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目的 研究肝外胆管癌中VEGF-C的表达情况及其临床意义。方法 应用免疫组化Envision二步法测定32例肝外胆管癌和7例正常胆管组织VEGF-C的表达。结果 VEGF-C在肝外胆管癌和7例正常胆管组织中阳性表达率分别为53.13%,0%。胆管癌组织与正常胆管组织VEGF-C表达水平之间有显著性差异,且VEGF-C表达与胆管癌的分化程度、肿瘤大小和淋巴结转移有关。结论 VEGF-C在胆管癌的表达可促进胆管癌淋巴结的转移,对判断胆管癌淋巴结转移、评估预后有一定意义。  相似文献   
3.
放射线照射对体外培养的骨巨细胞瘤细胞作用的实验研究   总被引:1,自引:0,他引:1  
目的 :对体外培养的骨巨细胞瘤细胞进行放射线照射 ,并观察其效应。方法 :对 6例经临床、X线和病理组织学检查证实的骨巨细胞瘤标本进行体外细胞培养 ,传代后实验组进行放射线照射处理 ,对照组未进行放射线处理。分别采用倒置显微镜观察、台盼蓝染色后计数、MTT法测定和FCM分析来观察放射线照射对体外培养的骨巨细胞瘤细胞的细胞毒性和细胞周期的影响。结果 :放射线照射后 ,体外培养的骨巨细胞瘤细胞可见逐渐发生皱缩和脱落 ,细胞存活率为 8 2 7%~ 13 5 0 % ,细胞毒性指数为 83 19% ,FCM分析显示G0与G1期比例明显增加 ,G2与M期比例明显减少。结论 :放射线照射对体外培养的骨巨细胞瘤细胞有较强的细胞毒性作用  相似文献   
4.
不同状态胆囊组织的傅立叶变换红外光谱研究   总被引:4,自引:0,他引:4  
目的 探索不同生理病理状态的胆囊组织各自特异的傅立叶变换红外光谱(Fourier transform infrared spectroscopy,FT-IR)表现。方法 应用FT-IR对8例正常胆囊组织、10例炎性胆囊组织和10例胆囊癌组织进行检测,结合常规病理结果总结不同组织的光谱特征。结果 胆囊正常、炎性和癌组织具有不同的FT-IR光谱表现,1550cm^-1处的酰胺Ⅱ带在癌组织中显得较弱,峰形低平,而在正常组织中则较强,峰形高尖。1080cm^-1处核酸的吸收谱带在癌组织中较强,I1080/I1550的比值在正常组织中为0.62,癌组织中为0.87。正常组织中1450cm^-1处的峰多强于1400cm^-1处,而在癌组织中则相反。结论 胆囊正常、炎性和癌组织的FT-UR谱图不同,主要表现为组织中蛋白质、核酸和磷脂等含量与结构的改变,FT-IR有望成为胆道疾病临床诊断的一种新手段。  相似文献   
5.
目的:观察阿司匹林联合银杏叶制剂对老年高脂血症脂质、脂蛋白代谢及对血液流变学的影响.方法:将264例老年高脂血症患者随机分为两组.治疗组138例,口服银杏叶片、阿司匹林;对照组126例,口服复方丹参片.结果:降低血清总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、脂蛋白α(LPα)治疗组优于对照组(P<0.05);改善动脉硬化指数优于对照组(P<0.05).改善血液流变学多项指标两组与治疗前比较差异有统计学意义(P<0.05).结论:阿司匹林联合银杏叶制剂具有调节老年高脂血症患者脂质和脂蛋白代谢,改善血液流变学的作用.  相似文献   
6.
目的 评价蓝 -黄视野计 (blue- on- yellow perim etry,B/ Y)又称短波长视野计 (short- wavelength auto-mated perim etry,SWAP)与标准的白色视野计 (white- on- white perimetry,W/ W)在早期青光眼视野损害诊断中的意义。方法 利用 Hum phrey- - 75 0型全自动视野计 C- 30 - 2全阈值检测程序对 2 0例 (4 0只眼 )正常人、2 0例 (36只眼 )可疑青光眼、18例 (32只眼 )确诊的早期原发性开角型青光眼 (primary open- angle glaucoma,POAG)分别进行 W/ W与 B/ Y的视野检查。结果 正常人、可疑青光眼、早期青光眼 B/ Y检测的全视网膜光敏感度均值 (MS)低于 W/ W检测的结果 ,两者有显著性意义 (t=11.6 8,P <0 .0 1;t=14 .0 1,P <0 .0 1;t=14 .6 8,P <0 .0 1)。B/ Y检测光敏感度缺损均值 (MD)与 W/ W检测的结果 ,正常人组无显著性意义 (t=1.0 4 ,P <0 .0 1) ,其它两组有显著性意义 (t=4 .88,P <0 .0 1;t=3.378,P <0 .0 1)。W/ W检查正常人组与可疑性青光眼的 MS差别无显著意义 (t=2 .5 4 ,P >0 .0 1) ,B/ Y有显著意义 (t=5 .5 7,P <0 .0 1)。两组的 MD差别均有显著意义 (t=3.16 ,P <0 .0 1,t=6 .2 6 ,P <0 .0 1) ;W/ W与 B/ Y检查正常人组与早期青光眼组的 MS差别有显著意义 (t=6 .4 7,P <0 .0 ;t=10 .19,P  相似文献   
7.
The intrahippocampal kainate mouse model of mesial temporal lobe epilepsy is increasingly being used for studies on epileptogenesis and antiepileptogenesis. Almost all previous studies used male mice for this purpose, and no study is available in this or other models of acquired epilepsy that directly compared epileptogenesis in female and male rodents. Epidemiological studies suggest that gender may affect susceptibility to epilepsy and its prognosis; therefore, one goal of this study was to investigate whether sex has an influence on latent period and epileptogenesis in the intrahippocampal kainate model in mice. Another aspect that was examined in the present study was whether mouse strain differences in epileptogenesis exist. Finally, we examined the effects of different types of anesthesia (chloral hydrate, isoflurane) on kainate-induced status epilepticus (SE) and epileptogenesis. Continuous (24/7) video-EEG monitoring was used during SE and the 2 weeks following SE as well as 4–6 weeks after SE. In male NMRI mice with chloral hydrate anesthesia during kainate injection, SE was followed by a seizure-free latent period of 10–14 days if hippocampal paroxysmal discharges (HPDs) recorded from the kainate focus were considered the onset of epilepsy. Anesthesia with isoflurane led to a more rapid onset and higher severity of SE, and not all male NMRI mice exhibited a seizure-free latent period. Female NMRI mice differed from male animals in the lack of any clear latent period, independently of anesthesia type. Furthermore, HPDs were only rarely observed. These problems were not resolved by decreasing the dose of kainate or using other strains (C57BL/6, FVB/N) of female mice. The present data are the first to demonstrate marked sex-related differences in the latent period following brain injury in a rodent model of acquired epilepsy. Furthermore, our data demonstrate that the choice of anesthestic agent during kainate administration affects SE severity and as a consequence, the latent period, which may explain some of the differences reported for this model in the literature.  相似文献   
8.
A single device with extensive new functionality is highly attractive for the increasing demands for complex and multifunctional optoelectronics. Multi-field coupling has been drawing considerable attention because it leads to materials that can be simultaneously operated under several external stimuli (e.g. magnetic field, electric field, electric current, light, strain, etc.), which allows each unit to store multiple bits of information and thus enhance the memory density. In this work, we report an electro–opto–mechano-driven reversible multi-state memory device based on photocurrent in Bi0.9Eu0.1FeO3 (BEFO)/La0.67Sr0.33MnO3 (LSMO)/0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) heterostructures. It is found that the short-circuit current density (Jsc) can be switched by the variation of the potential barrier height and depletion region width at the Pt/BEFO interface modulated by light illumination, external strain, and ferroelectric polarization reversal. This work opens up pathways toward the emergence of novel device design features with dynamic control for developing high-performance electric–optical–mechanism integrated devices based on the BiFeO3-based heterostructures.

The mutual interaction between polarization switching, light and piezoelectric strain.  相似文献   
9.
勃起功能障碍及下尿路症状均为中老年男性常见疾病,多个流行病学研究证实二者密切相关。近年来多项研究证实PDE5抑制剂在改善ED患者勃起功能的同时,可有效改善患者的LUTS,但对患者的尿动力学指标无改善。本文就国内外ED与LUTS之间的联系、PDE5抑制剂治疗LUTs的进展及其可能的机制做一概述。  相似文献   
10.
Latent Low-Rank Representation (LatLRR) delivers robust and promising results for subspace recovery and feature extraction through mining the so-called hidden effects, but the locality of both similar principal and salient features cannot be preserved in the optimizations. To solve this issue for achieving enhanced performance, a boosted version of LatLRR, referred to as Regularized Low-Rank Representation (rLRR), is proposed through explicitly including an appropriate Laplacian regularization that can maximally preserve the similarity among local features. Resembling LatLRR, rLRR decomposes given data matrix from two directions by seeking a pair of low-rank matrices. But the similarities of principal and salient features can be effectively preserved by rLRR. As a result, the correlated features are well grouped and the robustness of representations is also enhanced. Based on the outputted bi-directional low-rank codes by rLRR, an unsupervised subspace learning framework termed Low-rank Similarity Preserving Projections (LSPP) is also derived for feature learning. The supervised extension of LSPP is also discussed for discriminant subspace learning. The validity of rLRR is examined by robust representation and decomposition of real images. Results demonstrated the superiority of our rLRR and LSPP in comparison to other related state-of-the-art algorithms.  相似文献   
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