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51.
ZHANG Xu LIU Ming-ming CHENG Ming XU Jin WANG Shu-he WANG Hui REN Ya-li XIU Rui-juan WANG Su-xia 《园艺学报》2015,31(8):1520
AIM: To investigate the ultrastructural changes of islet microvascular endothelial cells in STZ-induced type 1 diabetic mice. METHODS: BALB/c mice were randomly divided into diabetic group and control group. The expression of insulin and platelet-endothelial cell adhesion molecule-1 (CD31) in islet microvessels was detected by immunohistochemical staining. The ultrastructural changes of islet β cells and islet microvessels were observed under transmission electron microscope. RESULTS: Compared with control group, the number of islet β cells, ratio of β cells/α cells, average number of secretory granules in β cells and insulin expression area per islet in diabetic group were significantly decreased (P<0.01). Besides, diabetic group had fewer microvessels with lower expression of CD31 (P<0.01). Mitochondria in islet microvascular endothelial cells and pericytes in diabetic group were swelling. The basement membrane of islet microvessels became thicker in diabetic group (P<0.01). CONCLUSION: Islet microvascular endothelial cells were impaired in type 1 diabetic mice. 相似文献
52.
肌肉参与机体的运动、协调和体温调节等一系列生命活动,同时畜禽肌肉是人类重要的蛋白质来源。肌肉发生过程中的不同调控机制可引起肌肉发育的阶段性差异,而整个肌肉发育主要以两个时期(胚胎期和出生后)的发育状态体现。长链非编码RNA(lncRNA)是一类不具有蛋白编码能力且长度>200 nt的RNA分子。近年来,随着基因组学和分子生物学技术的高速发展,发现lncRNA广泛参与到肌肉发育的各个阶段,以多种作用机制调控肌肉的发育过程。作者介绍了肌肉的发育过程,综述了目前发现的与肌肉发育相关的lncRNAs及其作用机制,并阐述其在肌肉发育的不同阶段发挥的重要作用,为进一步研究肌肉发育相关lncRNAs提供了参考。 相似文献
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54.
为探讨高光谱分析技术在草坪草水分监测上的应用,以草地早熟禾、高羊茅、多年生黑麦草为试验材料,测定了干旱胁迫下3种冷季型草坪草生理指标及光谱反射率。结果表明:随着干旱胁迫程度的加深,供试草坪草叶片相对含水量和叶绿素含量显著下降(P0.05),丙二醛含量、脯氨酸含量及敏感波段的(550和760 nm)的光谱反射率显著上升(P0.05),3种草坪草抗旱性能的强弱顺序为:高羊茅多年生黑麦草草地早熟禾。3种草坪草敏感波段光谱反射率(R_(550 nm),R_(760 nm))及高光谱参数(Rg,R0,GNDVI)与生理指标间呈显著或极显著相关,以R_(550 nm)与生理指标间的相关系数绝对值最大。同时R_(550 nm)构建了供试草坪草生理指标的估测模型,经检验,模型估测值与实测值相关性达显著或极显著水平。 相似文献
55.
岩棉育苗块持水量对番茄幼苗生长的影响 总被引:1,自引:0,他引:1
设施土壤次生盐渍化和连作障碍日益严重,岩棉无土栽培是解决诸类问题的途径之一。以"双抗1号"番茄品种为试材,在日光温室条件下,研究了岩棉块育苗期间不同相对持水量(30%、40%、50%、60%、70%)对番茄幼苗株高、茎粗、鲜重、干重的影响。结果表明:较高的岩棉块持水量对番茄幼苗株高有明显的促进作用;育苗结束时不同持水量处理对番茄幼苗茎粗的影响差异不显著;较高持水量处理能显著增加番茄幼苗地上部鲜重和干重,能明显促进根系生长,增加岩棉育苗块底面的根系密度。初步建议岩棉块培育番茄苗时宜采用60%~70%相对持水量。 相似文献
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57.
With the goal of the sintering of magnetite concentrates without carbon,the effect of quality,inert atmosphere and Fe_3O_4 addition on microwave sintering of magnetite concentrates is studied.It is shown that: With the same basicity(CaO/SiO_2=2.5) and microwave heating condition(1000W,2.45GHz,20min),the centre temperature decreaseds with a increasing sample mass;There is no great difference between with and without inert atmosphere in microwave sintering of magnetite in a same microwave heating condition.When 100g sample(CaO/SiO_2=2.5) is heated by microwave irradiation(1000W,2.45GHz,20min),the more Fe_3O_4 is added,the less liquid phase is produced,which is bad for microwave sintering of magnetite concentrate. 相似文献
58.
The high-speed access for medical digital image sequences was restricted to special device and complicated system in the past. The authors present a new method of high-speed access for medical digital image sequences which can be performed on general computer by means of the combination of Serial ATA(SATA) and Redundant Array of Independent Disk(RAID).Then they introduce the scheme of system configuration and software program. Lastly the testing result is given and the speediness,cheapness and conveniency of this method are elucidated. 相似文献
59.
REN Guang-sheng 《保鲜与加工》2001,(3):22-25
Characteristics of a tire are the foundation of vehicle dynamics studying, especially play a vital role in vehicle handling study. It is necessary to establish a tire model in the simulation for vehicle handling because the tire characteristics got by test can not be satisfied.The optimization of fitting to the tire test data curves by Magic Formula is discussed, included the digitalization of tire test data curves, designing objective functions and optimization processes,etc. Finally the parameters in Magic Formula tire model are obtained and they lay a foundation for the development of vehicle handling aftertime. 相似文献
60.
Audit takes a unique status and has obvious function in financial surveillance system.The Audit is used to superintend the factuality,validity and virtue of fiscal and financial income and expenses.In the renewed China Audit law the functions and status of official audit have been intensified,and the qualification and status of Audit department as executing office is confirmed.This paper analyzed the official construction project audit's function and legal status. 相似文献