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Whole-genome sequencing was used to compare longitudinal isolates of Staphylococcus aureus that developed resistance to oxacillin (MIC up to 16 μg/ml). The mecA gene was absent. A novel 5-bp TATCC frameshift insertion in a gene encoding an ABC transporter similar to that of the teichoic acid translocation ATP-binding protein TagH and a 3-bp GCT nonframeshift insertion in the pdhA pyruvate dehydrogenase gene were detected in the oxacillin-resistant isolates.  相似文献   
75.
Mycobacterium paraffinicum has been newly recognized as a species. A case of symptomatic pulmonary infection caused by M. paraffinicum is described, and as far as we know, this is the first case of the organism as a human pathogen.  相似文献   
76.
A 15-year-old boy with caecal haematoma required a right hemicolectomy due to development of small bowel obstruction and near caecal perforation having presented several days after an episode of minor trauma. The position of the caecum between intraperitoneal and extraperitoneal bowel requires special treatment considerations. This is a unique case in an adolescent because caecal haematoma usually presents acutely with abdominal pain.  相似文献   
77.
The present study examined whether growth characteristics of diffusely growing non-Hodgkin's lymphomas (NHL) may differ as a function of stage. Among 105 NHL of various types and sub-types (REAL [Revised European-American Lymphoma] classification), localized (Ann Arbor pathologic stages I + II) lymphomas exhibited clearly higher indices for mitotic activity, apoptosis and cell turnover, as well as a significantly lower percentage of cells containing immunohistochemically detectable bcl-2 protein, than disseminated (stages III + IV) NHL. A similar pattern emerged when high-grade (Kiel classification) lymphomas only were evaluated. Low-grade NHL showed analogous, but less marked, stage-dependent characteristics, with the exception of median percentages of bcl-2+ cells, which remained comparable in all stages. Our findings are consistent with the notion that dissemination of diffusely growing NHL is usually associated with reduced cell turnover and, in high-grade lymphomas, with the generation of longer-lived cells. © 1996 Wiley-Liss, Inc.  相似文献   
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Human alveolar macrophages (AM phi) from thirteen patients, who were suffering from various lung diseases were harvested by bronchoalveolar lavage. Peripheral blood monocytes from eight healthy donors were isolated by Ficoll-Hypaque gradient centrifugation and adherence to plastic surface. To detect the VEP13 antigen (CD16) on these cells, a rosette assay employing ox erythrocytes coated by the CrCl3 method with purified VEP13 monoclonal antibody (Eo-VEP13) was used. A mean of 31.3% of freshly isolated AM phi and 3.9% of blood monocytes formed Eo-VEP13 rosettes. Monocytes cultured for 3 or 6 days in the presence of a supernatant from mouse L929 cells, which had been shown previously to improve long-term viability of human monocytes in culture, showed 12.5% and 25.3% Eo-VEP13 rosettes, respectively. No significant increase in VEP13 antigen expression was noted by culturing monocytes without L929 cell supernatant. The factor in L929 supernatant that induces VEP13 antigen expression has not been identified. Tunicamycin at 10 micrograms/ml inhibited significantly VEP13 antigen expression on monocytes. In contrast, IgG rosette formation was not reduced by tunicamycin. Our data show that subpopulations of native human AM phi and peripheral blood monocytes cultured in presence of a supernatant of L929 fibroblasts containing mainly murine CSF may express the CD16 antigen, which is normally found on large granular lymphocytes (LGL). Suppression by tunicamycin indicates that Fc receptor glycosylation takes place during a later differentiation step of mononuclear phagocytes.  相似文献   
80.

Objectives

Hybrid composite restorations in posterior teeth were evaluated over 15 years using the semiquantitative Clinical, Photographic and Micromorphologic (CPM) index. It was a further aim to quantitate the surface morphology by three-dimensional scanning electron microscopy (3D-SEM).

Methods

Thirty seven hybrid composite restorations (Ketac-Bond/Visio-Molar X, ESPE, Seefeld/Germany) were longitudinally followed up.Parallel to clinical assessment replicas were taken at baseline, after 1, 5, 10 and 15 years and evaluated by SEM, and profilometrical analyses of 3D-SEM data were computed. The profilometrical results were statistically analysed by ANOVA. The level of significance was set to p < 0.05.

Results

The semiquantitative micromorphological evaluation exhibited the most considerable deterioration within the first year and up to 5 years of function. Less change was detected during the next 10 years. The profilometrical quantification showed raising depth of the negative marginal ledges with a mean of 27.2 μm (range 0.6–94.5 μm) after 10 years, with no statistically significant changes from 5 to 10 and 10 to 15 years. The 3D-SEM revealed marginal grooves beneath the level of the ledges (mean 34.5 μm after 5 years) within the bonding zone, exposing enamel margins. Leakages, marginal fractures and surface roughness did not seriously deteriorate the quality of restorations.

Conclusions

Hybrid composite restorations of Class I and II cavities surviving the first five years performed well over 15 years of function. Quantitative 3D-SEM profilometrical measurements revealed the dynamics of marginal behaviour over time.

Clinical significance

Long-term parallel clinical and micromorphological evaluation of posterior composite restorations of Class I and Class II cavities documented the clinical safety and acceptable longevity. The longitudinal 3D micromorphologic assessment of the surface changes and of the marginal behaviour revealed deteriorating as well as improving factors hidden in clinical performance.  相似文献   
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