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971.
BACKGROUND: Interferon therapy decreases the incidence of hepatocellular carcinoma in patients with chronic hepatitis C. OBJECTIVE: To evaluate effects of interferon-alpha on recurrence after resection of hepatitis C virus-related hepatocellular carcinoma. DESIGN: Randomized, controlled trial. SETTING: University hospital, medical center, and affiliated hospital in Osaka, Japan. PATIENTS: 30 men were randomly allocated after resection to the interferon-alpha group (n = 15) or the control group (n = 15). INTERVENTION: Patients in the interferon-alpha group received interferon-alpha, 6 MIU intramuscularly daily for 2 weeks, then three times weekly for 14 weeks, and finally twice weekly for 88 weeks. MEASUREMENTS: Recurrence rates after resection. RESULTS: Recurrent tumors were detected in 5 patients in the interferon-alpha group and in 12 control patients. The recurrence rate was significantly lower in the interferon-alpha group than in the control group (P = 0.037). CONCLUSION: Postoperative interferon-alpha therapy appears to decrease recurrence after resection of hepatitis C virus-related hepatocellular carcinoma.  相似文献   
972.
High dose-dobutamine (DOB) has been previously used as a pharmacological stress test to evaluate wall motion abnormalities. As a result, recent stress echocardiography with low-dose DOB has been reported to be valuable for investigating stunned myocardium after thrombolysis. However, echocardiography requires an operator's skill and experience to evaluate wall motion abnormalities which are subjectively determined by the observer. In contrast, ultrafast computed tomography (UFCT) does not necessarily require extreme technical skill and experience. To evaluate the feasibility of stress UFCT with low-dose DOB, we scanned 10 normal subjects along the short-axis by 8-slice-multicine mode. After scanning at rest for baseline, we scanned during the administration of 4 and 8 m?g/kg/min of DOB, respectively, for 5 min. Ejection fraction, contraction, and thickening were higher during 8 m?g/kg/min of DOB than during 4 m?g/kg/min of DOB and baseline, while the above values were higher during 4 m?g/kg/min of DOB than during baseline (p < 0.01). It was possible to detect changes of cardiac function and wall motion due to low-dose DOB by UFCT. We therefore conclude that UFCT is a reliable modality for evaluating cardiac function and wall motion for low-dose DOB stress test because of its excellent spatial and contrast resolution.  相似文献   
973.
For patients who have esophageal carcinoma with tracheal invasion surgery is usually not indicated because operative complications are considerable and the prognosis is poor. We experienced complete regression of a large esophageal carcinoma with tracheal stenosis due to tumor invasion without tracheo-esophageal fistula. Irradiation of 68 Gy was delivered to a long T field from the neck to the lower thoracic esophagus, and was combined with chemotherapy using cisplatin and 5-fluorouracil. The tumor decreased markedly in size and the tracheal stenosis resolved. The patient has survived for 4 years, although second primary early esophageal carcinoma and hypopharyngeal carcinoma were detected 2 years after his initial chemoradiotherapy. Although the prognosis of advanced esophageal carcinoma with invasion of other organs is usually poor, the effect of chemoradiotherapy can sometimes be dramatic and a good result can be achieved in such patients.  相似文献   
974.
975.
Cardiac sympathetic nervous function is altered in congestive heart failure (CHF) and the uptake and washout rate of cardiac 123I-metaiodobenzylguanidine (MIBG) are useful markers for evaluating the severity of it. To assess what parameters predict decreased uptake or increased washout rate of MIBG, the concentrations of neurohumoral factor in both the aorta (Ao) and coronary sinus (CS) were measured, as well as hemodynamic parameters by catheterization, in patients with dilated cardiomyopathy (DCM). MIBG imaging was performed within 1 week of cardiac catheterization. Regarding MIBG parameters, the correlation with the transcardiac gradient of norepinephrine (NE), brain natriuretic peptide (BNP) and hemodynamics was investigated. Stepwise multivariate regression analysis was used to determine which variables closely correlated with cardiac MIBG parameters. There was a significant increase in the NE level between the Ao (446 pg/ml) and the CS (727 pg/ml). According to stepwise multivariate regression analysis, the heart/mediastinum (H/M) ratio independently correlated with the transcardiac gradient of BNP (r=-0.480, p<0.01), and the washout rate independently correlated with the transcardiac gradient of NE (r=0.481, p<0.01). These findings indicate that the H/M ratio may reflect the transcardiac gradient of BNP, which implies the degree of left ventricular dysfunction and/or damage and the washout rate may reflect altered cardiac sympathetic nerve terminal in DCM patients with CHF, suggesting that both the H/M ratio and washout rate provide important information about the failing ventricle.  相似文献   
976.
X-linked sideroblastic anemia (XLSA) is due to deficient activity of erythroid-specific 5-aminolevulinate synthase (ALAS2). We report here a patient who developed sideroblastic anemia at the age of 81 years while undergoing hemodialysis. The diagnosis of sideroblastic anemia was established by the presence of ringed sideroblasts in the bone marrow, and treatment with oral pyridoxine completely eliminated the ringed sideroblasts. We identified a novel point mutation in the fifth exon of this patient's ALAS2 gene, which resulted in an amino acid change at residue 159 from aspartic acid to asparagine (Asp159Asn). In vitro analyses of recombinant Asp159Asn ALAS2 revealed that this mutation accounted for the pyridoxine-responsiveness of this disease. The very late onset in this case of XLSA emphasizes that nutritional deficiencies caused either by dietary irregularities in the elderly or, as in this case, by maintenance hemodialysis therapy, may uncover occult inherited enzymatic deficiencies in the heme biosynthetic pathway.  相似文献   
977.
Multiplication-stimulating activity (MSA), a somatomedin purified from conditioned medium of Buffalo rat liver cells, had little effect on the intracellular level of cyclic AMP when it markedly enhanced the synthesis of sulphated glycosaminoglycans in rabbit chondrocytes in culture. In addition, MSA did not inhibit prostaglandin E1- or parathyroid hormone-induced accumulation of cyclic AMP in the chondrocytes. On the contrary, MSA slightly decreased stimulation of cyclic AMP accumulation by prostaglandin in human fibroblasts. Dibutyryl cyclic AMP and MSA increased the incorporation of [35S]sulphate and [3H]serine into proteoglycans synthesized by rabbit chondrocytes, and their effects were additive. These findings suggest that somatomedin and dibutyryl cyclic AMP enhance sulphate proteoglycan synthesis through different mechanisms. The lack of inhibitory effect of MSA on cyclic AMP accumulation may be favourable for producing additive effects with cyclic AMP on proteoglycan synthesis and DNA synthesis in chondrocytes.  相似文献   
978.
A 45-year-old woman had first been diagnosed with polymyositis because of the presence of focal necrosis, regeneration and inflammatory infiltration in the muscle fibers, and elevated creatinine phosphokinase levels. However, a pathological re-evaluation and family history led to the definite diagnosis of limb-girdle muscular dystrophy (MD). This case suggests that MD should be taken into consideration in the differential diagnosis of the inflammatory myopathies and genetic surveys including dystrophin molecule may be necessary if the condition manifests during or after adolescence, or when the family history is uninformative. In this case, the serum anti-nuclear antibody was positive, and it may represent the first time that ANA positivity has been found in limb-girdle MD.  相似文献   
979.
980.
Upshaw-Schulman syndrome (USS) is an autosomal recessive disorder characterized by repeated episodes of chronic thrombocytopenia and microangiopathic haemolytic anaemia (MAHA) that responds dramatically to infusions of fresh frozen plasma (FFP). Recent studies have provided consistent evidence that USS is a congenital deficiency of plasma von Willebrand factor-cleaving protease (VWF-CPase) activity and, therefore, unusually large VWF multimers (UL-VWFMs) are present in the plasma. However, the molecular mechanism of the clinical symptoms of USS is not well understood. We studied the relationship between UL-VWFMs and thrombocytopenia in two USS patients by analysing platelet aggregation using a mixture of the patient's plasma and normal washed platelets under high shear stress. Our results clearly showed a remarkably enhanced high shear stress-induced platelet aggregation (H-SIPA) by the patient's plasma. At 24 h after FFP infusion (approximately equal to 10 ml/kg body weight), the enhanced H-SIPA became almost completely normalized but, 2 d later, it began to return to the preinfusion level. These results were in accordance with the change in VWFM patterns. The specific effects of enhanced H-SIPA on VWF, platelet glycoprotein Ib and endogenous ADP released from platelets upon stimulation were confirmed using reagents that specifically inhibit their respective functions. Our present results clearly indicate that thrombocytopenia in USS patients is caused by a combination of the presence of UL-VWFMs, platelets and high shear stress generated in the microcirculation.  相似文献   
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