Iterative reconstruction algorithms

In this paper a survey of recent results on iterative reconstruction algorithms is given. These results, many of which have not yet appeared elsewhere, are applicable to a very general formulation of the reconstruction problem based on the series expansion approach. A set of optimization criteria and a number of iterative reconstruction algorithms are stated, together with theorems on the convergence of the algorithms to optimum images. The efficacy of the algorithms is compared to that of the convolution method. In particular, the falseness of the claim that ART and the backprojection method are the same is demonstrated.     

南昌链霉菌生物合成梅岭霉素种子制备优化

以参数相关理论为指导,优化南昌链霉菌生物合成梅岭霉素种子制备工艺。结果表明,培养20～35h后,pH7.30～7.50,总糖<0.35%,pmv>10%,溶磷<100μg/ml,菌丝分化启动有利于提高梅岭霉素的发酵效价。     

Taguchi L16 orthogonal array approach for optimization of fluoride removal from aqueous solution using Saccharum spontaneum weed grass novel biosorbent

Optimization of operating and design parameters is needed for the greater application to achieve higher quality, performance, and minimum cost. The paper mainly concentrates on, the optimization of process parameters influencing the deflouridation of water by Analysis of mean (ANOM) approach. The current work mainly aims at the utilization of the Taguchi approach to optimize influencing operating parameters for maximizing the removal of fluoride under batch experimental studies by using biosorbent developed from Saccharum spontaneum, weed plant. The optimum conditions were found at pH 7, sorbate content 5 mg/L, period of contact 120 min, sorbent dosage 10 g/L, and temperature 30 °C. The percent part of various process parameters is obtained in the successive sequence pH 56.21% > initial concentration of adsorbate 33.94% > biosorbent dose 5.49% > contact time 3.35% > temperature 1.01%. The equilibrium study indicates fluoride sorption on Saccharum spontaneum adsorbent fulfill the Langmuir model with parameters ‘a' and ‘b' determined as 1.617 mg/g and 0.473 L/mg. The kinetic study with sorption data suggested the Pseudo-second order kinetic model as best fitting with kinetic rate k₂ 0.218 g/mg min. The thermodynamic analysis suggested a spontaneous and endothermic nature (ΔH = 16.268 kJ/mol). Characterization of adsorbent was done using BET, SEM, and also by the determination of textual properties. Regeneration of the biosorbent is done for three cycles and is used for fluoride removal.     

阿奇霉素有关物质测定方法的优化分析

目的采用色谱分析法对阿奇霉素相关物质的进行测定,探讨测定方法的优化。方法采用相色谱系统仪器、岛津Class-10Avp系统完成测定,色谱柱为SHISEIDO CAPCELL PAK C18 MG,规格为5μm,250mm×4.6mm。流动相为磷盐酸缓冲液,以0.05mol/L的磷酸氢二钾溶液,以浓度为20%的磷酸调节,直至pH值为8.2;色谱纯试剂乙腈为45∶55;色谱柱温度为30℃;流速为每分钟10mL;检测波长为210nm;进样量为50μL。结果溶液浓度为10~1000μg/mL的范围内的线性关系,结果表明线性关系良好。方法的最低检出限为100ng,r=0.9999。结论本次研究所采用的测定方法能够有效测定阿奇霉素中的相关物质,具有良好的分离性与浓度峰面线性关系。     

Quel « PRP » pour traiter les tendinopathies chroniques ?

Plasma rich platelets (PRP) consist of blood plasma with a high concentration of platelets autologous constituting a huge reservoir of growth factors. The clinical use of the PRP is widespread in various medical applications. Even it is very popular with athletes, the use of PRP in tendinopathies is still scientifically discussed, particularly related to a disparity in the products called PRP. In order to optimize employment, it should be interested in the different stages of obtaining of the PRP. In this literature review, we analyzed in particular 8 parameters that can influence the quality of the PRP: (1) anticoagulants used to preserve the best feature of platelet; (2) centrifuge speeds used in order to extract platelets; (3) platelet concentrations and the presence of leukocytes and erythrocytes in the PRP; (4) the platelet activators for the mast of platelets and thus the release of growth factors; (5) use of local anesthetics to achieve infiltration, in addition to these parameters, it might be interesting to analyze other variables like: (6) employment or not of buffer to neutralize the acidity caused by anticoagulants; (7) injection under US guidance or not; and (8) volume of PRP injected to determine their influence on the healing potential.     

响应面法优化广金钱草中总黄酮的酶法提取工艺

目的 采用响应面法优化广金钱草中总黄酮的酶法提取工艺.方法 在单因素试验的基础上,根据Box-Behnken设计原理,采用四因素三水平响应面分析方法,考察酶解时间、温度、酶用量和pH值对总黄酮得率的影响,建立二次多项式回归方程的预测模型,绘制以总黄酮含量为响应值的等高线图和响应曲面,讨论各因素间的交互作用.结果 确定了酶法提取工艺的最佳参数为:以60％乙醇提取、料液比为1∶50、0.23％纤维素酶、酶解1.49 h、酶解温度为30.55℃、pH5.52;实际测得总黄酮的得率为6.560 mg·g-1,与预测值6.481 mg·g-1相近.结论 酶法提取广金钱草中总黄酮的反应条件温和,可避免破坏有效成分的结构;优选的工艺稳定可行,提高了提取效率.     

Optimization of azathioprine dose in combined treatment with anti-TNF-alpha in inflammatory bowel disease

IntroductionThe dose of thiopurine drugs in combined treatments with anti-TNF in inflammatory bowel disease (IBD) has not been clearly established. The purpose of this study is to assess whether the dose of azathioprine influences clinical and biochemical response/remission rates, and anti-TNF drug levels/antibody formation.Material and methodsPatients with IBD on combined maintenance treatment with azathioprine and infliximab or adalimumab were selected. Based on the dose of azathioprine, two groups were defined (standard: 2–2.5 mg/kg/day; and decreased: less than 2 mg/kg/day).ResultsIn the IFX group, there were no statistically significant differences (p = 0.204) in the rates of remission (39% vs 41.3%), response (10% vs 21.7%) or failure (51.5% vs 37%) depending on the dose of thiopurine drugs. No differences were found between AZA-dose dependent IFX levels (2.46 vs 3.21 μg/mL; p = 0.211). In the adalimumab group, there were no statistically significant differences (p = 0.83) in the rates of remission (66% vs 56%), response without remission (15.38% vs 25%) or failure (18% vs 18%) depending on the dose of thiopurines. With respect to ADA-levels, no differences were found in both groups (7.69 vs 8.23 μg/mL; p = 0.37).ConclusionIn our experience, no statistically significant differences were found in either anti-TNF levels or clinical-biological response/remission rates based on doses of azathioprine.     

云计算环境下网络医学信息资源服务模型的构建

阐述了云计算的原理及优点,并针对网络医学信息资源及其利用存在的问题,提出了构建云计算环境下网络医学信息资源服务模型。该模型可有效整合异构环境的资源、实现资源优化配置、优化网络医学信息资源服务、避免重复建设医学信息资源、减少人力财力的浪费、提高资源共享与利用。