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Nineteen eyes on which pars plana vitrectomy was performed were studied with fluorescein angiography. The degree of background diabetic retinopathy before and after surgical treatment appeared unchanged. The degree of proliferative retinopathy not only was less after surgical treatment, but continued to show regression with time. 相似文献
24.
BACKGROUND: Little is known about the effect of passing time on risk of resection among patients with complete small bowel obstruction. We sought to provide a benchmark of the relationship of time from symptom onset to surgical treatment on the need for resection in patients with complete small bowel obstruction. STUDY DESIGN: We performed an observational study of patients with surgically treated complete small bowel obstruction at an inner-city urban tertiary referral center and a municipal hospital. Patients were sampled randomly retrospectively (n=60), and prospectively (n=81), for a final sample of 141. Detailed clinical and time data were abstracted from medical records including out-of-hospital examinations. Risk of resection was calculated using actuarial life table methods. Linear regression was used to determine factors affecting time to treatment. RESULTS: All patients were treated surgically for obstruction; 45% underwent resection. Resected patients had longer (11 days versus 8 days; p=0.01) and more complicated (31% versus 14% in ICU; p=0.01) hospital stays. The risk of resection was 4% among patients with 24 hours of unresponsive symptoms; it increased to 10% to 14% through 96 hours, then dropped slightly but did not disappear. Patients treated first with a tube had longer times between first examination and operation, system-time (40.6 hours versus 10.2 hours; p=0.0007), but this was not associated with an increased resection risk. System-times were shorter among patients seen first in the emergency department (median: 25.7 hours versus 59.7 hours; p=0.0001). CONCLUSIONS: Physicians should be cautious in postponing surgery beyond 24 hours in patients with unresponsive symptoms from complete obstruction. The risk of resection rises dramatically, remains elevated through 96 hours of unresolved symptoms, then declines but does not disappear. 相似文献
25.
The epidemic of obesity in the United States has spread at such an alarming rate over the last decade that most adults are now overweight or obese. The association of obesity with mortality and a broad range of significant medical comorbidities portends staggering healthcare, social, and economic costs. Treatment should be directed at the fundamental imbalance between energy intake and expenditure in the context of an environment that increasingly favors excess weight. Therefore, treatment plans need to address the multiple factors that contribute to obesity, including high-calorie diets, sedentary lifestyles, and weight-sustaining behaviors. Primary care physicians would do well to focus on helping willing patients make small changes motivated more by health promotion and fitness than by weight loss. 相似文献
26.
Kerfoot BP Baker H Volkan K Church PA Federman DD Masser BA DeWOLF WC 《The Journal of urology》2004,172(1):282-285
PURPOSE: To date published efforts to assess and improve medical student learning in urology have been limited due to the lack of an assessment tool with which to measure student learning. We report the development of a validated measure of medical student learning in urology. MATERIALS AND METHODS: Four core topics in clinical urology were selected as the focus of the test development, namely prostate cancer, screening with prostate specific antigen, benign prostatic hyperplasia and erectile dysfunction. Detailed curricula and multiple choice questions were created for each topic. Content validity of the curriculum and 28 item examination was established by a panel of 2 urologists and 2 medical physicians. Instrument reliability was determined by administering the test on line to third-year surgery students. Test construct validity was established through its administration to 19 urology residents and attending physicians. RESULTS: Reliability of the 28-item test instrument was measured by Cronbach's alpha at 0.76 and its 1-week test-retest reliability was 0.72. All urology experts performed well on the test. Mean urological expert scores were significantly higher than mean student post-test scores (24.9 +/- 2.1 vs 17.8 +/- 3.8, 2-tailed t test p <0.001). Urological experts with greater urological training had higher scores than those with less residency training. CONCLUSIONS: This study documents the development of a validated measure of medical student learning in urology. This validated instrument has the potential to improve educational quality control at medical schools and facilitate the development of effective, evidence based teaching methods. 相似文献
27.
Federman DD 《Sleep》2003,26(3):333-336
STUDY OBJECTIVES: Sleep and circadian rhythms are biologic processes operative in health and disease, but as yet there is no articulated curriculum for undergraduate medical education. DESIGN: A multidisciplinary expert-opinion approach was utilized to assess and define education objectives and the potential for implementation. SETTING: N/A. PATIENTS OR PARTICIPANTS: National Institutes of Health Sleep Academic Awardees. INTERVENTIONS: N/A. RESULTS: Four competencies with examples of instruction objectives were identified relating to sleep processes and sleep need, the impact of sleep and sleep disorders on human illness, the sleep history, and the application of sleep physiology and pathophysiology to patent care. Various strategies and tools are currently available for implementation and assessment of learning objectives for these knowledge and skills. CONCLUSION: The core competencies can be designed to improve physician knowledge and skills in recognizing and intervening in sleep problems and disorders. Learning objectives can be immediately incorporated into most medical school curricula. At the same time, these competencies serve as an important bridge across multiple medical content areas and disciplines and between undergraduate and postgraduate training. 相似文献
28.
Age-related macular degeneration (AMD) remains the leading cause of visual loss in adults older than 65 years. Retinal angiomatous proliferation (RAP) is a newly recognized manifestation of exudative AMD that has a poor natural history and demonstrated resistance to treatment with conventional laser photocoagulation. A novel surgical technique has been developed in this pilot series that shows promise in the treatment of this subtype of neovascular lesions. Through specific surgical lysis of the feeding arteriole and draining venule of an RAP lesion, improvement in visual acuity has been noted. This has been correlated with resolution of intraretinal edema and flattening of associated pigment epithelial detachment, which was confirmed by fluorescein angiography, optical coherence tomography, and high-speed indocyanine green angiography. 相似文献
29.
Lipton JM Federman N Khabbaze Y Schwartz CL Hilliard LM Clark JI Vlachos A;Diamond-Black Anemia Registry 《Journal of pediatric hematology/oncology》2001,23(1):39-44
PURPOSE: Diamond-Blackfan anemia (DBA) is a congenital pure red cell aplasia, usually presenting in infancy or early childhood. A review of the literature strongly supports a predisposition to hematopoietic malignancy. Recently, solid tumors have been reported, some attributable to hemosiderosis and/or androgen therapy. Two cases of osteogenic sarcoma have also been documented. An analysis from the Diamond-Blackfan Anemia Registry was performed to evaluate the cancer risk in patients with DBA. METHODS: The Diamond-Blackfan Anemia Registry of North America (DBAR) is a comprehensive database of patients with DBA enrolled, after informed consent, through outreach to pediatric hematologists and family groups. The patients and/or their families complete a detailed questionnaire, and a review of medical records and telephone interviews are performed to complete and clarify the information provided. RESULTS: Of the 354 patients registered in the DBAR, there were six patients meeting the accepted diagnostic criteria for DBA who were found to have malignancies. Three patients had osteogenic sarcoma diagnosed, one with myelodysplastic syndrome, one with colon carcinoma, and one with a soft tissue sarcoma. CONCLUSION: There appears to be an association of osteogenic sarcoma with DBA. A young age at presentation may be a feature of DBA-associated osteogenic sarcoma. Because of the immaturity of the database, the actuarial risk for osteogenic sarcoma and other cancers in individuals with DBA cannot be ascertained. Speculation is made regarding the nature of the molecular defect leading to the association of DBA and osteogenic sarcoma. 相似文献
30.
Benz EB Federman M Godleski JJ Bierbaum BE Thornhill TS Spector M 《Biomaterials》2001,22(21):2835-2842
The objectives of this transmission electron microscopy study of peri-implant tissues retrieved at revision arthroplasty were to (1) determine the size distribution of intracellular polyethylene particles, and (2) assess the cellular response to phagocytosed polyethylene particles as revealed by the condition of the cellular organelles. The frequency distributions of intracellular polyethylene particle sizes for 15 cases of total hip replacement showed that more than 75% of the particles had lengths of less than 0.5 microm. More than 90% of the particles were less than 1.0 microm in size. In comparison, the frequency distribution for the particles in cellscomprising tissue retrieved from three total knee replacement prostheses showed that only 43% of the particles were less than 0.5 microm in length and 72% were less than 1 microm in size. There was no statistically significant difference in the mean particle length between the specimens from the hip and knee patients. The majority of the cells containing polyethylene were without signs of degeneration. The cytoplasmic and nuclear membranes were intact. Several electron lucent voids which once contained polyethylene particles were seen surrounded by several healthy appearing mitochondria, which displayed sharp membranes and intact cristae. There were no signs of a cytotoxic response to polyethylene at the ultrastructural level. 相似文献