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Young striped bass (Morone saxatilis) with uninflated gas bladders were less sensitive to selenate and more sensitive to selenite exposure than normally developing striped bass in 96-hour acute toxicity tests. Gas bladder inflation failure is a common problem in the culture of striped bass and some other species, and care should be taken to avoid the use of fish with uninflated gas bladders in research.  相似文献   
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BACKGROUND: Transplantation for patients with a high pulmonary vascular resistance (PVR) carries an increased risk of mortality and right heart failure following heart transplantation and continues to be a major problem. We evaluated the use of hearts from patients who underwent heart and lung transplantation for primary pulmonary hypertension (PPH) as part of a domino procedure because these hearts have hypertrophied right ventricles used to increased pulmonary pressures, but could have a compromised left ventricle or irreversible damage of the right ventricle. METHODS: We reviewed 12 patients with PVR >4 Wood units who underwent orthotopic heart transplantation between 1989 and 1998 using hearts from donors with PPH as part of a domino procedure. RESULTS: We studied 10 men and 2 women, mean age 42.9 years. Mean PVR was 5.3 (range, 4-9) Wood units. Mean ischemia time was 85.3 minutes, and mean donor age was 32 years. Actuarial survival was 75% at 1 year and 75% at 5 years. In the early post-operative period, 3 patients had temporary arrhythmias, 2 required permanent pacemaker implantation, 1 had atrial fibrillation, and 1 had ventricular tachycardia that required defibrillator implantation. At a mean follow-up of 7.8 years, 2 patients had developed asymptomatic transplant coronary disease (both at 8.5 years after transplantation), 1 moderate and 1 very mild; the rest had none. Mean left ventricular ejection fraction at latest follow-up was 70.1% (range, 63%-78%). Right ventricular function assessed clinically and by echocardiography was adequate in the short and long term. CONCLUSIONS: Our results suggest that heart and lung recipients with PPH can provide useful donor hearts to patients with increased PVR and that these hearts function well in the intermediate and long term.  相似文献   
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Twenty-nine females with metastatic or locally recurrent carcinoma of the breast were treated orally with 1 g of medroxyprogesterone acetate (MPA) daily. This was used as a second- or third-line treatment. Serum concentration of MPA was measured over a 28-day period. We have demonstrated a significantly greater area-under-the-concentration-time curve, peak, and steady-state MPA concentration for Provera at 100- and 200-mg tablets (Upjohn) than for Farlutal at 500-mg tablets (Farmitalia). Relative bioavailability of preparations should be considered when prescribing or assessing treatment results when MPA is used.  相似文献   
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We measured serum alkaline phosphatase isoenzymes and osteocalcin levels in 40 healthy women at 4-week intervals throughout uncomplicated pregnancies and 6 weeks after delivery in 17 women. Serum bone alkaline phosphatase was significantly higher in the third trimester than in early pregnancy (P less than 0.001), and this elevation was still apparent at the end of the puerperium, suggesting increased bone turnover. Serum osteocalcin was not detected (less than 0.2 micrograms/L) after the first trimester in the majority of women, and it reappeared within 48 h after delivery. The disappearance of osteocalcin after the first trimester and its rapid reappearance after delivery suggest placental clearance of this peptide. We conclude that serum osteocalcin measurements cannot be used as a marker of bone metabolism during pregnancy.  相似文献   
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A mobility protocol for critically ill adults.   总被引:1,自引:0,他引:1  
Although the complications of immobility are well-described in the literature, critically ill patients are often subjected to prolonged periods of bed rest. Nurses, by virtue of their expertise in preventing iatrogenic complications, are in an ideal position to prevent the adverse outcomes associated with immobility. This article describes how nurses can use a mobility protocol to increase the activity of critically ill patients in a timely manner that may prevent the infirmity and suffering that is caused by unnecessarily long periods of bed rest.  相似文献   
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