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981.
Adverse hemodynamic and clinical effects of encainide in severe chronic heart failure 总被引:1,自引:0,他引:1
STUDY OBJECTIVE: To evaluate the hemodynamic effects of the antiarrhythmic drug, encainide, in patients with severe chronic heart failure. DESIGN: Unblinded, before-after study. SETTING: Referral center for patients with heart failure. PATIENTS: Thirty patients with severe chronic heart failure and a left ventricular ejection fraction less than 40%. INTERVENTIONS: Invasive hemodynamic measurements were done (using a balloon-tipped thermodilution catheter) before and for 3 hours after a single oral dose of 50 mg of encainide. MEASUREMENTS AND MAIN RESULTS: Ninety to one hundred and twenty minutes after its administration, encainide produced a significant deterioration in cardiac performance, as reflected by a fall in cardiac index from 2.3 to 1.8 L/min.m2 body surface (mean change 0.5 +/- 0.1; P less than 0.001), a fall in stroke work index from 26 to 18 g.m/m2 (mean change 8 +/- 2; P less than 0.001), and an increase in left ventricular filling pressure from 19 to 22 mm Hg (mean change 3 +/- 2; P less than 0.05). These deleterious hemodynamic effects were accompanied by worsening symptoms of heart failure in 8 of the 30 patients. Serum levels of encainide and its metabolites, O-desmethylencainide and 3-methoxy-O-desmethylencainide, were within the therapeutic range in most patients. CONCLUSIONS: Encainide can cause adverse hemodynamic and clinical effects in patients with severe chronic heart failure. 相似文献
982.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved. 相似文献
983.
A 37-year-old woman receiving long-term hemodialysis was admitted to the hospital with a fever of unknown origin (6 weeks of unexplained, persistent, low-grade fever). Although she had received vancomycin hydrochloride 5 days before the onset of fever, the drug was not suspected as the cause because of the duration of fever, the administration of vancomycin on prior occasions without incident, and the lack of allergic stigmata. After hospitalization, vancomycin and gentamicin sulfate were administered empirically. Immediately thereafter, her temperature rose to 40 degrees C, and over the ensuing 24 hours, eosinophilia and a maculopapular rash developed that resolved entirely when antibiotic therapy was stopped and low-dose steroid therapy was instituted. The prolonged hypersensitivity reaction after a single dose of vancomycin is consistent with the greatly extended half-life of this drug in the population with end-stage renal disease and should alert physicians to the possibility of such persistent idiosyncratic reactions in this group. 相似文献
984.
Retrosternal dislocations of the clavicle have been reported previously in adults throughout the orthopedic literature. However, in children few cases have been noted in either the pediatric, emergency, or orthopedic literature. The potential for great vessel injury as well as acute airway compromise makes the retrosternal disruption of the sternoclavicular joint a surgical emergency that must be diagnosed quickly. Diagnosis is enhanced by the cephalic tilt view and by computed tomography (CT scan), as planar x-ray and tomography do not always reveal this potentially life-threatening condition. Surgical consultation must be sought acutely; however, management may need to begin prior to definitive repair. Emergency management begins by suspecting the injury, and with immediate airway and circulatory support for the patient. 相似文献
985.
T W Findley M G Stineman 《American journal of physical medicine & rehabilitation / Association of Academic Physiatrists》1989,68(5):240-251
The process of data entry and initial analysis to locate data errors is described. Basic terms are defined and a simple method of entering data by using word processing software is illustrated. Data checking is done by using visual check of the raw data. Statistical programs are then used to locate possible data errors by finding data points (outliers) that are very different from the average. Special graphic output of statistical programs, scatterplots and box and whisker plots can be used to further locate questionable data. Examples of data entry forms and annotated step by step data cleaning with the use of inexpensive programs for personal computers are presented. 相似文献
986.
987.
The activation of phospholipase A2 is believed to have an important role in the inflammatory process owing to its induction of eicosanoids, platelet activating factor, and other mediators. Soluble phospholipase A2 has been associated with exudates in different inflammatory conditions. In this review the general physiology and control of this enzyme and, in particular, the most recent findings on human synovial fluid phospholipase A2s are discussed. 相似文献
988.
A preliminary report of the short-term effect of carbonated beverage consumption on calcium metabolism in normal women 总被引:2,自引:0,他引:2
S Smith J Swain E M Brown G Wyshak T Albright V A Ravnikar I Schiff 《Archives of internal medicine》1989,149(11):2517-2519
A variety of nutritional factors influence the bioavailability of calcium and increase a woman's risk of osteoporosis. Eight healthy women completed an 8-week metabolic study designed to investigate the effect of nonalcoholic carbonated beverage consumption on calcium metabolism. Compared with women receiving a control diet, women consuming a diet high in nonalcoholic carbonated beverages demonstrated similar mean serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, parathyroid hormone, 1,25-dihydroxyvitamin D3, and osteocalcin. Twenty-four-hour urine volume, creatinine clearance, calcium-creatinine ratio, and phosphorus-creatinine ratio were similar during consumption of the diet high in nonalcoholic carbonated beverages and the control diet. Twenty-four-hour cyclic adenosine monophosphate-creatinine ratio was significantly lower in women consuming the diet high in nonalcoholic carbonated beverage compared with women receiving the control diet (342 +/- 27.4 nmol/mmol vs 409 +/- 22.1 nmol/mmol). Consumption of a diet high in nonalcoholic carbonated beverages on a short-term basis does not appear to affect adversely the serum or urinary markers of calcium metabolism. 相似文献
989.
990.
This study was conducted to test the effects of preadmission preparation on parent and child psychological upset at the time of tonsillectomy surgery, on child postsurgery behavior, and on parental compliance with home care instructions. Forty children aged 3 to 11 years who underwent tonsillectomy on an outpatient basis were studied. No significant differences were found in parent and child behaviors of those people in the preparation group compared with those in the nonpreparation group. Parental reports of home care revealed that the majority of parents did not follow at least one half of the physicians' home care instructions. The findings of the study indicate the need to further examine factors associated with parental compliance with home care instructions. 相似文献