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1.
PurposeTo investigate the utility of diffusion kurtosis imaging (DKI) MRI for evaluation of renal fibrosis in rats with unilateral ureteral obstruction (UUO).MethodsTwenty-five rats had UUO, and ten rats were subjected to sham operation as control. DKI was performed on a 3.0 T MRI scanner on days 1, 3, 5, and 7 after ligation. All rats then underwent 18F-FDG dynamic PET to evaluate unilateral renal function, followed by histological analysis to examine α-smooth muscle actin (α-SMA) expression. DKI metrics were assessed among the time points and between two sides, and compared with maximum standardized uptake value (SUVmax), serum levels of creatinine and urea, and fibrosis marker α-SMA.ResultsMean kurtosis (MK) on day 7, axial kurtosis (Ka) on days 3 and 7, mean diffusivity (MD) on days 1, 3, 5, and 7, and fractional anisotropy (FA) on days 3, 5, and 7 of cortex and medulla between the UUO and contralateral sides were significantly different (all p < 0.05). Over the course of UUO progression, there were significant changes in Ka, MD and FA of medulla (all p < 0.05). FA of medulla was positively correlated with SUVmax (r = 0.641, p < 0.001), and MD of cortex was negatively correlated with urea (r = −0.534, p = 0.001). MD of cortex was negatively correlated with α-SMA on UUO sides (r = −0.710, p < 0.001).ConclusionsDKI shows the potential for noninvasive assessment of renal fibrosis and unilateral renal function induced by UUO.  相似文献   
2.
Cell migration proceeds in 3D matrices in vivo, which can naturally switch to distinct phenotypes for better invasion in confined microenvironments. The studies of important metabolites under confinement are extremely meaningful for comprehensive insights into cancer metastasis. The integration of cell confinement device and analytical techniques is a key point for in-situ analysis of significant metabolites in vitro.Herein, an electrochemiluminescence(ECL) sensing platform was designed for in-s...  相似文献   
3.
Novel 2-aminoimidazolone derivatives were synthesized.Most compounds displayed strong anticancer activities against human carcinoma cells in vitro.Compounds 8a,8b and 8j exhibited optimal activity superior to 5-FU in most cancer cells tested.Especially,the lC50s of 8b(12.6-21.5μmol/L) against five tumor cells were 1 -4 fold less than those of 5-FU(18.4-56.1μmol/L) in vitro.Furthermore,comp以ound 8b could induce SMMC-7721 cell apoptosis in a dose-dependent manner.Therefore,our novel findings may provide a new framework for the design of new 2-aminoimidazolone derivatives for the treatment of cancer.  相似文献   
4.
Wang  Hua  Han  Chongxu  Wang  Huimin  Jin  Qinghui  Wang  Daxin  Cao  Li  Wang  Guangzhou 《Chromatographia》2011,74(11):799-805

Lipoproteins, especially high-density lipoproteins (HDL), very low-density lipoproteins (VLDL) and small, dense low-density lipoprotein (sdLDL), are believed to play an important role in the development of atherosclerosis. In this work, a simple, selective and sensitive method for the simultaneous monitoring of these lipoproteins in human serum using microchip capillary electrophoresis was developed. Gold nanoparticles were used as an additive to the running buffer to obtain the absolute separation of the lipoproteins. Under optimised conditions, the linear ranges of large buoyant low-density lipoproteins, sdLDL, VLDL and HDL were 10–800, 10–800, 40–1,000 and 20–800 μg L−1, and their limits of detection were 5, 5, 15 and 8 μg L−1, respectively. The intraassay and interassay relative standard deviation of lipoprotein peak areas were in the range of 3.8–7.4%. For practical application, variations in the serum lipoprotein of coronary heart disease patients were monitored by microchip-based CE. The results showed that the method was applicable for routine clinical use and allowed the rapid detection of different lipoprotein classes as well as their subclasses, thus greatly improving the analysis of atherosclerotic risk factors.

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5.
Stent graft(SG), isolating the diseased vessels from the normal blood circulation and preventing the rupture of the aneurysm wall in minimally invasive surgery, is normally composed of a metallic stent and a cover with a textile structure. In this study, the electrospinning method was used to prepare a new type of cover, and the preparing conditions and the performance of the SG were investigated. The polytetrafluoroethylene(PTFE) and polyethylene oxide(PEO) were blended at the ratios of 99:1, 98:2, 97:3 and electrospun to form precursor membranes. Then they were dried in a vacuum and sintered at different temperatures under different time periods to obtain PTFE membrane, which was compounded with a stent. Their morphology, mechanical properties, water permeability and biological properties were studied. The results showed that when the membrane was sintered at 380℃ for 10 min, it had the best tensile properties. The integral water permeability of the PTFE electrospun SG was close to 0. The hemolysis rate of the SG was 2.84%, and human umbillical vein endothelial cells(HUVECs) can adhere and proliferate well on the surface of the PTFE membranes. The PTFE electrospun SG had great potential for clinical application and industrialization.  相似文献   
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7.
The interaction between a spark-generated bubble and an elastic sphere is investigated. A spark-generated bubble is created at various distances horizontally away from a suspended elastic sphere made of silicone rubber or super absorbent polymer (of shear modulus of elasticity G of between 5 and 312 kPa), using a low-voltage spark discharge method. We observe pronounced deformation and elongation of the elastic sphere when the spark-bubble is generated very close to a sphere. This happens when the elastic sphere has a small modulus of elasticity and a small size ratio R’ between the bubble and the elastic sphere (i.e. the bubble and the sphere have similar radii). Numerical simulations are also conducted using a Boundary Element Method (BEM) model coupled with a Finite Element Method (FEM) solver. The simulation results compare well with the experimental data. The numerical model is then extended to study the effects of elasticity and experimental parameters, such as the dimensionless stand-off distance H’, and size ratio R’, on the degree of deformation of the elastic cell and the dynamics of the bubble.  相似文献   
8.
This paper presents a simple and reliable method for separating the anodic peaks of dopamine (DA) and ascorbic acid (AA). Good electrochemical responses of DA and AA can be obtained at an electrochemically pretreated glassy carbon electrode (PGCE). The electrode reaction of DA is a quasi-reversible process, but the oxidation of AA is entirely irreversible. Consequently, the PGCE can be used to separate the anodic peaks of DA and AA. The separation can be higher than 290mV, and the detection limit (S/N=3) of DA is 6.0×10–8M. This PGCE is very stable and can be used for as long as four weeks.  相似文献   
9.
This paper investigates the chaotic behavior of an extended Duffing Van der pol oscillator in a ϕ6 potential under additive harmonic and bounded noise excitations for a specific parameter choice. From Melnikov theorem, we obtain the conditions for the existence of homoclinic or heteroclinic bifurcation in the case of the ϕ6 potential is bounded, which are complemented by the numerical simulations from which we illustrate the bifurcation surfaces and the fractality of the basins of attraction. The results show that the threshold amplitude of bounded noise for onset of chaos will move upwards as the noise intensity increases, which is further validated by the top Lyapunov exponents of the original system. Thus the larger the noise intensity results in the less possible chaotic domain in parameter space. The effect of bounded noise on Poincare maps is also investigated.  相似文献   
10.
非独立计数资料的内部相关性研究   总被引:3,自引:0,他引:3  
本研究探讨了非独立计数资料的内部相关性的测度方法。利用多平广义线性模型 ,导出了相应三种模型的家庭和地区内部相关系数公式 ,并用 1 992年四川省病毒性肝炎血清流行病学调查资料进行了实证性分析 ,结果符合实际。这说明本文有关非独立计数资料的内部相关系数的计算方法是合理的  相似文献   
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