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1.
In order to investigate the causative factors responsible for removal of mucous coat from the gill lamellae of young yellowtail, Seriola quinqueradiata by red tide, diazo-reactions were employed for planktons and their media. The concentration of NO2- in the medium containing the raphidophyceae, Chatonella antiqua (ca 2000 cells/ml), was 0.70 +/- 0.05 (mu g/ml +/- SEM). In addition, diazo-reaction positive substances (NOx) which may degenerate the mucous, was highly concentrated in the cortex (perikaryon) of Chattonella antiqua. Morphologically, mucocysts, and chloroplats were likewise present in the cortex. Mucocysts were packed with fine fibrous content. Histochemically, the mucocysts were stained with PAS and had an abundance of nitrogen oxides (NOx). We observed discharge of the fibrous material from the mucocysts. These results suggest that when Chattonella antiqua is passing between the gill lamellae, NOx discharged from the mucocysts may act on the mucous, leading to the degeneration and concomitant removal of the mucous coat from gill lamellae.  相似文献   
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Micronucleus tests of potassium bromate (KBrO3) and potassium chromate (K2CrO4) were conducted with peripheral blood reticulocytes (PB-RETs) of CD-1 male mice dose intraperitoneally. Peripheral blood cells collected from the tail were stained supravitally with acridine orange (AO) using AO-coated glass slides. Both KBrO3 and K2CrO4 induced micronuclei in PB-RETs in the same manner as in polychromatic erythrocytes of bone marrow.  相似文献   
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The peptide N-acetylmuramyl-l-alanyl-d-isoglutamine (MDP), which has adjuvant activities, and 17 of its derivatives and analogs were synthesized and assayed to elucidate the structure necessary for adjuvant activity in induction of experimental allergic encephalomyelitis (EAE) in guinea pigs. The results revealed the importance of the d configuration and the α-carboxamide group of the isoglutaminyl residue of MDP for adjuvant activity. Replacement of the l-alanyl residue of MDP by d-alanine, but not by l-serine or glycine, resulted in a marked decrease in the activity. The β-methyl glycoside of MDP was found to be more active than the α-methyl derivative. 6-O-Stearoyl-N-acetylmuramyl-l-alanyl-d-isoglutamme showed activity.  相似文献   
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Attempts were made to isolate and identify the unit chemical structure essential for manifestation of the immunoadjuvant activities characteristic of bacterial cell walls. The N-acetylmuramyl-peptide subunit monomers, Nalpha-(N-acetylmuramyl-L-alanyl-D-isoglutaminyl)-Nepsilon-(glycylglycyl)-L-lysyl-D-alanine from the cell walls of Staphylococcus aureus (FDA 209P) and N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelic acid and/or N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelyl-D-alanine from those of Lactobacillus plantarum (ATCC 8014), were shown to be unit chemical entities with definite adjuvant activity both in stimulation of antibody production and in induction of delayed-type hypersensitivity to ovalbumin when administered to guinea-pigs as water-in-oil emulsions.  相似文献   
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The adaptor protein-2 (AP-2) complex is a heterotetramer involved in clathrin-mediated endocytosis of cargo proteins from the plasma membrane in animal cells. The homologous genes of AP-2 subunits are present in the genomes of plants; however, their identities and roles in endocytic pathways are not clearly defined in plants. Here, we reveal the molecular composition of the AP-2 complex of Arabidopsis thaliana and its dynamics on the plasma membrane. We identified all of the α-, β-, σ-, and μ-subunits of the AP-2 complex and detected a weak interaction of the AP-2 complex with clathrin heavy chain. The μ-subunit protein fused to green fluorescent protein (AP2M-GFP) was localized to the plasma membrane and to the cytoplasm. Live-cell imaging using a variable-angle epifluorescence microscope revealed that AP2M-GFP transiently forms punctate structures on the plasma membrane. Homozygous ap2m mutant plants exhibited abnormal floral structures, including reduced stamen elongation and delayed anther dehiscence, which led to a failure of pollination and a subsequent reduction of fertility. Our study provides a molecular basis for understanding AP-2–dependent endocytic pathways in plants and their roles in floral organ development and plant reproduction.  相似文献   
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The Titan Acorn barnacle, Megabalanus coccopoma, a native of the tropical eastern Pacific, has become established in the western Atlantic (Brazil and the northern Gulf of Mexico to the Carolinas), northwestern Europe and the western Indian Ocean (Mauritius), and therefore its dispersal capabilities are well known. This study reports its introduction to Japan and confirms its occurrence in Australia. In an attempt to determine the source of this introduction, phylogeographic techniques, involving cytochrome c oxidase I sequences of various widely separate populations of M. rosa and M. volcano, were utilized. No significant genetic differentiation or haplotype patterns between widely separated populations of each of the three species were found. Lack of such differentiation indicates recent geographical isolation and thus negates a null hypothesis predicting that the occurrence of one of more of these species in Australia was natural.  相似文献   
10.
The attractive and characteristically sweet aroma components of baelfruit—a tropical fruit— were investigated. The aroma concentrates possessing the sweet floral and somewhat terpene-like aroma were obtained from both the pulp and peel of fresh baelfruits by means of lyophilization and ether extraction, being analyzed mainly by GC-MS, A total of 39 components were identified. Among these components, terpene alcohols and β-βonone were considered to contribute to the aroma of baelfruit. At optimum ripeness, the fruit with excellent flavor contained a large quantity of an isomeric compound of 3,7-dimethyl-1,5,7-octatrien-3-ol. This compound couldn’t be found in unripe fruit, and seems to be ?mportant in making the baelfruit flavor attractive.  相似文献   
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