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Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P  = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI.  相似文献   
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We evaluated the expression of T cell-restricted intracellular antigen (Tia-1), granzyme B, and perforin by lymphocytes and the degree of epithelial apoptosis in oral and cutaneous lichen planus (LP) in 51 untreated cases, including 27 oral LP (OLP) and 24 cutaneous LP (CLP) cases. The number of total dermal-positive lymphocytes in OLP and CLP was similar, indicating similar activity of the inflammatory process. Intraepithelial Tia-1-positive, perforin-positive, and granzyme B-positive lymphoid cells were more numerous in OLP than in CLP (P < .05). The epithelial cell apoptotic index (AI) was increased significantly in OLP (P < .05), particularly in erosive-atrophic variants. A linear correlation between AI and the mean +/- SEM number of intraepithelial and dermal perforin+ cells (6.85 +/- 2.44 and 27.48 +/- 10.19, respectively), per 10 high-power fields for OLP and for CLP (1.17 +/- 0.88 and 10.42 +/- 5.74, respectively), was found (intraepithelial, r = 0.50; dermal, r = 0.51; P < .01). These data suggest a pivotal role for perforin in triggering epithelial cell apoptosis. The differences of infiltrating cytotoxic cells and related AI observed in OLP and CLP are in keeping with the clinical behaviors that distinguish these LP variants.  相似文献   
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Clementi  M.  Testa  I.  Bagnarelli  P.  Festa  A.  Pauri  P.  Brugia  M.  Calegari  L.  de Martinis  C. 《Archives of virology》1984,81(1-2):177-184
Summary Although its action at the molecular level is not completely understood, insulin, as well as its antagonist glucagon, certaily plays an important role in the modulation of protein synthesis.In order to observe whether insulin is involved in virus gene expression, we studied its effect on PLC/PRF/5 human hepatoma cell line, which posses HBV DNA sequences integrated at several sites.While human insulin had no effect on cell growth and increased the production of two plasma proteins, a selective inhibitory effect on HBsAg production could be detected.This observation might be useful for further studies both on virus gene expression and insulin action at the molecular level.With 3 Figures  相似文献   
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Several structural parameters of the capillary vessels were measured in the oral mucosa of patients with diabetes mellitus of type 1 (D.1) and of type 2 (D.2), and of control cases (C), by means of an image analyser in histological sections of routinely processed biopsies. The studied parameters included: a) capillary wall thickness; b) capillary diameter; c) the ratio of capillary wall thickness and diameter; d) capillary wall area; e) capillary area; f) the ratio of capillary wall area and capillary area; g) density of capillary vessels in the lamina propria; h) density of endothelial cells; i) endothelial nuclear area. Clinical and laboratory parameters were also evaluated (duration of the disease, systolic and diastolic blood pressure levels, glycemia, glycosylated haemoglobin, glycosylated albumin, fructosamines, apolipoproteins A1 and B), in order to assess whether a relationship exists with the morphometric parameters studied. Statistically significant differences, at the level of p less than 0.05, were found in the following morphometric parameters between controls and each group of diabetic patients: mean and standard deviation of capillary wall thickness, mean capillary wall area, mean ratio of the capillary wall area and capillary area. A reduction in the capillary density, i.e. the number of capillary vessels per mm2 of lamina propria, was also observed in diabetic patients with respect to the control group, although it was not statistically significant (C vs. D.1: p less than 0.21; C vs. D.2: p less than 0.10).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Central chemoreceptors and sympathetic vasomotor outflow   总被引:1,自引:1,他引:1  
The present study explores how elevations in brain   P CO2  increase the sympathetic nerve discharge (SND). SND, phrenic nerve discharge (PND) and putative sympathoexcitatory vasomotor neurons of the rostral ventrolateral medulla (RVLM) were recorded in anaesthetized sino-aortic denervated and vagotomized rats. Hypercapnia (end-expiratory CO2 from 5% to 10%) increased SND (97 ± 6%) and the activity of RVLM neurons (67 ± 4%). Injection of kynurenic acid (Kyn, ionotropic glutamate receptor antagonist) into RVLM or the retrotrapezoid nucleus (RTN) eliminated or reduced PND, respectively, but did not change the effect of CO2 on SND. Bilateral injection of Kyn or muscimol into the rostral ventral respiratory group (rVRG-pre-Bötzinger region, also called CVLM) eliminated PND while increasing the stimulatory effect of CO2 on SND. Muscimol injection into commissural part of the solitary tract nucleus (commNTS) had no effect on PND or SND activation by CO2. As expected, injection of Kyn into RVLM or muscimol into commNTS virtually blocked the effect of carotid body stimulation on SND in rats with intact carotid sinus nerves. In conclusion, CO2 increases SND by activating RVLM sympathoexcitatory neurons. The relevant central chemoreceptors are probably located within or close to RVLM and not in the NTS or in the rVRG-pre-Bötzinger/CVLM region. RVLM sympathoexcitatory neurons may be intrinsically pH-sensitive and/or receive excitatory synaptic inputs from RTN chemoreceptors. Activation of the central respiratory network reduces the overall sympathetic response to CO2, presumably by activating barosensitive CVLM neurons and inhibiting RTN chemoreceptors.  相似文献   
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Lasers in Medical Science - This study compared the effects of LED therapy associated with occlusal splint (OS) on the signs and symptoms of temporomandibular disorder (TMD). In this randomized,...  相似文献   
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BackgroundMultivisceral transplant (MVTx) and isolated intestinal transplant (ITx) are complex surgical procedures. The subsequent proinflammatory state in the immediate postoperative period makes interpretation of blood markers difficult.MethodWe aimed to establish the course of various blood markers after MVTx/ITx, and to evaluate their use as diagnostic markers of complications. This was a single center prospective cohort. We analyzed blood markers collected preoperatively, on alternate days for the first postoperative week, and then weekly for 4 weeks. This study was in compliance with The Declaration of Helsinki.ResultsOver a 16-month period (July 2017-October 2018), 20 subjects aged 2 to 67 years with a median age of 24.5 years received MVTx/ITx. Twelve recipients (60%) had an infection. Neutrophil lymphocyte count ratio (NLCR) was higher than established upper limits of normal, regardless of infection status. NLCR and white blood cell count were useful to identify infected MVTx/ITx recipients, with P values <.05 for 2 and 1 of 7 time points post transplant, respectively. Higher preoperative eosinophil% predicted future acute cellular rejection (P value .023).ConclusionsThis is the first study to extensively track the course of blood markers post MVTx/ITx and identified NLCR and white blood cell count as potential diagnostic blood markers of infection.  相似文献   
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