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991.
Mucositis is a common side effect related to the treatment of cancer. Many agents have been tested for the prevention and management of mucositis, but the data regarding a number of the agents are conflicting. This article describes the incidence of mucositis in individuals with cancer and the various agents used in its prevention and management. Nurses play an important role in the management of patients with mucositis and in identifying agents that may decrease the patient's risk for mucositis and aid healing.  相似文献   
992.
993.
BACKGROUND: Although it has been previously reported that offering continuing medical education (CME) credit is not a major factor in tumor board attendance, the results/utility of the Accreditation Council for Continuing Medical Education mandated evaluations of those tumor boards offering CME credit has not been studied. METHODS: We reviewed the CME evaluations of our University Gastrointestinal Tumor Board; this meeting was chosen because it is multidisciplinary, well attended, and offers CME credit contingent on completing a standard CME evaluation form each session. RESULTS: Of the 2736 attendees, 660 (24%) at the 79 consecutive conferences studied completed the evaluation for CME credit. Reported satisfaction was high; the average response on the 4-question satisfaction survey was 5 (Excellent) on a 5-point Likert scale, only 6% of attendees perceived any commercial bias, and only 3 attendees stated that the conference did not achieve the stated objectives. Of the respondents, 42% indicated that the tumor board information would change their practice, although few specific examples were given. A minority of responders provided specific feedback. CONCLUSIONS: A minority of attendees at this tumor board utilized CME credit. Although satisfaction and impact ratings were high, potential response set bias, lack of specific feedback, and nonresponse bias were limitations to the evaluations.  相似文献   
994.
The pharmacodynamics of ciprofloxacin were explored in an in-vitro continuous bacterial culture model of infection, by simulating two oral dosing regimens; 0.5 g 12-hourly (bd) and 1 g 24-hourly (od). Three strains of Escherichia coli (ciprofloxacin MICs 0.03, 0.5 and 2 mg/L); two strains of Pseudomonas aeruginosa (MICs 0.09 and 1.5 mg/L), two strains of Staphylococcus aureus (MICs 0.12 and 1 mg/L) and two strains of Streptococcus pneumoniae (MICs 0.5 and 2 mg/L) were used. Three pharmacodynamic parameters, T > MIC, C(max)/MIC and AUC/MIC (T = time, C(max) = peak serum concentration, AUC = area under the curve), were compared with area under the bacterial-kill curve (AUBKC) (after transformation of the AUBKC) using a simple E(max) or sigmoidal E(max) model. AUBKC was taken to be the main antibacterial effect measure. The models were compared by inspection of residuals and Akaike information criterion. E(max) models adequately described the relationship between AUC/MIC and AUBKC and between C(max)/MIC and AUBKC, but not between T> MIC and AUBKC. All three pharmacodynamic parameters are related to each other but multiple regression analysis indicated that AUC/MIC was the best individual predictor of AUBKC. Despite this, comparison of od and bd regimens indicates some advantage to od in terms of early antibacterial effect. Serum concentration-time curve shape has some importance in determining antibacterial effect. These data indicate that for ciprofloxacin AUC/MIC ratio is not the sole determinant of antibacterial effect.  相似文献   
995.
SECOND OPINION     
Rob Rogers 《Chest》2008,133(1):12
  相似文献   
996.
The authors report a new side effect of the dopamine agonists pramipexole and ropinirole: sudden irresistible attacks of sleep. Eight PD patients taking pramipexole and one taking ropinirole fell asleep while driving, causing accidents. Five experienced no warning before falling asleep. The attacks ceased when the drugs were stopped. Neurologists who prescribe these drugs and patients who take them should be aware of this possible side effect.  相似文献   
997.
Inhaled nitric oxide is a potent and selective pulmonary vasodilator. However, when used in patients with congestive cardiac failure, the decrease in pulmonary vascular resistance is associated with an increase in pulmonary capillary wedge pressure (PCWP). This study examined load-independent indexes of left ventricular chamber function during inhaled nitric oxide in 10 patients with dilated cardiomyopathy (mean ejection fraction, 30.2+/-7.8%, mean +/- SD). Etiology of cardiomyopathy was idiopathic in six and ischemic in four. Pulmonary hemodynamics in seven patients revealed normal resting pulmonary vascular resistance. Chamber function was defined by recording pressure-volume loops at steady state and during inferior vena caval occlusion during inhalation of 20 ppm nitric oxide for 10 min. We found no effect of inhaled nitric oxide on steady-state left ventricular pressures, volumes, contractility (end-systolic elastance or preload recruitable stroke work), contraction duration, or active (tau, dP/dt(min)) or passive (end-diastolic pressure-volume relation) diastolic function. Right heart filling pressures did not change. We therefore conclude that 20 ppm inhaled nitric oxide does not affect left ventricular chamber function in patients with controlled heart failure. Previously described elevations in PCWP during inhaled nitric oxide are most likely due to altered left ventricular loading conditions related to secondary pulmonary hypertension in severe heart failure.  相似文献   
998.
Arsenic was detected in 22 of 525 samples of fruits, vegetables, grain products, fast foods, dairy products, and seafoods analyzed by a multielement X-ray fluorescence method. The arsenic occurrences corresponded almost completely and exclusively with seafoods, and the correspondence was confirmed by additional analyses of separated parts of fast-food fish sandwiches. The geometric mean arsenic concentration for all seafoods was 2.1 μg/g (dry weight), with a geometric standard deviation of 3.2. Relative analytical precisions averaged 5.9% standard deviation, and arsenic inhomogeneity among sample aliquots averaged 4.5%. Accuracies validated by six National Institute of Standards and Technology reference materials averaged within 0.2 μg/g, or 5.1 % of certified values, with a net bias of less than 0.1 μg/g. Total arsenic contents in single servings of the seafoods (geometric MEAN = 109 μg) may account completely for the average U.S. arsenic intake if one serving is consumed every 2 to 10 days. Average total arsenic contents are similar among single servings of fish sandwiches, fish fillets, shrimp, and clam chowder; however, variation among specific samples of these seafoods amounts to a factor of 2 to 3. Arsenic concentrations in fish and shrimp agree with values predicted from bioaccumulation from seawater, suggesting consistency with a broader range of seafoods.  相似文献   
999.
1000.
Previous studies have demonstrated that dietary administration of the schistosomicidal drug 5-(2-pyrazinyl)-4-methyl-1,2-dithiole-3-thione (oltipraz) ameliorates the hepatotoxicity of aflatoxin B1 (AFB1). Notably, mortality, altered hepatic function, hepatic AFB1-DNA adduct levels, and expression of hepatic enzyme-altered foci were markedly reduced in the rat by concurrent feeding of oltipraz during exposures to AFB1. Collectively, these studies prompted us to evaluate the chemoprotective properties of oltipraz against AFB1-induced liver cancer. In addition, preliminary molecular dosimetry studies were undertaken to determine the utility of measurements of urinary aflatoxin-N7-guanine excretion as a marker of relative risk for hepatocarcinogenesis in AFB1-exposed rats. For the carcinogenesis studies, 5-wk-old male F344 rats were randomly divided into two groups. One group (55 rats) received the AIN-76A diet, and the other group (56 rats) received the AIN-76A diet supplemented with 0.075% oltipraz. The oltipraz-supplemented diet was fed for 4 wk. Beginning 1 wk after starting the experimental diets, all rats in both groups received 25 micrograms of AFB1/rat/day by gavage for 5 days per wk over the next 2 wk. One wk following cessation of dosing with AFB1, oltipraz was removed from the diet, and all rats were fed the AIN-76A diet for the remainder of the experiment. At 3 mo after dosing, livers of ten sentinel rats from each group were analyzed for the burden of gamma-glutamyltranspeptidase-positive foci. In accord with previous findings, rats fed the oltipraz-supplemented diet exhibited substantial reductions in the focal burden (97% reduction; P less than 0.05) of these AFB1-induced lesions. The remaining rats were maintained for the cancer study until they became moribund or the termination of the experiment at 23 mo. Gross liver lesions were identified at autopsy and confirmed by microscopic evaluation. An 11% incidence of hepatocellular carcinoma was observed in the AFB1-treated, control diet-fed rats. An additional 9% of this group had hepatocellular adenomas. Oltipraz afforded complete protection against both AFB1-induced hepatocellular neoplasms. Using Kaplan-Meier survival analyses, rats in the oltipraz group had a significantly (P less than 0.02) longer life span and an increased survival free of liver tumors (P less than 0.0002). Molecular dosimetry studies used rats fed either the oltipraz-supplemented or control diet for 1 wk and then challenged with a single dose of AFB1 to examine the initial rates of 8,9-dihydro-8-(N7-guanyl)-9-hydroxyaflatoxin B1 excreted in the urine.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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