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91.
OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility.  相似文献   
92.
Access to good-quality health services is crucial for the improvement of many health outcomes, such as those targeted by the Millennium Development Goals (MDGs) adopted by the international community in 2000. The health-related MDGs cannot be achieved if vulnerable populations do not have access to skilled personnel and to other necessary inputs. This paper focuses on the geographical dimension of access and on one of its critical determinants: the availability of qualified personnel. The objective of this paper is to offer a better understanding of the determinants of geographical imbalances in the distribution of health personnel, and to identify and assess the strategies developed to correct them. It reviews the recent literature on determinants, barriers and the effects of strategies that attempted to correct geographical imbalances, with a focus on empirical studies from developing and developed countries. An analysis of determinants of success and failures of strategies implemented, and a summary of lessons learnt, is included.  相似文献   
93.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
94.
We developed a self-administered questionnaire for screening the most common adult-onset dystonias. It was tested in 90 first-degree relatives of 22 adult-onset dystonia patients, yielding 79% sensitivity and 94% specificity. Simulation of a case-finding procedure based on serial application of the questionnaire and clinical examination of both subjects screening positive and subjects screening negative who had < 8 years of schooling increased sensitivity to 95% and specificity to 100%. This questionnaire may be an important screening resource for familial aggregation studies to be used in the context of a complex case-finding procedure.  相似文献   
95.
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex.  相似文献   
96.
Although renal dysfunction is common after liver transplantation, postoperative renal function after split liver transplantation (SLT) has not been well studied. Renal function immediately after surgery was analyzed retrospectively in 16 patients that received a SLT (SLT group). The results were compared with corresponding data from 31 matched patients that received a full-size liver transplant (FSLT group) during the same period. Serum creatinine (SCr) was measured before surgery, and, after transplantation, daily during the first week and at days 14, 21, and 28. Renal dysfunction (RD) was defined as the requirement for renal replacement therapy (RRT) or a 100% increase in SCr if the basal value had been <1.0 mg/dL or a 50% increase in SCr if the basal value had been >1.0 mg/dL. SCr had to be at least 1.5 mg/dL for a diagnosis of RD to be considered. The classification of RD was: mild, SCr 1.5-2.4 mg/dL; moderate, SCr 2.5-4.0 mg/dL; or severe, SCr >4.0 mg/dL (the requirement for RRT). Both donor and recipient age and cold ischemia time were lower in the SLT group than in the FSLT group (P < 0.05). Length of surgery was longer in the SLT group (P < 0.05). There were no significant differences between groups with respect to Model for End-Stage Liver Disease scores, the need for transfusions, the length of admission to the intensive care unit (ICU), survival rate, individual severity index, or sepsis-related organ failure assessment scores at the time of diagnosing RD. Immunosuppression regimens were similar in both groups. RD developed in 82% of SLT patients, but in only 58% of FSLT patients (P = not significant [NS]). Among SLT patients, RD (23.0% mild, 15.5% moderate, and 61.5% severe) was more severe (P = 0.007) than in FSLT patients (63.1% mild, 15.8% moderate, and 24.1% severe). The requirement for RRT in the SLT group (43.7%) was significantly greater (P < 0.05) than that in the FSLT group (12.9%). This finding may be due to the different incidence of sepsis in the 2 groups (SLT 37.5% vs. FSLT 9.7%; P < 0.05). In conclusion, although the number of patients studied was small, our data suggest a higher incidence of RD and a greater requirement for RRT in patients that receive a split liver graft than in those that receive a full size liver graft.  相似文献   
97.
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members.  相似文献   
98.
99.
BACKGROUND: Oral hairy leukoplakia (OHL) may be an indicator of the progression of Human Immunodeficiency Virus (HIV)-induced immuno-depression, and the evaluation of risk factors leading to OHL is important in the management of these HIV-infected patients. However, there are few studies that analyze risk factors leading to OHL in the Brazilian population. The aim of this case-control study is to present data about prevalence rates and risk factors leading to OHL in a sample of HIV-infected adults in Brazil. METHODS: This case-control study included 111 HIV-infected patients treated at a clinic for sexually transmitted diseases and HIV. In the initial examinations with dentists, variables were collected from all patients. Diagnosis of OHL was performed in accordance with the International Classification System and cytological features. The Fisher and the chi-squared tests were used for statistical analysis. The proportional prevalence and odds ratio were estimated. RESULTS: Outcome presented a positive, statistically significant association among the presence of OHL and viral load of 3000 copies/mul or greater (P = 0.0001; odds ratio (OR) = 5.8), presence of oral candidiasis (P = 0.0000; OR = 11.1), previous use of fluconazole (P = 0.0000; OR = 24.6), and use of systemic acyclovir (P = 0.032; OR = 4.3). Antiretroviral medication presented a negative, statistically significant association with the presence of OHL (P = 0.002; OR = 8.4). CONCLUSIONS: Prevalence of OHL was 28.8%. Viral load, oral candidiasis, previous use of fluconazole, and systemic acyclovir were determined to be risk factors for OHL. Antiretroviral medication proved to be protective against the development of OHL.  相似文献   
100.
BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD.  相似文献   
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