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91.
92.
The efficacy of ultrasound in removing cast metal posts was evaluated in this in vitro study using one or two ultrasound units and ultrasonic vibration for various lengths of time. The crowns of 30 healthy maxillary canines were removed, the roots were embedded in acrylic resin blocks, and the root canals were treated endodontically. The canals were prepared and their impressions were taken with self-curing acrylic resin. After casting with copper-aluminum alloy, the posts were blasted with aluminum oxide and cemented with Panavia F resin cement. The specimens were divided into five groups. In groups I and II, only one ultrasound unit was used for 30 and 60 s, respectively; in groups III and IV, two ultrasound units were used simultaneously for 30 and 60 s, respectively; in group V, ultrasound was not used (control). Ultrasonic vibrations were applied with an Enac OE-5 ultrasound unit and an ST-09 tip. All samples were subjected to traction on an Instron machine (model 4444) at a cross-head speed of 1 mm/min. Analysis of the results revealed a statistically significant difference between the groups (ANOVA, P < 0.01); however the difference between groups II and IV was not statistically significant. The efficacy of ultrasound in removing intraradicular posts was confirmed, and the most effective technique was the use of two ultrasound units, independent of the length of time ultrasound was applied.  相似文献   
93.
Apert syndrome is characterized by craniosynostosis, symmetric syndactyly and other systemic malformations, with mental retardation usually present. The objective of this study was to correlate brain malformations and timing for surgery with neuropsychological evaluation. We also tried to determine other relevant aspects involved in cognitive development of these patients such as social classification of families and parents education. Eighteen patients with Apert syndrome were studied, whose ages were between 14 and 322 months. Brain abnormalities were observed in 55.6% of them. The intelligence quotient or developmental quotient values observed were between 45 and 108. Mental development was related to the quality of family environment and parents education. Mental development was not correlated to brain malformation or age at time of operation. In conclusion, quality of family environment was the most significant factor directly involved in mental development of patients with Apert syndrome.  相似文献   
94.
Status Dystonicus (SD) is characterized by generalized muscle contractions in dystonic patients. We report 5 cases of SD, two of which in patients with dystonic cerebral palsy, one in a patient with primary segmental dystonia, one in a patient with Hallervorden-Spatz syndrome and one in a patient with Wilson's disease (WD). Three patients were admitted to an intensive care unit and treated with propofol and midazolam, and two were submitted to neurosurgical procedures (bilateral pallidotomy and bilateral pallidal deep brain stimulation). Triggering factors were identified in three patients as follows: infection, stress-induced and zinc therapy for WD. On follow-up, two patients presented with significant improvement of dystonia, whereas the other three cases the clinical picture ultimately returned to baseline pre-SD condition.  相似文献   
95.
To study the prevalence of connective tissue disorders and identify the epidemiological profile of the population from the northern and northeastern regions of Brazil. All patients admitted to the general medical ward at Getulio Vargas Hospital were screened through history and physical examination for the existence of known, suspected or possible connective tissue disorder. A total of 120 patients were enrolled in the study - 61 (50.8%) with systemic lupus erythematosus (SLE), 41 (34.2%) with rheumatoid arthritis (RA), 16 (13.3%) with systemic sclerosis (SS), one (0.8%) with mixed connective tissue disease (MCTD) and one (0.8%) with polymyositis (PM). Women accounted for (104) 86.7% of the participants and (83) 70.9% were non-Caucasians. The mean age was 36.8 years. Alopecia was the most frequent symptom (55/46.6%), followed by other cutaneous lesions (50/42.4%), dyspnea (47/39.8%) and chest pain (39/33.0%). The most frequent rheumatologic disorder encountered in our hospital-based study population was systemic lupus erythematosus, which is contrary to findings of the majority of studies performed in this country.  相似文献   
96.
97.
Liver transplantation with monosegment from a living donor   总被引:3,自引:0,他引:3  
The shortage of organ donors for low-weight liver transplant recipients, especially for small children, has led to the development of new surgical techniques to increase the donor pool. Almost all of these techniques use the left lateral segment (Couinaud's segments II and III), but even this graft could be too large for children under 10 kg. We report here the case of an 8-month-old boy, weighing 6.1 kg, who received a monosegmental graft (segment III) from his grandmother weighing 68 kg. The graft was reduced at the donor surgery, before clamping of the vessels. The donor was discharged on the fourth post-operative day; the recipient had an uneventful post-operative period and was discharged after 22 days.  相似文献   
98.
This study aims to offer a historical overview of the emergence and evolution of group psychotherapy, tracing its roots, main models and theoretical bases. Its origin goes back to the beginning of the past century (1905), after which it evolved for five decades: the formative years. Further on, during the 50's and 60's, group psychotherapy went through a period of theoretical expansion, followed by a period of consolidation in the 70's, and maturation in the 80's and 90's. Finally, the study examines its recent evolution, highlighting the construction of new models. In the last few years, several treatment techniques have been developed to attend specific patient populations, with a variety of medical and psychosocial conditions, which suggests an increasing tendency towards a greater specificity of its application.  相似文献   
99.
Numerous factors have been studied to establish more secure prognostic criteria in breast cancer patients. This study estimates five-year survival rates and principal prognostic factors related to tumor characteristics in women with invasive breast cancer and submitted to surgery at the National Cancer Institute, Rio de Janeiro, Brazil, from May 1995 to July 1996. Study variables were: lymph node status, tumor size, aggressiveness grade, and presence of estrogen and progesterone receptors. Survival functions were calculated according to the Kaplan-Meyer method. The Cox proportional hazards model was used to evaluate prognostic factors. Five-year survival was 75% for all women and 64% for those with node involvement. Multivariate analyses identified node involvement as the strongest predictor of outcome; a positive estrogen receptor test was associated with a better prognosis. These findings highlight the need for studies to assess new variables to be added to known factors in order to better orient therapy for breast cancer.  相似文献   
100.
Apert Syndrome, also called acrocephalosyndactylia type 1, is characterized by craniostenosis with early fusion of sutures of the vault and/or cranial base, associated to mid-face hypoplasia, symmetric syndactylia of the hands and feet and other systemic malformations. CNS malformations and intracranial hypertension are frequently observed in these patients. Early surgical treatment aims to minimize the deleterious effects of intracranial hypertension. Fronto-orbital advancement, the usual surgical technique, increases the intracranial Volume and improves the disposition of encephalic structures previously deformed by a short skull. This study analyzes CNS alterations revealed by magnetic resonance in 18 patients presenting Apert Syndrome, and the conformational alterations in the encephalic structures after surgical treatment. The patients' age in February 2001 ranged from 14 to 322 Months (m=107). Image study included brain magnetic resonance showing ventricular enlargement in five cases (27.8%), corpus callosum hypoplasia in five cases (27.8%), septum pellucidum hypoplasia in five cases (27.8%), cavum vergae in two cases (11.1%) and, arachnoid cyst in the posterior fossa in two cases (11.1%). Absence of CNS alterations was noted in 44.4% of cases. A corpus callosum morphologic index was established by dividing its height by its length, which revealed values that ranged from 0.4409 to 1.0237. The values of this index were correlated to the occurrence or absence of surgical treatment (p=0.012; t=2.83). Data analysis allowed the conclusion that the corpus callosum morphologic measure quantified the conformational alterations of the cerebral structures determined by the surgical treatment.  相似文献   
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