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991.
Mafee MF; Peyman GA; Grisolano JE; Fletcher ME; Spigos DG; Wehrli FW; Rasouli F; Capek V 《Radiology》1986,160(3):773-780
Twenty-one patients with intraocular disease were studied by magnetic resonance (MR) imaging and computed tomography (CT). In 13 cases, malignant uveal melanoma was considered the likely diagnosis. Both imaging methods were accurate in determining the location and size of uveal melanomas. MR imaging was superior for the assessment of possible associated retinal detachment, for assessment of vitreous change, and for differentiating uveal melanoma from choroidal hemangioma and choroidal detachment. A case of retinal gliosis could not be differentiated from uveal melanoma by either technique. Uveal melanomas appeared as hyperintense lesions on T1-weighted images and as hypointense lesions on T2-weighted images. High signal intensity of the vitreous was observed in patients with vitritis and in those who were thought to have protein leaking into the vitreous as a result of impairment of the retinal-blood barrier. 相似文献
992.
Spontaneous rupture of the spleen in pregnancy is rare. It presents with severe internal haemorrhage with a high perinatal and maternal mortality. Splenic preservation is now a well-known option in dealing with splenic damage, and is recommended where possible to avoid diminished immunological competence. This is the first reported case of splenic preservation following splenic damage in pregnancy. 相似文献
993.
994.
P. J. Fletcher 《Psychopharmacology》1987,93(4):498-501
The hypothesis that systemically administered 5-hydroxytryptamine (5-HT) reduces feeding by a specific action on satiation and satiety processes was examined using a food-rewarded runway task. Over the course of 15 successive trials, with food available for 2 min on each trial, the development of satiation was monitored following treatment with 5-HT (1 and 2 mg/kg SC) and saline. The 5-HT failed to alter runway performance over the early trials, but then induced marked decrements in running speed and food intake. Analysis of cumulative food intake curves showed that 5-HT significantly reduced food intake beginning at the point where a decline in the rate of feeding was observed under control conditions. These results indicate that 5-HT exerts its anorectic effect only after some food has been ingested, and support the hypothesis that 5-HT accelerates the development of satiation and satiety. 相似文献
995.
996.
Colleen F. Sintek M.D. Thomas A. Pfeffer M.D. Gary S. Kochamba M.D. Kwok L. Yun M.D. Alden D. Fletcher M.D. Siavosh Khonsari M.D. 《Journal of cardiac surgery》1998,13(5):360-368
BACKGROUND: Many studies have demonstrated the superior hemodynamics of stentless porcine aortic valves compared to stented valves. This article describes the operative techniques and reviews our 5-year experience with the Medtronic Freestyle stentless valve. METHODS: Between January 1993 and November 1997, 95 patients underwent implantation of the Medtronic Freestyle valve at a mean age of 76 years. All patients were seen at 6 months, 1 year, and annually thereafter for clinical assessment and Doppler echocardiography. RESULTS: There were three operative and ten late deaths (two cardiac and eight noncardiac). Three strokes and four transient ischemic attacks occurred in the follow-up period. Four patients had bacteremia that was treated successfully with antibiotics. No patient required reoperation for valve-related problems. Serial echocardiograms revealed a decrease in mean systolic gradients across the valve during the first year and an increase in effective orifice areas. Ninety-one percent of patients had no, or trace, aortic insufficiency at the time of discharge and this has not increased over time. CONCLUSION: The Medtronic Freestyle valve has excellent hemodynamics and good clinical results. In our experience, no patient has required reoperation in a 5-year follow-up. 相似文献
997.
Donna Fletcher 《Journal of developmental and physical disabilities》1996,8(2):151-165
Research is reviewed concerning illegal parking in spaces reserved for people with disabilities. The problem of the high frequency of illegal parking has been well documented. Methods for decreasing frequency of violations that have been investigated include types of signs, messages on signs, printed messages left on windshields, patrols by volunteers, fines, and increased enforcement by police. Vertical signs, particularly signs warning of serious financial consequences for illegal parking, decrease the violation rate, but low enforcement rate remains a problem. Demographics of violators and possible reasons for their illegal parking are presented. 相似文献
998.
Atypical fibrous histiocytoma of the skin: clinicopathologic analysis of 59 cases with evidence of infrequent metastasis. 总被引:3,自引:0,他引:3
Steven Kaddu Máirín E McMenamin Christopher D M Fletcher 《The American journal of surgical pathology》2002,26(1):35-46
Atypical fibrous histiocytoma is an uncommon, poorly documented variant of cutaneous fibrous histiocytoma. We studied 59 cases of atypical fibrous histiocytoma to better characterize the clinicopathologic spectrum. There were 33 males and 26 females (median age 38 years; range 5-79 years) with solitary lesions arising on lower (25 cases) and upper (17 cases) extremities, trunk (6 cases), head and neck (4 cases), and vulva (1 case); anatomic location was not stated in six cases. Lesions measured 0.4-8 cm in diameter (median 1.5 cm) and clinically were nodules (40 cases), polypoid tumors (18 cases), or a slightly elevated plaque (1 case). Histologically, the lesions were primarily dermal with superficial involvement of the subcutis in one third of the cases. Salient features included a proliferation of pleomorphic, plump, spindle, and/or polyhedral cells with mainly large, hyperchromatic, irregular, or bizarre nuclei, set in a background of classic features of fibrous histiocytoma, including spindle cell areas showing a storiform pattern and entrapped thickened, hyaline collagen bundles, especially at the periphery. Multinucleated giant cells, often with bizarre nuclei and foamy, sometimes hemosiderin-rich, cytoplasm were also variably present. The degree of pleomorphism varied from only focal and minimal (14 cases) or moderate (24 cases) to marked (21 cases). Mitotic activity was observed in 55 lesions, and the number of mitotic figures ranged from 1 to 15 per 10 high power fields. Atypical mitoses were noted in 20 lesions. Furthermore, some cases of atypical fibrous histiocytoma displayed other worrisome features less often observed in ordinary FH, including unusually large size (diameter >2 cm, 8 cases), involvement of the superficial subcutis (19 cases), and geographic necrosis (7 cases). Immunohistochemical studies performed in 42 cases showed only focal smooth muscle actin (10 cases) and CD34 (4 cases) positivity, whereas CD68, S-100 protein, desmin, pan-keratin, and epithelial membrane antigen were negative. Clinical follow-up data available in 21 patients (mean duration of follow-up 50.6 months, median 43 months) revealed local recurrences in three patients (one repeated); two patients developed distant metastases, one of whom died after 96 months. These two cases were not histologically distinct from the group as a whole. We conclude that atypical fibrous histiocytoma has a broader clinicopathologic spectrum than previously realized. Lesions with floridly atypical features represent potential pitfalls for overinterpretation as pleomorphic sarcoma, which would appear to be inappropriate in most cases. Provided that atypical fibrous histiocytoma is treated by complete excision, a benign outcome is to be expected in most cases. However, similar to the cellular and aneurysmal variants of fibrous histiocytoma, atypical fibrous histiocytoma shows a higher tendency to recur locally than ordinary fibrous histiocytoma and may rarely metastasize. 相似文献
999.
1000.
Weekly fasting serum calcitonin levels and biochemical indices of bone metabolism were measured in 13 postmenopausal women being given hormone replacement therapy over a period of 8 weeks. All of the biochemical indices except urinary hydroxyproline creatinine ratios fell significantly, indicating that the treatments were effective in reducing bone turnover. Calcitonin levels fell significantly and, within the individual, levels were positively correlated with adjusted calcium levels. These findings do not support the theory that estrogen conserves bone by stimulating calcitonin secretion. 相似文献