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31.
J D Waldman F J Schoen S E Kirkpatrick J W Mathewson L George J J Lamberti 《Circulation》1987,76(1):109-114
Balloon dilatation (BD) of bioprosthetic valves was investigated in vivo and in vitro. Four children with stenotic bioprosthetic porcine valves in the pulmonary position underwent BD of the valve 10 to 24 months after its insertion. Average valve gradient was reduced from 47.5 to 27 mm Hg. Obstruction at the conduit-branch pulmonary artery connection became apparent after dilatation of the valve. These distal stenoses were also dilated. BD technique was tested in vitro with the use of nonstenotic valves in fresh conduits. No damage to the valve or to the conduit was found when oversized balloons were used in a standard fashion or intentionally inflated until rupture. It is concluded that conduit replacement may be deferred by balloon dilatation of obstructed biological valves and/or a stenotic conduit-pulmonary artery anastomosis. 相似文献
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Kaplan RC Heckbert SR Koepsell TD Furberg CD Polak JF Schoen RE Psaty BM 《Journal of the American Geriatrics Society》2001,49(2):126-133
OBJECTIVES: We sought to estimate the incidence of hospitalization for upper and lower gastrointestinal bleeding among older persons and to identify independent risk factors. DESIGN: Prospective cohort study. SETTING: The Cardiovascular Health Study (CHS). PARTICIPANTS: 5,888 noninstitutionalized men and women age 65 years or older in four U.S. communities enrolled in the CHS. MEASUREMENTS: Gastrointestinal bleeding events during the period 1989 through 1998 were identified using hospital discharge diagnosis codes and confirmed by medical records review. Risk-factor information was collected in a standardized fashion at study baseline and annually during follow-up. RESULTS: Among CHS participants (mean baseline age 73.3 years, 42% male), the incidence of hospitalized gastrointestinal bleeding was 6.8/1,000 person-years. In multivariate analyses, advanced age, male sex, unmarried status, cardiovascular disease, difficulty with daily activities, use of multiple medications, and use of oral anticoagulants were independent risk factors. Compared with nonsmokers, subjects who smoked more than half a pack per day had a multivariate-adjusted hazard ratio (HR) of 2.14 (95% confidence interval [CI] = 1.22-3.75) for upper gastrointestinal bleeding and a multivariate-adjusted HR of 0.21 (95% CI = 0.03-1.54) for lower gastrointestinal bleeding. Aspirin users did not have an elevated risk of upper gastrointestinal bleeding (HR = 0.76, 95% CI = 0.52-1.11), and users of other nonsteroidal anti-inflammatory drugs had a HR of 1.54 (95 % CI = 0.99-2.36). Low ankle-arm systolic blood pressure index was associated with higher risk of gastrointestinal bleeding among subjects with clinical cardiovascular disease but not among those without clinical cardiovascular disease. CONCLUSION: This study identifies risk factors for gastrointestinal bleeding, such as disability, that may be amenable to modification. The findings will help clinicians to identify older persons who are at high risk for gastrointestinal bleeding. 相似文献
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Peptic ulcer and bleeding events associated with rofecoxib in a 3-year colorectal adenoma chemoprevention trial 总被引:5,自引:0,他引:5
Lanas A Baron JA Sandler RS Horgan K Bolognese J Oxenius B Quan H Watson D Cook TJ Schoen R Burke C Loftus S Niv Y Ridell R Morton D Bresalier R 《Gastroenterology》2007,132(2):490-497
BACKGROUND & AIMS: Our aim was to establish the incidence of symptomatic upper gastrointestinal ulcers, ulcer perforation, ulcer obstruction, or bleeding episodes (PUBs) associated with the use of selective cyclooxygenase-2 inhibitors at standard clinical doses compared with placebo. We report here on the PUB outcomes associated with the use of rofecoxib 25 mg in a 3-year, multicenter, double-blind, placebo-controlled trial designed to determine the effect of rofecoxib on the risk of recurrent neoplastic polyps of the colon. METHODS: A total of 2587 patients with a history of colorectal adenomas underwent randomization to 25 mg/day of rofecoxib or to placebo. Investigator-reported PUBs were adjudicated by an external blinded committee. Kaplan-Meier and Cox proportional hazards techniques were used to estimate incidence and relative risks of PUBs in an intention-to-treat analysis. RESULTS: Patients assigned to rofecoxib had a higher incidence of confirmed PUBs than those randomized to placebo (.88 vs .18 events per 100 patient-years; relative risk, 4.9; 95% confidence interval, 1.98-14.54). The incidence of confirmed complicated PUBs (ulcer perforation, obstruction, or bleeds) was low, but was numerically higher in the rofecoxib than in the placebo group (.23 vs .06 events per 100 patient-years; relative risk, 3.8; 95% confidence interval, .72-37.46; P = .14). Rofecoxib increased the incidence of confirmed PUBs vs placebo in both low-dose aspirin users and nonusers. CONCLUSIONS: Among patients with a history of colorectal adenomas, the long-term use of 25 mg/day of rofecoxib was associated with an increased risk of clinically relevant upper gastrointestinal events when compared with placebo. 相似文献
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Journal of Molecular Medicine - Die Erfahrungen über die Behandlung von Leukämien, insbesondere ohronischer Myelosen mit Urethan werden als Grundlage zu Betrachtungen über seine... 相似文献