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51.
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen.  相似文献   
52.
The bimodal molecular weight distribution (MWD) of the polymers and the polymerization rate in the cationic polymerization of styrene by CF3SO3H were studied under a variety of conditions. Both the decrease of the dielectric constant of the reaction mixture and the addition of a common-ion salt (Bu4N+SO3CF) reduced the polymerization rate and the formation of the higher molecular weight portion of the polymers (the high polymer). It appears that of the two propagating species the one which forms the high polymer is more ionically dissociated and more reactive in propagation. Salt effects indicate that in nitrobenzene the propagating species is a solvent-separated ion pair and/or a free ion. The effects of monomer concentration on the bimodal MWD have shown that there are different chain-breaking reactions for the two propagating species. The possibility that the monomer is complexed with one of the growing species is also discussed.  相似文献   
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Despite the huge number of colonized Gram-negative bacteria in the colon, the normal colon maintains its homeostasis without any excessive immune response. To investigate the potential mechanisms involved, human colonic lamina propria mononuclear cells (LPMCs) obtained from uninflamed mucosa were cultured with lipopolysaccharide (LPS) prepared from Bacteroides vulgatus (BV-LPS) or Bacteroides fragilis (BF-LPS), as representatives of indigenous flora, or pathogenic Salmonella minnesota (SM-LPS). Colonic LPMCs failed to produce inflammatory cytokines in response to any type of LPS. Colonic macrophages barely expressed mRNA for MD-2, an essential association molecule for LPS signaling via Toll-like receptor 4. Further, BV-LPS induced CD25 and Foxp3 expression in lymphocytes and CD4(+)CD25(+) cells expressed IL-10 mRNA. Thus, the low expression of functioning LPS receptor molecules and induction of IL-10-producing CD4(+)CD25(+) lymphocytes by indigenous LPS may play a central role in the maintenance of colonic immunological homeostasis.  相似文献   
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Block copolymerizations of 1-chloro-1-octyne (1-ClO) with several substituted acetylenes were examined by means of living polymerization. o-(Trifluoromethyl)phenylacetylene (o-CF3PA), o-(trimethylsilyl)phenylacetylene (o-Me3SiPA), 1-chloro-2-phenylacetylene (1-ClPA), p-butyl-o,o,m,m-tetrafluorophenylacetylene (p-BuF4PA), and tert-butylacetylene (t-BuA) were used as comonomers, and the MoOCl4-n-Bu4Sn-EtOH (mole ratio 1:1:1) catalyst, which is known to effect living polymerization of substituted acetylenes, was employed. When o-CF3PA and 1-CIPA were the comonomers in combination with 1-CIO, block copolymers were exclusively obtained in both orders of monomer addition. In the cases of o-Me3SiPA and p-BuF4PA as comonomers, the copolymerizations initiated from 1-CIO produced block copolymers selectively, whereas the homopolymers of o-Me3SiPA and p-BuF4PA also formed if the order of monomer addition was reversed. The pair of 1-CIO and t-BuA did not selectively yield block copolymers irrespective of the order of monomer addition. Thus, block copolymerization occurred between 1-CIO and monomers that show high “livingness” and close reactivities.  相似文献   
58.
E Wada  A Urisu  Y Kondo  F Horiba  M Tsuruta  T Yasaki  S Masuda  K Yamada  T Kozawa  Y Hida 《Arerugī》1991,40(12):1493-1499
IgE-mediated mechanisms are important in immediate hypersensitive reactions (IHR) to buckwheat. However, a part of subjects with high IgE for buckwheat show no IHR to buckwheat ingestion. Inspite of cross-allergenicity between buckwheat and rice, rice ingestion rarely induces IHR even in subjects with high IgE for rice unlike buckwheat-induced IHR. We speculated that there were some relationships between the presence of IHR to buckwheat and recognition of cross-allergenic determinants on buckwheat components with rice components. We examined IgE-RAST for rice in 58 subjects with positive IgE-RAST for buckwheat. IgE-RAST for Dermatophagoides pteronyssinus (Dp), egg white and cow's milk as unrelated antigens with rice were also assessed for a comparison. Subjects (n = 33) without IHR to buckwheat showed higher IgE-RAST values for rice than those (n = 25) with IHR, whereas there were no differences in IgE-RAST values for Dp, egg white and cow's milk between two groups with and without IHR. IgE-RAST values for buckwheat showed significant close correlations to those for rice in subjects without IHR to buckwheat but not in those with IHR. There were no significant correlations between IgE-RAST values for buckwheat and for Dp, egg white or cow's milk in both groups with and without IHR. These results suggested that the IgE from subjects without IHR to buckwheat recognized cross-allergenic determinants with rice on the buckwheat components.  相似文献   
59.
A new commercial rapid 10-min one-step immunochromatography (IC) test, SAS RSV test, was compared to another IC test, Directigen EZ RSV, employing RT-PCR as the "gold standard" for detecting respiratory syncytial virus. Of 102 clinical samples, 79 were positive by RT-PCR, 66 (82.5%) were positive with the SAS RSV test, and 55 (69.6%) were positive with Directigen EZ RSV. The specificity of the new test was 91.3% (21 of 23), similar to that of Directigen EZ RSV (100% [23 of 23]). This test performs well enough to be used for patient care.  相似文献   
60.
An anticarbamazepine antibody was detected in the serum of a patient with severe carbamazepine-induced serum sickness. We found that the patient's T cells and IgG antibody recognized an epitope which appeared in subjects showing an allergic reaction, as well as that in subjects who showed no allergic reaction, after long-term carbamazepine therapy. These results show that an anti-carbamazepine immune response does not occur in the majority of subjects who undergo long-term carbamazepine therapy without developing allergic symptoms, although the immunodominant haptenic epitope of carbamazepine is present in their sera.  相似文献   
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