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61.
The evaluation of a nonsustained wide QRS tachycardia in a life insurance applicant's exercise test presents a special challenge to the medical director because of the unpredictable and potentially lethal nature of these arrhythmias. Ventricular tachycardia accounts for up to 80% of wide QRS tachycardias in unselected populations and more than 95% of cases with a prior myocardial infarction. Malignant ventricular arrhythmias usually occur in the presence of significant structural heart disease. In this setting, ventricular arrhythmias carry a high risk of sudden cardiac death. Less commonly, ventricular tachycardia occurs in hearts that appear normal. In many such cases, however, the heart is in fact not normal, but rather has less visible abnormalities including derangements of cardiac ion channels or structural proteins. In these individuals, ventricular arrhythmias also carry a high risk of sudden cardiac death. There are, however, some ventricular tachycardia syndromes which occur in normal hearts that have a more benign prognosis.  相似文献   
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The presence of unexpected Q waves in an applicant's electrocardiogram poses a diagnostic dilemma for the medical director. On the one hand, the Q waves may be the remnants of a previously unsuspected "silent" myocardial infarction. Conversely, unexpected Q waves may represent a normal or positional variant, or an important noncoronary type of heart disease. This case study illustrates some of the pitfalls in interpreting applicants' electrocardiograms containing Q waves in the inferior leads.  相似文献   
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This paper reviews the evidence on the relationship between work and health. It concludes that, overall, the beneficial effects of work outweigh the risks of work, and are greater than the harmful effects of long-term worklessness. That contrasts with increasing trends of sickness absence, long-term incapacity and ill-health retirement attributed to common health problems. It suggests that there needs to be a fundamental shift in how we think about common health problems and work--in health care, the workplace and society.  相似文献   
64.
Richard Abel argues that in the period from 1910, when the motionpicture "revolution" succeeded and the American film marketwas emancipated from French domination, to 1914, when foreignfilms were nearly eliminated from the U.S. market, the Americanfilm industry was characterized by widespread experimentationand innovation, especially in the areas of promotion practices,distribution strategies, content refinement, and audience development.Six chapters of Abel's Americanizing the Movies bring to theforeground the battle of  相似文献   
65.
Subjects update prior information simultaneously versus sequentially. The mean prediction is remarkably close to the correct Bayesian estimate with simultaneous information, but differs significantly conditional on whether good news precedes bad news or vice versa.  相似文献   
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We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   
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Aims: To assess incremental charges of patients experiencing venous thromboembolisms (VTE) across various types of elective inpatient surgical procedures with administration of general anesthesia in the US.

Methods: The authors performed a retrospective study utilizing data from a nationwide hospital operational records database from July 2014 through June 2015 to compare a group of inpatients experiencing a VTE event post-operatively to a propensity score matched group of inpatients who did not experience a VTE. Patients included in the analysis had a hospital admission for an elective inpatient surgical procedure with the use of general anesthesia. Procedures of the heart, brain, lungs, and obstetrical procedures were excluded, as these procedures often require a scheduled ICU stay post-operatively. Outcomes examined included VTE events during hospitalization, length of stay, unscheduled ICU transfers, number of days spent in the ICU if transferred, 3- and 30-day re-admissions, and total hospital charges incurred.

Results: The study included 17,727 patients undergoing elective inpatient surgical procedures. Of these, 36 patients who experienced a VTE event were matched to 108 patients who did not. VTE events occurred in 0.2% of the study population, with most events occurring for patients undergoing total knee replacement. VTE patients had a mean total hospital charge of $60,814 vs $48,325 for non-VTE patients, resulting in a mean incremental charge of $11,979 (p?<?.05). Compared to non-VTE patients, VTE patients had longer length of stay (5.9 days vs 3.7 days, p?<?.001), experienced a higher rate of 3-day re-admissions (3 vs 0 patients) and 30-day re-admissions (7 vs 2 patients).

Conclusions: Patients undergoing elective inpatient surgical procedures with general anesthesia who had a VTE event during their primary hospitalization had a significantly longer length of stay and significantly higher total hospital charges than comparable patients without a VTE event.  相似文献   
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