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41.
42.
While much has been made of the governmentality evinced in drug policy, its effects on people who use drugs have received less attention. Scholars who have investigated these effects commonly focus on the views and experiences of individuals receiving treatment for their drug use, often reporting an explicit desire among individuals in treatment for a return to a normal, healthy life. Many authors trace this desire to the normalisation inherent in drug policy, and the governmentality involved in the delivery of drug treatment more directly. This article adds to these discussions by shifting focus from the experience of individuals in treatment to those out of treatment settings. In so doing, we aim to develop a more nuanced understanding of how heavy drug users negotiate power, governmentality and the modulations of health and illness in the course of everyday life. We ground our discussion in qualitative research conducted in Melbourne, Australia, with 31 current methamphetamine consumers. We argue that regular methamphetamine consumption involves a complex and ambivalent relationship with the ideas of health and normal life, imposing as well as reflecting a form of estrangement between its consumers and mainstream (or normal) society. This ambivalence has important implications for the delivery of health and social services among methamphetamine consumers, insofar as the restoration of normal health and the reintegration of former drug users into mainstream society are typical health service goals. We address some of these policy implications by way of conclusion.  相似文献   
43.
OBJECTIVES: The goal of this study was to identify subgroups of arrhythmia patients who do not benefit from use of the implantable cardiac defibrillator (ICD). BACKGROUND: Treatment of serious ventricular arrhythmias has evolved toward more common use of the ICD. Since estimates of the cost per year of life saved by ICD therapy vary from $25,000 to perhaps $125,000, it is important to identify patient subgroups that do not benefit from the ICD. METHODS: Data for 491 ICD patients enrolled in the Antiarrhythmics Versus Implantable Defibrillators Study were used to create a hazards model relating baseline factors to time to first recurrent arrhythmia. The model was used to predict the hazard for recurrent arrhythmia among all trial patients. A priori cut points provided lower and higher recurrent arrhythmia risk strata. For each stratum the incremental years of life due to ICD versus antiarrhythmic drug therapy were calculated. RESULTS: Factors that predicted recurrent arrhythmia were: ventricular tachycardia as the index arrhythmia, history of cerebrovascular disease, lower left ventricular ejection fraction, a history of any tachyarrhythmia before the index event and the absence of revascularization after the index event. Survival times (over a follow-up of three years) were identical in each arm of the lowest risk sextile (survival advantage 0.03 +/- 0.12 [se] years), while the survival advantage for patients above the first sextile was 0.27 +/- 0.07 (se) years (two-sided p = 0.05). CONCLUSIONS: Patients presenting with an isolated episode of ventricular fibrillation in the absence of cerebrovascular disease or history of prior arrhythmia who have undergone revascularization or who have moderately preserved left ventricular function (left ventricular ejection fraction > 0.27) are not likely to benefit from ICD therapy compared with amiodarone therapy.  相似文献   
44.
To test the hypothesis that scans with technetium-99m pyrophosphate (Tc-99m-PPi) are positive when performed early after successful thrombolytic therapy for acute myocardial infarction (AMI), 16 consecutive patients with AMI who received thrombolytic therapy within 5 hours after the onset of chest pain were studied. Patients were included if chest pain lasted for greater than 30 minutes, was unresponsive to sublingual nitroglycerin and was associated with at least 0.2 mV ST-segment elevation in at least 2 contiguous electrocardiographic leads. All patients received 1.5 million IU of streptokinase intravenously, a mean of 195 +/- 99 minutes after onset of chest pain. Tc-99m-PPi scans and coronary cineangiograms were recorded 491 +/- 156 minutes and 518 +/- 202 minutes, respectively, after the onset of symptoms. Effective reperfusion was present in 10 patients, 6 of whom had positive Tc-99m-PPi scans (sensitivity of 60% to detect reperfusion). Of the 6 patients without effective reperfusion, 3 had positive Tc-99m-PPi scans (specificity of 50%, p greater than 0.05). Analysis of the data using various definitions of effective reperfusion or artery patency yielded similar results. Thus, our findings indicate that early AMI scanning with Tc-99m-PPi does not accurately detect the presence or absence of reperfusion in patients with AMI after treatment with intravenous streptokinase. At this time, coronary cineangiography is the only reliable method to detect reperfusion promptly after thrombolytic therapy.  相似文献   
45.
Only two cases have been reported previously of the association of ventricular septal defect (VSD) with anomalous origin of the left coronary artery (ALCA) arising from the pulmonary artery. The purpose of this paper is to present two additional cases, to describe the pathophysiology, and to emphasize how the clinical course of this combination of defects differs from that of isolated ALCA. Patients with both of these anomalies present in infancy with manifestations only of a large left-right ventricular shunt and pulmonary hypertension. Initially the ALCA is well perfused from the high pressure in the pulmonary artery. In these instances in which the pulmonary artery pressure subsequently decreased because of spontaneous reduction in size of the VSD, the left coronary arterial system became less well perfused. Because of this decreased perfusion in association with the left ventricular myocardial stress initially caused by volume overload, myocardial ischemia and ultimately infarction occurred. Early identification and repair of the anatomic abnormality could prevent irreversible myocardial damage.  相似文献   
46.
Transseptal left heart catheterization was performed in 80 infants and children with various forms of congenital heart disease. The majority had left heart obstructive lesions. Forty percent were under 5 years of age and less than 20 kg in weight. Uncomplicated cardiac perforation occurred in two patients. The technique is described in detail with emphasis on measures which increase the safety of the procedure for the patient. We conclude that this is a useful technique and in selected patients may be the preferred approach to the left heart.  相似文献   
47.
A crossover comparison of intravenous procainamide, disopyramide and quinidine was made in 32 patients. All three drugs had dosage-related effects on electrocardiographic intervals, refractory periods and cycle length of ventricular tachycardia. Significant linear relations between serum drug levels and changes in refractory periods and ventricular tachycardia cycle length were also observed. Ventricular tachycardia was no longer inducible on at least one drug in 11 patients but concordance of this effect on both of the others was 36% and on either of the others it was 45%. Ventricular tachycardia remained inducible on at least one drug in 28 patients and concordance of this effect on both of the others was 75% and on either of the others was 79%. Continued inducibility on quinidine, the drug producing the greatest electrophysiologic effects, was the best individual predictor of continued inducibility on the others. Subdivision of continued inducibility into easier to induce, inducibility unchanged, or harder to induce dramatically decreased concordance of this effect. Thus the antiarrhythmic effects of these drugs are discordant in individual patients despite electrophysiologic similarities. Nevertheless, continued inducibility after high dosages of any one of these drugs is clinically useful for screening for continued inducibility on the others and this is dose-related rather than drug specific.  相似文献   
48.
Propranolol has been effective in suppressing ventricular arrhythmias in up to 70% of patients in some series; however, a wide range of concentrations was required to produce this degree of efficacy. In one series, 40% of responders required high serum concentrations (greater than 500 ng/ml) in excess of those required for physiologic beta-receptor blockade (25 to 150 ng/ml). To assess the relative contribution of high concentration electrophysiologic effects to antiarrhythmic efficacy the results of programmed electrical stimulation were compared at high and low (beta-blocking) concentrations in 28 patients with inducible sustained ventricular tachycardia. Propranolol was given as a series of loading and maintenance infusions producing first a mean concentration of 130 +/- 72 ng/ml (beta-blocking) and then a mean concentration of 743 +/- 523 ng/ml (high). Beta-blockade was assessed by the percent reduction in exercise-induced tachycardia. Near maximal beta-blockade was achieved by a concentration of 150 ng/ml. At a low concentration, 6 of 28 patients had a response to propranolol (complete in 5 and partial in 1). At a high concentration, one additional patient had a complete response while three had a partial antiarrhythmic response. At high concentrations of propranolol there was a significant shortening of the QTc interval relative to that seen during the low dose infusion. No other significant electrophysiologic changes occurred at high versus low concentration. In summary, an antiarrhythmic response to propranolol occurs most frequently at a beta-blocking concentration. High concentration electrophysiologic effects occur and these appear to contribute to antiarrhythmic efficacy in some patients.  相似文献   
49.

Purpose

Patients with suspected deep vein thrombosis (DVT) are often managed on an outpatient basis. The aim of the study was to validate a clinical prediction rule specifically for use in primary care to help physicians in their decision to start anticoagulant therapy while awaiting ultrasound examination.

Patients and methods

Between September 2007 and October 2008, 194 general practitioners prospectively included patients with clinically suspected DVT without clinically suspected pulmonary embolism. All patients underwent a standardized clinical assessment in order to collect items included in the clinical prediction rule (personal history of venous thromboembolism +1, immobilization in previous month +1, estrogen contraceptive +2, active malignancy +3, swelling of the calf +1, the presence of an alternative diagnosis more likely than that of DVT–3. DVT unlikely if score < 2, likely if score ≥ 2).

Results

Among the 164 included patients, 56 (34%) had DVT of them 28 (17%) had a proximal DVT. Proportions of confirmed DVT were 29% in the unlikely group and 43% in the likely group against 26% and 63% respectively in the derivation study.

Conclusions

This clinical prediction rule might not fulfill the required conditions to be considered as a usable help in the ambulatory management of DVT. Variations of the cut-off value could enhance its performance.  相似文献   
50.
Cognitive change following bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) surgery in those with Parkinson's disease (PD) has led to equivocal results. The current study applied a standardized regression-based (SRB) method based on 20 medically managed PD patients and 20 STN DBS PD surgical patients who were administered the Repeatable Battery of Neuropsychological Status (RBANS). Of the medically managed PD participants, 94% remained stable compared to 73% of the DBS group. In the DBS group cognitive change was noted on the Total scale and the Immediate Memory Index. A secondary analysis also revealed reliable change on several subtest scores. Although preliminary, the current study provides change parameters for post DBS surgery on this brief battery.  相似文献   
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