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81.
Accessory pathways are typically located along the left or right atrioventricular junction. Distinct ventricular pre-excitation patterns determined by surface electrocardiography can provide reasonable pathway localization prior to invasive mapping and catheter ablation. We report an accessory pathway producing an unusual electrocardiographic appearance suggestive of ventricular outflow region pre-excitation. Pacing maneuvers and standard intracardiac recordings confirmed an atrial insertion immediately adjacent to the atrioventricular (AV) node and supported a ventricular insertion at the outflow tract region well away from the AV junction. The elimination of pathway conduction was achieved with radiofrequency (RF) energy at the atrial insertion after successful ice mapping excluded AV block at the target site. This is the second such pathway observed at our institution over a 20-year period.  相似文献   
82.
To stimulate granulopoiesis, we gave recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF; 120 microgram/m2/d) to a patient with congenital neutropenia. The treatment resulted in marked increases in white blood cell counts (maximum, 17,400/microL), consisting mainly of eosinophils (maximum, 13,050/microL) and monocytes (maximum, 1305/microL), rather than neutrophils (maximum, 798/microL). Circulating phagocytes (97% eosinophils) derived after GM-CSF treatment were less effective in chemotaxis, slower but equally effective in phagocytosis, and more effective in H2O2 production compared with normal control neutrophils, but comparable in chemotaxis and H2O2 production to control eosinophils. Before GM-CSF treatment, the bone marrow showed a maturation defect in the neutrophilic series that persisted after treatment despite marked increases in mature cells of other lineages. In vitro agar culture of bone marrow cells before GM-CSF treatment showed a normal number of granulocyte colonies; however, maturation was limited to the metamyelocyte stage. Although the absolute number and cycling rates of myeloid colony forming cells (predominantly eosinophils) increased after treatment, the maturation defect in the neutrophilic series persisted. The finding that GM-CSF induced stimulation of proliferation, which was coupled with maturation in the eosinophilic and monocytic but not the neutrophilic components, suggests that this patient had an intrinsic cellular or humoral defect in neutrophil maturation.  相似文献   
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84.
Objective. To characterize postgraduation placement plans of 2013 doctor of pharmacy (PharmD) graduates.Methods. A cross-sectional survey of PharmD graduates from 8 midwestern colleges of pharmacy was designed to capture a comprehensive picture of graduating students’ experiences and outcomes of their job search.Results. At graduation, 81% of 2013 respondents had postgraduate plans, with approximately 40% accepting jobs and 40% accepting residencies or fellowships. Eighty-four percent of graduates reported being pleased with offers received, and 86% received placement in their preferred practice setting. Students perceived that securing residencies was more difficult than securing jobs. Students who participated in key activities had a nearly sevenfold increase in successful residency placement.Conclusion. While the demand for pharmacists decreased in recent years, responses indicated successful placement by the majority of 2013 graduates at the time of graduation.  相似文献   
85.
Several methods such as the addition of a polar solvent, an acid as well as various post-treatments have been used to improve the thermoelectric performance of conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) films. This paper reports a method using a superacid, trifluoromethanesulfonic acid, in methanol to treat PEDO:PSS films to improve their thermoelectric performance. Treatment of PEDOT:PSS films with this superacid in methanol leads to a significant increase in electrical conductivity from 0.7 to 2980 S cm−1 together with a moderate increase in Seebeck coefficient from 17.6 to 21.9 μV K−1, giving a power factor of 142 μW m−1 K−2, one of the highest values reported in the literature for conductive polymers. The figure of merit (ZT) value is estimated to be 0.19 under optimized conditions. The enhancement of thermoelectric performance, particularly the increase in both electrical conductivity and Seebeck coefficient, is due to the removal of the insulating component and polymer chain realignment giving in turn a denser packing of the conductive PEDOT polymer chains. This post-treatment method would offer an alternative way to improve the thermoelectric performance.

Treatment of PEDOT:PSS films with a superacid results in remarkable improvement of thermoelectric performance with a power factor of 142 μW m−1 K−2.  相似文献   
86.
Heart Failure Reviews - Acute decompensated heart failure (ADHF) accounts for more than 1 million hospital admissions annually and is associated with high morbidity and mortality. Decongestion with...  相似文献   
87.
88.
Androgen therapy may precipitate obstructive sleep apnea in men. Despite increasing androgen use in older men, few studies have examined sleep and breathing. Randomized, double-blind, placebo-controlled studies examining effects of testosterone simultaneously on sleep, breathing, and function in older men are not available. Seventeen community-dwelling healthy men over the age of 60 yr were randomized to receive three injections of im testosterone esters at weekly intervals (500 mg, 250 mg, and 250 mg) or matching oil-based placebo and then crossed over to the other treatment after 8 wk of washout. Polysomnography, anthropometry, and physical, mental, and metabolic function were assessed at baseline and after each treatment period. Testosterone treatment reduced total time slept ( approximately 1 h), increased the duration of hypoxemia ( approximately 5 min/night), and disrupted breathing during sleep (total and non-rapid eye movement respiratory disturbance indices both increased by approximately seven events per hour) (all P < 0.05). Despite expected effects on body composition (increase in total and lean mass, reduction in fat mass, P < 0.05, bioimpedance method), upper airway dimensions did not change (acoustic reflectometry). Driving ability (computer simulation), physical activity (accelerometry, Physical Activity Scale in the Elderly), quality of life (SF36, Functional Outcomes of Sleep Questionnaire), mood (Profile of Mood States Questionnaire), sleepiness (Epworth, Stanford scales), and insulin resistance (homeostasis model) also were not changed by treatment. Short-term administration of high-dose testosterone shortens sleep and worsens sleep apnea in older men but did not alter physical, mental, or metabolic function. These changes did not appear to be due to upper airway narrowing. Further study of longer-term lower-dose androgen therapy on sleep and breathing is needed to evaluate its safety in older men.  相似文献   
89.
90.

Objectives

The purpose of the current study was to determine the optimal duration of external loop recorder (ELR) monitoring in patients with presyncope or syncope and to identify factors that predict failure to activate the device effectively.

Design

A multivariate analysis was performed using data from the Comparison Of Loop Recorders Against Holter in Patients with Syncope (COLAPS) trial, a prospective study comparing diagnostic utility of ELRs and Holter monitors for assessment of syncope.

Methods

Patients with failure to effectively activate ELRs were compared to those who were successful. This analysis was performed separately for failure of test transmission and for failure to successfully record and transmit data from symptomatic episodes. Patient characteristics were compared among the groups to determine risk factors for device failure.

Results

Among 78 patients who received ELRs, a test transmission was successfully performed by 84.5% of patients. Twenty-one percent of diagnoses were made within 48 hours, 50% at 15 days, and 90% at 33 days. Patients performing a successful test transmission were more familiar with technology, with ability to use a bank automatic teller machine being a significant independent predictor. Patients with a successful test transmission were, in turn, significantly more likely to record and transmit data from symptomatic episodes. Patients living alone were much less likely to use the loop recorder effectively. The presence of factors that may influence motivation to reach a diagnosis (degree of worry/fear of symptoms and impact on daily life) were associated with successful use of the device in a univariate analysis.

Conclusion

ELRs should be worn for at least 30 days to maximize their diagnostic yield. Patients who are unfamiliar with technology, live alone, or have low motivation to reach a diagnosis have a lower diagnostic yield from ELRs for assessment of syncope.  相似文献   
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