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991.
Data regarding the biologic behavior and surgical management, in particular the axillary lymph node excision, of ductal carcinoma in situ with microinvasion (DCIS-MI) are controversial. Therefore, we decided to study the histopathologic characteristics, the biopathologic profile, as well as the follow-up of a group of patients with DCIS-MI. Thirty-one cases of DCIS-MI, 21 of whom were treated with axillary lymph node dissection, were studied. All cases were classified according to the Van Nuys classification, and the extension of DCIS was quantified. The biopathologic profile (ER, PR, MIB 1, p53, c-erbB-2) as well as the follow-up was also investigated. The results did not reveal any statistically significant differences between the two groups, and there was no statistically significant relationship between the extension of DCIS and the number of microinvasion (MI) foci or maximum MI diameter, or between Van Nuys classification of DCIS and again the number of MI foci or maximum MI diameter. DCIS-MI seems associated with good prognosis. None of the patients had relapses or metastases. Our data seem to suggest that the natural history of DCIS-MI resembles DCIS, and we, therefore, suggest that all the surgically removed area should be examined histologically to avoid missing foci of infiltrating breast cancer larger than 1mm.  相似文献   
992.
The aim of the present study was to evaluate whether it is possible to orthodontically move migrated teeth into infrabony defects augmented with a biomaterial. Three adult patients suffering from chronic periodontitis were treated. Each of the patients presented with an infrabony defect adjacent to a migrated maxillary central incisor. After cause-related therapy was completed, a surgical procedure was performed using the papilla preservation technique. The defects were filled with a collagen bovine bone mineral; after 2 weeks, an orthodontic device was activated using light, continuous forces. Orthodontic treatment time varied from 4 to 9 months; during this period, patients were enrolled in an oral hygiene recall program. At baseline and 6 months after the end of therapy, probing pocket depths (PPD) and clinical attachment levels (CAL) were assessed. In addition, the vertical and horizontal dimensions of the defects were measured on standardized radiographs. Residual mean PPD was 3.33 mm, with a mean reduction of 3.67 mm. Mean CAL gain was 4.67 mm. Radiologic vertical and horizontal bone fills were, on average, 3.17 mm and 2.0 mm, respectively. The present case series shows the effectiveness of a combined periodontic-orthodontic approach for the treatment of infrabony defects. Reduction of PPD to physiologic values, CAL gain, and radiologic defect resolution were obtained. No detrimental effects from the orthodontic movement were observed on the augmentation material.  相似文献   
993.
994.
Association between hormones and metabolic syndrome in older Italian men   总被引:2,自引:0,他引:2  
OBJECTIVES: To determine whether low levels of testosterone, sex hormone binding globulin (SHBG), insulin-like growth factor-1 (IGF-1), and dehydroepiandrosterone sulfate (DHEAS) and high levels of cortisol and leptin would be associated with metabolic syndrome (MS). DESIGN: Cross-sectional. SETTING: Population-based sample of older Italian men. PARTICIPANTS: Four hundred fifty-two men aged 65 and older enrolled in the Invecchiare in Chianti (InCHIANTI) study. MEASUREMENTS: Complete data on testosterone, cortisol, DHEAS, SHBG, fasting insulin, IGF-1 and leptin. MS was defined according to Adult Treatment Panel III criteria. RESULTS: MS was present in 73 men (15.8% of the sample). After adjusting for confounders, total testosterone (P < .05) and log (SHBG) (P < .001) were inversely associated, whereas log (leptin) was positively associated with MS (P < .001). Independent of age, log (SHBG) was positively associated with high-density lipoprotein cholesterol (P < .05) and negatively associated with abdominal obesity (P < .001) and triglycerides (P < .001). Log (leptin) was significantly associated with each component of MS. Cortisol, DHEAS, free and bioavailable testosterone, and IGF-1 were not associated with MS. Having three or more hormones in the lower (for hormones lower in MS) or the upper (for hormones higher in MS) quartile was associated with three times the risk of being affected by MS (odds ratio = 2.8, 95% confidence interval = 1.3-6.9) (P = .005), compared with not having this condition. CONCLUSION: Total testosterone and SHBG are negatively and leptin is positively associated with MS in older men. Whether specific patterns of hormonal dysregulation predict the development of MS should be tested in longitudinal studies.  相似文献   
995.
Aspirin affords cardioprotection through the acetylation of serine529 in human cyclooxygenase-1 (COX-1) of anucleated platelets, inducing a permanent defect in thromboxane A2 (TXA2)-dependent platelet function. However, heterogeneity of COX-1 suppression by aspirin has been detected in cardiovascular disease and may contribute to failure to prevent clinical events. The recent recognized capacity of platelets to make proteins de novo paves the way to identify new mechanisms involved in the variable response to aspirin. We found that in washed human platelets, the complete suppression of TXA2 biosynthesis by aspirin, in vitro, recovered in response to thrombin and fibrinogen in a time-dependent fashion (at 0.5 and 24 hours, TXB2 averaged 0.1+/-0.03 and 3+/-0.8 ng/mL; in the presence of arachidonic acid [10 micromol/L], it was 2+/-0.7 and 25+/-7 ng/mL, respectively), and it was blocked by translational inhibitors, by rapamycin, and by inhibitors of phosphatidylinositol 3-kinase. The results that COX-1 mRNA was readily detected in resting platelets and that [35S]-methionine was incorporated into COX-1 protein after stimulation strongly support the occurrence of de novo COX-1 synthesis in platelets. This process may interfere with the complete and persistent suppression of TXA2 biosynthesis by aspirin necessary for cardioprotection.  相似文献   
996.
The aim of this study was to explore the relationship among components of the metabolic syndrome and their role in the development of diabetes. We included 2295 subjects, aged 65-84 years, participating in the Italian Longitudinal Study on Aging, a population-based study conducted in 1992 and with a follow-up in 1996. Factor analysis was conducted, separately for diabetic and non-diabetic men and women, using the principle components method and varimax rotations. Factor scores for the baseline were used as independent variables in logistic regressions models to determine risk factors predicting the development of diabetes. Factor analysis among non-diabetic elderly showed two factors for men (body size/insulin resistance, blood pressure/lipids) and three for women (body size, lipids, blood pressure). Among diabetic subjects, three factors emerged for men (body size/lipids/insulin resistance, body size/blood pressure, glucose) and four for women (body size/lipids/insulin resistance, lipids, body size/glucose/insulin resistance, lipids/blood pressure). For non-diabetic men and women, the body size factor (body size/insulin resistance factor for men) was strongly associated with diabetes incidence (OR=2.30, 95% CI 1.41-3.74 and OR=2.06, 95% CI 1.33-3.17, respectively). This study confirms that the metabolic syndrome (MetS) does not recognize one single underlying factor in an elderly cohort and that the obesity factor is a strong predictor of development of new onset diabetes.  相似文献   
997.
998.
999.
beta-D-2'-Deoxy-2'-fluoro-2'-C-methylcytidine (PSI-6130) is a cytidine analogue with potent and selective anti-hepatitis C virus (HCV) activity in the subgenomic HCV replicon assay, 90% effective concentration (EC90)=4.6 +/- 2.0 microM. The spectrum of activity and cytotoxicity profile of PSI-6130 was evaluated against a diverse panel of viruses and cell types, and against two additional HCV-1b replicons. The S282T mutation, which confers resistance to 2'-C-methyl adenosine and other 2'-methylated nucleosides, showed only a 6.5-fold increase in EC90. When assayed for activity against bovine diarrhoea virus (BVDV), which is typically used as a surrogate assay to identify compounds active against HCV, PSI-6130 showed no anti-BVDV activity. Weak antiviral activity was noted against other flaviviruses, including West Nile virus, Dengue type 2, and yellow fever virus. These results indicate that PSI-6130 is a specific inhibitor of HCV. PSI-6130 showed little or no cytotoxicity against various cell types, including human peripheral blood mononuclear and human bone marrow progenitor cells. No mitochondrial toxicity was observed with PSI-6130. The reduced activity against the RdRp S282T mutant suggests that PSI-6130 is an inhibitor of replicon RNA synthesis. Finally, the no-effect dose for mice treated intraperitoneally with PSI-6130 for six consecutive days was > or =100 mg/kg per day.  相似文献   
1000.
To favor bone reconstitution with biomaterials endothelial cells should maintain proper functions to drive angiogenesis. To this aim nanocrystals of hydroxyapatite (HA) have been synthesized and characterized on endothelial cells. Microvascular endothelial cells have been exposed to stoichiometric HA nanocrystals. Cell morphology and organization of cytoskeletal proteins have been monitored by SEM analysis and immunofluorescence. Biochemical markers of physiological and pathological responses of endothelial cells, endothelial constitutive nitric oxide synthase, and cycloxygenase-2 (ecNOS and COX-2, respectively) have been measured by immunofluorescence. Crystallized HA sustained endothelial survival without any cytotoxic effect. At the observation with SEM, endothelial cell morphology was maintained in the presence of HA. The localization and organization of beta-actin documented the formation of stress fibers, indicating an activation of endothelial cells induced by HA nanocrystals. Immunohistochemistry for biochemical key signaling pathways in endothelium demonstrated that nanocrystals of HA maintained the expression of ecNOS and did not increase COX-2 expression. In conclusion, the present findings indicate that HA nanocrystals exhibit high biocompatibility for microvascular endothelium. In the presence of HA nanocrystals endothelial cells maintain biochemical markers of healthy endothelium. They do not acquire a proinflammatory or thrombogenic phenotype, but express markers of functioning endothelium that might contribute to angiogenesis.  相似文献   
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