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41.
Left ventricular outflow tract obstruction associated with chronic ventricular assist device support
Baradarian S Dembitsky WP Jaski B Abolhoda A Adamson R Chillcot S Daily PO 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(6):665-667
Favorable long-term patient outcome after insertion of a left ventricular assist device (LVAD) as a bridge to recovery or destination therapy for the treatment of end-stage cardiomyopathy is adversely affected by pathophysiologic changes affecting the heart. Alterations in the native aortic valve apparatus, specifically aortic valve cusp fusion, is an example of such a phenomenon and may especially affect patients in cases of bridge to recovery, a rare but reported event. A retrospective review of the last 33 LVAD placements at our institution was conducted, including reviews of operative reports and pathologic examinations of the native hearts. Seven hearts were found to have varying degrees of aortic valve cusp fusion after chronic LVAD support (63-1, 339 days). Five of these patients had native aortic valves, and two had bioprosthetic valves. The left ventricular outflow tracts in two patients were surgically occluded at the time of LVAD insertion. Aortic valve cusp fusion occurs in roughly 25% of patients on chronic LVAD support. This phenomenon may prove to be clinically significant by creating a potential source of emboli and infection. In addition, in the case of myocardial recovery, left ventricular outflow tract obstruction could limit parallel flow and produce suprasystemic ventricular pressures that in turn would elevate left ventricular end diastolic pressures. The latter may contribute to further myocardial injury, ultimately limiting the ability of an otherwise recovered heart to be weaned from LVAD support. 相似文献
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Tarnowski Kenneth J.; Gavaghan Mary Pat; Wisniewski Jack J. 《Journal of pediatric psychology》1989,14(3):463-472
Examined the effects of pain symptom severity and patient diagnosticstatus on pediatric staffs' acceptability ratings of 6 interventionsused to treat pediatric pain. Results indicated that (a) extinctionwas significantly less acceptable than all other behavioraland pharmacologic interventions, (b) self-management was moreacceptable than all other interventions with the exception ofcontingency management, (c) accelerative procedures and self-managementinterventions were preferred to pharmacologic treatment, (d)patient diagnostic status and pain symptom severity failed tosignificantly influence treatment ratings, (e) self-managementwas the only intervention differentially rated as a functionof pain symptom severity, and (f) pharmacologic treatment wasdifferentially rated as a function of patient diagnostic status. 相似文献
44.
Extrapelvic colon--areas of failure in a reoperation series: implications for adjuvant therapy 总被引:5,自引:0,他引:5
L L Gunderson H Sosin S Levitt 《International journal of radiation oncology, biology, physics》1985,11(4):731-741
A total of 230 patients had planned single or multiple reoperative procedures following "curative" resection of colorectal cancer at the University of Minnesota. The site of the primary lesion was extrapelvic in 91, and later evidence of cancer was found in 58 patients (64%) at re-operation and/or other follow-up. Eight of the 58 (14%) were converted to disease-free status. Incidence and patterns of failure were correlated with initial operative-pathologic extent of disease (87 of the 91 at risk had initial tumor extension beyond the bowel wall, involved nodes or both) and comparisons were made with the previously analyzed rectal reoperation patients. While a component of local-regional failure was more common with rectal lesions (48/74 at risk, 65%), it was not uncommon with extrapelvic primaries (44/91-48%). The incidence of hematogenous metastasis (DM) was equal, but the pattern of initial DM differed (extrapelvic colon--primarily liver; rectum--liver and lung). Peritoneal seeding was a more common component of failure with the extrapelvic primaries (19/91--21% vs 3/74-4%). Since surgery alone is inadequate treatment for many patients with colon as well as rectal cancer, the rationale of adjuvant radiation and systemic therapy, alone or in combination, is discussed. 相似文献
45.
Impromptu micturitional flow parameters in normal boys 总被引:1,自引:0,他引:1
Nonintrusive measurement of the hydrodynamic properties of the urinary stream (uroflowmetry) has been included in many adult urological evaluations as an objective diagnostic tool. Measurement and behavioral problems interfere with practical applications in children. We describe a standard procedure for obtaining "impromptu" micturitional flow parameters in clinical pediatric practice. Statistical correlations of these flow parameters in an unselected group of 142 normal boys between 2 and 12 years old are presented. Useful linear regression equations were derived from the sample to assist the clinician in predicting deviations from normal values. Limitations of the methodology are noted. 相似文献
46.
This randomized crossover study compared the pharmacokinetics of choline magnesium trisalicylate tablets administered once daily (3000 mg of salicylate) or twice daily (1500 mg of salicylate) for six d. Serum salicylate levels were measured by HPLC. Mean "trough" concentrations fell within the therapeutic range (5-30 mg/dL) with either regimen and were relatively constant, indicating that the steady state had been reached. The 24-h area under the salicylate curve (AUC0-24 h) after the final 3000-mg salicylate dose averaged about twice the mean 12-h AUC after the last 1500-mg dose, indicating that the two dosing regimens were equally bioavailable. Clinical observations and results of laboratory safety studies indicate that both dosage schedules of the drug are well tolerated. The present findings support the once-daily therapeutic use of choline magnesium trisalicylate. 相似文献
47.
D A Savaiano A AbouElAnouar D E Smith M D Levitt 《The American journal of clinical nutrition》1984,40(6):1219-1223
The use of fermented dairy foods is common in areas of the world where lactase deficiency is prevalent. Recently, we have shown that the digestion of lactose from yogurt is enhanced as compared to that from milk. This enhanced digestion is apparently due to inherent B-galactosidase in yogurt which is active in the gastrointestinal tract after consumption of the yogurt. Furthermore, yogurt is well tolerated by lactase-deficient subjects resulting in little or no gastrointestinal distress. Since other fermented and microbial-containing dairy foods are consumed worldwide and may also contain some "lactase" activity, we chose to evaluate the digestion of lactose from three of these products: pasteurized yogurt, cultured milk (buttermilk), and sweet acidophilus milk. Breath hydrogen techniques were used to evaluate lactose malabsorption in nine lactase-deficient subjects. The studies demonstrated that yogurt is unique among the products tested in enhancing the digestion of lactose. Furthermore, pasteurization of yogurt eliminated the enhanced digestion of lactose, reduced the inherent lactase activity of the yogurt by 10-fold and reduced cell counts by 100-fold. Interestingly, eight of nine subjects fed cultured milk experienced gastrointestinal distress, whereas all subjects fed pasteurized yogurt were symptom free, even though the amount of malabsorbed lactose was similar. 相似文献
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E E Levitt E L Baker R C Fish 《The American journal of clinical hypnosis》1990,32(4):225-36; discussion 237-49
Five experimental approaches to the resolution of the century-old Bernheim/Janet dispute and the issue of involuntariness or coercion (the classical suggestion effect) are presented. Four experiments are reported that follow one of the approaches: attempts to induce hypnotic subjects to resist suggestions made in trance. The design is one in which a "resistance instructor" proposes a reward for the resisting subject. Tentative inferences from the results are that the classical suggestion effect is found with a small number of subjects; for a larger number of subjects there is no classical suggestion effect, and for many subjects the outcome is equivocal. Relational factors in the hypnotic dyad influence responsiveness in the subject, the effect being least for those whose susceptibility is high. 相似文献