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排序方式: 共有7052条查询结果,搜索用时 46 毫秒
31.
Agata Kaczmarek Anna Katarzyna Wroska Michalina Kazek Mieczysawa Irena Bogu 《International journal of molecular sciences》2022,23(9)
The food flavour additive octanoic acid (C8:0) is also a metabolite of the entomopathogenic fungus Conidiobolus coronatus, which efficiently infects and rapidly kills Galleria mellonella. GC-MS analysis confirmed the presence of C8:0 in insecticidal fraction FR3 extracted from C. coronatus filtrate. Topical administration of C8:0 had a dose-dependent effect on survival rates of larvae but not on pupation or adult eclosion times of the survivors. Topically applied C8:0 was more toxic to adults than larvae (LD100 for adults 18.33 ± 2.49 vs. 33.56 ± 2.57 µg/mg of body mass for larvae). The administration of C8:0 on the cuticle of larvae and adults, in amounts corresponding to their LD50 and LD100 doses, had a considerable impact on the two main defense systems engaged in protecting against pathogens, causing serious changes in the developmental-stage-specific profiles of free fatty acids (FFAs) covering the cuticle of larvae and adults and damaging larval hemocytes. In vitro cultures of G. mellonella hemocytes, either directly treated with C8:0 or taken from C8:0 treated larvae, revealed deformation of hemocytes, disordered networking, late apoptosis, and necrosis, as well as caspase 1–9 activation and elevation of 8-OHdG level. C8:0 was also confirmed to have a cytotoxic effect on the SF-9 insect cell line, as determined by WST-1 and LDH tests. 相似文献
32.
The effect of compressive stress on the stability of reversed austenite in 9Ni steel was investigated by uniaxial and hydrostatic compression.It was found that the uniaxial compressive pressure promoted the γ→α transformation,while the hydrostatic pressure suppressed the γ→α transformation.The pressure dependent transformation behavior can be explained according to thermodynamic analysis. 相似文献
33.
提出了基于OrCAD/PSpice9的电路优化设计方法,介绍了OrCAD/PSpice9的特点,通过实例借助于计算机来完成数据处理、模拟评价、设计验证等工序,实现电子系统或电子产品的整个或大部分设计过程,并说明了基于OrCAD/PSpice9环境下的电路优化设计过程。 相似文献
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采用中星微VC0858在CDMA移动通信终端开发平台上实现了多媒体系统,详细介绍了硬件结构和软件系统的设计.测试结果证明该方案符合移动通信终端实际使用要求. 相似文献
36.
目的:探讨鼠重组腺病毒介导的骨形成蛋白9基因转染大鼠牙囊干细胞的可行性及其转染后的成骨作用,以获得可用于牙周骨组织再生工程的基因修饰的种子细胞。方法:取大鼠下颌骨,解剖显微镜下体外分离培养纯化鉴定牙囊干细胞,腺病毒介导的骨形成蛋白9基因转染第三代牙囊干细胞,并设立空白对照组,绿色荧光病毒组(GFP组)。通过观察细胞形态及生长曲线变化,荧光显微镜及RT—PCR检测转染后骨形成蛋白9基因mRNA的表达,碱性磷酸酶及钙茜素红染色测定转染后牙囊干细胞的成骨活性。结果:与未转染对照组比较,转染组细胞转染2周后形成钙化结节,停滞期延长,数量轻度下降,倍增时间延长。牙囊干细胞转染骨形成蛋白9基因后12h后即有荧光表达,转染3,6,9,12d后骨形成蛋白9mRNA均呈阳性表达且逐渐增强,未转染对照组呈阴性。转染组碱性磷酸酶活性随转染时间的延长呈升高趋势,ALP染色及茜素红钙结节染色为阳性:未转染对照组碱性磷酸酶染色及钙茜素红染色均呈弱阳性表达,转染组显著高于未转染组。结论:鼠重组腺病毒介导的RBMP-9基因可以成功地转染大鼠牙囊干细胞,转染后牙囊干细胞高表达骨形成蛋白9,且具有明显的成骨作用。 相似文献
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Sensors: Flexible and Stretchable 3ω Sensors for Thermal Characterization of Human Skin (Adv. Funct. Mater. 26/2017) 下载免费PDF全文
Limei Tian Yuhang Li Richard Chad Webb Siddharth Krishnan Zuguang Bian Jizhou Song Xin Ning Kaitlyn Crawford Jonas Kurniawan Andrew Bonifas Jun Ma Yuhao Liu Xu Xie Jin Chen Yuting Liu Zhan Shi Tianqi Wu Rui Ning Daizhen Li Sanjiv Sinha David G. Cahill Yonggang Huang John A. Rogers 《Advanced functional materials》2017,27(26)
39.
THREE‐DIMENSIONAL SEISMIC GEOMORPHOLOGY OF PALEOKARST IN THE CRETACEOUS MACAÉ GROUP CARBONATES,CAMPOS BASIN,BRAZIL 下载免费PDF全文
Three‐dimensional seismic data from an oilfield in the Campos Basin, SE Brazil, was used to characterize a karstified unconformity surface at the top of the Albian – Cenomanian Macaé Group. Macaé Group carbonates underwent intense karstification associated with subaerial exposure during a period of some 10 to 15 Ma resulting in the development of canyons, valleys, sinkholes and cave systems. The carbonates host commercial oil accumulations at a number of important oil fields. Understanding how the karstification process has affected the carbonates' reservoir properties is essential for future exploration, not only to improve recovery rates but also to avoid drilling‐related issues such as thief zones. In this context, this study aims to characterize the top‐Macaé Group paleokarst system by investigating the morphology of the associated reflectors recorded on seismic data, together with endokarst features in the underlying carbonate succession such as cave systems and collapse structures. The top‐Macaé Group seismic horizon can be divided into two principal geomorphological domains: highlands, characterized by abrupt relief with well‐developed erosional features; and lowlands, marked by a smoother topography. Collapse sinkholes occur in both domains and take the form of closed circular depressions. The study of endokarst features from an analysis of amplitude anomalies (bright spots) indicates the presence of heterogeneous cave systems. The interpreted data contributes to a better understanding of the spatial distribution of the paleokarst system in the Macaé Group carbonates and may assist with future hydrocarbon exploration in the Campos Basin. 相似文献
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