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1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage.  相似文献   
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In a prospective double-blind study, standard intravenous immunoglobulin (IVIG) was compared with an IgM-enriched IVIG in the treatment of neonatal sepsis. The two treatment groups were also compared with matched controls. One hundred and thirty babies (65 in each group) ranging from 0 to 24 days old, 480 to 4200 g in weight and born between 24 and 42 weeks of gestation who had, or were suspected of having, sepsis were given either standard IVIG or IgM-enriched IVIG (250 mg/kg per day) for 4 days in addition to supportive and antibiotic therapy. A further 65 babies who received similar supportive, antibiotic and fluids but not IVIG were used as matched controls. Mortality from infection in 'culture proven sepsis' was 3/44 (6.8%) in the IgM-enriched IVIG group, 6/42 (14.2%) in the standard IVIG group, and 11/43 (25.5%) in the control group (P = 0.017, IgM versus control, P = 0.19 standard IVIG versus control). There was no statistical difference in the outcome between the two immunoglobulin therapy groups (P = 0.25). The study indicates that IVIG improves outcome in neonatal sepsis when used as an adjunct to supportive and antibiotic therapy, but larger studies are required to confirm this.  相似文献   
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Based on the data of the First Zurich Longitudinal Growth Study we investigate how interindividual differences in adult size arise in the variables leg height, sitting height and standing height, arm length, biiliac width and bihumeral width. Specifically, we are also interested in the question of whether across sexes and variables the same growth phases and the same parameters are predictive for achieving a certain adult size. A rather complex pattern emerges, demonstrating that regulation of growth is not the same for boys and girls and moreover is not the same for the six anthropometric variables studied. Prepubertal growth is characterized by its intensity (average velocity) and by its duration. Whereas duration has by itself no appreciable influence on adult size, prepubertal intensity determines adult size to a high degree across all variables and both sexes. The intensity of prepubertal growth determines adult size to a larger degree for boys than for girls. For a given size at the end of the prepubertal period, a small duration enhances the chance of obtaining a large adult size. Compared with prepubertal growth, the amount of variance of adult size explained is small for pubertal parameters, and - with respect to linear measures - significant for girls only. A small duration of prepubertal growth is in the following mainly compensated by a stronger pubertal spurt (PS), to a varying degree across variables. The overall picture which emerges indicates that sitting height - and to a lesser extent bihumeral width - develop in a more irregular fashion than the variables biiliac width and leg height.  相似文献   
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In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres.  相似文献   
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No consistently effective therapy is yet available for the treatment of chronic HBsAg, anti-HBe, HBV-DNA-positive hepatitis. A multicenter trial has shown that the response rates are not significantly different when patients with anti-HBe-positive hepatitis are treated with six-month course of thymosin-1 or of interferon-. However, since among these patients, interferon's real efficacy is still debated, with sustained biochemical response achieved in only a few of the treated patients, we conducted this controlled study to investigate the safety and efficacy of thymosin-1 as compared with no treatment. Forty-four chronic hepatitis B virus (HBV) carriers, who were anti-HBe- and HBV-DNA-positive, were randomized, with stratification for the presence of cirrhosis at baseline liver biopsy, to receive either thymosin-1 at a dose of 900 g/m2 twice a week for six months or no treatment. At entry, both groups of patients were comparable for sex, age, liver histology, ALT, IgM anti-HBc, and HBV-DNA levels. Forty-two patients were followed-up for 20 months (median; range 12–32 months) after completion of therapy: one dropped out, and one developed hepatocellular carcinoma at six months. Thymosin-1 treatment had no side effects. Six months after the end of the therapy, HBV-DNA was negative and ALT had normalized in 14% of treated cases and in 4.5% of control group, while IgM anti-HBc was negative (<0.200) in 14% of the treated patients and in 4.5% of the controls. Among the treated patients, the median ALT levels stayed significantly lower compared to the pretreatment values during the treatment period and six months of follow-up. During the first year, there were six flares of hepatitis in the control group and five among the treated patients (P = NS), yielding a per year average of 0.3 and 0.23 flares per patient, respectively. Among the treated patients, median IgM anti-HBc levels were low with respect to baseline values 4–10 months after treatment started. None became HBsAg negative. In conclusion, these results indicate that, in anti-HBe, HBV-DNA-positive chronic hepatitis B, thymosin-1 therapy alone does not increase the response rate, but may contribute to reduce the immune-mediated liver cell necrosis as indirectly assessed by ALT and IgM anti-HBc levels.  相似文献   
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