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91.
Age changes affect the oral mucosa (the protective lining of the oral cavity), but few of these have been studied objectively. The aim of this study was to quantitatively analyse a number of morphometric parameters of the ageing oral mucosa. The fractal dimension of the epithelial connective tissue interface (ECTI) was estimated in 42 samples of normal buccal mucosa to correlate any changes in their irregularity to the age of the individuals. Morphometric parameters extracted from theoretical cell areas computed programatically were also analysed. Results showed no significant change in ECTI complexity associated with age; however, there was indication that epithelial cells tended to become larger and flatter with age. Interestingly, while some parameters did not show significant differences case wise, cluster analysis showed that the data clustered the cases into three main age groups: one representing the first two decades of life, another group represents adult life (21–50 years) and the last group representing the ageing population (50–90 years).  相似文献   
92.
The aim of this study was to assess the three-dimensional soft tissue changes following anterior segmental maxillary osteotomy, in terms of magnitude and direction in correlation to hard tissue changes, using cone beam computed tomography (CBCT). The study included 6 patients (age range 17-35 years) suffering from dental maxillary protrusion that required surgical correction by anterior segmental maxillary osteotomy. For each patient, preoperative and postoperative CBCT, photographs, and orthodontic casts were taken before and 6 months after operation to analyse soft tissue changes, in terms of magnitude and direction in correlation to hard tissue changes, using linear and angular measurements. Hard and soft tissue changes were only observed in the maxillary region, upper lip area and nasal tip. Soft tissue mean change included 53% backward displacement of the labrale superius in relation to bone displacement and 18.7% mean increase in the naso-labial angle. The highest correlation coefficient was obtained between the hard and soft tissue changes in the upper lip region. Anterior segmental maxillary osteotomy might be recommended as the treatment modality of choice in patients with maxillary or dento-alveolar protrusion, the technique is simple, safe, and postoperative complications are minimal.  相似文献   
93.
The aim of this study was to compare two different types of surgical approaches, intrasinus and extramaxillary, for the placement of zygomatic implants to treat atrophic maxillae. A computational finite element simulation was used to analyze the strength of implant anchorage for both approaches in various occlusal loading locations. Three-dimensional models of the craniofacial structures surrounding a region of interest, soft tissue and framework were developed using computed tomography image datasets. The implants were modelled using computer-aided design software. The bone was assumed to be linear isotropic with a stiffness of 13.4GPa, and the implants were assumed to be made of titanium with a stiffness of 110GPa. Masseter forces of 300N were applied at the zygomatic arch, and occlusal loads of 150N were applied vertically onto the framework surface at different locations. The intrasinus approach demonstrated more satisfactory results and could be a viable treatment option. The extramaxillary approach could also be recommended as a reasonable treatment option, provided some improvements are made to address the cantilever effects seen with that approach.  相似文献   
94.
Data on minimal residual disease (MRD) monitoring in acute promyelocytic leukemia (APL) are available only in the context of conventional all-trans retinoic acid plus chemotherapy regimens. It is recognized that the kinetics of leukemia clearance is different with the use of arsenic trioxide (ATO) in the treatment of APL. We undertook a prospective peripheral blood RT-PCR-based MRD monitoring study on patients with APL treated with a single agent ATO regimen. A total of 151 patients were enrolled in this study. A positive RT-PCR reading at the end of induction therapy was significantly associated on a multivariate analysis with an increased risk of relapse (relative risk = 4.9; P = .034). None of the good risk patients who were RT-PCR negative at the end of induction relapsed. The majority of the relapses (91%) happened within 3 years of completion of treatment. After achievement of molecular remission, the current MRD monitoring strategy was able to predict relapse in 60% of cases with an overall sensitivity and specificity of 60% and 93.2%, respectively. High-risk group patients and those that remain RT-PCR positive at the end of induction are likely to benefit from serial MRD monitoring by RT-PCR for a period of 3 years from completion of therapy.  相似文献   
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96.
The study determined how spatiotemporal distribution of cortical activity to words in first and second language is affected by language, proficiency, and linguistic setting. Ten early bilinguals and 14 late adult bilinguals listened to pairs of words presented in Arabic (L1), Hebrew (L2), or in mixed pairs and indicated whether both words had the same meaning or not. Source current densities of event‐related potentials were estimated. Activity to first words in the pair lateralized to right hemisphere, higher to L1 than L2 during early processing (<300 ms) among both groups but only among late bilinguals during late processing (>300 ms). During early and late processing, activities were larger in mixed than monolinguistic settings among early bilinguals but lower in mixed than in monolinguistic settings among late bilinguals. Late processing in auditory regions was of larger magnitude in left than right hemispheres among both groups. Activity to second words in the pair was larger in mixed than in monolinguistic settings during both early and late processing among both groups. Early processing of second words in auditory regions lateralized to the right among early bilinguals and to the left among late bilinguals, whereas late processing did not differ between groups. Wernicke's area activity during late processing of L2 was larger on the right, while on the left no significant differences between languages were found. The results show that cortical language processing in bilinguals differs between early and late processing and these differences are modulated by linguistic proficiency and setting. Hum Brain Mapp 34:2863–2881, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
97.
Narasin poisoning was reported in 15 camels, 7 adults and 8 young, after accidental access to poultry feed medicated with 60 g narasin per ton. Fourteen camels died between 3 and 20 days, and one young animal survived the dose after developing a chronic course of a disease. The main clinical signs of narasin toxicity in the dromedary include: weakness of hind limbs, lack of coordination, oedema of dependent parts, inappetence, ruminal atony, myoglobinuria, profound depression, tachycardia, sternal recumbency and death. The lesions were mainly in the heart and skeletal muscles and consisted of multifocal degeneration and necrosis of heart and skeletal muscle fibres with areas of regeneration and lung oedema. There was high enzyme activity for creatine kinase (CK), lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase and an increase in urea concentration and white blood cells, neutrophil and platelet counts. Cardiac markers, troponin T, CK-MB and C-reactive protein, showed slight or no changes terminally.  相似文献   
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Ethylmalonic encephalopathy (EE) is a rare autosomal recessive disorder caused by mutations in the ETHE1 gene and characterized by chronic diarrhea, encephalopathy, relapsing petechiae and acrocyanosis. Nephrotic syndrome has been described in an infant with EE but the renal histology findings were not described in previous reports. We report a Palestinian girl with EE who presented with chronic diarrhea, encephalopathy, petechial rash and acrocyanosis. Subsequently, she developed progressive deterioration of renal function caused by rapidly progressive glomerulonephritis resulting in death within few days. This is, to our knowledge, the first reported occurrence of rapidly progressive glomerulonephritis in a child with ethylmalonic encephalopathy. Its presence is a serious complication associated with poor prognosis and may be explained by the diffuse vascular damage  相似文献   
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