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1.
A surgical technique was used to establish chronic intestinal ulcers in Sprague-Dawley rats. A 2-cm-long segment of the distal ileum was excised and left attached on the mesentery. The ileum was reanastomosed. The excluded ileal segment formed a 'cyst' of various sizes. Initially, the anastomoses healed well, but after 6-8 weeks para-anastomotic ulcers developed in more than 50% of the rats. Histopathology showed a chronic inflammatory reaction with a predominance of mononuclear cells and increased numbers of eosinophilic granulocytes. The surface of the ulcers was covered with bacteria. Penetrating ulcers with fistula formation occurred. It is concluded that this experimental model may be useful for time sequential studies of the development of chronic and ulcerative ileitis. It may also be used to study the effect of medical and surgical regimens for the treatment of non-specific chronic inflammatory bowel disease.  相似文献   
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Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies.  相似文献   
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Background: Pemetrexed and cisplatin have recently been shown to significantly improve survival compared with cisplatin alone. However, there are only limited data reflecting teaching hospital experience outside a clinical trial. Pemetrexed has only been available in Australia on a restricted basis since 2002. We reviewed our experience of patients treated on the Australian ‘Special Access Scheme’ at three major thoracic oncology units. Methods: Charts were reviewed for all patients enrolled on the scheme. Data was extracted on age, World Health Organization (WHO) performance status, histology, prior therapy, time from diagnosis to starting pemetrexed, chemotherapy (pemetrexed alone or with a platinum), cycle number, response rate, actuarial progression‐free and overall survival. Doses were cisplatin 75 mg/m2 or carboplatin AUC = 5 and pemetrexed 500 mg/m2 every 21 days. Results: 52 patients (32 male and 20 female) were reviewed. Median age was 58 years and 88% were WHO 0–1. Histology included 54% epithelial, 17% biphasic (epithelial and sarcomatoid) and 21% undefined. The median time from diagnosis to administration of pemetrexed was 145 days. Sixty‐five percent had minimal surgical intervention with video assisted thoracoscopy, pleurodesis and biopsy, while 19% had received prior palliative radiation. Seventy‐one percent were chemotherapy naïve, the remaining 29% having received previous platinum and/or gemcitabine regimens. Twenty‐three percent had pemetrexed alone, 35% in combination with carboplatin and 42% with cisplatin. The median number of cycles was 4 (range 1–13). The response rate was 33%. No toxicity was observed in 20% grade 3–4 toxicity in 10% (majority nausea/vomiting). The median progression‐free and overall survival times from starting pemetrexed were 184 days and 298 days, respectively. Conclusions: Pemetrexed‐based regimens are safe and effective in a community setting in malignant mesothelioma.  相似文献   
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Between 1969 and 1993, 123 patients were accepted in this unit for surgery for refractory hyperparathyroidism associated with chronic renal failure. Subtotal parathyroidectomy was the procedure of choice. At operation, four or more parathyroids were identified in 75% of patients. Methylene blue localised additional parathyroids in 32% of initial explorations in which it was used. Coincidental thyroid pathology was found in 8.3%, including papillary carcinoma in 2.4%. No further parathyroid surgery was required in 90% of patients at a mean of 6.6 years after operation. Reoperation (10%) was more likely to be required (14.3%) when less than four glands were found than when four or more were found (8.5%). Patients continuing on dialysis were more likely to need reoperation than those with functioning renal transplants.  相似文献   
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Topographic order in the rat retinocollicular projection emerges from an initially diffuse projection during an early postnatal remodeling period that is coincident with the period of naturally occurring ganglion cell death. Here, we examine the relationship between a retinal axon's position along the medial-lateral axis as it enters the superior colliculus (SC) and its ability to form an appropriately positioned arbor and survive the remodeling period. At E18-E19, prior to map remodeling, axons labeled with focal DiI injections in the periphery of temporal, nasal, superior or inferior retina are widespread along the medial-lateral SC axis. At P12, after remodeling, the distributions of axons remain widespread over the medial-lateral SC axis relative to the positioning of their terminal arborizations, and resemble the distributions labeled at E18-E19, with the exception that the small proportion of axons most widely mispositioned along the medial-lateral SC axis are less frequent. These data indicate that the most widely mispositioned retinal axons are preferentially eliminated, but that a high proportion of retinal axons mispositioned along the medial-lateral axis as they enter the SC can correct their position, form topographically appropriate arbors, and survive the remodeling period.  相似文献   
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