Effects of Rhinoncomimus latipes on the growth and reproduction of Persicaria perfoliata,an invasive plant in North America

Native to Asia, mile-a-minute Persicaria perfoliata, is an invasive weed in North America, and the weevil Rhinoncomimus latipes is a host-specific insect agent which occurs widely in China. We conducted a common garden experiment to compare P. perfoliata plant responses of native and invasive populations to herbivory by the weevils from different origins. We found weevils from Hunan, Hubei and Heilongjiang Provinces had strong, moderate and weak ability to suppress host plant, respectively. Weevils from Hunan and Hubei Provinces had stronger impact on the growth of both native and invasive plant populations than the weevil from Heilongjiang Province. The losses in seed output of invasive plants were also significantly greater than natives in the weevil treatments. Our results suggested that the weevil population from Hunan Province may be the most suitable for the control of mile-a-minute, while the population from Heilongjiang Province may be the least suitable due to climate matching.     

基于景观指数的九寨沟旅游区旅游干扰评价

旅游活动对景观格局的影响是旅游干扰的重要体现,景观指数则是反映景观格局变化的定量指标.为评价旅游干扰,本文选取景观指数,综合旅游利用幅度和旅游利用强度两方面,构建旅游干扰度指标,并将该指标用于九寨沟旅游区旅游干扰的评价.评价过程中,首先选取旅游区QuickBird遥感影像,并运用3S技术实施影像解译和分区(1～5区),5个分区海拔递增且垂直距离相等,然后计算各分区的旅游干扰度.结果表明:从1区到5区,旅游利用幅度相同,旅游利用强度总体呈递减趋势,因此,旅游干扰度总体呈递减趋势.具体来说,2区最大,其次为1区和3区,4区和5区较小.各分区旅游干扰度和平均斑块分维数之间无显著相关性,说明旅游干扰在改变土地利用形态方面作用不显著.     

Diagnostic challenges in retinitis pigmentosa: genotypic multiplicity and phenotypic variability

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders. Diagnosis can be challenging as more than 40 genes are known to cause non-syndromic RP and phenotypic expression can differ significantly resulting in variations in disease severity, age of onset, rate of progression, and clinical findings. We describe the clinical manifestations of RP, the more commonly known causative gene mutations, and the genotypic-phenotypic correlation of RP.     

伊曲康唑联合特比萘芬治疗孢子丝菌病疗效及其对病原真菌体外抗菌活性研究

目的 初步探讨伊曲康唑和特比萘芬联合治疗孢子丝菌病的疗效,评价两药体外联合对申克孢子丝菌菌丝相和酵母相的抗菌活性.方法 口服伊曲康唑200mg/d和特比萘芬250mg/d治疗孢子丝菌病;体外联合药敏试验采用棋盘微量稀释法,计算分数抑菌浓度(FIC)指数判定两药相互作用具有协同、拮抗或无关作用.结果 伊曲康唑和特比萘芬联...     

输血前检测技术的应用与展望

精准输血对疾病治疗、急诊抢救意义重大。开展输血前多项标志物检测是保障精准治疗的关键,是降低输血风险的前提。输血前检测主要是指为保证输血安全、预防交叉感染,从而对血型、凝血、感染等进行检测。其常规检测指标包括血型、交叉配血、纤维蛋白原、病毒性肝炎、人类免疫缺陷病毒和梅毒等。传统的临床输血前检测技术以免疫分析为主。随着临床救治需求由院内向现场救治拓展,电化学传感技术、微流控技术、光谱技术等新技术也逐步发展用于输血前快速检测。基于此,本文综述了不同输血前检测技术的应用场景和优缺点,分析了系列新技术在输血前检测中的应用及未来发展趋势,为推动输血前检测乃至疾病标志物快速检测技术的发展提供参考。     

单细胞拉曼技术在病原微生物检测中的研究进展

单细胞拉曼技术是基于拉曼光谱分析原理实现非培养、无标签、快速、高效、低成本揭示物质本质的新方法.近年来,单细胞拉曼技术也开始在病原微生物检测领域崭露头角.本文结合单细胞拉曼技术基本原理这一理论基础,阐述该技术在病原微生物鉴定、药物敏感性检测中的研究进展及最新技术方向,并探讨其在临床实验室应用的可行性,为未来病原微生物检...     

类器官的应用研究进展

类器官是利用干细胞的自我更新和分化能力,在体外培养形成的一种微小组织器官类似物,在很大程度上具有体内相应器官的功能。迄今为止,在3D培养条件下,已经成功培养出多种类器官如肺、胃、肠、肝和肾等类器官。它们不仅可作为组织器官的替代品用于药物和临床研究,还可用于体内器官移植。本文综述了类器官在药物毒性检测、药效评价和新药筛选中的作用以及利用类器官建立疾病模型、研究组织器官发育和类器官在精准医疗、再生医学中的价值。     

More Powerful Likelihood Ratio Tests for Isotonic Binomial Proportions

Binomial group testing involves pooling individuals into groups and observing a binary response on each group. Results from the group tests can then be used to draw inference about population proportions. Its use as an experimental design has received much attention in recent years, especially in public‐health screening experiments and vector‐transfer designs in plant pathology. We investigate the benefits of group testing in situations wherein one desires to test whether or not probabilities are increasingly ordered across the levels of an observed qualitative covariate, i.e., across strata of a population or among treatment levels. We use a known likelihood ratio test for individual testing, but extend its use to group‐testing situations to show the increases in power conferred by using group testing when operating in this constrained parameter space. We apply our methods to data from an HIV study involving male subjects classified as intraveneous drug users.     

Human cryptococcosis: relationship of environmental and clinical strains of <Emphasis Type="Italic">Cryptococcus neoformans</Emphasis> var. <Emphasis Type="Italic">neoformans </Emphasis>from urban and rural areas

Forty-five clinical and 55 environmental strains of Cryptococcus neoformans var. neoformans from São Paulo, Brazil, were tested for their susceptibilities to amphotericin B, fluconazole, itraconazole, and flucytosine by the broth microdilution method according to the National Committee of Clinical Laboratory Standards guidelines. Electrophoretic karyotypes analysis by counter-clamped homogeneous electrophoresis was used to compare their genetic relatedness. Molecular typing revealed three clinical profiles very similar to two environmental profiles and an identical environmental and clinical profile. The results showed that human cryptococcosis can be acquired from environmental strains, which had similar minimum inhibitory concentration values to clinical strains, for antifungal agents.     

Empirical Bayesian estimation of the disease transmission probability in multiple-vector-transfer designs

Plant disease is responsible for major losses in agriculture throughout the world. Diseases are often spread by insect organisms that transmit a bacterium, virus, or other pathogen. To assess disease epidemics, plant pathologists often use multiple-vector-transfers. In such contexts, groups of insect vectors are moved from an infected source to each of n test plants that will then be observed for developing symptoms of infection. The purpose of this paper is to present new estimators for p, the probability of pathogen transmission for an individual vector, motivated from an empirical Bayesian approach. We specifically investigate four such estimators, characterize their small-sample properties, and propose new credible intervals for p. These estimators remove the need to specify hyperparameters a priori and are shown to be easier to compute than the classical Bayes estimators proposed by Chaubey and Li (1995, Journal of Official Statistics 11, 1035-1046) and Chick (1996, Biometrics 52, 1055-1062). Furthermore, some of these estimators are shown to have better frequentist properties than the commonly used maximum likelihood estimator and to provide a smaller Bayes risk than the estimator proposed by Burrows (1987, Phytopathology 77, 363-365).