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排序方式: 共有810条查询结果,搜索用时 15 毫秒
71.
Amaral R Giraldo PC Gonçalves AK Junior JE Santos-Pereira S Linhares I Passos MR 《International journal of STD & AIDS》2007,18(11):770-773
To determine the frequency of abnormal vaginal flora and bacterial vaginosis (BV) in female sex workers (FSW) and the association between douching and vaginal microflora imbalance, a cross-sectional study enrolled 94 users and 61 non-users of vaginal douching. The social-demographic and sexual profile of these women was obtained and their abnormal vaginal flora, BV, vaginal candidiasis, trichomoniasis and cytolitic vaginosis on blinded samples were identified by Gram stain. A stepwise multivariate regression determined the risk of development of vaginal microflora imbalance. Prevalence of abnormal flora, BV, candidiasis, trichomoniasis and cytolytic vaginosis in the entire FSW was 75.5%, 51.0%, 5.1%, 0.64% and 1.9%, respectively. There were no significant differences in these findings between users and non-users of vaginal douching. Regression analysis did not identify any increased risk for altered vaginal flora or BV in vaginal douche users. In conclusion, vaginal douching did not increase the rate of these alterations in FSW. 相似文献
72.
Carvalho LP Passos S Bacellar O Lessa M Almeida RP Magalhães A Dutra WO Gollob KJ Machado P de Jesus AR 《Parasite immunology》2007,29(5):251-258
Cutaneous (CL) and mucosal leishmaniasis (ML) are characterized by a predominant type 1 immune response (IFN-gamma and TNF-alpha production) and strong inflammatory response in the lesions with few parasites. This exacerbated type 1 response is more evident in ML as compared to CL. Our main hypothesis is that a differential immune regulation of T cell activation leads to over reactive T cells in ML. In the present study, we investigated immunological factors that could explain the mechanisms behind it by comparing some immune regulatory mechanisms between ML and CL patients: frequency of cells expressing co-stimulatory molecules, apoptotic markers, T cell activation markers; and ability of neutralizing antibodies to IL-2, IL-12 and IL-15 do down-regulate IFN-gamma production in leishmania antigen-stimulated peripheral blood mononuclear cells (PBMC). Interestingly, in CL anti-IL-2 and anti-IL-15 significantly suppressed antigen-specific IFN-gamma production, while in ML only anti-IL-2 suppressed IFN-gamma production. Finally, higher frequency of CD4+ T cells expressing CD28-, CD69+ and CD62L(low) were observed in ML as compared to CL. These data indicate that an exacerbated type 1 response in ML is differentially regulated and not appropriately down modulated, with increased frequencies of activated effectors T cells, maintaining the persistent inflammatory response and tissue damage observed in ML. 相似文献
73.
74.
Darze ES Latado AL Guimarães AG Guedes RA Santos AB de Moura SS Passos LC 《Chest》2007,131(6):1838-1843
BACKGROUND: Congestive heart failure (CHF) is a well-recognized risk factor for venous thromboembolism (VTE) and is associated with higher mortality in patients with an acute pulmonary embolism (PE). There are very few data on how acute PE affects the clinical course of patients with heart failure. The purpose of this study was to determine the impact of an acute PE on the short-term prognosis of patients hospitalized for decompensated CHF. METHODS: This was a prospective cohort study of 198 patients admitted to a coronary care unit between July 2001 and March 2003 with severe decompensated CHF. The primary outcome measure was death or rehospitalization at 3 months. RESULTS: PE was confirmed in 18 of 198 patients enrolled (9.1%). The groups with and without PE were comparable with regards to demographics, the prevalence of comorbid conditions, and severity of CHF (p > 0.05). The prevalence of cancer (p = 0.0001), previous VTE (p = 0.003), and right ventricular overload (p = 0.006) was higher in the PE group. The presence of PE was also associated with a longer hospital stay (37.5 +/- 71.6 days vs 15.4 +/- 15.0 days, p = 0.001) [mean +/- SD] and a higher incidence of death or rehospitalization at 3 months (72.2% vs 43.9%, p = 0.02). In a multiple logistic regression analysis, PE remained an independent predictor of death or rehospitalization at 3 months (odds ratio, 4.0; 95% confidence interval, 1.1 to 15.1; p = 0.038). CONCLUSIONS: Acute PE commonly complicates the hospital course of patients with severe CHF, increasing the length of hospital stay and the chance of death or rehospitalization at 3 months. 相似文献
75.
Microarray-based gene expression analysis of human osteoblasts in response to different biomaterials
Bombonato-Prado KF Bellesini LS Junta CM Marques MM Passos GA Rosa AL 《Journal of biomedical materials research. Part A》2009,88(2):401-408
Several biomaterials have been widely used in bone regeneration/substitution procedures in orthopedic and oral surgery. However, how these biomaterials alter osteoblast gene expression is poorly understood. We therefore attempted to address this question by using cDNA microarray technique to identify genes that are differentially regulated in osteoblasts exposed to biomaterials comprehending the biocompatibility spectrum of bioactive (bioglass and hydroxyapatite), bioinert (Ti and stainless steel), and biotolerant (polymethylmethacrylate). By using a cDNA microarray containing 687 human IMAGE sequences, we identified in primary cultures of osteoblastic cells differentiated from the human bone marrow and exposed to these biomaterials, genes whose expression was significantly upregulated or downregulated. Among the differentially expressed genes we have found those involved with cell cycle regulation, cell differentiation and proliferation, apoptosis, cell adhesion, bone mineralization and skeletal development. These results can be relevant to a better understanding of the molecular mechanism underlying the behavior of osteoblasts in bone regenerative procedures. 相似文献
76.
77.
Passos SP Vanderlei AD Salazar-Marocho SM Azevedo SM Vasquez VZ Kimpara ET 《Acta odontológica latinoamericana : AOL》2010,23(2):79-83
This study examined the effect of 10% and 16% carbamide peroxide bleaching agents on the surface microhardness of micro-particulate feldspathic ceramics (VM7 and VM13, Vita Zahnfabrik). Forty specimens (8-mm diameter, 2-mm thickness) were divided into four groups (n=10): GI-VM7 + 10% Whiteness, G2-VM7 + 16% Whiteness, G3-VM13 + 10% and G4-VM13 + 16% Whiteness. The home-use bleaching agents were applied for 8 hours on 15 days, and the specimens were stored in distilled water at 37 degrees C. The Vickers hardness number (HV) was determined for each specimen. Data were analyzed by the Wilcoxon and Mann-Whitney tests (p < 0.05). The microhardness values before exposure were: g1-433 (57); g2-486 (22); g3-509 (28); g4-518 (24), and after exposure: G1-349 (32); G2-496 (95); G3-519 (38); G4-502 (81). G2 exhibited a higher and significant difference than GI in VM7 groups, and the effect of bleaching concentration was shown to be significant by the Mann-Whitney test. And for VM13, both the Wilcoxon and Mann-Whitney tests showed no significant differences. When using 10% carbamide peroxide, the microhardness of VM7 ceramic was affected, and there were no effect on the microhardness between VM7 and VM13 ceramics when 16% carbamide peroxide was used. 相似文献
78.
79.
Teivelis MP Faintuch J Ishida R Sakai P Bresser A Gama-Rodrigues J 《Arquivos de gastroenterologia》2007,44(1):8-13
BACKGROUND: Esophagogastric abnormalities are recognized prior and after bariatric procedures, but frequency and severity are debated. Liver and biliary tract findings are also of clinical importance, especially gallstones and liver steatosis. AIM: To compare pre-operative findings of hepatobiliary ultrasound and upper digestive endoscopy with post-operative results in patients submitted to open Roux-en-Y gastric bypass for morbid obesity. METHODS: A total of 80 patients were enrolled 16.8 +/- 12.1 months after operation, all of them on routine follow-up program, and 8 were excluded. Retrospective analysis aimed at pre-operative clinical, endoscopic and ultrasonographic examinations and were prospectively repeated. RESULTS: Pre-operative endoscopical report was available in 42 cases, and 52 examinations were performed post-operatively. Frequency of esophagitis changed from 16.7% (7/42) to 15.4% (8/52), and of gastritis from 45.2% (19/42) to 21.2% (11/52). Gastric or gastrojejunal ulcers were initially present in 4.8% (2/42) and increased to 9.6% (5/52). Post-operatively, an unusual abnormality was silastic band erosion: 7.7% (4/52). Helicobacter pylori was present in 50.0% (21/42) before and 3.5% (2/52) after operation. Ultrasonographic study had been done before intervention in 63 subjects, and 57 were executed on follow-up. Liver steatosis occurred previously in 58.7% (37/63) and in 43.9% (25/57) later on. Only 12.7% (8/63) of the patients had undergone cholecystectomy before bariatric operation, 29.1%(16/55) suffered simultaneous resection of gallbladder because of stones during Roux-en-Y gastric bypass, and an additional 26.8% (10/36) developed gallstones post-operatively. CONCLUSIONS: Liver steatosis did not statistically improve, nor did inflammatory conditions of the upper digestive tube, despite reduction of H. pylori infections; gallbladder stones requiring intervention were common. 相似文献
80.
Assessment of DNA damage in lymphocytes of workers exposed to X-radiation using the micronucleus test and the comet assay. 总被引:4,自引:0,他引:4
S W Maluf D F Passos A Bacelar G Speit B Erdtmann 《Environmental and molecular mutagenesis》2001,38(4):311-315
The mutagenic and carcinogenic effects of genotoxic agents on exposed people have constituted an increasing concern. Therefore, the objective of this work was to assess DNA damage in lymphocytes of workers exposed to X-radiation using the cytokinesis-blocked micronucleus test and the comet assay (single-cell gel electrophoresis), and to compare these two techniques in the monitoring of exposed populations. The cytokinesis-blocked micronucleus test and the comet assay were employed in the monitoring of 22 workers occupationally exposed to X-radiation in a hospital in southern Brazil. The frequency of dicentric bridges was also measured. The results of both assays and the frequency of dicentric bridges revealed a significant increase in genetic effects on the cells of exposed individuals. Age was significantly correlated with micronucleus frequency and damage index in the comet assay. The concomitant analysis of dicentric bridges when determining micronucleus frequency does not require much extra work, and may serve as a reference to the type of mutagenic effect (clastogenic or aneugenic). The combination of the alkaline comet assay with the cytokinesis-blocked micronucleus test appears to be very informative for the monitoring of populations chronically exposed to genotoxic agents. 相似文献