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Purpose: This controlled clinical trial aimed to compare the 3-year outcomes of glass fiber posts and composite cores with gold alloy-based posts and cores for the restoration of endodontically treated teeth. Materials and Methods: One hundred forty-four patients in need of 205 restorations on endodontically treated teeth were selected and followed for 7 to 37 months (mean: 21 ± 9 months). The teeth were primarily stratified based on the remaining tissue available to restore the tooth core with or without a post. Then, randomization allocated the teeth to either test group 1 (prefabricated glass fiber posts), test group 2 (custom-made glass fiber posts), or test group 3 (composite cores without posts). The control group consisted of gold alloy-based posts and cores. All posts/cores were covered with all-ceramic single crowns. Failures were either absolute, such as root fractures or irreparable fractures of the post/core, or relative, such as loss of post retention or reparable fractures of the core. Success and survival probability lifetime curves, corrected for clustering, were drawn for the entire data set. Results: The recall rate at 3 years was 97.1%. Absolute failures consisted of two root fractures and one endodontic failure, while relative failures included three instances of retention loss of the post/core and one post fracture. Because of the low number of events, no statistical tests were performed. The success and survival probabilities over all groups together at 3 years amounted to 91.7% and 97.2%, respectively. Conclusions: After being followed for up to 3 years, both cast gold and composite post and core systems performed well clinically. Longer follow-up times are needed to detect possible significant differences. Int J Prosthodont 2011;24:363-372.  相似文献   
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Intraoperative ultrasonography (I.US) has been introduced in order to overcome the limits of the preoperative imaging modalities (notably, ultrasonography and computed tomography), both in pancreatic cancer diagnosis and staging. The authors' experience encompasses 32 cases, selected according to the following criteria: lesions that could not be detected both preoperatively and at surgical exploration; lesions detected but not properly characterized, requiring differential diagnosis between cancer and pancreatitis; tumoral lesions with a perspective of radical surgery, in which the preoperative judgment of resectability had to be verified. In the only case of the first group, I.US allowed the identification of a small cancer in a jaundiced patient. In the 11 cases of the second group, I.US-guided fine-needle aspiration biopsy showed three cancers; however, among the other 8 lesions classified as pancreatitis there was one false negative diagnosis (a tumoral mass with liver metastases was demonstrated by computed tomography 6 mo later). Regarding the intraoperative staging of the proven cancers (20 cases of the third group; 4 cases of the first and second groups), I.US changed the planned surgical approach in 9 cases (showing vascular involvement or detecting liver metastases and enlarged lymph nodes not seen preoperatively); in 12 cases it confirmed the possibility of radical surgery. Finally, in the remaining 3 cases, I.US provided dubious information: only vascular dissection during surgery could achieve a correct evaluation, ruling out vascular involvement and thus allowing tumor resection.  相似文献   
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A simple exercise test would be useful for detecting exercise-induced asthma, a common problem in asthmatic children. The current study compared the 3-min step test with treadmill exercise for evaluating exercise-induced asthma in asthmatic children and assessed whether responses to both tests are influenced by baseline lung function and habitual physical activity. A series of 154 asthmatic children (84 male children; mean age 12.9 +/- 0.9 yrs) underwent a 3-min step-test and treadmill testing on different days within a week at least 24 h apart. Before both tests each subject did spirometry to obtain the baseline forced expiratory volume in one second (FEV1). After both exercise challenges all subjects did serial spirometry and the lowest FEV1 recorded over time was used to calculate the fall in FEV1 expressed as a percentage of the measured pre-exercise (baseline) value (% fall in FEV1) and the area above the FEV1 curve (AAC0-30 min) expressed as a percentage of the pre-exercise value. Changes in both exercise variables were also analysed in percentile subgroups defined by questionnaire answers on habitual physical activity in hours. The mean % fall in FEV1 was significantly higher for treadmill exercise than for the step test (15.0 +/- 7.5 versus 11.7 +/- 5.9); and the AAC0-30 min was larger for treadmill than for the step test (-261.6 +/- 139.9% versus -197.3 +/- 105.0% min). In all subgroups defined by habitual physical activity the mean % fall in FEV1 decreased more after treadmill exercise than after the step test. After step test and treadmill exercise no significant correlation was found between % fall in FEV1 and baseline lung function, or between % fall in FEV1 among groups defined by habitual physical activity. Although the 3-min step test yields a lower % fall in forced expiratory volume in one second (FEV1) and a lower value of the area above the FEV1 curve than treadmill testing, it is a quick, economical, reproducible and portable alternative procedure for identifying exercise-induced asthma in outpatients and epidemiological studies. Baseline lung function and habitual physical activity have no influence on the amount or duration of exercise-induced asthma.  相似文献   
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We sequenced all mitochondrial tRNA genes from a patient with sporadic external ophthalmoplegia (PEO) and 5% COX-negative fibers in muscle biopsy, who had no detectable large mtDNA deletions. Direct sequencing showed a heteroplasmic mutation at nucleotide 7506 in the dihydrouridine stem of the tRNA(Ser(UCN)) gene. RFLP analysis confirmed that 30% of muscle and 20% of urinary epithelium mtDNA harbored the mutation, which was absent in other tissues of the proband as well as in mtDNA of his mother and 100 patients with various encephalomyopathies. Several point mutations on mitochondrial tRNA genes have been reported in PEO patients without large-scale rearrangements of mtDNA but no point mutations have hitherto been found in the gene coding for tRNA(Ser(UCN)).  相似文献   
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To investigate whether a hospital-supervised program of chest physical therapy improves lung function in children with chronic pulmonary diseases, twenty-four children (4 with Kartagener?s syndrome, 12 with common variable immunodeficiency, and 8 with primary ciliary dyskinesia) average age 11.2 +/- 3.2 years, were randomly assigned to a one-month hospital-supervised program of chest physical therapy (13 patients) or to a control group (11 patients) that continued unsupervised chest physical therapy at home. Lung function was assessed before the program, and one and 12 months after. At the one-month assessment, thoracic gas volume was significantly lower in the supervised group than in the controls. At the one-year assessment, forced expiratory volume in one second was significantly higher in the supervised group than in controls. A supervised program of chest physical therapy significantly improved lung function in children with chronic pulmonary diseases.  相似文献   
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