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1.

Background  

Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat.  相似文献   
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 Regional cerebral blood flow changes related to the performance of two oculomotor tasks and a central fixation task were compared in ten healthy human subjects. The tasks were: (a) performance of fast-regular saccades; (b) performance of voluntary antisaccades away from a peripheral cue; (c) passive maintenance of central visual fixation in the presence of irrelevant peripheral stimulation. The saccadic task was associated with a relative increase in activity in a number of occipitotemporal areas. Compared with both the fixation and the saccadic task, the performance of antisaccades activated a set of areas including: the superior and inferior parietal lobules, the precentral and prefrontal cortex, the cingulate cortex, and the supplementary motor area. The results of the present study suggest that: (a) compared with self-determined saccadic responses the performance of fast regular, reflexive saccades produces a limited activation of the frontal eye fields; (b) in the antisaccadic task the inferior parietal lobes subserve operations of sensory-motor integration dealing with attentional disengagement from the initial peripheral cue (appearing at an invalid spatial location) and with the recomputation of the antisaccadic vector on the basis of the wrong (e.g., spatially opposite) information provided by the same cue. Received: 20 May 1996 / Accepted: 28 January 1997  相似文献   
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A new method for intraperitoneal tumour targetting in ovarian cancer using biotinylated monoclonal antibodies (MoAb) and radioactive streptavidin is described. Fifteen patients with histologically documented ovarian carcinoma were injected intraperitoneally with 2 mg of biotinylated MoAb MOv18, followed 3–5 days later by 100–150 g of indium-111 streptavidin, at the specific activity of 280–370 MBq/mg in 500 ml of normal saline. No toxicity was observed. Tumours were imaged from 2 to 48 h after radioactivity injection by recording both planar and single photon emission tomography (SPET) data. All patients underwent surgery 1–8 days later (mean 3 days) after scanning. The resected tumour and normal tissue radioactivity were measured. On the day of surgery, the tumour to normal tissue ratio was 9:1 (range 3:1–30:1) and 45:1 (range 12:1–120:1) for intra- and extraperitoneal samples, respectively. The mean tumor to blood ratio was 14:1 (range 4:1–30:1). The injected dose (i.d.) per gram of tumour was 0.112 (range 0.01–0.3) for recurrences and 0.05 for primary tumour (range 0.005–0.2). Over 24–48 h 14% i.d. (range 8–18% i.d.) was found in the urine, 14% i.d. (range 629% i.d.) in the blood and 63% i.d. (range 56–70% i.d.) was still in the peritoneal cavity. These preliminary clinical data suggest that this two-step strategy may be superior to the conventional approach (radiolabelled antibodies) for intraperitoneal radioimmunolocalization and radioimmunotherapy of ovarian cancer. Offprint requests to: G. Paganelli  相似文献   
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Abstract: Sub-clinical lung impairment, mostly represented by a reduced diffusion of alveolar gases, is a recognised complication of advanced primary biliary cirrhosis. The aim of the study was to evaluate the prevalence and type of pulmonary involvement in primary biliary cirrhosis and the relationship between lung function abnormalities and selected epidemiological and clinical variables. Sixty-one patients with different stages of primary biliary cirrhosis consecutively seen in our outpatient clinic were evaluated. The advancement of primary biliary cirrhosis was characterised by the histological stage, the presence of signs of portal hypertension and the Mayo Risk Score: a Cox regression model using serum bilirubin and albumin levels, prothrombin time, age and degree of oedema as selected variables. We measured static and dynamic lung volumes, by means of a spirometer, and diffusing capacity for carbon monoxide. Rheumatological disorders were evaluated by an independent rheumatologist. No patient complained of respiratory symptoms. Airway obstruction was present in one patient. In 24 patients (39%) the alveolar diffusion capacity was reduced. We did not find any significant relationship between diffusing capacity and smoking habits, advancement of liver disease and concomitant Sjogren syndrome. Reduced diffusion capacity showed a significant correlation with the presence of complete or incomplete CREST syndrome (p<0.01) and with the presence of circulating anti-centromere antibodies (p<0.05). Alveolar diffusion capacity is frequently impaired in patients with primary biliary cirrhosis, usually in the absence of clinical manifestations. These alterations mostly affect patients with concomitant CREST syndrome. Prospective studies are needed to evaluate if these abnormalities will eventually lead to clinical symptoms and if their progression could be influenced by different therapeutic regimens for primary biliary cirrhosis.  相似文献   
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BACKGROUND/AIMS: We studied the influence of biochemical and virologic patterns and interferon on the outcome of anti-HBe positive chronic hepatitis B in 164 (103 treated) consecutive patients, followed-up prospectively for a mean of 6 years (21 months-12 years). METHODS: Histology, biochemical and virologic profiles were characterized by monthly monitoring during the first 12 months of follow-up. Thereafter patients underwent blood and clinical controls every 4 and 6 months, respectively. Cirrhosis at follow-up histology or end stage complications of cirrhosis served as end points for the analysis of factors influencing disease progression in patients with baseline chronic hepatitis or cirrhosis, respectively. RESULTS: Disease progression was associated with older age (P<0.001), absence of previous HBeAg history (P=0.017) and higher serum HBV-DNA levels (P=0.009) (more frequently observed in unremitting disease profile, P=0.012) at multivariate analysis. Fluctuations of IgM anti-HBc levels (associated with disease exacerbations, P=0.045) correlated with end stage complications in cirrhotics (P=0.011). Disease improved in 14.6 and 1.6% of treated and untreated patients, respectively (P=0.015): interferon slowed disease progression (P<0.001). CONCLUSIONS: The outcome of anti-HBe positive chronic hepatitis B is worsened by older age and persistent viral replication or hepatitis exacerbations in chronic hepatitis or in cirrhotic patients, respectively. Interferon reduces by 2.5-folds disease progression.  相似文献   
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