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461.
An outbreak of pertussis was recognized in a highly immunized sixth-grade class of schoolchildren. Among 43 children aged 11–12 years in the class, 38 had been immunized with three doses or more of DTP containing whole-cell pertussis vaccine, two with two doses of DTP and three children were unimmunized. The last DTP vaccines had been given 6–10 years before the outbreak. A total of eight children with pertussis suffering paroxysmal coughing attacks for 3 weeks or more were identified, seven being fully immunized and one unimmunized. Among the eight cases, two were confirmed by both culture and serology and one by serology alone. The attack rate in fully immunized children was 18.4% (7/38). Secondary spread of pertussis was identified in five of the households from which the eight patients originated. A total of six cases of pertussis from these five households were identified, and two of these were culture-confirmed. These observations suggest that vaccine-induced immunity weakens considerably 6–10 years after vaccination, and that booster immunization with DTP instead of DT is therefore recommended for the control of pertussis.  相似文献   
462.
ABSTRACT Azosemide produced bent long bones such as wavy ribs in rat fetuses, but these abnormalities could not be found in the adult offspring. In the present study, the morphological sequence from appearance to disappearance of wavy ribs was examined in cartilage-bone double stained specimens of fetuses and pups from mothers treated with azosemide on day 16 of gestation. The first detected change of the skeletal abnormalities was inhibition of bone deposition in the ossification centers of fetuses on day 17 of gestation. A bend first appeared on day 18 of gestation, and consisted of cartilage and portion stained neither alcian blue nor alizarin red S. Ossification began at this stage. From day 19 of gestation onward, ossification progressed toward the ends of the cartilage model including the bent region. The bend disappeared in most pups as bone in the bent region grew on days 10–14 postpartum. The present findings imply that the bend may be caused by difference in growth between cartilaginous and unstained portions, and a surface remodeling of bones may straighten the bend in the subsequent bone growth.  相似文献   
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465.

Objective:

To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM.

Material and Methods:

Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey''s test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level.

Results:

Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s).

Conclusions:

All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinker.  相似文献   
466.
Tetra-spans transmembrane family (TSTF) members (CD9, CD37, CD53, CD63, CD81 and CD82) have potent effects on cell growth, motility and adhesion in various cells. However, little is known about their expression in human skin. Using immunohistological techniques, we have studied the localization of all six members of TSTF in normal and carcinomatous human keratinocytes. CD9, CD81 and CD82 were expressed in the entire living layers of the epidermis. Their staining pattern was quite similar, and was mainly intercellular with occasional intracellular immunoreactivity. CD53 expression was confined to the intercellular spaces of the upper spinous or granular layer in the normal epidermis. No clear-cut expression of CD63 could be detected in the epidermis. CD37 was not detected at all. Cultured human keratinocytes also expressed CD9, CD81 and CD82 at the surface membrane of cell-cell boundaries. Expression of CD37 and CD53 was negative in cultured keratinocyte, while CD63 was clearly localized in the cytoplasmic lysosomes. An immunoprecipitation assay revealed that α3β1 integrin is molecularly associated with CD9. The expression of CD9, CD81 and CD82 was markedly down-regulated in basal cell carcinoma but not in Bowen's disease. The abundant and differential expression of TSTF molecules and the selective association of CD9 with α3β1 integrin suggest that the TSTF molecules may be involved in the regulation of epidermal differentiation and integrity in vivo.  相似文献   
467.
The autologous mixed lymphocyte reaction (auto-MLR) was studied to test the interactions between immunocompetent cells in patients with psoriasis. The auto-MLR in 20 patients with psoriasis was significantly lower than in 16 normal controls. Lower values were found in untreated psoriatic patients than in those in remission following treatment. The values in the latter group were significantly lower than in controls and in six patients with atopic dermatitis in remission. The tendency for an increase in the auto-MLR with a decrease in disease activity was further confirmed in five patients studied before and after treatment. In contrast, the allogeneic lymphocyte reaction (allo-MLR) in psoriatics was similar to that in normal controls.  相似文献   
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