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71.
One hundred and ninety-eight consecutive gastrectomy specimens (78 gastric carcinomas, 120 benign lesions) were reviewed and examined to study the relation between intestinal metaplasia (IM) and gastric carcinomas (GC). IM was classified as complete (type I) and incomplete (types II and III) depending on the types of mucin secreted. Only type III IM was found to be significantly associated with GC ( P = 0.0005) when GC was treated as a group in contrast to non-neoplastic lesions. On subdivsion into different types of GC, such association was only found in the intestinal type but not the diffuse type. The significance of the association between type III IM and the intestinal type GC is discussed. In addition, dysplasia was significantly associated with GC and not with benign lesions ( P < 0.005).  相似文献   
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Azimilide and Atrial Flutter. Introduction: The effects of a Class III agent, azimilide di-hydrochloride, on atrial flutter circuits were studied in a functional model of single loop reentrant atrial flutter using dogs, 3 to 5 days after production of sterile pericarditis. Methods and Results: A computerized mapping system was used to construct activation maps from 138 to 222 epicardial sites in the right atrium. Doses of 3, 10, and 30 mg/kg IV azimilide dihydrochloride were analyzed in 8 dogs in which sustained atrial flutter lasting more than 30 minutes was induced by burst pacing. Atrial flutter was always due to a single loop circus movement reentry in the lower right atrium. At 3 mg/kg, azimilide dihydrochloride terminated atrial flutter in 2 dogs; however, atrial flutter was reinduced. At 10 mg/kg, atrial flutter was terminated in all 8 dogs but was reinduced in 4 dogs with slower rate. At 30 mg/kg, atrial flutter was terminated in the remaining 4 dogs and could not be reinduced. Atrial flutter cycle length always increased prior to termination. Isochronal activation maps showed that the increase in cycle length was due to additional conduction delays in the slow zone of the reentrant circuit. The site of termination was always located within the slow conduction zone situated in the lower right atrium between the line of functional conduction block and the AV ring. effective refractory periods (ERPs) were measured at selected sites in the slow zone and normal zone at twice diastolic threshold for the 10 mg/kg dose. Azimilide preferentially prolonged ERP in the slow zone (42.4 ± 20.l msec, mean ± SD) compared with (he normal zone (23.3 ± 15.4 msec, P < 0.0001). The increase in cycle length corresponded with the increase in ERP in the slow zone. Conclusions: In a functional model of circus movement atrial flutter, azimilide dihydrochloride terminates and prevents reinduction of atrial flutter by a preferential increase in refractoriness leading to further conduction delay and conduction block in the slow zone of the functional reentrant circuit.  相似文献   
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Objectives: This study aims to analyze mechanisms for facilitating the uptake of new medical devices in the German system of hospital reimbursement, focusing on the example of coronary stents, including (1) trends in their coding, (2) associated diagnosis‐related group (DRG) payments, (3) their integration in the German DRG (G‐DRG) system, and (4) their diffusion within the inpatient sector. Methods: Published and gray literature provide the basis for analyzing the system of hospital reimbursement. Data on coronary stents were obtained from various regulatory and government bodies and examined in a longitudinal fashion. Results: Although German Procedure Classification (Operationen‐ und Prozedurenschlüssel; OPS) codes were created for a range of stent technologies between 2004 and 2009, the regular system of G‐DRG reimbursement does not distinguish between different stents by means of unique DRGs. Instead, supplementary payments or extrabudgetary payments are used to ensure that newer technologies are reimbursed adequately. The limitations of extrabudgetary payments restrict the use of some devices to a small proportion of patients. Data on the diffusion of different stents show that factors other than the reimbursement regime likely also play a role in the frequency with which certain technologies are used. Bare metal stents currently account for most stent implantation procedures in Germany, followed by drug‐eluting stents. Conclusion: The current system of G‐DRG reimbursement and of extrabudgetary payments ensures that even the most recently developed technologies can be used in the German inpatient sector. Nevertheless, certain technologies may not be reaching the broad patient population. (J Interven Cardiol 2010;23:546–553)  相似文献   
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Introduction and Aims. Considerable concern has been raised about associations between ecstasy use and mental health. Studies of ecstasy users typically investigate varying levels of lifetime use of ecstasy, and often fail to account for other drug use and sociodemographic characteristics of participants, which may explain mixed findings. The current study aimed to examine the relationship between patterns of recent (last six months) ecstasy use and psychological distress among current, regular ecstasy users, controlling for sociodemographic risk factors and patterns of other drug use. Design and Methods. Data were collected from regular ecstasy users (n = 752) recruited from each capital city in Australia as part of the Ecstasy and related Drugs Reporting System (EDRS). Psychological distress was assessed using the Kessler Psychological Distress Scale (K10). Data were analysed using multinomial logistic regression. Results. Seven per cent of the sample scored in the ‘high’ distress category and 55% in the ‘medium’ distress category. Patterns of ecstasy use were not independently associated with psychological distress. The strongest predictors of distress were female sex, lower education, unemployment, ‘binge’ drug use including ecstasy (use for >48 h without sleep), frequent cannabis use and daily tobacco use. Discussion and Conclusions. Regular ecstasy users have elevated levels of psychological distress compared with the general population; however, ecstasy use per se was not independently related to such distress. Other factors, including sociodemographic characteristics and other drug use patterns, appear to be more important. These findings highlight the importance of targeting patterns of polydrug use in order to reduce drug‐related harm among regular ecstasy users.[George J, Kinner SA, Bruno R, Degenhardt L, Dunn M. Contextualising psychological distress among regular ecstasy users: The importance of sociodemographic factors and patterns of drug use. Drug Alcohol Rev 2010]  相似文献   
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Atrial tachycardias represent the second front of atrial fibrillation (AF) ablation. They are frequently encountered during the index ablation for patients with persistent AF and are common following ablation of persistent AF, occurring in half of all patients who have had AF successfully terminated. An atrial tachycardia is rightly seen as a failure of AF ablation, as these tachycardias are poorly tolerated by patients. This article describes a simple, practical approach to diagnosis and ablation of these atrial tachycardias.  相似文献   
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Mapping of Idiopathic Ventricular Arrhythmias. Background: Termination of ventricular tachycardia (VT) by mechanical pressure has been described for fascicular and postinfarction VT. Mechanical interruption of idiopathic ventricular arrhythmias (VT/premature ventricular complexes [PVCs]) arising in the right ventricular outflow tract (RVOT) has not been described in systematic fashion. Methods: Eighteen consecutive patients (13 females, age 49 ± 13 years, ejection fraction 0.55 ± 0.12) underwent mapping and ablation of RVOT VT or PVCs. In 7 patients, 9 distinct VTs (mean cycle length 440 ± 127 ms), and in 11 patients, 11 distinct PVCs originating in the RVOT were targeted. Mechanical termination was considered present if a reproducibly inducible VT was no longer inducible or if frequent PVCs suddenly ceased with the mapping catheter at a particular location. Endocardial activation time, electrogram characteristics, and pace‐mapping morphology were assessed at this location. Radiofrequency energy was delivered if mechanical termination was observed. Results: All targeted arrhythmias were successfully ablated. In 7 of 18 patients (39%), catheter manipulation terminated the arrhythmia with the mapping catheter located at a particular site. Local endocardial activation time was earlier at sites of mechanical termination (?31 ± 7 ms) compared with effective sites without termination (?25 ± 3 ms, P = 0.04). The 10‐ms isochronal area was smaller in patients with mechanical interruption (0.35 ± 0.2 cm2) than in patients without mechanical termination (1.33 ± 0.9 cm2, P = 0.01). At all sites susceptible to mechanical trauma, the pace map displayed a match with the targeted VT/PVC. All sites where mechanical termination of VT or PVCs occurred were effective ablation sites. Conclusions: Mechanical suppression at the site of origin of idiopathic RVOT arrhythmias frequently occurs during the mapping procedure and is a reliable indicator of effective ablation sites. Mechanical termination of RVOT arrhythmias may be indicative of a more localized arrhythmogenic substrate. (J Cardiovasc Electrophysiol, Vol. 21, pp. 42–46, January 2010)  相似文献   
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Procedural Predictors in SMASH‐VT . Background: The Substrate Mapping and Ablation in Sinus Rhythm to Halt Ventricular Tachycardia (SMASH‐VT) trial is the largest randomized trial in substrate‐based ablation. We performed a retrospective analysis of patients randomized to prophylactic ablation of ventricular tachycardia to determine the predictive value of clinical and procedural variables on outcomes. Methods: In patients treated with catheter ablation, we examined predictors of ICD‐therapy free survival using Cox proportional hazards models. Procedural variables tested included the scar location, number of VT morphologies (VTs) induced, tachycardia cycle length, catheter irrigation, catheter approach, procedural duration, and VT inducibility after ablation. Clinical variables including age, index arrhythmia, NYHA class, ejection fraction, prior revascularization, and baseline medication use were also analyzed. Results: Among 64 patients randomized to ablation, 61 received the assigned therapy and complete procedural data were available for 54 patients. Thirteen percent (7 of 54) experienced ICD therapies during 2‐year follow‐up. Patients with subsequent ICD therapies had significantly more VTs induced during the ablation procedure than those without (3.9 ± 2.1 vs 1.9 ± 1.8, P = 0.05). The hazard ratio for each additional VT induced was 1.51 (95% CI 1.07–2.13, P = 0.02). Two‐year Kaplan–Meier event‐free survival rates were 96% for 0–1 VTs induced, and 78% for two or more. The use of irrigated catheters was not predictive of ablation success. Conclusion: In this small retrospective analysis, the number of VTs induced during the procedure was predictive of 2‐year outcomes. This likely reflects a more complex arrhythmia substrate in patients who fail ablation. (J Cardiovasc Electrophysiol, Vol. pp. 799‐803, July 2010)  相似文献   
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