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991.
OBJECTIVE: To examine the errorless learning approach using a procedural memory task (i.e. learning of actual routes) in patients with amnesia, as compared to trial-and-error learning. DESIGN: Counterbalanced self-controlled cases series. SETTING: Psychiatric hospital (Korsakoff clinic). SUBJECTS: A convenience sample of 10 patients with the Korsakoff amnestic syndrome. INTERVENTION: All patients learned a route in four sessions on separate days using an errorless approach and a different route using trial-and-error. MAIN MEASURES: Error rate was scored during route learning and standard neuro-psychological tests were administered (i.e. subtest route recall of the Rivermead Behavioural Memory Test (RBMT) and the Dutch version of the California Verbal Learning Test (VLGT)). RESULTS: A significant learning effect was found in the trial-and-error condition over consecutive sessions (P = 0.006), but no performance difference was found between errorless and trial-and-error learning of the routes. VLGT performance was significantly correlated with a trial-and-error advantage (P < 0.05); no significant correlation was found between the RBMT subtest and the learning conditions. CONCLUSION: Errorless learning was no more successful than trial-and-error learning of a procedural spatial task in patients with the Korsakoff syndrome (severe amnesia).  相似文献   
992.
993.

Introduction

The male-to-female transgender (waria) is part of a key population at higher risk for HIV. This study aims to test whether psychosocial determinants as defined by the theory of planned behaviour (TPB) can explain behaviours related to condom use among waria. Three preparatory behaviours (getting, carrying, and offering a condom) and two condom use behaviours (during receptive and insertive anal sex) were assessed.

Methods

The study involved 209 waria, recruited from five districts in Jakarta and interviewed by using structured questionnaires. Specific measures were developed to study attitudes, subjective norms and perceived behavioural control (PBC) in order to predict intentions and behaviours.

Results

The explained variance between intentions with regard to three preparatory behaviours and two condom uses ranged between 30 and 57%, and the variance between the actual preparatory behaviours of three preparatory and two condom uses ranged between 21 and 42%. In our study, as with several previous studies of the TPB on HIV protection behaviours, the TPB variables differed in their predictive power. With regard to intention, attitude and PBC were consistently significant predictors; attitude was the strongest predictor of intention for all three preparatory behaviours, and PBC was the strongest predictor of intention for condom use, both during receptive and insertive anal sex. TPB variables were also significantly related to the second parameter of future behaviour: actual (past) behaviour. TPB variables were differentially related to the five behaviours. Attitude was predictive in three behaviours, PBC in three behaviours and subjective norms in two behaviours.

Conclusions

Our results have implications for the development of interventions to target preparatory behaviours and condom use behaviours. Five behaviours and three psychological factors as defined in the TPB are to be targeted.  相似文献   
994.
Distal embolic event is one of the major limitations of coronary and non‐coronary vascular interventions. Balloon and filter‐based Embolic Protection Devices (EPDs) are a new class of interventional devices, used to prevent consequential morbidity and mortality of the distal embolic events. Data from first generation EPD supply proof of concept and show approximately 40% reduction in mortality and morbidity, when EPDs are used during saphenous vein grafts (SVGs) interventions. Current limitations of all first generation EPD technology taper their penetration. With breakthroughs in embolic protection technology, it is estimated that, in the near future, EPDs will be used with stenting in all high‐risk lesions (SVGs, carotid arteries and acute coronary syndromes), become the standard of care and even be used in low risk cases.  相似文献   
995.
The use of an arteriovenous graft as vascular access for hemodialysis is associated with a high rate of patency loss. The influence of timing of the first cannulation of the graft on graft survival has not been sufficiently studied. The purpose of this study was to investigate an association between the timing of the first cannulation of the polytetrafluoroethylene arteriovenous graft and the incidence of 12‐month failure. This is a retrospective study on a cohort of chronic hemodialysis patients treated in a single center. According to the time, in weeks, between graft construction and its first successful cannulation, the grafts were divided into six groups: 2nd, 3rd, 4th, 5th, 6th and 7th or more week after surgery. The primary outcome was primary graft failure at 12 months, defined as the first occurrence of graft thrombosis or any invasive access procedure. The secondary outcome was cumulative graft failure at 12 months, defined as complete loss of the access site for dialysis. Fifty‐eight patients with 64 newly‐created arteriovenous grafts were included in the study. In the whole cohort, the incidence of primary graft failure at 12 months was 72.2%, and the incidence of cumulative graft failure at 12 months was 40.7%. The incidences of primary graft failure and cumulative graft failure at 12 months did not differ significantly between the study groups. In our study, timing of the first cannulation of a new arteriovenous polytetrafluoroethylene graft had no significant impact on graft survival.  相似文献   
996.
OBJECTIVES. Herein, we investigated the percentage of T‐helper (Th1) and Th2 cells among the general T‐cell population in the peripheral blood of patients with stable angina (SA) and unstable angina (UA). BACKGROUND. Recent evidence suggests that Th1 cells and the cytokines that they secrete (especially IFN‐γ) have a role in the activation of macrophages, promotion of clot formation and destabilization of atherosclerotic plaques. Thus, Th1 cytokines may contribute to the initiation and progression of UA. In contrast, cytokines secreted by Th2 cells (e.g. IL‐10) are known to inhibit activation and proliferation of Th1 cells and the secretion of IFN‐γ, lysosomal enzymes and metalloproteinases. Therefore, we sought to examine whether the ratio of IFN‐γ to IL‐10 secreting cells is altered in patients with UA. METHODS. The percentage of Th1 and Th2 cells among the general T‐cell population was determined by fluorescent intracellular cytokine staining (IFN‐γ and IL‐10, out of the total CD3 positive cells). RESULTS. The percentage of T‐cells positive for intracellular IFN‐γ was significantly higher in patients with UA (n = 22) in comparison with SA (n = 20) patients (39.0±2.8% and 29.6±2.7%, respectively. P = 0.02). There was no significant difference in intracellular IL‐10 positive cells between the two groups. In addition, there was no significant difference in the ratio between the intracellular IFN‐γ positive cells and the intracellular IL‐10 positive cells. CONCLUSIONS. There is an increased activity of Th1 cells in patients with UA in comparison with patients with SA. There is no evidence of heightened activity of Th2 cells in either group. Thus, IFN‐γ secreted by peripheral blood T‐lymphocytes,may be an important immunomodulator contributing to destabilization of the atheromatous plaque lying at the base of the etiopathogenesis of unstable angina.  相似文献   
997.
998.

Objective

To assess the mid-term efficacy of magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) using a volumetric ablation technique for treating uterine fibroids.

Methods

Forty-six premenopausal women with 58 symptomatic uterine fibroids were prospectively included for MR-HIFU. After treatment, CE-MRI allowed measurement of the non-perfused volume (NPV) ratio, defined as the non-enhancing part of the fibroid divided by fibroid volume. Clinical symptoms and fibroid size on T2W-MRI were quantified at 3 and 6 months’ follow-up. The primary endpoint was a clinically relevant improvement in the transformed Symptom Severity Score (tSSS) of the Uterine Fibroid Symptom and Quality of Life questionnaire, defined as a 10-point reduction.

Results

Volumetric ablation resulted in a mean NPV ratio of 0.40 ± 0.22, with a mean NPV of 141 ± 135 cm3. Mean fibroid volume was 353 ± 269 cm3 at baseline, which decreased to 271 ± 225 cm3 at 6 months (P?<?0.001), corresponding to a mean volume reduction of 29 % ± 20 %. Clinical follow-up showed that 54 % (25/46) of the patients reported a more than 10-point reduction in the tSSS. Mean tSSS improved from 50.9 ± 18.4 at baseline to 34.7 ± 20.2 after 6 months (P?<?0.001).

Conclusion

Volumetric MR-HIFU is effective for patients with symptomatic uterine fibroids. At 6 months, significant symptom improvement was observed in 54 % of patients.

Key Points

? Volumetric MR-guided high-intensity focused ultrasound is a novel ablation technique for leiomyomatosis. ? We prospectively evaluated the outcome of volumetric MR-HIFU ablation for symptomatic fibroids. ? This study showed that volumetric MR-HIFU results in an effective treatment. ? A randomised controlled trial would set this technique in an appropriate context.  相似文献   
999.
1000.
This study describes the prevalence of postpartum post-traumatic stress disorder (PTSD) based on the DSM-IV criteria, including its symptoms of intrusion, avoidance and hyperarousal after pregnancies complicated by preeclampsia, and examines which variables are associated with PTSD and its symptoms. Women whose pregnancies were complicated by preeclampsia completed the Self-Rating Inventory for PTSD at 6 and 12 weeks postpartum: 149 women completed this questionnaire on at least one time point. Logistic regression analyses were used to examine associations with PTSD and its symptoms. Results showed that the prevalence of PTSD was 8.6% at 6 weeks, and 5.1% at 12 weeks postpartum; 21.9% of the study sample experienced postpartum symptoms of intrusion at 6 weeks postpartum (11.7% at 12 weeks), 9.4% symptoms of avoidance (8.0% at 12 weeks), and 28.9% symptoms of hyperarousal (20.4% at 12 weeks). Younger age, severe preeclampsia, cesarean section, lower gestational age, lower birth weight, admission to the neonatal intensive care unit, and perinatal death were found to be associated with PTSD and its symptoms. There was a relatively high prevalence of postpartum symptoms of PTSD among women after preeclampsia. The prevalence was highest among younger women who experienced more adverse pregnancy outcomes.  相似文献   
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