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501.
Three dimensional observation of the nerve fibers along the cerebral blood vessels was investigated by scanning electron microscopy. Electron probe X-ray microanalysis was also performed in the cerebral blood vessels treated with peroxidase-antiperoxidase immunohistochemistry intensified by nickel ammonium sulfate. Nerve fibers (2-8 microns in diameter) formed a plexus on the outer surface of the adventitia. After branching, the nerve fibers penetrated the blood vessel adventitia. Substance P-immunoreactive nerve fibers showed a meshwork pattern in the outer layer of the adventitia, and vasoactive intestinal polypeptide (VIP)-immunoreactive nerve fibers revealed a spiral running pattern in the inner layer of the adventitia. Taken together with previous studies, these findings suggest that substance P nerve fibers in the cerebral arteries may not be related to arterial dilatation or constriction, but VIP nerve fibers may be vasodilative.  相似文献   
502.
A new homologue of marinostatin, a peptide proteinase inhibitor, was isolated from marine Alteromonas sp. B-10-31 and designated as marinostatin D. Its amino acid sequence was determined to be Ala-Thr-Met-Arg-Tyr-Pro-Ser-Asp-Asp-Ser-Glu. The reactive site of marinostatin D was determined to be Met(3)-Arg(4) on the basis of the reversible cleavage and regeneration of the scissile bond catalyzed by TLCK-chymotrypsin.  相似文献   
503.
Bacteria isolated from two salmonid hatcheries were screened for antiviral activity against infectious hematopoietic necrosis virus (IHNV) to ascertain the presence of bacteria with anti-IHNV activity in the aquatic environment. Out of 710 bacterial isolates from the water and sediment samples, 190 strains showed anti-IHNV activities of more than 50% plaque reduction. These antiviral activities were detected predominantly in Pseudomonas, Aeromonas/Vibrio, and coryneforms. In one hatchery, the bacteria with antiviral activities were more prevalent in sediment samples than in water samples. Seventy-seven percent of the isolates with higher antiviral activities (greater than 90% plaque reduction) belonged to Pseudomonas.  相似文献   
504.
Serum constituents and liver of the wild male suncus as well as of those bred and fed in our laboratory were examined serologically and histologically. The following results were obtained: The serum glutamic-oxaloacetic transaminase, gamma-glutamyl transaminase, inorganic phosphate, blood urea nitrogen, creatinine, uric acid, and zinc turbidity test levels of wild suncus were higher than those of 4 and 8 week old fed suncus. The total cholesterol level of wild suncus was lower than those of 4 and 8 week old fed suncus. In wild suncus, the total bilirubin and direct bilirubin levels were higher, and the Ca and albumin levels were lower than those of 4 week old fed suncus. However, no significant differences were observed between the wild and the 8 week old fed suncus. Although the alkaline phosphatese and thymol turbidity test levels of wild suncus were larger than those of 8 week old fed suncus, no significant differences were observed between the wild and the 4 week old fed suncus. The histological study revealed the presence of fatty droplets in only 2 of the 67 wild suncus examined while fatty droplets (grade +) were observed in almost all the fed suncus. In one case of the wild suncus, moderate round cell infiltration in interlobular connective tissue was found.  相似文献   
505.
506.
The inheritance of a new lethal mutant rate showing congenital osteochondrodysplasia with systemic subcutaneous edema (ocd for the gene symbol) was examined by crossings between the carriers and between F1s derived from the carrier x Long-Evans crossing. The ratio of the affected to phenotypically normal was 276:89 in pups derived from the crossings between the carriers and 83:17 in those at the LE-F2 generation derived from the proven carriers of the LE-F1 animals, thus showing that the ratio is 3:1. The female:male ratio was 47:42 in the affected and 133:143 in the phenotypically normal pups, showing the sex ratio is 1:1, irrespective of the affected or phenotypically normal. The ratio of affected:carrier:noncarrier was 26:58:27 in littermates derived from the crossings between the carriers, showing the ratio is 1:2:1. The results fitted well to the hypothesis that the inheritance is a single autosomal recessive trait. Independence of the gene from linkage group I was also revealed, because the ratio of colored to albino was 14:3 and 65:18 in affected and phenotypically normal pups at the LE-F2 generation, respectively, which fitted to the ratio of 3:1.  相似文献   
507.
Monoclonal antibodies specific for queuine have been prepared. Synthetic 9-(5-carboxypentyl)queuine (cp9Q) was conjugated with bovine serum albumin (BSA) or keyhole limpet hemocyanin (KLH), and the conjugate was used to immunize BALB/c mice by intraperitoneal and subcutaneous injection. Monoclonal antibodies were subsequently obtained by fusion of spleen cells and the mouse myeloma cell line X63Ag8U1. An enzyme-linked immunoabsorbent assay (ELISA) using o-phenylenediamine as peroxidase substrate was used for screening of clones and characterization of antibodies. Inhibition experiments with various homologous nucleosides revealed that the monoclonal antibody designated as 2D8E6 has no cross-reactivity with guanosine, adenosine or 7-methylguanosine.  相似文献   
508.
The cytochrome P450 CYP78A5/KLUH in Arabidopsis thaliana is predicted to be involved in the synthesis of a mobile signal molecule that has a pleiotropic function that is distinct from classical phytohormones. CYP78A5 has five close relatives in Arabidopsis. We first investigated their functions, focusing on the plastochron, leaf size, and leaf senescence. Our analyses revealed that CYP78A5 and CYP78A7 are involved in the plastochron and leaf size, and CYP78A6 and CYP78A9 are involved in leaf senescence. Complementation analyses using heterologous promoters and expression analyses suggested that CYP78A isoforms have a common biochemical function and are functionally differentiated via organ-specific expression. The altered meristem program1 (amp1) carboxypeptidase mutant shows a phenotype very similar to that of the cyp78a5 mutant. Complementation analyses using boundary and organizing center-specific promoters suggested that both CYP78A5 and AMP1 act in a non-cell-autonomous manner. Analyses of multiple cyp78a mutants and crosses between cyp78a and amp1 mutants revealed that AMP1/LIKE AMP1 (LAMP1) and CYP78A isoforms regulate plastochron length and leaf senescence in the same genetic pathway, whereas leaf size is independently regulated. Furthermore, we detected feedback regulation between CYP78A6/CYP78A9 and AMP1 at the gene expression level. These observations raise the possibility that AMP1 and CYP78A isoforms are involved in the synthesis of the same mobile signal molecule, and suggest that AMP1 and CYP78A signaling pathways have a very close, albeit complex, functional relationship.

ALTERED MERISTEM PROGRAM1 and isoforms of the cytochrome P450 CYP78A regulate plastochron and leaf senescence in non-cell-autonomous/organ-specific manners, and have a close, albeit complex, and functional relationship.  相似文献   
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