糖尿病肾病中医药诊治进展

糖尿病肾病是糖尿病患者的主要微血管病变之一,亦是导致终末期肾脏病的重要原因之一。中医药诊治糖尿病肾病有多种理论学说,从不同角度阐释了糖尿病肾病的病机,其中大部分医家认为气阴两虚,肾络瘀阻为主要病因病机。文章将糖尿病肾病中医药诊治进展进行了总结。     

Photodynamic Cancer Therapy Using Wavelet Based Monte Carlo Computation of Light Absorption with a Genetic Algorithm

Objective: The method to treating cancer that combines light and light-sensitive drugs to selectively destroy tumour cells without harming healthy tissue is called photodynamic therapy (PDT). It requires accurate data for light dose distribution, generated with scalable algorithms. One of the benchmark approaches involves Monte Carlo (MC) simulations. This gives an accurate assessment of light dose distribution, but is very demanding in computation time, which prevents routine application for treatment planning. Methods: In order to resolve this problem, a design for MC simulation based on the gold standard software in biophotonics was implemented with a large modern wavelet based genetic algorithm search (WGAS). Result: The accuracy of the proposed method was compared to that with the standard optimization method using a realistic skin model. The maximum stop band attenuation of the designed LP, HP, BP and BS filters was assessed using the proposed WGAS algorithm as well as with other methods. Conclusion: In this paper, the proposed methodology employs intermediate wavelets which improve the diversification rate of the charged genetic algorithm search and that leads to significant improvement in design effort efficiency.     

MRI Brain Tumour Segmentation Using Hybrid Clustering and Classification by Back Propagation Algorithm

Generally the segmentation refers, the partitioning of an image into smaller regions to identify or locate the region ofabnormality. Even though image segmentation is the challenging task in medical applications, due to contrary image,local observations of an image, noise image, non uniform texture of the images and so on. Many techniques are availablefor image segmentation, but still it requires to introduce an efficient, fast medical image segmentation methods. Thisresearch article introduces an efficient image segmentation method based on K means clustering integrated witha spatial Fuzzy C means clustering algorithms. The suggested technique combines the advantages of the two methods.K means segmentation requires minimum computation time, but spatial Fuzzy C means provides high accuracy forimage segmentation. The performance of the proposed method is evaluated in terms of accuracy, PSNR and processingtime. It also provides good implementation results for MRI brain image segmentation with high accuracy and minimalexecution time. After completing the segmentation the of abnormal part of the input MRI brain image, it is compulsoryto classify the image is normal or abnormal. There are many classifiers like a self organizing map, Back propagationalgorithm, support vector machine etc., The algorithm helps to classify the abnormalities like benign or malignant braintumour in case of MRI brain image. The abnormality is detected based on the extracted features from an input image.Discrete wavelet transform helps to find the hidden information from the MRI brain image. The extracted features aretrained by Back Propagation Algorithm to classify the abnormalities of MRI brain image.     

药用植物中转基因元件筛查策略研究

通过对已有药用植物转基因研究文献进行总结分析,为药用植物和中药材转基因监管提供有效策略。采用关键词检索法对中国知网和SCI两大数据库进行查询,建立48种常用药用植物转基因研究中常用表达元件的数据库,分析转基因元件使用情况,并总结外源转基因的筛查策略。获得1993年4月至2016年5月的转基因研究文献281篇,包括中文文献230篇,英文文献51篇。40.4%的中文文献和54.9%的英文文献研究目的为优化药用植物遗传转化体系。常用启动子包括P-35S、P-Ubi、P-GPD和P-act,其中P-35S的使用频率最高,为68.7%。常用标记基因包括NPTII、HPT、Gent、Bar和aad A,其中NPTII的使用频率最高,为37.4%。常用报告基因包括GUS和GFP,GUS使用频率达到35.2%。常用终止子包括T-NOS、T-35S和T-OCS,其中T-NOS的使用频率最高,为58%。对各元件进行配组分析,发现"P-35S+T-NOS+NPTII+GUS"组合筛选成功率为86.1%,在此基础上加入有一定使用频率的HPT、Bar和GFP,对药用植物转基因元件的筛查率达到91.5%。对于使用同源或内源启动子、标记基因和终止子的研究,可基于T-DNA边界序列进行转基因检测。     

Multiresolution wavelet framework models brightness induction effects

A new multiresolution wavelet model is presented here, which accounts for brightness assimilation and contrast effects in a unified framework, and includes known psychophysical and physiological attributes of the primate visual system (such as spatial frequency channels, oriented receptive fields, contrast sensitivity function, contrast non-linearities, and a unified set of parameters). Like other low-level models, such as the ODOG model [Blakeslee, B., & McCourt, M. E. (1999). A multiscale spatial filtering account of the white effect, simultaneous brightness contrast and grating induction. Vision Research, 39, 4361-4377], this formulation reproduces visual effects such as simultaneous contrast, the White effect, grating induction, the Todorovi? effect, Mach bands, the Chevreul effect and the Adelson-Logvinenko tile effects, but it also reproduces other previously unexplained effects such as the dungeon illusion, all using a single set of parameters.     

Arcsine test for publication bias in meta-analyses with binary outcomes

In meta-analyses, it sometimes happens that smaller trials show different, often larger, treatment effects. One possible reason for such 'small study effects' is publication bias. This is said to occur when the chance of a smaller study being published is increased if it shows a stronger effect. Assuming no other small study effects, under the null hypothesis of no publication bias, there should be no association between effect size and effect precision (e.g. inverse standard error) among the trials in a meta-analysis.A number of tests for small study effects/publication bias have been developed. These use either a non-parametric test or a regression test for association between effect size and precision. However, when the outcome is binary, the effect is summarized by the log-risk ratio or log-odds ratio (log OR). Unfortunately, these measures are not independent of their estimated standard error. Consequently, established tests reject the null hypothesis too frequently.We propose new tests based on the arcsine transformation, which stabilizes the variance of binomial random variables. We report results of a simulation study under the Copas model (on the log OR scale) for publication bias, which evaluates tests so far proposed in the literature. This shows that: (i) the size of one of the new tests is comparable to those of the best existing tests, including those recently published; and (ii) among such tests it has slightly greater power, especially when the effect size is small and heterogeneity is present. Arcsine tests have additional advantages that they can include trials with zero events in both arms and that they can be very easily performed using the existing software for regression tests.     

Bayesian transformation cure frailty models with multivariate failure time data

We propose a class of transformation cure frailty models to accommodate a survival fraction in multivariate failure time data. Established through a general power transformation, this family of cure frailty models includes the proportional hazards and the proportional odds modeling structures as two special cases. Within the Bayesian paradigm, we obtain the joint posterior distribution and the corresponding full conditional distributions of the model parameters for the implementation of Gibbs sampling. Model selection is based on the conditional predictive ordinate statistic and deviance information criterion. As an illustration, we apply the proposed method to a real data set from dentistry.     

Somatic malignant transformation in a sacrococcygeal teratoma in a child and the use of F18FDG PET imaging

A 6-year-old female presented with a subcutaneous sacral mass. Biopsy revealed an adenocarcinoma most likely arising from a sacrococcygeal teratoma (SCT). CT imaging revealed a massive tumour consistent with SCT. F¹⁸FDG Positron Emission Tomography (PET) scan confirmed marked metabolic activity in the tumour mass and regional lymph node involvement. After chemotherapy repeat CT and PET studies revealed a poor response but no evidence of peritoneal or distant metastases. Radical abdomino-pelvic and gluteal surgery was performed with removal of the entire tumour confirmed as a moderately differentiated adenocarcinoma arising in an immature teratoma. Follow up imaging including PET scanning 5 months after her surgery revealed widespread peritoneal, hepatic and pulmonary metastases. Somatic malignant transformation of an SCT in a child of this age has not been previously reported.     

多模式CT在缺血性卒中诊疗中的应用

缺血性卒中已成为危害人类健康的主要疾病,急需一种快速有效的影像学检查协助诊断、 指导治疗、预测病因、判断预后。多模式计算机断层扫描（computed tomography,CT）检查可一次性获 取脑组织结构、血管及血流灌注等方面信息,为缺血性卒中患者个体化治疗及二级预防提供客观的 影像学依据。文章就多模式CT在缺血性卒中诊疗中的应用进行综述。