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21.

Background  

Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability.  相似文献   
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PURPOSE: To examine longitudinal changes in mood and empathy over the course of the internal medicine residency. METHOD: The authors conducted a cohort study of 61 residents who completed the Profile of Mood States (POMS) and the Interpersonal Reactivity Index (IRI) at six time points during their internal medicine residency at a university-based program. (POMS was administered five times, and IRI was administered six times.) The main outcomes measured were trends in mood disturbances and multiple domains of empathy over the three-year residency, and comparisons to norms. RESULTS: Response rates varied from Time 1 to Time 6 (98%, 72%, 79%, 79%, 94%, and 95%, respectively). Interns had better scores on four POMS subscales: Depression-Dejection (p = .0031), Anger-Hostility (p < .0001), Fatigue-Inertia (p < .0001), and Vigor-Activity (p < .0001) compared with later administrations, especially midinternship. By the end of residency all POMS scores were returning towards baseline (effects sizes in the .20 s), but only depression was no longer significantly different. IRI scores showed the decline in Empathic Concern remained over residency whereas Personal Distress peaked midinternship year but approached baseline at the end of residency. Compared with the general population, the graduating residents were less tense, depressed, and confused. Personal Distress was significantly lower than the norm group. CONCLUSIONS: Internal medicine residency presents challenges resulting in common mood disturbances. Although graduating residents appear to be better off than the population norms, some domains of their mood disturbances and empathy never fully recover from their internship year.  相似文献   
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We studied the effects of dietary NaCl intake on the renal distal tubule by feeding rats high or low NaCl chow or by chronically infusing furosemide. Furosemide-treated animals were offered saline as drinking fluid to replace urinary losses. Effects of naCl intake were evaluated using free-flow micropuncture, in vivo microperfusion, and morphometric techniques. Dietary NaCl restriction did not affect NaCl delivery to the early distal tubule but markedly increased the capacity of the distal convoluted tubule to transport Na and Cl. Chronic furosemide infusion increased NaCl delivery to the early distal tubule and also increased the rates of Na and Cl transport above the rates observed in low NaCl diet rats. When compared with high NaCl intake alone, chronic furosemide infusion with saline ingestion increased the fractional volume of distal convoluted tubule cells by nearly 100%, whereas dietary NaCl restriction had no effect. The results are consistent with the hypotheses that (a) chronic NaCl restriction increases the transport ability of the distal convoluted tubule independent of changes in tubule structure, (b) high rates of ion delivery to the distal nephron cause tubule hypertrophy, and (c) tubule hypertrophy is associated with increases in ion transport capacity. They indicate that the distal tubule adapts functionally and structurally to perturbations in dietary Na and Cl intake.  相似文献   
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This paper describes an innovative approach to preparing high school students with mild disabilities for challenging careers in high tech industries, called High School High Tech (HSHT). Iowa's HSHT Goes to College program has three central elements, each of which is discussed in this paper: High School Preparation—assisting students in identifying a suitable high tech career goal; Higher Education Preparation and Supports—assisting students in selecting college/training programs that match their career goal, and in successfully completing their postsecondary programs; Workforce Entry Assistance—linking students with employers and launching their high tech careers. The paper concludes with a presentation of outcomes to date and recommendations for program enhancements. The information presented here is intended to assist education and rehabilitation professionals interested in establishing similar efforts across the nation.  相似文献   
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Two hundred and thirty pregnancies were studied in 196 diabetic women. Seven women with babies found to have major malformations had a higher median first trimester haemoglobin A1 (12.9%) than the median HbA1 (10.8%) in those with normal babies (p = 0.06). No relationship was found between the occurrence of minor malformations and first trimester maternal haemoglobin A1. Two of the seven congenital malformations were diagnosed antenatally at a time when therapeutic abortion could be offered. Expert antenatal ultrasound scanning should be offered to all pregnant diabetic women as poor glycaemic control at the time of conception and organogenesis, as evidenced by raised first trimester HbA1, predisposes to congenital malformation.  相似文献   
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Wright  John L. 《JAMA》2005,293(11):1301
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The interaction of an organic acid with sodium bicarbonate in water produces an effervescent reaction. The reaction products are carbon dioxide, water, and the sodium salt of the acid. The kinetic rate-determining step for this reaction is the dehydration of carbonic acid. The solid-solid interaction with known amounts of moisture was followed by quantitatively determining carbon dioxide evolution as a function of time. The aqueous solubilities, diffusion coefficients, dissociation constants, and solid-solid interaction rates of six different substituted benzoic acids were determined. Using a model based on diffusion of the organic acid through the aqueous layer coupled with chemical reaction, predicted rates and levels of carbon dioxide production were compared with experimental results. Included in the model were the effects of the reaction products on the solution properties of the reactants. It was found that high concentrations of substituted sodium benzoate were generated very quickly and affected the solubility of the reactants, diffusion coefficient of the acid, and the carbonic acid dehydration rate constant. Moisture content was found to have a profound influence on the interaction rate. Water provides a medium for diffusion of the reacting species as well as the reaction solvent.  相似文献   
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