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Objective Pegylated-interferon monotherapy is the standard treatment for patients with chronic hepatitis B; however, the factors associated with its therapeutic effects remain unclear. Methods Patients with chronic hepatitis B were treated with pegylated interferon α-2a for 48 weeks. We evaluated the kinetics of hepatitis B surface antigen (HBsAg) during treatment and follow-up periods and the factors associated with an HBsAg response (defined as a change in HBsAg of ≥-1 log IU/mL from baseline). Results The study population comprised 50 patients. The median baseline levels of hepatitis B virus DNA and HBsAg were 5.00 and 3.40 log IU/mL. The median values of HBsAg reduction from baseline were -0.44 (n=48), -0.41 (n=40), and -0.68 (n=11) log IU/mL at the end of treatment and at 48 and 144 weeks post-treatment, respectively. The rates of HBsAg response were 24.0% and 22.5% at the end of treatment and at 48 weeks post-treatment, respectively. A multivariate analysis identified HBsAg <3.00 log IU/mL as an independent baseline factor contributing to the HBsAg response at the end of treatment and 48 weeks post-treatment (p=1.07×10-2 and 4.42×10-2, respectively). There were significant differences in the reduction of the HBsAg levels at 12 weeks of treatment and in the incidence of serum ALT increase during treatment between patients with and without an HBsAg response. Conclusion These findings suggest that the baseline HBsAg level, HBsAg kinetics at 12 weeks of treatment, and ALT increase during treatment are important factors contributing to the HBsAg response in pegylated interferon α-2a monotherapy for patients with chronic hepatitis B.  相似文献   
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ObjectivesThe reduction of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery using an oxygen delivery-guided perfusion strategy (oxygen delivery strategy) for cardiopulmonary bypass management compared with a fixed flow perfusion (conventional strategy) remains controversial. The purpose of this study was to determine whether a oxygen delivery strategy would reduce the incidence of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery.MethodsWe randomly enrolled 300 patients undergoing cardiopulmonary bypass surgery. Patients were randomly assigned to a oxygen delivery strategy (maintaining a oxygen delivery index value >300 mL/min/m2 through pump flow adjustments during cardiopulmonary bypass) or a conventional strategy (a target pump flow was determined on the basis of the body surface area). The primary end point was the development of acute kidney injury. Secondary end points were the red blood cell transfusion rate and number of red blood cell units, intubation time, postoperative length of stay in the intensive care unit and the hospital, predischarge estimated glomerular filtration rate, and hospital mortality.ResultsAcute kidney injury occurred in 20 patients (14.6%) receiving the oxygen delivery strategy and in 42 patients (30.4%) receiving the conventional strategy (relative risk, 0.48; 95% confidence interval, 0.30-0.77; P = .002). The secondary end points were not significantly different between strategies. In a prespecified subgroup analysis of patients who had nadir hematocrit less than 23% or body surface area less than 1.40 m2, the oxygen delivery strategy seemed to be superior to the conventional strategy and the existence of quantitative interactions was suggested.ConclusionsAn oxygen delivery strategy for cardiopulmonary bypass management was superior to a conventional strategy with respect to preventing the development of acute kidney injury.  相似文献   
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《Vaccine》2022,40(33):4889-4896
BackgroundDuring the COVID-19 pandemic, the number of hepatitis B virus (HBV) vaccinations among men who have sex with men (MSM) has been considerably lower than before the pandemic. Moreover, less frequent HBV testing and a reduction in numbers of sex partners have been reported. We assessed the impact of these COVID-19-related changes on HBV transmission among MSM in the Netherlands.MethodsWe estimated the changes in sexual activity, HBV testing, and HBV vaccination among MSM during the pandemic from Dutch data. We used a deterministic compartmental model and investigated scenarios with small or large declines in sexual activity, testing, and vaccination for the current phase of the pandemic (without available data). We examined the increase in HBV vaccinations needed to prevent further increase in HBV incidence.ResultsWith a decrease in numbers of sex partners of 15–25% during the first lockdown and 5% during the second lockdown, we found a decline of 6.6% in HBV incidence in 2020, despite a >70% reduction in HBV testing and vaccination during the first lockdown. With numbers of sex partners rebounding close to pre-pandemic level in 2021, and a reduction of 15% in testing and 30% in vaccination in 2021, we found an increase of 1.4% in incidence in 2021 and 3.1% in 2026. With these changes, an increase of ≥60% in HBV vaccinations in 2022 would be needed to bring the HBV incidence in 2023 back to the level that it would have had if the COVID-19-related changes had not occurred.ConclusionsDespite reductions in sexual activity during the COVID-19 pandemic, the decrease in HBV vaccinations may result in a small increase in HBV incidence after 2021, which may persist for years. It is important to restore the vaccination level and limit further increase in HBV transmission among MSM.  相似文献   
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Surface anatomy is fundamental to clinical and surgical practices. As the surface anatomy varies with age, the purpose of this study is to provide age-standardized surface markings for the abdomen in children. A total of 155 abdominal computed tomography scans of healthy children aged 0–18 years were categorized into six groups, and the surface anatomy of the major vascular structures, solid viscera, and anatomical planes in the abdomen was analyzed. The vertebral levels of the celiac trunk, superior mesenteric artery, and hepatic portal vein formation were higher in the youngest age group, whereas the levels of the inferior mesenteric artery, formation of the inferior vena cava, and renal arteries did not differ with age. The right kidney lay between T12 and L3 and the left at T11-L3; however, both kidneys were in lower positions in younger children. The spleen was most commonly located between the 8th and 11th ribs except in toddlers. In all age groups, the hepatic portal vein formation was within the transpyloric plane and the aortic bifurcation was above the supracristal plane. In vivo reassessment of the surface anatomy enables the substantial variability of surface landmarks to be highlighted. This study demonstrates that taking account of age-related variations will increase the accuracy and therefore the clinical relevance of surface anatomy.  相似文献   
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《Cancer radiothérapie》2022,26(4):547-556
PurposeSurface-guided radiotherapy is useful for the pre-positioning and monitoring of radiotherapy. The purpose of this study was to investigate the impact of surface guidance on the repeatability of patient localization and to estimate the specific point at which high positional errors occur.Materials and methodsTen patients without the VOXELAN system (non-VXLN group) and 10 patients with the VOXELAN as the pre-positioning procedure (VXLN group) were included in this analysis. Twelve regions of interest (ROI) were defined in all the patients to verify any misalignment during radiotherapy. Thirteen ROIs were defined on the isocenter.ResultsCompared with the non-VXLN group, the translational positional errors of the VXLN group were the same for all the ROIs. The mean translational positional errors of the VXLN group in the longitudinal direction were approximately 0.1 mm, and the standard deviation was the largest among the three directions in all the ROIs. The magnitude of the standard deviation in the non-VXLN group varied independently of the ROI and direction. The standard deviations of the VXLN group in the longitudinal direction were large in all the ROIs, while the standard deviations in the vertical and lateral directions were small.ConclusionPre-positioning with a surface guidance system reduced the body twist and rotation, which could not be corrected by image-guided radiotherapy alone. Since the VOXELAN can detect positioning errors quickly and without additional radiation exposure to the patient, it can be used as a tool for pre-positioning in radiotherapy.  相似文献   
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Amorphous silica that was extracted from rice husk was used to synthesize the magMCM-41 mesoporous silica. This was then functionalized by the APTMS group in order to produce NH2-magMCM-41 as a novel and low–cost adsorbent. The XRD, VSM, N2 adsorption–desorption, FT–IR, TGA, SEM and TEM analyses were utilized to characterize the produced materials. In order to optimize the adsorption of the Pb(II) ions, the RSM (response surface methodology) was applied by using the synthesized adsorbent in aqueous solutions. A rotatable CCD (central composite design) was adopted to carry out the experiments and RSM was used to analyze them. Three independent factors namely, initial solution pH (3–7), adsorbent dosage (0.1–2 g L?1), and initial Pb(II) concentration (15–150 mg L?1) were used to investigate the removal procedure. According to the obtained results, the initial solution pH of 5.22, adsorbent dosage of 0.1 g L?1, and initial Pb(II) concentration of 150 mg L?1 were considered as the optimum conditions with 64.32% removal of Pb(II) and an adsorption capacity of 540.64 mg g?1. The maximum removal efficiency of Pb(II) ions was found to be 96.76%. The Sips isotherm model represents a better correlation with equilibrium data. It was reported by the kinetic study that data taken from the experiments fitted better to the pseudo–second–order model compared to the pseudo–first–order and intraparticle diffusion models. Finally, according to the thermodynamic study, the removal process strongly depends on temperature, which indicates an exothermic behavior and spontaneous nature of the adsorption.  相似文献   
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《Vaccine》2019,37(35):5059-5066
Background: Hepatitis B virus (HBV) infection is highly endemic in most low income countries including Cambodia. This nationwide serosurvey was conducted to assess the impact of hepatitis B vaccination and to determine whether Cambodia met the WHO regional 2017 target of hepatitis B surface antigen (HBsAg) seroprevalence less than 1% in five-year-old children.Methods: A cross-sectional multi-stage cluster survey was conducted among children born during 2010–2012 and their mothers in Cambodia. HBsAg prevalence was estimated by rapid point-of-care testing, and demographic data, including vaccination history, was collected. Vaccine coverage in children and the prevalence of HBsAg among children and mothers was calculated taking into account the complex survey design. Factors associated with children’s failure to receive timely (within 24 h) vaccination were analysed by multivariate logistic analysis.Findings: A total of 2,520 children 5–7 years old and 2,028 mothers were recruited. In total, 78.4% of children received hepatitis B vaccination birth-dose (HepB-BD); of these, 58.7% were administered ≤ 24 h. Birth at home or “other” location were independent risk factors for children’s failure to receive timely HepB-BD. Overall HBsAg seroprevalence was 4.39% (95%CI: 3.53%–5.45%) among mothers and 0.56% (95%CI: 0.32%–0.98%) among children. The prevalence among children without hepatitis B vaccination was 4.62% (95%CI: 1.31%–14.97%). Among children with a HBsAg-positive mother, prevalence was 10.11% (95%CI: 5.41%–18.11%).Interpretation: Having achieved the 2017 target of less than 1% HBsAg prevalence among 5 years old children, Cambodia can now focus on eliminating mother-to-child transmission of HBV. Moreover, the high HBsAg prevalence among mothers suggests that routine screening with proper linkage to care and treatment is needed. Strengthening measures to improve vaccination coverage further and eliminate mother-to-child transmission by coordinated programming with other services offering additional HBV interventions will help move towards the global goal of hepatitis B elimination by 2030.Funding: As per sources of funding.  相似文献   
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