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61.
62.
The central nervous system (CNS) controls and regulates the functional activities of the organ systems and maintains the unity between the body and the external environment. The advent of co-culture systems has made it possible to elucidate the interactions between neural cells in vitro and to reproduce complex neural circuits. Here, we classified the co-culture system as a two-dimensional (2D) co-culture system, a cell-based three-dimensional (3D) co-culture system, a tissue slice-based 3D co-culture system, an organoid-based 3D co-culture system, and a microfluidic platform-based 3D co-culture system. We provide an overview of these different co-culture models and their applications in the study of neural cell interaction. The application of co-culture systems in virus-infected CNS disease models is also discussed here. Finally, the direction of the co-culture system in future research is prospected.  相似文献   
63.
Chronic itch is one of the most prominent clinical characteristics of diverse systematic diseases. It is a devastating sensation in pathological diseases. Despite its importance, there are no FDA-labelled drugs specifically geared toward chronic itch. The associated complex pathogenesis and diverse causes escalate chronic itch to being one of the top challenges in healthcare. Humanized antibodies against IL-13, IL-4, and IL-31 proved effective in treatment of itch-associated atopic dermatitis but remain to be validated in chronic itch. There are still no satisfactory anti-itch therapeutics available toward itch-related neuropeptides including GRP, BNP, SST, CGRP, and SP. The newly identified potential itch targets including OSM, NMB, glutamate, periostin, and Serpin E1 have opened new avenues for therapeutic development. Proof-of-principle studies have been successfully performed on antagonists against these proteins and their receptors in itch treatment in animal models. Their translational interventions in humans need to be evaluated. It is of great importance to summarize and compare the newly emerging knowledge on chronic itch and its pathways to promote the development of novel anti-itch therapeutics. The goal of this review is to analyze the different physiologies and pathophysiologies of itch mediators, whilst assessing their suitability as new targets and discussing future therapeutic development.  相似文献   
64.
In this paper, a high-temperature proton-exchange membrane fuel cell (HT-PEMFC) system using fluorine-containing polybenzimidazole (6FPBI) composite membranes doped with cross-linkable polymer ionic liquid (cPIL) is developed and studied. The reliability of the model is verified by a comparison with the experimental data. The performance of the HT-PEMFC system using 6FPBI membranes with different levels of cPIL is analyzed. The results show that when the HT-PEMFC uses 6FPBI membranes with a cPIL content of 20 wt % (6FPBI-cPIL 20 membranes), the single cell power density is 4952.3 W·m2. The excessive cPIL content will lead to HT-PEMFC performance degradation. The HT-PEMFC system using the 6FPBI-cPIL 20 membranes shows a higher performance, even at higher temperatures and pressures, than the systems using 6FPBI membranes. In addition, the parametric study results suggest that the HT-PEMFC system should be operated at a higher inlet temperature and hydrogen pressure to increase system output power and efficiency. The oxygen inlet pressure should be reduced to decrease the power consumption of the ancillary equipment and improve system efficiency. The proposed model can provide a prediction for the performance of HT-PEMFC systems with the application of phosphoric-acid-doped polybenzimidazole (PA-PBI) membranes.  相似文献   
65.
Wheat stripe (yellow) rust is a worldwide disease that seriously reduces wheat grain yield and quality. Adult-plant resistance (APR) to stripe rust is generally more durable but usually controlled by multiple genes with partial resistance. In this study, a recombinant inbred line population was developed from a cross between a Chinese wheat landrace, Tutoumai, with APR to stripe rust, and a highly susceptible wheat cultivar, Siyang 936. The population was genotyped by genotyping-by-sequencing and phenotyped for APR to stripe rust in four consecutive field experiments. Three QTLs, QYr.sdau-1BL, QYr.sdau-5BL, and QYr.sdau-6BL, were identified for APR to stripe rust, and explained 8.0–21.2%, 10.1–22.7%, and 11.6–18.0% of the phenotypic variation, respectively. QYr.sdau-1BL was further mapped to a 21.6 Mb region using KASP markers derived from SNPs identified by RNA-seq of the two parents. In the QYr.sdau-1BL region, 13 disease-resistance-related genes were differently expressed between the two parents, and therefore were considered as the putative candidates of QYr.sdau-1BL. This study provides favorable gene/QTL and high-throughput markers to breeding programs for marker-assisted selection of the wheat stripe rust APR genes.  相似文献   
66.
We previously found that cordycepin inhibits the growth and metastasis formation of MDA-MB-231 cells through the Hedgehog pathway but has not validated this in vivo. In this study, we confirmed cordycepin’s anti-triple-negative breast cancer (TNBC) effect in nude mice and documented its mechanism. We found that cordycepin reduced the volume and weight of MDA-MB-231 xenografts and affected the expression of proliferation-, apoptosis-, epithelial–mesenchymal transition-, and matrix metalloproteinase-related proteins without side effects. RNA sequencing screening, pathway enrichment, and the protein network interaction analysis revealed enriched pathways and targets mainly concentrated on the Hedgehog pathway and its core components of SHH and GLI2. This indicates that the Hedgehog pathway plays a central role in the cordycepin-mediated regulation of growth and metastasis formation in TNBC. The database analysis of the Hedgehog pathway markers (SHH, PTCH1, SMO, GLI1, and GLI2) revealed that the Hedgehog pathway is activated in breast cancer tissues, and its high expression is not conducive to a patient’s survival. Finally, we verified that cordycepin effectively inhibited the Hedgehog pathway in TNBC through Western blotting and immunohistochemistry. This study found that cordycepin could regulate the growth and metastasis formation of TNBC through the Hedgehog pathway in vivo, which provides new insights for targeting and treating breast cancer.  相似文献   
67.
声波钻进技术具有速度快、岩心保真好、适用地层广等优点,广泛应用于工程勘察、环境调查、浅源地热、基础工程、矿山治理等领域.为了提高声波钻进施工质量和过程控制,美国材料与实验协会于2004年制定了第一部声波钻进规程D6914-04,后经多次修订完善,形成最新声波钻进规程D6914/D6914M-16.本文根据该版规程内容,从技术原理、钻进设备、成孔工艺等方面展开了阐述.当振动器与钻柱谐振频率重叠时,声波钻头受到的能量达到峰值.钻机和取心钻具是声波钻进的核心设备.成孔工艺主要以双管高频振动、低速回转为主,实现多种目的层的原位取心作业.标准相关内容对声波钻进技术在我国的持续推广具有参考意义.  相似文献   
68.
为了研究如何提高糖醋咕咾肉的贮藏品质和延长其保藏期,实验设计在04℃冷藏,设置4个气调处理组A(50%CO2+50%N2)、B(70%CO2+30%N2)、C(90%CO2+10%N2)和对照组D(21%O2+1%CO2+78%N2)考察其保鲜效果。结果显示:处理组C,其TBARS值、pH、细菌总数均较低,肉色稳定无任何异味。以此得出90%CO2和10%N2对咕咾肉保藏效果最佳,糖醋咕咾肉的保藏期延长至30d。   相似文献   
69.
该文提出一种基于压缩感知和三次相位变换(Cubic Phase Transform, CPT)的低复杂度空中机动目标参数估计方法。首先利用CPT将机动目标回波信号中的两个参数进行分离,然后采用压缩感知技术完成机动目标参数的估计。在机载雷达发射脉冲数有限的情况下,该方法能够获得准确的参数估计结果;仿真实验验证了该方法有效性。  相似文献   
70.
为解决在研究铁矿粉与CaO进行同化反应时通常采用最低同化温度这一终点体系指标来表征,而没有考虑同化反应速度和升温速率的缺陷以及采用多个指标来表征同化反应温度和速度在使用上的不便,本文充分利用铁矿粉在高温同化反应过程中获得的数据和范特霍夫规则,提出了量纲为1的同化反应特征数.该特征数包括同化反应速度、升温速率、同化温度和温度对同化反应速度的影响,可用来表征铁矿粉与CaO的同化过程中铁矿粉的同化温度、同化反应时间、同化反应结束温度等性能,并以烧结过程中的实际温度作为基准.该特征数综合了铁矿粉与CaO在同化反应过程中各重要信息,可以更全面地反映铁矿粉与CaO的同化反应性能.对两种方法得到的结果进行了比较,发现仅考虑最低同化温度这一终点指标时得到的结果相近,而采用同化反应特征数可以进一步细分出不同铁矿粉同化反应性能的差异.  相似文献   
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