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In an era of progressive cost containment and public scrutiny, the wisdom of aggressive surgical therapy for high-risk candidates has been questioned. At our center in the previous 24 months, 728 patients with coronary artery disease were entered into The Society of Thoracic Surgeons national database, and the hospital outcomes plus length of stay were analyzed. Patients were separated according to the predicted mortality based on the groupings in The Society of Thoracic Surgeons database: 0 to 5% (453 patients); 5% to 10% (126 patients); 10% to 20% (96 patients); 20% to 30% (17 patients); and 30% and greater (36 patients). There was a close correlation with the predicted rates of mortality. Importantly, the preoperative risk stratification demonstrated a strong correlation with the significant morbidity and excessive length of stay in the highest-risk groups (predicted risk of 20% to > or = 30%). The incidences of the most common complications in the group with the highest predicted risk (> or = 30%) were 28%, renal failure; 33%, ventilator dependence; and 17%, cardiac arrest. In addition, at short-term follow-up (6 to 8 months), a 24.3% mortality was identified in patients with a predicted mortality that exceeded 20%. These data quantify the risks and morbidities associated with the care of seriously ill patients with coronary artery disease and demonstrate the need for professional and public discussions focusing on the association of a high preoperative risk status and the consumption of resources.  相似文献   
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Background: High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period. Although VC is genotoxic, a more comprehensive mode of action has not been determined and diagnostic biomarkers have not been established. The purpose of this study is to address these knowledge gaps through plasma metabolomics. Methods: Plasma samples from polyvinyl chloride polymerization workers who developed hemangiosarcoma (cases, n = 15) and VC exposure-matched controls (n = 17) underwent metabolomic analysis. Random forest and bioinformatic analyses were performed. Results: Cases and controls had similar demographics and routine liver biochemistries. Mass spectroscopy identified 606 known metabolites. Random forest analysis had an 82% predictive accuracy for group classification. 60 metabolites were significantly increased and 44 were decreased vs. controls. Taurocholate, bradykinin and fibrin degradation product 2 were up-regulated by greater than 80-fold. The naturally occurring anti-angiogenic phenol, 4-hydroxybenzyl alcohol, was down-regulated 5-fold. Top affected ontologies involved: (i) metabolism of bile acids, taurine, cholesterol, fatty acids and amino acids; (ii) inflammation and oxidative stress; and (iii) nicotinic cholinergic signaling. Conclusions: The plasma metabolome was differentially regulated in polyvinyl chloride workers who developed hepatic hemangiosarcoma. Ontologies potentially involved in hemangiosarcoma pathogenesis and candidate biomarkers were identified.  相似文献   
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Coherent Doppler lidar for measurements of wind fields   总被引:4,自引:0,他引:4  
The signal-processing techniques for obtaining the velocity estimates and the fundamental factors that influence coherent lidar performance are considered. The similarities and distinctions between Doppler lidar and Doppler radars are discussed. The capability of coherent Doppler lidars for mapping wind fields over selected regions in the lower atmosphere and greatly enhancing the capability to visualize flow patterns in real time is discussed, and examples are given. Salient features of a concept for an Earth-orbiting Doppler lidar to be launched in the late 1990s are examined.<>  相似文献   
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Afour-and-a-half page table summarizes job classifications and salaries of psychologists in the state mental hospital systems of 42 states. The data were acquired by means of a 3-page questionnaire directed to the various mental hospital authorities. "Although functions within state systems vary, indications are that the psychologist continues to find his role in this facet of public service administratively defined as one in which psychodiagnostic skills are primary." Noteworthy, however, "was the extent to which active involvement of the psychologist was also anticipated in the treatment process, research, and teaching of other institutional personnel." 2 states "specified that candidates for their top level positions must possess an ABEPP diploma, and two more expressed the desirability for such… . Twenty-five… states evidenced some enhancement of salary in the form of maintenance or residential perquisites." Major headings in the table refer to: state, job title, educational requirement, professional experience, annual salary, and residential perquisites. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A frequency estimator formed from the peak of a discrete power spectrum is examined. Expressions to compute the performance of the estimator as a function of input signal bandwidth and signal-to-noise ratio are developed and used to study the estimator's capability to measure signal mean frequencies for remote Doppler measurement of atmospheric winds. Performance comparisons with the widely used complex-covariance estimator, based on simulations, show that frequency estimates formed from the spectral peak tend to have larger variance, except in the case of narrow-band input signals where the estimate standard deviation approaches that of the complex-covariance estimator.  相似文献   
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Children with cleft lip and palate require interdisciplinary team care from infancy through adolescence. An understanding of developmental stages allows the cleft palate team to adapt and integrate its services into the rapidly changing life of the child. This article discusses the maturational, developmental stages of childhood and the services the child with cleft lip and palate and the child's family deserve through each stage. Health care providers in all settings may continue to provide appropriate care for all patients with cleft lip and palate, despite the challenges of a changing health care environment, by emphasizing the needs of the child in all developmental stages.  相似文献   
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In this prospective, longitudinal study, 11 recent-onset schizophrenic outpatients who met criteria for psychotic relapse or significant psychotic exacerbation during a 1-year period of standardized maintenance medication, and 19 patients who did not relapse during this follow-up period, were interviewed monthly regarding life events. As hypothesized, for relapsing patients, a significantly higher number of independent life events (those not the result of symptomatology or personal influence) occurred in the month preceding relapse. This increase was apparent relative to either the analogous month of a "nonrelapse" period in the same patient or the average number of independent events per month during a 1-year standardized medication period for nonrelapsing patients. The methodological advances of this design as well as the consistency of these findings with those of previous retrospective studies supports the hypothesis that life events may sometimes "trigger" schizophrenic episodes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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