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61.
Superior cervical ganglia of rats were centrifuged at 40,000 rpm (160,500 g) for 1 h at 4 degrees C. Most neuronal somata exhibit a minor centripetal domain free of organelles and a major centrifugal domain rich in organelles. The former is occupied by numerous fine granules having low electron density unlike ribosomes in epoxy sections stained with uranium and lead, and is occupied by a meshwork of microtrabecular or filamentous elements similar to that of the centrifugal domain as well as that of the normal cells in PEG (polyethylene glycol)-processed embedment-free sections without staining. The latter centrifugal domain contains regular cell organelles except for neurofilaments without stratification. All the organelles are suspended in the meshwork of microtrabecular or filamentous elements. In immunolight microscopy, NFPs (neurofilament proteins) are confined to the centripetal domain. In immunoelectron microscopy using ultrathin cryosections and the protein A-gold labeling, numerous gold-particles for NFPs were deposited randomly in the centripetal cytoplasmic domain without long linear alignment. In the PEG sections the gold-labelings for NFPs are randomly deposited on portions of the microtrabecular strands in the centripetal domain. After incubation of the centrifuged ganglia in the anterior eye chamber overnight, NFPs-immunoreactivity appears again diffusely throughout the entire cytoplasm of all neuronal somata in immunolight microscopy. The organelle-free domain of the cytoplasm is no longer visible in electron microscopy. The present findings are discussed in relation to the state of the cytoplasmic soluble proteins and the reality of the microtrabecular or filamentous elements in the cytoplasm. 相似文献
62.
A Urisu E Wada Y Kondo F Horiba M Tsuruta T Yasaki K Yamada S Masuda H Komada M Yamada 《Arerugī》1991,40(11):1370-1376
The allergenic activity of Rice protein 16 KD (RP16KD) isolated from water soluble rice proteins was examined by radioallergosorbent test (RAST), RAST inhibition and histamine release assay. All of the 31 sera which showed positive RAST values for rice grain extract were positive for RP16KD RAST. Furthermore, there was a significant correlation (r = 0.56, p less than 0.01) between these RAST values. PR16KD effectively inhibited IgE binding to the rice grain extract disc in RAST inhibition assays using 4 sera with positive RAST values for both antigens. In 17 subjects with positive RAST values for rice grain extract, a significant positive correlation (r = 0.53, p less than 0.05) was found between the maximum percent histamine releases from their leukocytes by rice grain extract and RP16KD. These data strongly suggest that RP16KD is one of the major allergens of rice grain. 相似文献
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Kato T Mizokami M Orito E Ohba K Nakano T Kondo Y Tanaka Y Ueda R Mukaide M Yasuda K Iino S 《Journal of medical virology》1999,57(4):376-382
GB virus C (GBV-C) is related to hepatitis C virus (HCV) and has a similar genomic structure. Some predictors for the efficacy of interferon (IFN) therapy on HCV have been reported: genotype, viral load, IFN dose, and the amino acid substitutions in the NS5A region, designated as the interferon sensitivity determining region (ISDR). To evaluate the correlation between the amino acid substitutions in the GBV-C NS5A region and the response to IFN therapy, single-strand conformation polymorphism (SSCP) analysis was performed in the 12 concomitantly GBV-C-and HCV-infected patients who received IFN therapy at three time points: before, end-point, and after the IFN therapy. The region in the GBV-C NS5A studied includes the amino acids that exhibit some homology to the ISDR and the various substitutions. By SSCP analysis, amplicons were separated into 1-4 bands, which indicated the existence of heterogeneity in each host. However, the deduced amino acid sequences in these bands exhibited no characteristic differences among these strains irrespective of response to IFN therapy. Of the 32 strains separated by SSCP, 7 strains were responders, and 25 were nonresponders. The mean amino acid substitution, compared with the consensus sequence of nonresponders, was 1.00+/-0.93 among responders, and 1.40+/-0.85 among non-responders (P= NS). No correlation between the amino acid sequence in the GBV-C NS5A region and response to IFN therapy was found, indicating that the GBV-C NS5A region dose not act as the ISDR. 相似文献
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Hideo Kunisada Yasuo Yuki Shuji Kondo Ken-ichi Goto 《Macromolecular chemistry and physics.》1993,194(5):1323-1334
Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r1 and r2) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry. 相似文献
68.
We cloned and determined the nucleotide sequences of cDNAs against nucleocapsid protein (NP) mRNA and the genomic RNA of human parainfluenza type 2 virus (PIV-2). The 3' terminal region of genomic RNA was compared among PIV-2, mumps virus (MuV), Newcastle disease virus (NDV), measles virus (MV), PIV-3, bovine parainfluenza type 3 virus (BPIV-3), Sendai virus (SV), and vesicular stomatitis virus (VSV), and an extensive sequence homology was observed between PIV-2 and MuV. Although no significant sequence relatedness was observed between PIV-2 and other viruses, the terminal four nucleotides were identical in the viruses compared, implying a specific role of these nucleotides on the replication of paramyxoviruses. A primer extension analysis elucidated the major NP mRNA initiation site with the sequence UCUAAGCC, which showed a moderate homology with the gene-starting consensus sequences of other paramyxoviruses. On the other hand, the NP mRNA was terminated at the nucleotide stretch AAAUUCUUUUU, and this sequence was conserved in all the PIV-2 genes, indicating that the oligonucleotides will form a part of the gene attenuation signal of PIV-2. Comparisons of NP protein sequence indicated a possible subgrouping of the paramyxoviruses into two groups, one of which is a group including PIV-2, PIV-4, MuV, and NDV, and another is a group including PIV-3, BPIV-3, and SV. This result supports an idea from our previous studies using polyclonal and monoclonal antibodies. Furthermore, our data indicated that the PIV-2 NP protein sequence was more closely related to MV and CDV than to other parainfluenza viruses, PIV-3 and SV. 相似文献
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70.