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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   
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53.
This study was performed to evaluate the effects of radiofrequency catheter ablation in the coronary sinus as a potential means of eliminating conduction over left-sided accessory pathways in humans. Radiofrequency current at a frequency of 500 kHz was delivered by electrode catheter to two sites in the coronary sinus of each often dogs. Left coronary arteriography with venous phase visualization of the coronary sinus was performed before, immediately after, and 2 weeks following ablation. Unipolar electrograms from the ablating electrode were recorded before and immediately after ablation. Coronary arteriography revealed no evidence of damage to the adjacent left circumflex coronary artery or its branches as a result of ablation. Contrast visualization of the coronary sinus showed persistent contrast staining following ablation at two of the ablated sites. Angiographically apparent stenosis of the coronary sinus was seen both acutely and chronically in two cases. Unipolar electrogram recordings from the ablating electrode showed an increase in atrial repolarization voltage (atrial current of injury) of 1.53 ± 1.03 mV (P = 0.00004), and an increase in ventricular repolarization voltage of 0.73 ± 0.84 mV (P = 0.005). There was a 23% decrease in amplitude of atrial electrograms (P = 0.006) and a 7% decrease in amplitude of ventricular electrograms (P = 0.02) recorded from the ablating electrode following ablation. Lesions could be identified grossly and microscopically at 16 of the 20 ablated sites. Perforation of the coronary sinus did not occur. Microscopical observation showed normal healing with granulation tissue and fat necrosis extending outward from the coronary sinus involving the atrial epicardium in 13 lesions, the ventricular epicardium in 5 lesions, and the adventitia of the left circumflex coronary artery in 5 lesions. No medial or intimal involvement of the coronary artery was seen. The coronary sinus itself showed luminal organized thrombus in 4 lesions, with near occlusion of the lumen in 1 case. Radiofrequency ablation in the coronary sinus thus results in lesions of a size and extent that would be expected to successfully ablate some left-sided accessory pathways if delivered in humans. Monitoring of the unipolar electrogram provides insight into the extent of injury during ablation. In some cases, thrombosis of the coronary sinus occurs, the long-term effects of which are not known.  相似文献   
54.
Introduction and Aims. To describe the characteristics of non‐fatal medication‐related ambulance attendances in Melbourne. Design and Methods. A retrospective analysis of 16 705 patient care records completed by ambulance paramedics in Melbourne where medications had a causal role in the attendance. Results. A single medication only was implicated in 11 765 cases (70% of the total). Of these, 85% involved one of six types of medication: benzodiazepines (52%), paracetamol (15%), selective serotonin re‐uptake inhibitors (6.5%), combination paracetamol and opioids (4%), phenothiazines (3.4%) and tricyclic antidepressants (TCA) (3.7%). Cases involving benzodiazepines were significantly (P < 0.001) older (Average = 37 years) than those involving paracetamol (Average = 30 years). Thirty‐four per cent of cases involved concurrent alcohol use, and this varied according to drug type (paracetamol 26%, benzodiazepines 40%, selective serotonin re‐uptake inhibitors 35%, paracetamol and opioids 35%). An abnormal Glasgow Coma Scale score was found in 19% of cases, again varying according to drug type (paracetamol 10%, TCA 39%, benzodiazepines 21%, paracetamol and opioids 17%, phenothiazines 15%). Ten per cent of cases were not transported to hospital ranging from 3% for TCA to 13% for benzodiazepines. Discussion and Conclusions. The majority of non‐fatal medication events attended by ambulance paramedics involve one of six substances. Benzodiazepines were most commonly implicated and, as management may require only simple supportive treatment, significant numbers are not transported to hospital. The unique clinical population is identified in this study and the ongoing medical and psychiatric treatment of these patients not transported to hospital in the study period needs to be considered. [Hutton J, Dent A, Buykx P, Burgess S, Flander L, Dietze P. The characteristics of acute non‐fatal medication‐related events attended by ambulance services in the Melbourne Metropolitan Area 1998–2002. Drug Alcohol Rev 2009]  相似文献   
55.
Article Title:  The Work-Up and Management of Patients with Apparent or Subclinical Cardiac Sarcoidosis: With Emphasis on the Associated Heart Rhythm Abnormalities.  相似文献   
56.
Boc-l -Lysine derivatives and lysine-containing peptides bearing the electron donor 10H-phenothiazine (PTZ) or the redox chromophore tris(2,2′-bipyridine)ruthenium(II) dication ([Rub3,]2H, where b is 2,2-bipyridine) have been synthesized and characterized. SeO2 oxidation (53% yield) of 4,4′-dimethyl-2,2′-bipyridine, Ag2:O oxidation (85% yield) of the monoaldehyde, complexation (96% yield) of 4′-methyl-2,2′-bipyridine-4-carboxylic acid (m-OH) with Rub2Cl2:. activation (81% yield) of the acid [Rub2m-OH]2+ (PF6?)2, and condensation (83% yield) of the succinimido ester [Rub2m-OSu]2+ (PF6?)2 with Boc-Lys furnished the protected redox-chromophore module [Boc-Lys(Rub2m)-OH]2+(PF6?)2 in 29% overall yield over five steps. The first two steps constitute the first practical synthesis of the monocarboxylic acid m-OH (45% overall yield). Also prepared were m-OSu, Boc-Lys(m)-OH, Boc-Lys(m)-OCH3, and [Rub2m-NHCH3]2+ (PF6?)2:. Activation (91% yield) of 3-(10H-phenothiazine-10)propanoic acid (PTZpn-OH) and condensation (92% yield) of the succinimido ester PTZpn-OSu with Boc-Lys furnished the protected electron-donor module Boc-Lys(PTZpn)-OH (84% overall yield). The latter was used in solid-phase syntheses of two redox tripeptides. CH3CO-Ala-Lys(PTZpn)-Ala-OH and [Rub2m-Ala-Lys(PTZpn)-Ala-OH]2 (PF6?)2. The electrochemical properties of these redox amino acids and peptides were similar to those of PTZpn-OH, [Rub2 m-OH]2+(PF6)2. or [Rub2 m-NHCH3]2+ (PF6?)2. Lys(PTZpn). [Lys(Rub2m)]2+ (PF6)2:. and other redox modules may be useful for engineering light-harvesting proteins, photovoltaic cells, and other molecular electronic devices.  相似文献   
57.
This paper reports the construction of gross motor development curves for children and youth with cerebral palsy (CP) in order to assess whether function is lost during adolescence. We followed children previously enrolled in a prospective longitudinal cohort study for an additional 4 years, as they entered adolescence and young adulthood. The resulting longitudinal dataset comprised 3455 observations of 657 children with CP (369 males, 288 females), assessed up to 10 times, at ages ranging from 16 months to 21 years. Motor function was assessed using the 66-item Gross Motor Function Measure (GMFM-66). Participants were classified using the Gross Motor Function Classification System (GMFCS). We assessed the loss of function in adolescence by contrasting a model of function that assumes no loss with a model that allows for a peak and subsequent decline. We found no evidence of functional decline, on average, for children in GMFCS Levels I and II. However, in Levels III, IV, and V, average GMFM-66 was estimated to peak at ages 7 years 11 months, 6 years 11 months, and 6 years 11 months respectively, before declining by 4.7, 7.8, and 6.4 GMFM-66 points, in Levels III, IV, and V respectively, as these adolescents became young adults. We show that these declines are clinically significant.  相似文献   
58.
The Costs of Recurrent Syncope of Unknown Origin in Elderly Patients   总被引:6,自引:0,他引:6  
Although syncope has been shown to reduce quality-of-life, its impact on resource costs has not been documented. The objective of this study was to quantify the annual medical costs of caring for elderly patients with syncope, especially recurrent syncope of unknown origin. Administrative data from the Health Care Financing Administration were obtained on 7,959 Medicare patients who had at least one inpatient admission with a diagnosis of syncope in 1993. The costs of any inpatient admissions, outpatient procedures, or physician visits with an ICD-CM-9 diagnosis for syncope were summed for a 365-day period from the date of the initial hospitalization for syncope. Patients who had at least two hospitalizations with admission and discharge diagnosis of syncope were deemed to have recurrent syncope of uncertain origin. To better estimate syncope costs for those whose syncope costs could have been attributed to other diagnoses, a regression analysis was performed including variables representing the most frequent secondary diagnoses. The average annual costs of those who were admitted with syncope but who were discharged with another diagnosis was $4,942 in 1993. The average annual cost of patients with recurrent syncope deemed to be of unknown origin was $5,165. For those patients with secondary diagnoses of atherosclerosis, urinary tract infections, or hypokalemia, the annual costs of syncope averaged $6,820, $7,013, or $7,949, respectively.  相似文献   
59.
Inappropriate therapies delivered by implantable cardioverter defibrillators (ICDs) for supraventricular arrhythmias remain a common problem, particularly in the event of rapidly conducted atrial fibrillation or marked sinus tachycardia. The ability to differentiate between ventricular tachycardia and supraventricular arrhythmias is the major goal of discrimination algorithms. Therefore, we developed a new algorithm, SimDis, utilizing morphological features of the shocking electrograms. This algorithm was developed from electrogram data obtained from 36 patients undergoing ICD implantation. An independent test set was evaluated in 25 patients. Recordings were made in sinus rhythm, sinus tachycardia, and following the induction of ventricular tachycardia and atrial fibrillation. The arrhythmia complex is defined as wide if the duration is at least 30% greater than the template in sinus rhythm. For narrow complexes, four maximum and minimum values were measured to form a 4-element feature vector, which was compared with a representative feature vector during normal sinus rhythm. For each rhythm, any wide complex was classified as ventricular tachycardia. For narrow complexes, the second step of the algorithm compared the electrogram with the template, computing similarity and dissimilarity values. These values were then mapped to determine if they fell within a previously established discrimination boundary. On the independent test set, the SimDis algorithm correctly classified 100% of ventricular tachycardias (27/27), 98% of sinus tachycardias (54/55), and 100% of episodes of atrial fibrillation (37/37). We conclude that the SimDis algorithm yields high sensitivity (100%) and specificity (99%) for arrhythmia discrimination, using the computational capabilities of an ICD system.  相似文献   
60.
Measurements were made, using an acoustic transmission method, of the setting times of three visible-light curing sealants (two filled, one unfilled). Five commercially available visible-light polymerizing sources were tested with each material. Only three of the light sources gave setting times not significantly different from the manufacturers' recommended times for all three materials tested. The variation in microhardness with depth of sealant was measured to study the depth of polymerization of the sealants, all of which were adequate. The filled sealants had microhardness values greater than the unfilled sealant, at all depths studied.  相似文献   
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