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91.
Chemoprevention refers to suppression or reversal of the carcinogenic process using pharmacologic or nutritional agents. Colorectal carcinogenesis is a protracted, multistep process that offers opportunities for prevention. Aspirin and selective cyclooxygenase-2 inhibitors (coxibs) have been evaluated for the prevention of sporadic adenoma recurrence. Aspirin was shown to reduce adenoma recurrence rates in patients with prior colorectal neoplasms; however, the optimal dosage remains unclear. Recent studies of coxibs indicate that these agents are effective in reducing sporadic adenoma recurrence, but chronic use can result in serious cardiovascular toxicity. These data underscore the need for chemopreventive agents with acceptable risk-to-benefit ratios. In this regard, nitric-oxide-releasing aspirin shows chemopreventive efficacy in preclinical models and holds promise for reduced toxicity in humans. Furthermore, ongoing chemoprevention trials are evaluating nutritional supplements, such as folic acid and selenium, and results are eagerly awaited.  相似文献   
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BACKGROUND: Acute pain is common after cardiac surgery and can keep patients from participating in activities that prevent postoperative complications. Accurate assessment and understanding of pain are vital for providing satisfactory pain control and optimizing recovery. OBJECTIVES: To describe pain levels for 5 activities expected of patients after cardiac surgery on postoperative days 1 to 6 and changes in pain levels after chest tube removal and extubation. METHODS: Adults who underwent cardiac surgery were asked to rate the pain associated with various types of activities on postoperative days 1 to 6. Pain levels were compared by postoperative day, activity, and type of cardiac surgery. Pain scores before and after chest tube removal and extubation also were analyzed. RESULTS: Pain scores were higher on earlier postoperative days. The order of overall pain scores among activities (P < .01) from highest to lowest was coughing, moving or turning in bed, getting up, deep breathing or using the incentive spirometer, and resting. Changes in pain reported with coughing (P = .03) and deep breathing or using the incentive spirometer (P = .005) differed significantly over time between surgery groups. After chest tubes were discontinued, patients had lower pain levels at rest (P = .01), with coughing (P = .05), and when getting up (P = .03). CONCLUSIONS: Pain relief is an important outcome of care. A comprehensive, individualized assessment of pain that incorporates activity levels is necessary to promote satisfactory management of pain.  相似文献   
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BACKGROUND: Despite increasing numbers of morbidly obese patients admitted to acute care facilities for surgery or treatment of nonsurgical conditions, there is little evidence of the problems nurses face in providing care to these patients. Anecdotal evidence suggests that the care of these patients is more demanding than the care of nonobese patients. The objective of this study was to describe nurses' perceptions of the challenges that they face when caring for morbidly obese patients. METHODS: Focus groups of nurses from a tertiary care facility were convened. A trained facilitator posed questions to the group concerning various aspects of care for morbidly obese patients. Comments of respondents were categorized using NVIVO software. RESULTS: Nurses reported concerns about the increased staffing needs required for care of these patients and the particular challenges of the physical care. Concerns also included the availability, placement, and use of specialized equipment. Room size and the absence of some equipment were also problematic. Finally, nurses perceived safety issues, both for themselves and their patients. CONCLUSIONS: Morbidly obese patients in the acute care setting require specialized nursing care in terms of techniques, levels of staffing required, and the use of specialized equipment.  相似文献   
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Jaccoud arthropathy (JA), now most commonly associated with systemic lupus erythematosus (SLE), is widely perceived as a benign joint deformity that is radiographically nonerosive and that confers little if any disability. Advances and accessibility of imaging modalities such as ultrasound (US) are challenging the complacency in perceiving SLE-JA and SLE arthritis as benign processes. Prompted by a patient with SLE-JA in which joint erosion was detectable on US but not evident on radiograph, this review assesses the potential utility of US to guide management and promote understanding of SLE arthritis and its poorly understood pathogenesis.  相似文献   
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Background: Anesthesia is associated with complications, and some of them may be fatal. The authors investigated the circumstances under which deaths were associated with anesthesia. In Denmark, the specialty anesthesiology encompasses emergency medicine, chronic and acute pain medicine, anesthetic procedures, perioperative care medicine, and intensive care medicine.

Methods: The authors retrospectively investigated anesthesia related deaths registered by the Danish Patient Insurance Association.

Results: From 1996 to 2004, 27,971 claims were made by the Danish Patient Insurance Association covering all medical specialties, of which 1,256 files (4.5%) were related to anesthesia. In 24 cases, the patient's death was considered to result from the anesthetic procedure: 4 deaths were related to airway management, 2 to ventilation management, 4 to central venous catheter placement, 4 as a result of medication errors, 4 from infusion pump problems, and 4 after complications from regional blockades. Severe hemorrhage caused 1 death, and in 1 case the cause was uncertain.  相似文献   

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