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81.
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To evaluate the potential role of NK1.1 (CD161c) cells in autoimmune uveoretinitis, we treated experimental autoimmune uveoretinitis (EAU)-susceptible mice with anti-CD161c antibodies (PK136) to deplete natural killer (NK) cells. Injection of anti-CD161c antibodies deleted NK cells from the peripheral blood of EAU-susceptible mice. The T cell proliferative response against the ocular autoantigen K2 was not suppressed in mice treated with anti-CD161c antibody when compared with T cells from control mice. Although mice treated with anti-CD161c developed EAU, the clinical severity on days 17 and 19 after induction of EAU was significantly mild in anti-CD161c-treated mice compared with control mice. In addition, the histopathological severity of EAU was significantly milder in mice treated with anti-CD161c antibodies than controls 21 days after induction of EAU. Our results indicate that the severity of EAU is augmented by NK1.1(+) NK cells.  相似文献   
83.
A simple membrane immunoassay assay system, Quik Pack, for the detection of hepatitis C virus antibody was compared with two enzyme-linked immunosorbent assays (ELISAs) in a study of 600 serum samples. Quik Pack exhibited excellent sensitivity and specificity: 96.0 and 99.7%, respectively, versus the ELISA-2 and 99.7 and 99.4%, respectively, versus the ELISA-3.  相似文献   
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BACKGROUND: Chlamydia pneumoniae is a frequent causative agent of acute respiratory disease and has been recently reported as a possible cause of asthma. We investigated the prevalence of C. pneumoniae infections in childhood patients with acute exacerbations of asthma. METHOD: One hundred twenty-six childhood patients with acute exacerbations of asthma, 77 with acute bronchitis and 22 Respiratory syncytial virus infections were studied. Serum samples were obtained and tested for C. pneumoniae-specific IgM antibody by Enzyme-Linked ImmunoSorbent Assay (ELISA). RESULTS: C. pneumoniae IgM-positive results were observed in 48.4% (Index value>or=1.60) and 23% (Index value>or=1.10) of patients with acute exacerbations of asthma. The prevalence of C. pneumoniae-specific IgM was significantly higher in asthma cases than in other subjects (p<0.05). CONCLUSION: Our data suggest that C. pneumoniae infection may trigger acute exacerbations of childhood asthma.  相似文献   
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We have established the electrical polarization method of hydroxyapatite (HA) coatings (HAC) for clinical use, such as dental and orthopedic implants. The HAC examined in the current study was prepared in titanium substrates by plasma spraying of beta-tricalcium phosphate (TCP) powders followed by hydrothermal treatment. The prepared HAC consisted of a single phase of HA, because the starting TCP phase was completely transformed to the HA phase during the posthydrothermal treatment. Polarization was carried out at the elevated temperature of 400 degrees C under a d.c. field of 1 kV . cm(-1). The electrical measurements showed that the stored charges of the polarized HAC were greater than the reported value of the sintered ceramic HA. The enhanced bioactivity of the polarized HAC was demonstrated using 1.5 simulated body fluid (SBF). The crystal growth from the SBF solution was accelerated on the negatively charged surface in comparison with the untreated HAC. Similar to the polarized ceramic HA, the current results confirmed that the bioactivity of HAC would be effective for improving the initial fixation by polarization.  相似文献   
89.
Expression of the Arabidopsis CGS1 gene that codes for cystathionine gamma-synthase is feedback regulated at the step of mRNA stability in response to S-adenosyl-L-methionine (AdoMet). A short stretch of amino acid sequence, called the MTO1 region, encoded by the first exon of CGS1 itself is involved in this regulation. Here, we demonstrate, using a cell-free system, that AdoMet induces temporal translation elongation arrest at the Ser-94 codon located immediately downstream of the MTO1 region, by analyzing a translation intermediate and performing primer extension inhibition (toeprint) analysis. This translation arrest precedes the formation of a degradation intermediate of CGS1 mRNA, which has its 5' end points near the 5' edge of the stalled ribosome. The position of ribosome stalling also suggests that the MTO1 region in nascent peptide resides in the ribosomal exit tunnel when translation elongation is temporarily arrested. In addition to the MTO1 region amino acid sequence, downstream Trp-93 is also important for the AdoMet-induced translation arrest. This is the first example of nascent peptide-mediated translation elongation arrest coupled with mRNA degradation in eukaryotes. Furthermore, our data suggest that the ribosome stalls at the step of translocation rather than at the step of peptidyl transfer.  相似文献   
90.
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.  相似文献   
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