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DNJ Ricketts EAM Kidd N. Innes J. Clarkson DR GRAHAM J MOUNT AM 《Australian dental journal》2007,52(3):252-253
Background : The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique). Objectives : To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete. Search strategy : The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked. Selection criteria : Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth. Data collection and analysis : Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model. Main results : Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration. Authors' conclusions : The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably. Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. Plain language summary : A systematic review of the literature revealed four studies comparing complete and minimal (ultraconservative) caries removal. It was found that partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure. Therefore, partial caries removal is preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. 相似文献
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B SAKA M AKTAN U SAMI D ONER O SANEM G DINOL 《International journal of laboratory hematology》2006,28(1):30-35
Soluble CD23 (sCD23) was proposed as a marker of disease activity and as an important prognostic parameter in B‐cell chronic lymphocytic leukemia (B‐CLL). In this study, prognostic significance of sCD23 in B‐CLL was examined according to its temporal relationship with the known clinical parameters of the disease, CD38 and ZAP‐70. Serum sCD23 levels of 36 B‐CLL patients, followed up in our clinic between 1999 and 2005, and 15 healthy subjects were measured with enzyme‐linked immunosorbent assay. The mean serum sCD23 level of the B‐CLL patients (210.72 ± 193.67 and 6–600 U/ml) was significantly higher than the control group (18.20 ± 14.30 and 6–50 U/ml). Seventy‐eight percent of the B‐CLL patients with lymphocyte doubling time (LDT) <12 months and 24% of patients with LDT >12 months had high sCD23 levels (P = 0.008). Meanwhile, 81% of the patients with diffuse bone marrow infiltration and 33% of patients with nondiffuse infiltration had high levels of serum sCD23 (P = 0.029). A significant difference was found between B‐CLL patients with Binet stages A and C (P = 0.009). Peripheral blood flow cytometry of the patients revealed a significant CD38 expression in patients with high serum sCD23 levels (P = 0.002). Similarly, an increased bone marrow zeta‐chain associated protein kinase‐70 (ZAP‐70) expression was seen in patients with high serum sCD23 levels (P = 0.009, correlation co‐efficient was 0.714). Cumulative and the progression free survivals of the patients with low serum sCD23 levels were 60.1 ± 5.7 months [95% confidence interval (CI); 49.0–71.2] and 51.1 ± 6.6 months (95% CI; 38.0–64.1), respectively. However, they were 43.8 ± 6.5 months (95% CI; 31.0–56.6) and 26.5 ± 6.4 months (95% CI; 14.0–39.1) in patients with high levels. Serum sCD23 is increased in B‐CLL patients and can be used in the clinical follow‐up of the disease in prediction of the tumor mass and prognosis. 相似文献
4.
Radiofrequency Catheter Ablation of the Left and Right Ventricles: Anatomic and Electrophysiologic Observations 总被引:3,自引:0,他引:3
SHOEI K. STEPHEN HUANG ANNA R. GRAHAM KEITH WHARTON 《Pacing and clinical electrophysiology : PACE》1988,11(4):449-459
Certain untoward effects associated with the use of direct-current electrical catheter ablation of the ventricular endomyocardium have been noted. We assessed the efficacy and safety of closed-chest catheter ablation of the left and right ventricles using radiofrequency (RF) energy (750 kHz) in six dogs. Mean RF energies between 93 and 123 joules (J) were randomly delivered to three left ventricular (LV) sites via two distal adjacent electrodes (bipolar configuration) using 6-7F USCI tripolar or quadripolar catheters with an interelectrode distance of 5-10 mm. Another 90-143 J were given to two right ventricular (RV) sites in single or multiple divided applications between a distal electrode and an external patch electrode (unipolar configuration). Ventricular arrhythmias were not observed during application of RF energy. Programmed ventricular stimulation before and after the procedure did not induce ventricular tachycardia (VT) or fibrillation except in one dog who had inducible VT prior to ablation. There were no significant changes in LV and RV effective refractory periods after the procedures. Occasional premature ventricular beats and rare episodes of non-sustained VT (3-12 beats) were observed in ambulatory electrocardiographic recordings (13-24 hrs) done immediately after ablation. Dogs were sacrificed after 4-5 days. Pathology showed well-demarcated round or ovoid lesions of varying sizes. Mural thrombus was found in one dog. Microscopic findings consisted of circumscribed areas of coagulation necrosis with a peripheral zone of cellular infiltration. Transmural necrosis without perforation was occasionally seen in the thin RV wall when higher energies were delivered. In conclusion, discrete areas of desiccation injury in the ventricles can be achieved by transcatheter bipolar or unipolar ablation using RF energy. The complications associated with this method appear to be minimal. Further experiments are needed to evaluate its potential for catheter ablation of ventricular tachycardia. 相似文献
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Summary When dipotassium EDTA anticoagulated platelet rich plasma was incubated against a range of hypotonic saline concentrations, platelet volume was seen to change in a particular and rcproducible fashion. When platelets taken from patients suffering a thromboembolic episode were tested in the same manner, a different pattern of response was observed the platelets being far less tolerant to osmotic stress. Similar changes occurred in platelets from ante-natal subjects. Platelets from both groups regained their tolerance to hypotonicity following either the thromboembolic incident or parturition respectively. 相似文献
8.
JILL EDITH KISLER ROGER GRAHAM WHITTAKER ROBERT MCFARLAND 《Developmental medicine and child neurology》2010,52(5):422-433
Mitochondrial diseases are a common cause of inherited neurological disorders in children. Although dysfunction of the central nervous system is prominent, multisystem involvement also occurs. Diagnosis relies on characteristic clinical features, an understanding of mitochondrial genetics, and a logical, informed approach to investigations. There is a significant body of recent literature on advances in mitochondrial genetics and the investigation of mitochondrial diseases. However, to our knowledge there remains a paucity of published information on the management of these disorders. Management of the complex constellation of neurological and multisystem clinical features is challenging, and is reliant on a multidisciplinary approach. The care of the child and family is dependent on clear communication between health professionals from primary, secondary, and tertiary care as well as specialist input from quaternary services. The aim of this review is to provide paediatric neurologists, paediatricians, and allied health professionals with a structured approach to the diagnosis and management of children with suspected or confirmed mitochondrial disease. 相似文献
9.
SANTABHANU CHAKRABARTI M.D. GERGELY SZANTHO M.D. MARK S. TURNER Ph .D. M.R.C.P. GRAHAM STUART F.R.C.P. F.R.C.P.C.H. ROBIN P. MARTIN F.R.C.P. F.R.C.P.C.H. 《Pacing and clinical electrophysiology : PACE》2009,32(9):1123-1129
Background: Endocardial pacemaker lead placement can be challenging after Mustard and Senning operations for transposition of the great arteries (D-TGA), if there is atresia of the systemic venous pathways and because the coronary sinus cannot be used for cardiac resynchronization therapy. Radiofrequency (RF)-assisted perforation techniques have been used in congenital heart disease but have not been reported for use in pacemaker implantation.
Methods and Results: We describe RF perforation of an atretic superior systemic venous pathway and systemic venous baffles in three patients after Senning and Mustard operations to implant endocardial pacing systems to achieve conventional or biventricular pacing.
Conclusions: RF-energy-assisted perforation is feasible and effective tool to facilitate endocardial lead placement during dual-chamber and biventricular pacemaker implantation in patients with Mustard or Senning operations for D-TGA. 相似文献
Methods and Results: We describe RF perforation of an atretic superior systemic venous pathway and systemic venous baffles in three patients after Senning and Mustard operations to implant endocardial pacing systems to achieve conventional or biventricular pacing.
Conclusions: RF-energy-assisted perforation is feasible and effective tool to facilitate endocardial lead placement during dual-chamber and biventricular pacemaker implantation in patients with Mustard or Senning operations for D-TGA. 相似文献
10.
TANYA SHYAMI PEIRIS GRAHAM J. ROBERTS & NEETA PRABHU 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2009,19(5):367-376
Background. The physiological age of a person is determined by the degree of maturation of the different tissue systems. Children of the same chronological age (CA) can demonstrate different degrees of maturation. Dental age (DA) is based on the maturation of teeth. Tooth formation is a continuous process, where the developmental stages of the tooth can be sequenced and defined depending on the degree of mineralization. These stages can be visualized on a dental panoramic tomograph (DPT).
Aim. The aim of this study was to use a new method of Dental Age Assessment (DAA) to compare a United Kingdom (UK) and an Australian (AUS) population.
Design. The DPTs used are from the archives of the Westmead Centre for Oral Health (Westmead, Australia) and the King's College London Dental Institute. From the preliminary sample of 89 DPTs from each population, 77 were suitable for use as matched pairs. The radiographic technique used was developed by Demirjian and describes eight stages of tooth development. This was used in combination with numerical data derived from a meta-analysis of a single UK subject.
Results. A significant difference was shown between the CA and DA of the AUS patients. The AUS patients were also shown to have a significant 0.82 years delay in their DA compared to the UK patients. The findings indicate a difference in AUS compared to UK patients. These results indicate the need to develop a reference data set for the AUS population for DAA.
Conclusions. This research is of significance in a number of clinical disciplines and can also be used to assist in age determination of subjects of unknown birth date to assist in forensic dentistry or social deliberations. 相似文献
Aim. The aim of this study was to use a new method of Dental Age Assessment (DAA) to compare a United Kingdom (UK) and an Australian (AUS) population.
Design. The DPTs used are from the archives of the Westmead Centre for Oral Health (Westmead, Australia) and the King's College London Dental Institute. From the preliminary sample of 89 DPTs from each population, 77 were suitable for use as matched pairs. The radiographic technique used was developed by Demirjian and describes eight stages of tooth development. This was used in combination with numerical data derived from a meta-analysis of a single UK subject.
Results. A significant difference was shown between the CA and DA of the AUS patients. The AUS patients were also shown to have a significant 0.82 years delay in their DA compared to the UK patients. The findings indicate a difference in AUS compared to UK patients. These results indicate the need to develop a reference data set for the AUS population for DAA.
Conclusions. This research is of significance in a number of clinical disciplines and can also be used to assist in age determination of subjects of unknown birth date to assist in forensic dentistry or social deliberations. 相似文献