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51.
International Journal of Paediatric Dentistry 2013; 23: 145–152 Background. Alternatives to vital pulpotomy treatment in primary teeth are being sought because of the high formaldehyde content of traditional formocresol (FC) pulpotomy medicaments. Aim. The aim was to compare the clinical and radiographic success of vital pulpotomy treatment in primary molars using 3% sodium hypochlorite (NaOCl) versus a 1 : 5 dilution of Buckley’s FC. Design. Pulpotomies were performed in primary molars of healthy children between 3 and 10 years old. Sixty‐five primary teeth were randomized into two groups that were evaluated for treatment outcomes. Following treatment, the pulp chamber was filled with zinc oxide eugenol (ZnOE) and restored with a stainless steel crown cemented with glass ionomer cement. Clinical and radiographic outcomes were recorded at 6 and 12 months. Results. The control (FC) and experimental (NaOCl) groups demonstrated 100% clinical success at 6 and 12 months. The NaOCl group had 86% (19/22) radiographic success at 6 months and 80% (12/15) at 12 months. The FC group had 84% (21/25) radiographic success at 6 months and 90% (9/10) at 12 months. No significant differences were found in the radiographic outcomes between the two groups at 6 and 12 months (Fisher’s exact test; P = 0.574 and P = 0.468, respectively). Conclusion. NaOCl demonstrated clinical and radiographic success comparable to FC.  相似文献   
52.
The dehydrophenylalanine4-enkephalin having the E-configuration (ΔEPhe; phenyl and C = O, cis) was prepared by photoisomerization of the Z-isomer with 3100 Å light, followed by reversed-phase HPLC separation of the resulting mixture of the Z- and E-isomers. In the radioligand receptor binding assays, the E-isomer of [D-Ala2, ΔPhe4, Leu5]enkephalin exhibited an extremely diminished affinity as compared with the Z-isomer, namely 150–260-fold loss of affinity for the delta and mu opiate receptors. The results indicate that the interrelationship of the Tyr1 and Phe4 residues in the enkephalin molecule seems to be of great importance in receptor recognition.  相似文献   
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54.
Aim  We aimed to investigate the contribution of disease stage and weight for age to the variability in psychomotor outcome observed among children with human immunodeficiency virus (HIV) infection.
Method  This cross-sectional study involved 48 Kenyan children (20 females, 28 males) aged 6 to 35 months (mean 19.9mo SD 8.9) exposed prenatally to HIV. Two subgroups of HIV-exposed children were seen: those who were HIV-infected and those who were uninfected. The reference population was composed of 319 children (159 females, 160 males) aged 6–35 months, (mean age = 19 months, SD=8.43) randomly selected from the community. Disease stage varied from stage 1 to stage 3, reflecting progression from primary HIV infection to advanced HIV infection and acquired immune deficiency syndrome. A locally developed and validated measure, the Kilifi Developmental Inventory, was used to assess psychomotor development.
Result  Using age-corrected psychomotor scores, a significant main effect of HIV status was observed ( F (2,38.01)=7.89, p <0.001). Children in the HIV-infected group had lower mean psychomotor scores than the HIV-exposed children and the reference group. In the HIV-infected group, disease stage was a negative predictor and weight for age a positive predictor of psychomotor outcome.
Interpretation  Weight for age and disease stage provide viable, easily measurable benchmarks to specify when frequent developmental monitoring and psychomotor rehabilitation are required. Nutritional intervention and other measures aimed at slowing disease progression may delay the onset and severity of psychomotor impairment in the paediatric HIV population in Africa.  相似文献   
55.
Endothelial cell dysfunction in homocystinuria   总被引:10,自引:0,他引:10  
Abstract. This report describes the isolation and culture of venous endothelial cells from the umbilical cord of an obligate heterozygote for homocystinuria. The effect of different sulphur-containing amino acids on the viability and function of these cells was studied and compared with cultured normal endothelial cells. When endothelial cells were cultured in the presence of methionine (10 mmol/l) or homocystine (10 mmol/l), differences occurred between the viability and function of the heterozygote and normal cells in terms of 51Cr release and ability to prevent platelet adherence. The Cr release corrected for spontaneous release increases for the heterozygote cells after incubation for 21 h in the presence of methionine to 81.3% (control cells, range: 0–23.3%, n = 5) and in the presence of homocystine to 141% (control cells, range: 13.5–55.2%, n = 5). The total number of platelets that adhere to confluent monolayers increases for heterozygote cells cultured in the presence of methionine to 0.98 ± 107 platelets cm-2 (normal cells, range: 0.56–0.72 ± 107 platelets cm-2) and in the presence of homocystine to 1.41 ± 107 platelets cm-2 (normal cells, range: 0.94–1±06 ± 107 platelets cm-2). Both normal and control cells were sensitive to homocysteine. This study indicates for the first time what vascular endothelial cells, derived from an obligate heterozygote, are (partly) deficient in cysthathionine synthase and are more susceptible to methionine- and homocystine-mediated injury than normal endothelial cells. Consequently, in homocystinuria, due to dysfunction of the endothelial cells, toxic sulphur-containing amino acids may accumulate in these cells, causing injury of these cells.  相似文献   
56.
We sought to determine the international experience with the quadripolar diaphragm pacer system and to test two hypotheses: the incidence of pacer complications would be (1) increased among pediatric as compared to adult patients; and (2) highest among active pediatric patients with idiopathic congenital central hypoventilation syndrome (CCHS). Data were collected via a questionnaire coupled with the Atrotech Registry data for a total of 64 patients (35 children and 29 adults) from 14 countries. Thoracic implantation of electrodes and bilateral pacer use each occurred in 94% of all subjects. Tetraplegic (vs pediatric CCHS) patients were more typically paced 24 hours/day (P = 0.001). Pacing duration averaged 2.0 ± 1.0 years among children and 2.2 ± 1.1 years among adults. Infections occurred among 2.9% of surgical procedures, all in pediatric CCHS patients (vs pediatric tetraplegic patients, P = 0.01). The incidence of mechanical trauma was 3.8%, without significant differences among patient groups. The incidence of presumed electrode and receiver failure were 3.1% and 5.9%, respectively, with internal component failure greater among pediatric CCHS than pediatric tetraplegic patients (P < 0.01). Intermittent or absent function of 0–4 electrode combinations occurred among 19% of all patients, with increased frequency among pediatric CCHS than pediatric tetraplegic patients (P < 0.03). Complication- free successful pacing occurred in 60% of pediatric and 52% of adult patients. In all, 94 % of the pediatric and 86% of the adult patients paced successfully after the necessary intervention. Although pacer complications were not increased among pediatric as compared to adult patients, the incidence of complications was highest among the active pediatric patients with CCHS. Longitudinal study of these patients will provide invaluable information for modification and improvement of the quadripolar system.  相似文献   
57.
Intravascular Lead Extraction Using Locking Stylets and Sheaths   总被引:2,自引:0,他引:2  
BYRD, C.L., ET AL.: Intravascular Lead Extraction Using Locking Stylets and Sheaths. Chronic lead extraction using intravascular countertraction techniques was studied in patients with over 65 different lead models including passive and active fixation devices. Indications for removal of 115 leads implanted 5 days to 264 months (mean 58 months) in 62 patients (mean 65 years) included septicemia, subcutaneous tissue infection, preerosion, free-floating lead, lead trapped in valve, too many leads, pain, and vein thrombosis. The superior vena cava (SVC) approach was attempted in 101 leads and was successful in 82 attempts (71% of total leads). The inferior vena cava (IVC) approach via the femoral vein was required to extract 14 (12%) leads inaccessible to the SVC approach and the 19 leads that failed the SVC approach (29% of total leads). The SVC procedure includes a sized stylet locked at the tip and telescoping sheaths advanced over the lead to the heart. An IVC procedure includes placement of a 16 F sheath workstation via a femoral vein into the right atrium. A deflection catheter and Dotter snare in an 11 F sheath were advanced through the workstation into the right atrium. The lead was maneuvered into position, snared, and pulled into the workstation. For both the SVC and IVC approaches, the leads were removed by applying traction on the lead and countertraction with the sheaths. In experienced hands, these techniques have proven safe and effective for removing chronic transvenous leads.  相似文献   
58.
Amiodarone Reduces Transmural Dispersion. Introduction: Amiodarone is a potent antiarrhythmic agent used in the management of both atrial and ventricular arrhythmias. In addition to its β-blocking properties, amiodarone is known lo block the sodium, potassium, and calcium channels in the heart. Its complex electropharmacology notwithstanding, the reasons for the high efficacy of the drug remain unclear. Also not well understood is the basis for the low incidence of proarrhythmia seen with amiodarone relative to other agents with Class III actions. The present study was designed to examine the effects of chronic amiodarone in epicardial, endocardial, and M cells of the canine left ventricle. Methods and Results: We used standard microelectrode techniques to record transmembrane activity from endocardial, epicardial, mid-myocardial, and transmural strips isolated from the canine left ventricle. Tissues were obtained from mongrel dogs receiving amiodarone orally (30 to 40 mg/kg per day) for 30 to 45 days or from untreated controls. Chronic amiodarone produced a greater prolongation of action potential duration in epicardium and endwardium, but less of an increase, or even a decrease at slow rates, in the M region, thereby reducing transmural dispersion of repolarization. In addition, chronic amiodarone therapy suppressed the ability of the Ikr, blocker, d-sotalol, to induce a marked dispersion of repolarization or early afterdepolarization activity. Conclusion: Our data demonstrate for the first time a direct effect of chronic amiodarone treatment to differentially alter the cellular electrophysiology of ventricular myocardium so as to produce an important decrease in transmural dispersion of repolarization, especially under conditions in which dispersion is exaggerated. These results may contribute to our understanding of the effectiveness of amiodarone in the treatment of life-threatening arrhythmias as well as to our understanding of the low incidence of proarrhythmia attending therapy with chronic amiodarone in comparison with other Class III agents.  相似文献   
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60.
Catheter ablation of AV conduction with radiofrequency energy can be challenging in the presence of structural abnormalities of the AV junction, either congenitally or after reconstructive surgery. We used transcoronary ethanol to ablate the AV node in a patient with classic tricuspid atresia and refractory intraatrial reentry tachycardia. This approach provides an alternative means of creating complete heart block with catheter-based techniques, when radiofrequency catheter ablation is technically impossible or ineffective.  相似文献   
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