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OBJECTIVE: The aim of this study was to measure leakage of 4 resin-based sealers. STUDY DESIGN: Four groups of premolars (n = 60) were prepared using GT Rotary files and the crown-down technique and filled by the single-cone technique with AH26, AHPlus, EndoREZ, and an experimental MBP as sealer. Leakage was measured using the fluid filtration method after 15, 30, and 60 days and determined as microL/min(-1) x 10 psi. RESULTS: Statistical analysis by ANOVA and Tukey HSD test indicated that root fillings with AH Plus and the MBP showed lower leakage values after 15 days (P < .05). At 30 days, AH26 presented higher leakage values when compared to other sealers (P < .05). At 60 days, MBP and AH Plus presented the lower leakage values, differing significantly from EndoREZ (P < .05). CONCLUSION: It was observed that AH Plus and the experimental MBP showed lower leakage after 60 days than AH 26 and EndoREZ.  相似文献   
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OBJECTIVE: To describe the optimal surgical strategy in heart specimens with transposition of the great arteries (TGA) and left ventricular outflow tract obstruction (LVOTO). METHODS: Thirty-three specimens with LVOTO were selected: TGA with intact ventricular septum (TGA/IVS) (10), TGA/VSD (21), and Taussig-Bing (2). RESULTS: LVOTO in TGA/IVS consisted of combinations of bicuspid pulmonary valve (four), subpulmonary fibrous ridge (four), obstructive muscular conus (two) and bulging muscular septum (four). Arterial switch operation (ASO) with LVOTO resection/valvotomy was feasible in nine hearts. Obstructive anterior papillary muscle prohibited LVOTO relief in one specimen. In TGA/VSD and Taussig-Bing LVOTO consisted of combinations of bicuspid (nine) or unicommissural (one) pulmonary valve, fibrous ridge (three), obstructive muscular conus (five), malaligned outlet septum (six), accessory mitral valve tissue (two), straddling mitral valve (two) and anterior mitral valve rotation (four). VSDs were subpulmonary in 13 (9 perimembranous, 4 muscular), subaortic in 3 (2 perimembranous, 1 anterior muscular), doubly committed in 2, inlet in 3 (2 perimembranous, 1 muscular), non-committed and anterior in 1, and finally 1 VSD extended both into inlet and subpulmonary outlet septum. LVOTO resection and ASO with VSD closure was possible in 10. In six specimens, both a Rastelli and a Nikaidoh operation were feasible. For two hearts, a Nikaidoh procedure was the only option, while Rastelli was considered optimal in another specimen. Mitral valve anomalies prevented LVOTO relief in four, only permitting for Senning/VSD closure (one) or univentricular palliation (three). CONCLUSIONS: LVOTO resection and pulmonary valvotomy frequently permits an ASO. Inlet VSD, impossibility of VSD enlargement, straddling mitral valve, distant aorta and small right ventricle make the Nikaidoh procedure the best option. Mitral anomalies preventing LVOTO relief can make biventricular repair impossible.  相似文献   
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In the present study we developed an enzyme-linked immunosorbent assay (ELISA) to measure immunoglobulin M (IgM) specific for glycoinositolphospholipids (GIPL) derived from tachyzoite membrane (IgM-GIPL ELISA). The sensitivity and specificity of the assay were compared with those of commercially available Toxoplasma-specific IgM serological tests, namely, immunofluorescence assay (IFA) with fixed tachyzoites and capture ELISA employing tachyzoite extracts. Our results show that all patients with acute toxoplasmosis, as determined by clinical data and conventional serological tests, were also positive by the IgM-GIPL ELISA. Interestingly, many patients that were classified as indeterminate, who had IgG with high avidity but positive results in the IgM-specific IFA and capture ELISA, were negative by the IgM-GIPL ELISA. Finally, we tested the sera from patients with rheumatoid arthritis and various parasitic infections and found no evidence of false positives in the IgM-GIPL ELISA.  相似文献   
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The complete genetic information for the neuraminidase (NA) gene of influenza virus A/Bangkok/1/79 has been cloned by in vitro synthesis of dsDNA, insertion into pBR322 plasmid, and transformation of Escherichia coli. The nucleotide sequence of the NA gene has been determined by the Maxam and Gilbert method. It is 1466 nucleotides long and contains a single open reading frame with a coding capacity for 469 amino acids. When compared to the NA genes of the N2 strains A/Victoria/3/75, A/Udorn/72, A/NT/60/68, and A/RI/5-/57, 90% of the nucleotide positions and 87% of the amino acid positions remained invariant. Forty-two nucleotide changes and 14 amino acid changes accumulated in the period 1975-1979, but the general structure of the protein appeared to remain constant.  相似文献   
6.
Data from the Hospital Information System (SIH-SUS) were linked to data from the AIDS Case Reporting System (Sinan) to assess the level of under-reporting of AIDS cases in the city of Rio de Janeiro. A high level of unreported cases(42.7%) was observed for patients treated in hospitals under Brazil's Unified Health System in the city of Rio. Bivariate analysis showed an association between reporting to the Sinan and age, principal diagnosis, and type of hospital.  相似文献   
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Long-term exposure to low levels of organophosphate pesticides (OP) may produce neuropsychiatric symptoms. We performed clinical, neuropsychiatric, and laboratory evaluations of 37 workers involved in family agriculture of tobacco from southern Brazil who had been exposed to OP for 3 months, and in 25 of these workers, after 3 months without exposure to OP. Plasma acetylcholinesterase activity levels of all subjects were within the normal range (3.2 to 9.0 U/l) and were not different between on- and off-exposure periods (4.7 +/- 0.9 and 4.5 +/- 1.1 U/l, respectively). Clinically significant extrapyramidal symptoms were present in 12 of 25 subjects, which is unexpected in such a population. There was a significant reduction of extrapyramidal symptoms after 3 months without exposure to OP, but 10 subjects still had significant parkinsonism. Mini-mental and word span scores were within the expected range for this population and were not influenced by exposure to OP. Eighteen of the 37 subjects (48%) had current psychiatric diagnoses in the first interview (13 with generalized anxiety disorder and 8 with major depression). Among the 25 subjects who completed both evaluations, the total number of current psychiatric diagnoses, after 3 months without using OP, dropped from 24 to 13 and the number of affected individuals with any psychiatric diagnosis dropped from 11 to 7. In conclusion, this study reinforces the need for parameters other than acetylcholinesterase activity to monitor for chronic consequences of chronic low-dose OP exposure, and it suggests that subjects have not only transient motor and psychiatric consequences while exposed, but may also develop enduring extrapyramidal symptoms.  相似文献   
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Recurrent gastroesophageal reflux following fundoplication is a challenging problem, because it is usually refractory to medical treatment and a second, technically difficult, antireflux operation is required. Different factors that may contribute to surgery failure have been identified in children. We present 8 cases who underwent redofundoplication after failed procedures, from a total number of 96 patients operated on due to gastroesophageal reflux. Four patient's had their initial fundoplication performed at our institution. Six patients were neurologically impaired, six had chronic pulmonary disease, and two had esophageal atresia. The main presenting symptoms were recurrent vomiting (n = 8) and aspiration (n = 4). Gastroesophageal reflux was confirmed by barium swallow and endoscopy. Operative findings showed wrap breakdown in two cases, warp breakdown associated with hiatal hernia in five, wrap breakdown associated with paraesophageal hernia in two cases, and paraesophageal hernia with normal wrap in one. A second Nissen procedure were performed in five cases, whereas a Collis-Nissen gastroplasty was realized in three with a short esophagus. Six patients had a successful outcome remaining symptom free, one has severe disphagia, and one has recurrent vomiting. In our experience, patients with recurrent gastroesophageal reflux disease should undergo an antireflux procedure tailored to specific anatomic or functional abnormalities.  相似文献   
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