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1.
We clarified the roles of IL-1 beta in peripheral neural regeneration after axotomy in a three-dimensional collagen gel culture system ranging from a single neurone to a dorsal root ganglion (DRG) explant with its associated nerve bundles. Application of 30 U/ml IL-1 beta to the culture systems clearly enhanced neural regeneration. This regeneration was evident in transected nerve terminals of DRG explants with or without associated nerve bundles, but not in dissociated single neurones. Neural survival was not affected by IL-1 beta in any of these culture systems. These results suggest that IL-1 beta stimulates surrounding non-neuronal cells to secrete neurotrophic factors, thus enhancing neurite regeneration from transected nerve terminals in cultured adult DRG explants. 相似文献
2.
Chinese schoolchildren and adults with strenuous visual tasks routinely perform massage-and-pressure exercises on selected acupressure points around the eyes. This practice, taught by the Jing-Luo school of acupuncture for more than 4000 years, is claimed to prevent and cure myopia and other afflictions thought to result from visual close work. A four-week pilot experiment was carried out with the aim of designing a proper study on the possible short-term benefits of eye acupressure programmes. Questionnaire data revealed that the subjects did experience various eye/vision symptoms as a result of the 90 min experimental task. This could not be verified by the measurements of accommodation precision and critical flicker fusion, nor could any beneficial effects of acupressure be seen over the four experimental weeks. 相似文献
3.
Kojiro Nakai Yasunori Oumi Haruyuki Horie Tsuneji Sano Hideaki Yoshitake 《Microporous and mesoporous materials》2007,100(1-3):328-339
Bromination and subsequent ethylenediamine substitution of the CC double bond in mesoporous ethylenesilica were carried out to explore the characteristics of this periodic mesoporous organosilica. The structures of the products (BrPMO and EDA–BrPMO, respectively) were analysed by IR, Br K-edge EXAFS and NMR spectroscopies, as well as X-ray diffraction and nitrogen adsorption. We showed (1) that the formulae of the two products that formed were [CHBrSiO1.5]0.45[CHSiO1.5]0.55 and [NH2CH2CH2NHCHSiO1.5]0.05 [CHBrSiO1.5]0.40[CHSiO1.5]0.55, respectively, (2) that the addition of Br2 at room temperature occurred on the CC double bonds with disturbing the framework structure, (3) that IR absorption band of CC bonds that reacted with Br2 is significantly different from that of inactive CC bond, (4) that the length of the C–Br bond was considerably longer than in conventional alkyl bromides, and (5) that a large proportion of the ν(C–Br) band remained at the same position in the IR absorption spectrum after the ethylenediamine (EDA) substitution, while a new ν(C–Br) absorption also appeared. The mechanisms of these reactions are discussed at both the micro and mesoscopic levels.
Arsenate adsorption on EDA–BrPMO, in which the EDA is directly bound to the “surface” of the mesopores, was compared with adsorption on EDA–Pr–PMO, which was prepared by the direct synthesis of 3-chloropropyl-functionalized mesoporous ethanesilica followed by the substitution of Cl with EDA. The strength of the adsorption, as measured with the distribution coefficient, was greater for the former adsorbent than the latter. The origin of this difference was attributed to the distance between amino group and the surface. 相似文献
4.
Okamura T Takeno T Dohi M Yasumasa I Hayashi T Toyoda M Noda H Fukuda S Horie N Ohsugi M 《Journal of Bioscience and Bioengineering》2000,89(5):474-478
With thrombosis a major cause of death in Japan and the Western world, thrombin-inhibitory agents that constrain the formation of fibrin are sought. We screened for basidiomycetes showing anti-thrombin activity and isolated Laetiporus sulphureus. However, it was difficult to cultivate and its form was not satisfactory. We therefore used protoplast fusion between L. sulphureus and the commonly cultivated basidiomycete Hypsizygus marmoreaus to obtain cultivable basidiomycetes that produced an anti-thrombin substance. For the protoplast fusion of L. sulphureus and H. marmoreaus, the protoplast concentration, alternating electric field intensity, dielectrophoresis duration, and field pulse intensity used were of 1 x 10(7) protoplasts/ml, 100 V/cm.1 MHz, 60 s, and 8 kV/cm, respectively. The number of regenerated colonies obtained was 4961, from which 43 strains were selected for electrophoretic analysis. Four of the fusants were found to have a band from each parent in isozyme patterns obtained using their crude extract. The fruiting bodies of the fusants were very similar to those of H. marmoreaus. Crude extract from each of the fusants and from L. sulphureus showed anti-coagulative activity in terms of the thrombin clotting time. We thus obtained improved basidiomycetes that produce an anti-thrombin substance, are easily cultivated, and whose form resembles H. marmoreaus, a commonly used culinary mushroom. 相似文献
5.
Quantitative and qualitative microbiological examination was carried out on cloacal and oviductal contents pre- and postinfection with Salmonella enteritidis (SE) intracloacally or intravaginally. Before inoculation with SE, the means +/- standard deviation (SD) of total bacterial counts, anaerobic bacterial counts, and aerobic bacterial counts in the cloaca were log10 7.7 +/- 0.7, 7.4 +/- 0.2, and 6.9 +/- 0.8 colony-forming units (CFU)/g, respectively. The predominant bacteria were Bacteroidaceae, Lactobacillus, and Escherichia coli. Before inoculation with SE, the means +/- SD of total bacterial counts, anaerobic bacterial counts, and aerobic bacterial counts in the vagina were log10 5.7 +/- 1.4, 5.5 +/- 1.3, and 3.6 +/- 2.7 CFU/g, respectively. Bacteroidaceae and Lactobacillus were predominant. Following inoculation with SE, only the cloacal population of Lactobacillus in hens inoculated intracloacally was significantly increased compared to that before the inoculation. Other indigenous microflora were stable even after the inoculation. In the uterus, very few bacteria, Lactobacillus and Staphylococcus, were isolated. Five of 20 eggs (25%) from hens inoculated with SE intravaginally were positive for SE, whereas no SE was recovered from 22 eggs in hens inoculated with SE intracloacally. SE was recovered from the uterus after intravaginal inoculation with SE and from the vagina after intracloacal inoculation with SE. Contamination may ascend from the cloaca into the lower parts of the oviduct and subsequently contaminated eggs may occur. 相似文献
6.
J Suzuki M Isobe S Yamazaki S Horie Y Okubo M Sekiguchi 《Canadian Metallurgical Quarterly》1998,40(2):307-313
BACKGROUND & AIMS: Interleukin 12 (IL-12) is a heterodimeric, macrophage-derived cytokine that is elevated in Crohn's disease (CD). Epstein-Barr virus-induced gene 3 (EBI3) is a recently characterized human glycoprotein that is homologous to the 40-kilodalton chain of IL-12 and forms a heterodimer with the 35-kilodalton chain of IL-12. We investigated the expression of EBI3 in colonic mucosa of normal control subjects, patients with ulcerative colitis (UC), and patients with CD. METHODS: Colonic tissue was analyzed for messenger RNA (mRNA) expression by quantitative polymerase chain reaction and for protein expression by immunohistology and Western blotting. RESULTS: EBI3 mRNA was present in intestinal biopsy specimens from healthy subjects and patients with CD but was elevated only in active UC. EBI3 levels in UC specimens correlated with histological scores of activity and T-cell infiltration. EBI3-positive cells that had a shape consistent with that of macrophages were identified in the lamina propria, and protein was detected by Western blotting. CONCLUSIONS: EBI3 is a novel IL-12-related cytokine that is expressed by macrophage-like cells in normal intestine and CD and has enhanced expression in active UC but not in active CD. 相似文献
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8.
Copolymerization of unsaturated polyester with styrene in water-in-oil (W/O) type emulsion was carried out with the use of various basic compounds as emulsifiers. It was found that a stable, gellike W/O type emulsion of unsaturated polyester resin is formed only when pKa's of the bases are above 6 and their concentrations are higher than some critical value. In these conditions, water can be dispersed in emulsion up to 900% to the resin. By polymerization, the stable W/O type emulsion is transformed to a white solid copolymer which is dry to the touch and which contains 90–95% of initially added water. It was confirmed that the basic compounds react with the carboxylic group of the polyester to form at the water-resin interface polyester salts, which act as true emulsifying agents. The stabilization mechanism of the emulsion at various concentrations of the polyester salt was investigated, mainly by microscopic observations, and an interpretation of the critical value of emulsifier concentration is proposed. 相似文献
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