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41.
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Hahn  PF; Stark  DD; Vici  LG; Ferrucci  JT  Jr 《Radiology》1986,159(2):379-382
Proper management of duodenal hematoma requires that an accurate diagnosis be made using noninvasive radiological methods. Conventional imaging may be nonspecific if there is no history of trauma or coagulopathy. Two cases of duodenal hematoma that were imaged by magnetic resonance (MR) and computed tomography (CT) are described. In both cases the hematoma had a well-defined concentric ring configuration on MR images, a finding which helped establish the diagnosis. MR imaging may provide tissue-specific characterization of duodenal hematomas.  相似文献   
43.
Elderly patients with isolated systolic hypertension (ISH)--systolic blood pressure (SBP) > or =140 mmHg and diastolic blood pressure (DBP) <90 mmHg--have increased mortality and morbidity. The aim was to study the incidence of ISH in a younger population of between 15 and 60 years of age, and to measure pulse pressure (PP), mean arterial pressure (MAP) and heart rate (HR) in these subjects. The study population consisted of 27 783 subjects, aged 15-60 years, untreated for hypertension (HT) from a cohort of employees formed to study the incidence of HT in the French working population (AIHFP). BP and HR were measured with a validated, automatic device after 5, 6 and 7 min at rest. The prevalence of ISH was 6.9% in men, 2.3% in women. This prevalence was over 5% in young men and increased at 40-44 years; it was negligible in young women, but increased at 50-54 years to about 10% (ie to the same level as in men of the same age): PP in subjects with ISH (46.9 mmHg) was significantly higher than in the normotensive group (NT-40.9 mmHg); it was comparable in both young men (65.5 mmHg) and older men (66 mmHg); it was higher in men (63.1 mmHg) than in women (61.5 mmHg). HR was higher in ISH than in NT and it was higher in women ( approximately 5 bpm) in whom it decreased with age. The prevalence of ISH is not negligible in HT (30% men, 25% women), with a high prevalence in young subjects and elevated PP, MAP and HR values. These data should be taken into account as elevated ISH, PP and HR are considered as cardio-vascular risk factors.  相似文献   
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Following recent advances in the genetics of phaeochromocytomas and paragangliomas, the members of the European Network for the Study of Adrenal Tumours (ENS@T) Phaeochromocytoma Working Group have decided to share their genotyping data and to propose European recommendations for phaeochromocytoma/functional paraganglioma (PH/FPGL) genetic testing. Germline DNA from 642 patients was analysed by ENS@T teams. In 166 patients (25.9%) the disease was familial and caused by germline mutations in VHL (56), SDHB (34), SDHD (31), RET (31) or NF1 (14), causing von Hippel-Lindau disease, SDHB- or SDHD-PH/FPGL syndromes, multiple endocrine neoplasia type 2 (MEN 2) and type 1 neurofibromatosis (NF1), respectively. In almost 60% of inherited cases it was possible to formulate a probable genetic diagnosis based on family history and/or typical syndromic presentation. Genetic testing revealed mutations in 12.7% of cases with an apparently sporadic presentation. Several clinical characteristics, such as young age at onset, the presence of bilateral, extra-adrenal or multiple tumours or a malignant tumour, should be seen as indications for genetic testing. The ENS@T Phaeochromocytoma Working Group recommends the genetic testing of all patients with PH and FPGL and suggests a practice algorithm for the management of their exploration.  相似文献   
46.
High blood pressure in early acute stroke: a sign of a poor outcome?   总被引:1,自引:0,他引:1  
OBJECTIVE: To evaluate the prognostic value of admission blood pressure in patients with acute ischemic stroke by determining whether it contributes to clinical outcome and vascular death. METHODS: We studied 230 consecutive patients admitted within the first 24 h after the onset of ischemic stroke. We used the first systolic and diastolic blood pressure measurements recorded on admission. The functional outcome was assessed on the basis of mortality or dependency (Rankin Scale > 3) at the 10-day and 6-month visits. RESULTS: High systolic blood pressure on admission was associated with poor outcome at the 10-day and 6-month visits, independent of the baseline risk factors but not of the severity of the initial stroke (odds ratio, 1.39; 95% confidence interval, 0.50-3.87). The spontaneous decrease in systolic blood pressure within the first 10 days was higher in patients with functional improvement. The admission blood pressure was not significantly associated with total and vascular deaths, except for a threshold effect of diastolic blood pressure. CONCLUSIONS: After an acute stroke, the relationship between blood pressure and clinical outcome depended on the severity of the stroke on presentation, and on the level and trend of the systolic blood pressure during the first 24 h.  相似文献   
47.
INTRODUCTION: Pheochromocytoma is a catecholamine-secreting neoplasm of chromaffin tissue. It is a rare disease. Biochemical tests should be performed only in patients at high risk of pheochromocytoma, and an imaging procedure only in those with positive biochemical tests. CURRENT KNOWLEDGE AND KEY POINTS: The most specific and sensitive diagnostic test for the disease is the determination of plasma or urinary metanephrines. The tumor can be located by computerized tomography, magnetic resonance imaging, and specific scintigraphy. Ten to 20% of pheochromocytomas result from hereditary diseases, including multiple endocrine neoplasia type 2, von Hippel Lindau disease, and neurofibromatosis 1. Familial cases are diagnosed earlier, and are more frequently bilateral and recurring than sporadic cases. About 10% of the cases are malignant either at first operation or during follow-up, malignancy being diagnosed by the presence of lymph node, visceral or bone metastases. The probability of a recurrence is positively correlated with the urinary excretion of metanephrines and tumor size. Recurrences are more frequent in cases with ectopic tumors and in those with a low plasma epinephrine to total catecholamine ratio. Patients, especially those with familial tumors or low epinephrine secretion, should be followed-up indefinitely. FUTURE PROSPECTS AND PROJECTS: Treatment for malignant recurrences includes surgery, therapeutic embolization, chemotherapy, and the application of therapeutic doses of metaiodobenzylguanidine. Metyrosine, phenoxybenzamine, or somatostatin analogs may help to control blood pressure and to alleviate symptoms in patients with malignant pheochromocytoma; however such a treatment has no antiproliferative effect.  相似文献   
48.
Endocrine hypertension represents more than half of the causes of secondary hypertension. This entity encompasses several diseases including primary aldosteronism, paraganglioma/pheochromocytoma and Cushing's syndrome. The screening of endocrine hypertension should be performed in all the patients presenting with: (1) a resistant hypertension; (2) a severe hypertension; (3) the coexistence of hypertension with an adrenal adenoma, clinical or biological abnormalities. Clinical signs and symptoms, whenever present, lack specificity, especially for primary aldosteronism where hypertension is usually the unique symptom. Screening is performed by the measurement of several hormones and by a tomodensitometry to study the morphology of the adrenals: the presence of a solitary or multiples adenomas, or hyperplasia. Pheochromocytoma and Cushing's syndrome are very uncommon and should be referred to specialized centres. Primary aldosteronism is a frequent cause of secondary hypertension. Once the diagnosis is obtained, it is essential to differentiate whether it is a surgically correctable form or not. The patients with a bilateral adrenal hyperplasia can be managed effectively by mineralocorticoids receptor antagonist. The adrenalectomy will cure or improve hypertension for the majority of the patients with a lateralized secretion of aldosterone. The diagnosis and the treatment of these disorders can be challenging. However, the diagnosis of endocrine hypertension allows diagnosing surgical correctable form of hypertension, which is not possible in essential hypertension.  相似文献   
49.
Alagille syndrome is a rare congenital multisystem disorder that may involve heart disease and pulmonary or peripheral artery stenosis. We report the clinical and radiological presentation of five adult patients with Alagille syndrome, hypertension and renal artery stenosis. All had systolic hypertension and a narrowing of the abdominal aorta, corresponding to a secondary midaortic syndrome. Renovascular disease progressed during follow-up, with increases in blood pressure, decreases in glomerular filtration rate and/or kidney atrophy. A literature review identified several anecdotal reports of Alagille syndrome associated with hypertension, renal artery stenosis and/or midaortic syndrome. We discuss this condition, focusing on diagnosis, differential diagnosis, associated conditions and management. Cardiologists, nephrologists and radiologists should be aware of this rare cause of renovascular hypertension and of the need for clinical, biological and echographic follow-up.  相似文献   
50.
Kuypers  FA; Lubin  BH; Yee  M; Agre  P; Devaux  PF; Geldwerth  D 《Blood》1993,81(4):1051-1057
In the human erythrocyte membrane phosphatidylcholine and sphingomyelin reside mainly in the outer leaflet, whereas the aminophospholipids, phosphatidylethanolamine and phosphatidylserine, are mainly found in the inner leaflet. Maintenance of phospholipid asymmetry has been assumed to involve interactions between the aminophospholipids and the membrane skeleton, in particular spectrin. To investigate whether spectrin contributes to maintaining the phospholipid transbilayer distribution and kinetics of redistribution, we studied erythrocytes from hereditary spherocytosis patients whose spectrin levels ranged from 34% to 82% of normal. The phospholipid composition and the accessibility of membrane phospholipids to hydrolysis by phospholipases were in the normal range. Spin-labeled phosphatidylserine and phosphatidylethanolamine analogues that had been introduced into the outer leaflet were rapidly transported at 37 degrees C to the inner leaflet, whereas the redistribution of spin-labeled phosphatidylcholine was slower. The kinetics of transbilayer movement of these spin-labeled phospholipid in all samples was in the normal range and was not affected by the level of spectrin. Although these erythrocyte membranes contained as little as 34% of the normal level of spectrin and were characterized by several physical abnormalities, the composition, distribution, and transbilayer kinetics of the phospholipids were found to be normal. We therefore conclude that spectrin plays, at best, only a minor role in maintaining the distribution of erythrocyte membrane phospholipid.  相似文献   
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