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Li  Zhijun  Wu  Wenjuan  Yang  Li  Gu  Liang  Zhao  Tian  Tang  Tingyu  Zhou  Xiaoxi  Qin  Guangyue 《Sleep and biological rhythms》2016,14(3):287-293
Sleep and Biological Rhythms - It is reported that the level of serum adiponectin is closely associated with status of obstructive sleep apnea (OSA). However, the effect of continuous positive...  相似文献   
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Liposome dispersions obtained from the mixture of gemini surfactants of the type alkane-α,ω-diyl-bis(alkyldimethylammonium bromide) and helper lipid DOPC create complexes with DNA showing a regular inner microstructure, identified by small angle X-ray diffraction as condensed lamellar phase (Lαc). In addition to the Lαc phase, a coexisting lamellar phase LB was also identified in the complexes formed, with periodicities in the range ~ 8.8-5.7 nm, at ionic strengths corresponding to 50-200 mM NaCl. The periodicities of LB phase did not correspond to those identified in liposome dispersion without DNA using small angle neutron scattering. The observed phase separation is shown to depend on the interplay between the surface charge density of cationic liposomes, ionic strength and method of complex preparation. The effect of ionic strength on complex formation was studied by isothermal titration calorimetry and zeta potential measurements. High ionic strength reduces the fraction of bound DNA in the complexes, and the isoelectric point is attained at a ratio of DNA/gemini surfactant which is lower than the one that can be estimated by calculation based on nominal charges of CLs and DNA.  相似文献   
3.
以3年生蒙古黄芪植株为材料,采用盆栽法模拟干旱处理,研究水分胁迫对黄芪生理状态以及其根、茎、叶中毛蕊异黄酮、毛蕊异黄酮葡萄糖苷、芒柄花素和芒柄花苷4种黄酮类化合物含量的影响。结果显示:(1)毛蕊异黄酮和毛蕊异黄酮葡萄糖苷在黄芪根、茎、叶均有分布,不同器官的毛蕊异黄酮葡萄糖苷含量表现为根叶茎,而毛蕊异黄酮含量则是叶茎根。(2)干旱胁迫下,黄芪根中毛蕊异黄酮葡萄糖苷和芒柄花苷在胁迫第8~12天有一定的积累;叶中的毛蕊异黄酮则在干旱第4~8天有明显的积累,而毛蕊异黄酮葡萄糖苷则没有明显变化。研究发现,4种黄酮类化合物在黄芪各器官中分布和含量不尽相同,同一器官中不同黄酮类化合物对干旱胁迫的响应规律也存在差异;适度的干旱胁迫能够促进黄芪毛蕊异黄酮葡萄糖苷的积累,但过度干旱胁迫则不利于其积累。  相似文献   
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獐牙菜属生药形态组织学的研究Ⅰ.   总被引:1,自引:0,他引:1  
作者较系统地研究了国产獐牙菜属生药和形态组织学特征。对其进行了详细描述并给出了性状鉴别和显微鉴别的检索表、比较表以及组织特征图。首次测量了叶的栅表比、气孔指数与气孔数。研究结果为该类生药的准确鉴定、质量评价及资源的开发利用提供了详实的科学依据。本文首先报告其中的5种,即:獐牙菜Swertia bimaculata;西南獐牙菜S. cmcta;狭叶獐牙菜S. angustifolia;紫红獐牙菜S.punicea;以及显脉獐牙菜S. neruosa。  相似文献   
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本文报道12种国产獐牙菜属和花锚属花用植物叶片的扫描电镜观察结果,并比较对照了光镜下的微形态特征。研究表明:叶片的表面纹饰以及栅表比、气孔指数等显微特征对鉴定该类药用植物有一定的价值。文中并附电镜照片、绘图和比较表等。  相似文献   
7.
Cisplatin resistance is a major challenge for bladder cancer(BC).Evidence indicates that exo-some derived from cancer-associated fibroblasts(CAF-Exo)can promote...  相似文献   
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Glycan were isolated from Cynomorium songaricum and flavone was extracted from Ginkgo leaf. This glycan was well fractionated into three fractions (CSG-F1, CSG-F1, and CSG-F3). The spectra were recorded at the absorbance mode from 4000 to 400 cm(-1) (mid infrared region) at the resolution of 8 cm(-1). The fourier transform infrared (IR) spectrum displayed a broad peak at 3438 cm(-1) and 2928 cm(-1) that corresponded to the stretching vibration of -OH group. The Ginkgo leaf flavone markedly inhibited the growth of human liver carcinoma cell line HepG2. However, C. songaricum glycan did not displayed strong antitumor activity.  相似文献   
9.
Mitochondrial control region was called “A + T-rich” region in invertebrate. In the study, the general organization of control region in mitten crab was divided into two major domains: high variable segment and conserved segment. Four conserved blocks (CSB1, CSB2, CSB3 and CSB4) and two tandem repeat sequences (RT1 and RT2) were defined in control region. There were 116 polymorphic sites and 84 parsimony information sites in 571 aligned sites of the high variable segment adjacent “tRNA-Gln”, in which 58 stable variable sites were defined between E. j. sinensis and E. j. hepuensis. Conserved domain contained more than two similar repeat units, and length polymorphism of control region was due to the number difference between the two repeat units (RT1 and RT2). And length polymorphism was a common phenomenon for tandem repeat in control region in the study. Furthermore, a novel result showed the core nucleotide of RT2 in control region tandem repeat was C in E. j. hepuensis, but G in E. j. sinensis. It might be a rapid and cost-effective measure of seedlings differentiation in aquaculture.  相似文献   
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