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101.
臭氧水对土传病原真菌的杀灭作用 《山东科学》2021,34(4):67-72
为探寻土壤绿色消毒方法,研究不同质量浓度的臭氧水对3种土传病原真菌尖孢镰刀菌(Fusarium oxysporum)、立枯丝核菌(Rhizoctonia solani)及灰霉菌(Botrytis cinerea)的杀灭效果。结果表明:质量浓度1.0~5.0 mg/L的臭氧水对3种病原真菌的孢子都有一定的杀灭作用,臭氧水质量浓度是影响杀灭率的主要因素,作用时间对杀灭率无显著影响;提高臭氧水质量浓度及增加浇灌次数能显著增强对土壤中3种病原真菌的杀灭率;臭氧水浇灌土壤能显著降低植株的发病率,但植株的生长受到抑制,添加木霉能消除这种抑制作用。 相似文献
102.
Zhijie Fang Zhe Su Wenjing Qin Hao Li Bing Fang Wei Du Qiong Wu Bo Peng Peng Li Haidong Yu Lin Li Wei Huang 《中国化学快报》2021,31(11):2903-2908
H2S is an essential gas signal molecule in cells, and viscosity is a key internal environmental parameter. Recent studies have shown that H2S acts as a cytoarchitecture agent and gas transmitter in many tissues, e.g., as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels. Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal. It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease (PD), and the protective role of H2S in PD models has been extensively demonstrated. Herein, Mito-HS, a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H2S content. Moreover, this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H2S. The results show that H2S in mitochondria is inversely related to viscosity. The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal. This result is important for our deep understanding of PD and its causes. 相似文献
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104.
《信阳师范学院学报(自然科学版)》2017,(3):504-508
帕金森病(Parkinson’s disease,PD)是一种常见的神经退行性疾病.茶叶中特有的多酚类物质在预防神经退行性疾病方面具有重要作用.大量的体外研究表明,茶多酚在PD中通过抗氧化、铁螯合、抑制α-突触核蛋白聚集和调节细胞内信号通路等机制发挥神经保护作用.综述了茶多酚在PD模型动物和临床研究中的神经保护作用,对今后茶多酚在抗PD的研究中存在的问题和发展趋势给出了建议. 相似文献
105.
Marzena Z. Kastyak-Ibrahim Domenico L. Di Curzio Richard Buist Sheryl L. Herrera Benedict C. Albensi Marc R. Del Bigio Melanie Martin 《Magnetic resonance imaging》2013
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that is the most common cause of dementia in aging populations. Although senile plaques and neurofibrillary tangles are well-established hallmarks of AD, changes in cerebral white matter correlate with cognitive decline and may increase the risk of the development of dementia. We used the triple transgenic (3xTg)-AD mouse model of AD, previously used to show that white matter changes precede plaque formation, to test the hypothesis that MRI detectable changes occur in the corpus callosum, external capsule and the fornix. T2-weighted and diffusion tensor magnetic resonance imaging and histological stains were employed to assess white matter in older (11–17 months) 3xTg-AD mice and controls. We found no statistically significant changes in white matter between 3xTg-AD mice and controls, despite well-developed neurofibrillary tangles and beta amyloid immunoreactive plaques. Myelin staining was normal in affected mice. These data suggest that the 3xTg-AD mouse model does not develop MRI detectable white matter changes at the ages we examined. 相似文献
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107.
The identification of disease-relevant genes represents a challenge in microarray-based disease diagnosis where the sample size is often limited. Among established methods, reversible jump Markov Chain Monte Carlo (RJMCMC) methods have proven to be quite promising for variable selection. However, the design and application of an RJMCMC algorithm requires, for example, special criteria for prior distributions. Also, the simulation from joint posterior distributions of models is computationally extensive, and may even be mathematically intractable. These disadvantages may limit the applications of RJMCMC algorithms. Therefore, the development of algorithms that possess the advantages of RJMCMC methods and are also efficient and easy to follow for selecting disease-associated genes is required. Here we report a RJMCMC-like method, called random frog that possesses the advantages of RJMCMC methods and is much easier to implement. Using the colon and the estrogen gene expression datasets, we show that random frog is effective in identifying discriminating genes. The top 2 ranked genes for colon and estrogen are Z50753, U00968, and Y10871_at, Z22536_at, respectively. (The source codes with GNU General Public License Version 2.0 are freely available to non-commercial users at: http://code.google.com/p/randomfrog/.) 相似文献
108.
Exhaled breath condensate is a promising, non-invasive, diagnostic sample obtained by condensation of exhaled breath. Starting from a historical perspective of early attempts of breath testing towards the contemporary state-of-the-art breath analysis, this review article focuses mainly on the progress in determination of non-volatile compounds in exhaled breath condensate. The mechanisms by which the aerosols/droplets of non-volatile compounds are formed in the airways are discussed with methodological consequences for sampling. Dilution of respiratory droplets is a major problem for correct clinical interpretation of the measured data and there is an urgent need for standardization of EBC. This applies also for collection instrumentation and therefore various commercial and in-house built devices are described and compared with regard to their design, function and collection parameters. The analytical techniques and methods for determination of non-volatile compounds as potential markers of oxidative stress and lung inflammation are scrutinized with an emphasis on method suitability, sensitivity and appropriateness. The relevance of clinical findings for each group of possible non-volatile markers of selected pulmonary diseases and methodological recommendations with emphasis on interdisciplinary collaboration that is essential for future development into a fully validated clinical diagnostic tool are given. 相似文献
109.
Rapid and sensitive ultra‐high‐pressure liquid chromatography method for quantification of antichagasic benznidazole in plasma: application in a preclinical pharmacokinetic study 下载免费PDF全文
Marcelo Gomes Davanço Michel Leandro de Campos Rosângela Gonçalves Peccinini 《Biomedical chromatography : BMC》2015,29(7):1008-1015
Benznidazole (BNZ) and nifurtimox are the only drugs available for treating Chagas disease. In this work, we validated a bioanalytical method for the quantification of BNZ in plasma aimed at improving sensitivity and time of analysis compared with the assays already published. Furthermore, we demonstrated the application of the method in a preclinical pharmacokinetic study after administration of a single oral dose of BNZ in Wistar rats. A Waters® Acquity UHPLC system equipped with a UV–vis detector was employed. The method was established using an Acquity® UHPLC HSS SB C18 protected by an Acquity® UHPLC HSS SB C18 VanGuard guard column and detection at 324 nm. The mobile phase consisted of ultrapure water–acetonitrile (65:35), and elution was isocratic. The mobile phase flow rate was 0.55 mL/min, the volume of injection was 1 μL, and the run time was just 2 min. The samples were kept at 25°C until injection and the column at 45°C for the chromatographic separation. The sample preparation was performed by a rapid protein precipitation with acetonitrile. The linear concentration range was 0.15–20 µg/mL. The pharmacokinetic parameters of BNZ in rats were determined and the method was considered sensitive, fast and suitable for application in pharmacokinetic studies. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
110.
为探讨磁共振刀锋伪影校正(BLADE)技术提升精神疾病患者海马磁共振图像质量的效果,本文分别使用结合了BLADE技术的BLADE T2WI TSE、BLADE T2WI FLAIR及传统T2WI TSE、T2WI FLAIR四种序列,对47例精神疾病患者和美国放射学院(ACR)标准模体在3.0 T磁共振成像(MRI)设备上分别进行常规海马斜冠状位扫描和ACR标准检测.患者的磁共振图像由2名放射科医师采用5分法对运动伪影、搏动伪影、颗粒度、海马磁共振图像质量进行评价,并应用Wilcoxon符号秩检验进行数据分析.模体图像通过识别图像的钻孔阵列和轮辐的数目,半定量评价各序列的高对比空间分辨力(HCSR)和低对比物体探测能力(LCD).结果表明相比传统序列,结合BLADE技术的序列能够明显改善海马磁共振图像的运动伪影、搏动伪影(p<0.001),提高图像质量(p<0.05);但在图像颗粒度方面,传统序列表现更优(p<0.001).ACR模体半定量分析显示,结合BLADE技术序列与传统序列相比,在LCD检测方面结果更优、在HCSR检测方面结果相同或略逊.本文推荐将BLADE技术应用于不合作的精神疾病患者海马的MRI检查. 相似文献