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Malignant melanoma of the mucous membranes is rare and has a very poor prognosis. When localized in the nose, the tumor becomes apparent late in the course of the disease with nasal obstruction and epistaxis. Distant metastases are uncommon, but any organ of the body can be involved. A case of a malignant melanoma of the nasal mucosa with metastasis to the small intestine is presented, and the natural history of the metastatic disease is discussed.  相似文献   
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To examine the relationship between gross hematuria and sickle cell disorders, all patients admitted to Grady Memorial Hospital with the diagnosis of a sickle cell disorder during a 14-month period were reviewed. Of 115 such patients, 65% had sickle cell disease and 35% had sickle cell trait. None of the former but seven of the latter group had gross hematuria. Mean age of the seven was 30 years. Comprehensive examinations and laboratory studies showed that all were free of concomitant disease. Physical findings, diagnostic modalities, and treatment were reviewed. Findings suggest that conservative therapy (bed rest, hydration, and diuresis) is usually effective.  相似文献   
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We report an unusual case in which an apparently normal upper lobe of the right lung was supplied by major systemic arterial and pulmonary arterial vessels. The anomalous artery arose from the descending aorta. Following interruption of this vessel, the machinery-like murmur previously present disappeared.  相似文献   
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OBJECTIVE: To assess the effects of angiotensin II on intracellular free Mg2+ and Ca2+ concentrations in platelets from normotensive and hypertensive subjects. DESIGN AND METHODS: Seventeen normotensive, 25 untreated hypertensive and 18 treated hypertensive patients were studied. Intracellular Mg2+ concentrations were measured with the fluorescent dye mag-fura-2-acetyoxymethylester (AM) and intracellular Ca2+ concentrations with the fluorescent dye fura-2AM under basal conditions and after stimulation by angiotensin II, saralasin (angiotensin II antagonist), arginine vasopressin and endothelin-1. The effects of increased extracellular Mg2+ concentrations on intracellular Mg2+ and Ca2+ concentrations were also determined. RESULTS: The intracellular basal Ca2+ concentration was significantly higher in the untreated hypertensives compared with the normotensives and treated hypertensive subjects (150 +/- 14 nmol/l versus 120 +/- 17 nmol/l for normotensives and 124 +/- 8 nmol/l for treated hypertensives). The basal intracellular Mg2+ concentration was significantly lower in the untreated hypertensive compared to the normotensive and treated hypertensive groups (0.37 +/- 0.08 mumol/l versus 0.58 +/- 0.09 mumol/l for normotensives and 0.52 +/- 0.11 mumol/l for treated hypertensives). In the hypertensive groups, inverse correlations were found between intracellular Ca2+ and intracellular Mg2+ concentrations (r = -0.44, P < 0.05) and between intracellular Mg2+ and diastolic blood pressure (r = -0.35, P < 0.05), while a positive correlation was found between intracellular Ca2+ and systolic blood pressure (r = 0.41, P < 0.05). Exposure of the platelets to 1 nmol/l angiotensin II significantly increased intracellular Ca2+ and significantly decreased intracellular Mg2+ concentrations in all three groups. The angiotensin II-evoked effect on intracellular Ca2+ was exaggerated in the untreated hypertensives and blunted in the treated patients (basal versus stimulated: 150 +/- 14 versus 217 +/- 20 nmol/l in untreated hypertensives; 124 +/- 8 versus 140 +/- 10 nmol/l in treated hypertensives). Saralasin (0.1 mumol/l) abolished the effects of angiotensin. Arginine vasopressin (1 mumol/l) increased the intracellular Ca2+ concentration, whereas endothelin-1 (1 nmol/l) had no significant effect on either intracellular Ca2+ or intracellular Mg2+. Increasing extracellular Mg2+ concentrations led to significant reductions in intracellular Ca2+ concentrations in all groups and a significant elevation of the intracellular Mg2+ concentration in the untreated hypertensive patients only. CONCLUSIONS: These data demonstrate a relationship between angiotensin II and intracellular magnesium and calcium. In hypertension, angiotensin II-stimulated calcium responses may be related to simultaneously decreased intracellular magnesium concentrations.  相似文献   
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