical alternative for the measurement of damaged starch and diastatic activity in wheat flour.  相似文献   
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