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Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia. There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously.  相似文献   
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The postantibiotic effect (PAE) of clarithromycin alone and in combination with ethambutol was determined for two clinical blood isolates of Mycobacterium avium complex. An average PAE, ranging from 5.5 to 18.0 h, was noted for each isolate at each clarithromycin concentration except when isolate B was exposed to clarithromycin at the MIC. The addition of ethambutol did not enhance the PAE observed with clarithromycin alone. The clinical implications of the PAE of clarithromycin for M. avium complex remain to be determined.  相似文献   
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Urea rebound and delivered Kt/V determination with a continuous urea sensor   总被引:3,自引:1,他引:2  
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring has made possible new approaches to urea kinetic modelling. In this study we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V corrected for double-pool urea kinetics (Kt/Vdp) can be accurately determined using an on-line sensor providing a continuous measure of blood water urea. A modification of the Smye constant volume double-pool theory led to the following equations for Ceq and Kt/Vdp [formula: see text] where Cpre is the blood concentration measured at the start of dialysis, t is the length of the dialysis session (in min) and S(ex) is the constant slope of the blood urea logarithm concentration decline following development of the intercompartmental urea concentration gradient in the first 30-60 min of dialysis. METHODS: These equations were tested in 11 patients undergoing 165-240 min of paired filtration dialysis with continuous monitoring of blood urea concentration. Cpre was determined as the plateau concentration during a preliminary period of 15-20 min of slow isolated ultrafiltration. S(ex) was accurately determined from linear regression applied to the urea sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and Kt/Vdp determined from the above equations compared closely to values determined from 25-40 min of urea rebound monitoring with the urea sensor: 10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/- 0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed into on-line urea monitors to provide current and extrapolated values of Ceq and Kt/Vdp from about the first hour of dialysis.   相似文献   
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This paper reports (1) a method for classifying students according to the breadth of their premedical preparation and (2) a comparison of the medical school performances and career plans of the students thus classified. The method was developed in 1987, in part by using input from a small but representative sample of admission officers. Students were grouped according to undergraduate major, ratio of nonscience-to-science course hours, and extracurricular involvement. After tentatively classifying all individuals who had entered U.S. medical schools in 1981 as having either broad or science-focused preparation, the author compared the two most distinct groups selected from a random sample of the individuals in each classification: 59 individuals constituted the final broadly prepared group, and 73, the science-focused group. The science-focused group attained higher mean scores (p less than .05) on three science sections of the National Board of Medical Examiners (NBME) Part I examination, and the broadly prepared group scored higher on the Behavioral Sciences section (p less than .05). No other significant difference was evident between the groups' mean scores on the NBME Parts I, II, or III, or in the groups' rates of experiences of academic difficulty, specialty choice distributions, or percentages of individuals deciding to pursue research careers. The author concludes that this method of classifying students is useful and that the students with less premedical focus in the sciences were able to perform well.  相似文献   
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One thousand and eleven men under age forty (n = 161) or over age sixty-four (n = 850) admitted to medical and neurological services of an acute care hospital were screened for depressive symptoms as part of the Durham VA Mental Health Survey. Thirty-three percent of younger and 22 percent of older men scored 11 or higher on the Geriatric Depression Scale. Self-rated symptoms were most prevalent among younger whites (40%) and least common in older blacks (19%). Other exogenous factors such as being retired or unemployment and prior psychiatric history were also related to depressive symptoms, as were poor functional status, impaired cognitive status, and respiratory illness. Coping resources associated with fewer symptoms were social support and moderate alcohol use. In a subgroup of 443 patients, self-rated symptoms were compared with observer-rated symptoms. Agreement was highest among young Whites and lowest in older Blacks. Other correlates also varied depending on whether self-rated or observer-rated symptoms were considered. We conclude that self-rated symptoms are common among medical inpatients, are linked with and confounded by certain health and sociodemographic factors, and may be relatively insensitive as a measure of depression in elderly blacks.  相似文献   
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