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71.
We report the case of a 70 years old patient hospitalized for renal insufficiency and deterioration of the general state. The electrophoresis of serum proteins on freezing of agarose reveals the presence of a discrete peak of monoclonal pace on the level of the gammaglobulines identified by serum immunofixation like IgM of the kappa type. The research of the cryoglobulinemia carried out in a laboratory of city was made positive and typified like a monoclonal cryoglobulinemia IgM kappa, thus directing the diagnosis towards a disease of Waldenstr?m. However, the result of the biopsy medullary made exclude any lymphoprolifératif syndrome. The positivity of the serology of hepatitis B justified a second request for study of the cryoglobulinemia, carried out within our laboratory. The cryoglobuline was typified like mixed (IgM kappa monoclonal and IgG polyclonales). This result associated with the immunological assessment and the renal biopsy made retain for our patient the diagnosis of a kidney vasculitis connected to an infection chronicle by the virus of hepatitis B. This observation points out the interest of the preanalytic, analytic and post analytic phases in the study of the cryoglobulinemias. A good technical control is today the only guarantee of the quality of the result of this examination which has large importance in internal medicine in the etiologic assistance with the diagnosis of certain clinical demonstrations.  相似文献   
72.
Tuberculosis/HIV-1 co-infection is responsible for thousands of deaths each year, and previous studies have reported that co-infected individuals display major morphological alterations in tissue granulomas. The purpose of this study was to evaluate immunohistopathological characteristics in lung tissues from pulmonary TB/HIV-1-co-infected individuals. Following autopsy, tuberculosis-positive HIV-1-negative cases displayed granulomas with normal architecture, mainly composed of a mononuclear infiltrate with typical epithelioid, as well as giant cells, and exhibiting caseous necrosis. In contrast, lesions from the TB/HIV-1-co-infected group showed extensive necrosis, poorly formed granulomas, and a marked presence of polymorphonuclear cells. More importantly, TNF staining was greatly reduced in the TB/HIV-1-co-infected individuals. Our data suggest that HIV-1 infection alters the organization of pulmonary granulomas by modulating TNF and, possibly, cell trafficking, leading to an impaired anti-tuberculosis response.  相似文献   
73.
Cutaneous mucormycosis in a young, immunocompetent girl.   总被引:2,自引:0,他引:2  
We report a case of cutaneous mucormycosis in a healthy, immunocompetent young girl (age 14 years). The patient had a 5-year history of a slowly enlarging, erythematous plaque with slight elevated, scaling, circinate borders on the right thigh. Histopathology showed a granulomatous infiltrate with broad, pale, non-septate hyphae. Mycological study identified Mucor hiemalis (Wehmer).  相似文献   
74.
75.
The use of an adequate method for evaluation of the adhesion of root canal filling materials provides more reliable results to allow comparison of the materials and substantiate their clinical choice. The aims of this study were to compare the shear bond strength (SBS) test and push-out test for evaluation of the adhesion of an epoxy-based endodontic sealer (AH Plus) to dentin and guttapercha, and to assess the failure modes on the debonded surfaces by means of scanning electron microscopy (SEM). Three groups were established (n=7): in group 1, root cylinders obtained from human canines were embedded in acrylic resin and had their canals prepared and filled with sealer; in group 2, longitudinal sections of dentin cylinders were embedded in resin with the canal surface smoothed and turned upwards; in group 3, gutta-percha cylinders were embedded in resin. Polyethylene tubes filled with sealer were positioned on the polished surface of the specimens (groups 2 and 3). The push-out test (group 1) and the SBS test (groups 2 and 3) were performed in an Instron universal testing machine running at crosshead speed of 1 mm/min. Means (±SD) in MPa were: G1 (8.8±1.13), G2 (5.9±1.05) and G3 (3.8±0.55). Statistical analysis by ANOVA and Student''s t-test (α=0.05) revealed statistically significant differences (p<0.01) among the groups. SEM analysis showed a predominance of adhesive and mixed failures of AH Plus sealer. The tested surface affected significantly the results with the sealer reaching higher bond strength to dentin than to guttapercha with the SBS test. The comparison of the employed methodologies showed that the SBS test produced significantly lower bond strength values than the push-out test, was skilful in determining the adhesion of AH Plus sealer to dentin and gutta-percha, and required specimens that could be easily prepared for SEM, presenting as a viable alternative for further experiments.  相似文献   
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77.
The authors characterized the genera of mycelial fungi found in samples of expressed human milk received through home collection by the Human Milk Bank of the Instituto Fernandes Figueira in Rio de Janeiro. A total of 821 samples of expressed human milk were taken randomly from bottles collected at home by the milk donors themselves and were investigated for molds, yeasts, and mesophilic microorganisms. The analyses showed the occurrence of molds and yeasts in 43 (5.2%) of the samples, with counts reaching 103CFU/ml. Some 48 strains of mycelial fungi were identified by standard laboratory techniques, including: Aspergillus Niger group (6.3%), Aspergillus sp. (4.2%), Paecilomyces sp. (12.6%), Penicillium sp. (60.4%), Rhizopus sp. (2.0%), and Syncephalastrum sp. (14.5%). The authors discuss the importance of donor hands' asepsis prior to collecting human milk.  相似文献   
78.
This study examines the patient in group psychotherapy, describing factors that provide changes during the process and the particularities of this therapeutic mode. Based on the available literature and the authors' systematic experience throughout thirty years of group therapeutic work, the variables that determine the commitment of the group members in a productive and well-succeeded therapeutic relation are discussed. It is emphasized how the patients assimilate the psychotherapeutic process and the way in which they participate in achieving their own improvement.  相似文献   
79.
Water samples (n = 183) from Portuguese rivers were tested for the presence of endocrine disruptors using the recombinant yeast assay (RYA) combined with chemical identification of compounds having endocrine-disruption properties by liquid chromatography coupled to mass spectrometry. Ten selected locations were sampled monthly for a period of 20 months, from April 2001 to December 2002. More than 90% of samples showed either no detectable or low levels of estrogenicity (<0.1 ng/L of estradiol equivalents). The remaining samples (17 in total, 9.3%) showed estrogenicity values ranging from 0.1 to 1.7 ng/L of estradiol equivalents; only two samples showed values greater than 1 ng/L of estradiol equivalents. Most highly estrogenic samples (13 of 17 samples) originated in five sampling sites clustered in two zones near Porto and Lisbon. Chemical analysis detected alkylphenolic compounds (octyl- and nonylphenol plus nonylphenol ethoxylates) in all samples, albeit at concentrations less than 1 microg/L for each compound in 80% of samples. Total analyte concentration exceeded 10 microg/L in only 10 samples, with all but one of those originating from only two sampling sites. In these two locations, a good correlation was observed between the concentrations of octylphenol, nonylphenol, and to a lesser extent, bisphenol A in the samples and their estrogenicity values as calculated by RYA. We conclude that estrogenic activity can be explained by alkylphenol contamination in only these sites; for the remainder, we propose that pesticides and urban waste may be the main factors responsible for estrogenic contamination.  相似文献   
80.
Gene gun mucosal DNA immunization of sheep with a plasmid expressing the env gene of Maedi-Visna virus (MVV) was used to examine the protection against MVV infection in sheep from a naturally infected flock. For immunization, sheep were primed with a pcDNA plasmid (pcDNA-env) encoding the Env glycoproteins of MVV and boosted with combined pcDNA-env and pCR3.1-IFN-gamma plasmid inoculations. The pcDNA plasmid used in the control group contained the lacZ coding sequences instead of the env gene. Within a month post-challenge, the viral load in the vaccinated group was lower (p < or = 0.05) and virus was only detected transiently compared with the control group. Furthermore, 2 months later, neutralizing antibodies (NtAb) were detected in all the control animals and none of the vaccinated animals (p < or = 0.01). These results demonstrated a significant early protective effect of this immunization strategy against MVV infection that restricts the virus replication following challenge in the absence of NtAb production. This vaccine protective effect against MVV infection disappeared after two years post-challenge, when active replication of MVV challenge strain was observed. Protection conferred by the vaccine could not be explained by OLA DRB1 allele or genotype differences. Most of the individuals were DRB1 heterozygous and none was totally resistant to infection.  相似文献   
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