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81.
Takahisa Okano Matthew D. Horton Gary G. Fermanis David A. Horton 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):437-439
We report a re-do case of severe aortic valve stenosis due to pannus formation 29 years after an aortic Starr-Edwards caged-ball
valve implantation. A huge shelf of calcified and thick pannus tissue below the valve had reduced the already small orifice
by at least a third in surface area. The explanted Starr-Edwards valve revealed no mechanical or structural failure. Early
detection and treatment of pannus outgrowth is essential in order to prevent life-threatening prosthetic valve malfunctions. 相似文献
82.
83.
T Matthew Shields Charles H Hennekens 《Endocrinology & Metabolism Clinics of North America》2004,33(3):577-93, vii
Cardiovascular disease (CVD), which includes myocardial infarction(MI), stroke, and peripheral vascular disease, remains the leading cause of death in the United States and in most developed countries. In the United States today, 25% of patients have metabolic syndrome-including those who have had a prior occlusive vascular disease event, those who are having an acute MI or ischemic stroke, and finally, the largest segment of the population,namely those who have not yet experienced a clinical CVD, but whose risks are substantial (10-year risk 10%). This article reviews the totality of evidence for aspirin in the treatment and prevention of CVD and emphasizes its importance as adjunctive therapy for patients with metabolic syndrome. 相似文献
84.
Resuscitation training for medical students and junior doctors in the United Kingdom and United States was compared using questionnaires sent to medical schools in both countries. A marked deficiency in the provision of cardiopulmonary resuscitation training has been demonstrated in the United Kingdom; however, in the United States, the availability of uniform certifiable teaching is now widespread. Suggestions for the improvement of training in the United Kingdom are expected to increase medical student proficiency in cardiopulmonary resuscitation. The need for training in basic and advanced resuscitation prior to graduation from medical school is stressed. 相似文献
85.
Alan M. Mellow Trey Sunderland Robert M. Cohen Brian A. Lawlor James L. Hill Paul A. Newhouse Martin R. Cohen Dennis L. Murphy 《Psychopharmacology》1989,98(3):403-407
Thyrotropin releasing hormone (TRH) was administered intravenously to ten patients with Alzheimer's Disease (AD) in a high-dose paradigm, thought to maximize central nervous system effects and potentially produce facilitation of cholinergic function, a known property of the neuropeptide. Acute effects of TRH on behavioral, cognitive and physiologic measures were assessed after patients received 0.1 mg/kg TRH, 0.3 mg/kg TRH and placebo, the higher TRH dose and placebo being given in a randomized, double-blind fashion. Patients showed statistically significant increases in arousal and improvement in affect, as well as a modest improvement in semantic memory, all after receiving the higher TRH dose. Both TRH doses produced transient rises in systolic blood pressure, with no effect on diastolic blood pressure, heart rate or temperature. This study suggests that high-dose TRH can be safely administered to AD patients and is neurobehaviorally active; further studies are needed to determine the extent and mechanism of the cognitive and psychobiological properties of this peptide in AD and other neuropsychiatric disorders. 相似文献
86.
Regulation of G proteins by chronic antidepressant drug treatment in rat brain: tricyclics but not clorgyline increase Go alpha subunits. 总被引:4,自引:0,他引:4
K P Lesch C S Aulakh T J Tolliver J L Hill D L Murphy 《European journal of pharmacology》1991,207(4):361-364
The effect of long-term (3-week) administration of various antidepressant drugs on the steady-state concentrations of G protein alpha subunits, Gs alpha, Gi alpha, and Go alpha, has been investigated in rat brain using an enzyme-linked immunosorbent assay. Tricyclic antidepressants and clorgyline decreased Gs alpha and, to a lesser extent, Gi alpha in several brain regions, while Go alpha was increased by tricyclics but not clorgyline. We conclude that long-term treatment with antidepressant drugs exerts differential effects on G protein alpha subunits, and that antidepressant efficacy may potentially be based on functional modifications of signal transduction. 相似文献
87.
88.
Does atopy have any predictive value for laboratory animal allergy? A comparison of different concepts of atopy 总被引:2,自引:0,他引:2
Atopy is widely used as a discriminant in selection for employment involving exposure to allergenic substances. The validity of this has been tested in a population with a known burden of what is largely considered to be an IgE mediated disease, laboratory animal allergy. The findings suggest that atopy is insufficiently sensitive and specific for this purpose and that this is probably true for other occupational allergic diseases. The relation between different concepts of atopy--namely, atopy defined by family history, by personal history, and by skin prick tests with common allergens--has also been examined. The subpopulations identified by these criteria differed appreciably. Different concepts of atopy should not be used synonymously as they often are at present. 相似文献
89.
OBJECTIVE: Screening colonoscopy has been shown to reduce mortality and cancer stage in hereditary nonpolyposis colorectal cancer (HNPCC) individuals. However, the benefit of screening in intermediate risk groups is unknown. The most recent national guidelines have recommended a reduction of screening frequency for the intermediate risk group. Therefore, this study aims to compare the results of colonoscopic screening in HNPCC and intermediate risk groups and assess the effect of the most recent screening protocol recommendations. METHOD: A total of 244 individuals; 108 from HNPCC families (28 mismatch repair gene carriers) and 136 from intermediate risk families were referred for regular colonoscopic screening by the Regional Genetics Service. Findings from 417 colonoscopies performed between 1992 and 2003 were evaluated. RESULTS: A total of three cancers, 39 adenomas and 41 hyperplastic polyps were found in the HNPCC group compared with one cancer, 22 adenomas and 19 hyperplasic polyps in the intermediate risk group. If the recent screening guidelines for the intermediate group were applied, then 89 (44%) fewer colonoscopies would have been performed. Although no cancers would have been missed, six adenomas (mean size = 5.7 mm, range 2-10 mm) with two graded as severely dysplasic and six hyperplastic polyps would not have been detected. CONCLUSION: The detection rate and distribution of adenomas were similar in both groups. If the new colonoscopic screening recommendations for the intermediate risk group had been applied, a small number of significant lesions would have been missed. 相似文献
90.