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1.
PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent.  相似文献   
2.
口服配合点灼治疗复发性口腔溃疡的临床分析   总被引:1,自引:0,他引:1  
目的:本文用甲硝唑口服配合20%硝酸银局部点灼复发性口腔溃疡进行临床治疗,从而评价其临床使用效果。方法:于临床上收集128例患者,男70例,女58例,年龄最小12岁,最大58岁,均为复发性口腔溃疡患者,用甲硝唑口服及20%硝酸银点灼溃疡处。结果:经治疗前、后的临床追踪观察,总有效率100%,收到较理想的效果。结论:推荐口服甲硝唑配合20%硝酸银局部点灼的处理方法,于临床上使用。  相似文献   
3.
Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS).  相似文献   
4.
Chronicsofttissuelesionisaspeciallymedicalterm,andanimportantpathologicalchangesofdiseases,suchaschronicoveruseinjuriesandconversionofacuteinjuriesinlowbackorfrominter-vertebraldiscprotrusion,anddislocationofintervertebraljointsaswell,whichmainlycauseseverepaininlowback犤1犦.Manypresentmethods(oralmedicine,massage,anestheticblock,physicalthera-piesetc.)havebeenusedforrelievingthepain,whichdemandsagreatfiscalsupportannually.Unfortunately,thereportsonthemechanismsandeffectofthem…  相似文献   
5.
目的:观察胶原蛋白海绵在皮肤扩张术中的临床应用效果。方法:选择40例(个)皮肤扩张器埋置和50例(个)皮肤扩张器取出及15例自身对照的病例组,应用胶原蛋白海绵术中贴敷于渗血创面,术后观察其吸收、止血效果。结果:术中渗血于2~10min内停止,病例组中无血肿发生,术后引流量明显减少,伤口愈合时间缩短。结论:在皮肤扩张术中胶原蛋白海绵是一种良好的生物止血材料。  相似文献   
6.
采用斑点免疫金银染色(Dot-IGSS)试验对4种日本血吸虫抗原的敏感性及特异性进行比较。结果显示粗提成虫抗原(AWA)、尿素溶解性成虫抗原(JWU)、硫酸铵沉淀成虫抗原(AW)和可溶性虫卵抗原(SEA)检测40例日本血吸虫病人血清抗体的敏感性均达100.0%,40例正常人血清的可疑阳性反应分别为2.5%、0、2.5%和0,40例肝吸虫病人血清的可疑交叉率分别为2.5%、0、2.5%和0,表明在高敏感的IGSS检测系统中,粗提成虫抗原的敏感性和特异性与部分纯化者和虫卵抗原无显著性差异(P>0.05)。  相似文献   
7.
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity.  相似文献   
8.
目的 ①建立一种简便、准确、实用的人栽脂蛋白E(apoE)基因型的检测方法;②研究冠心病(CHD)患者栽脂蛋白E基因多态性。方法 应用聚合酶链反应(PCR)特异性扩增apoE基因含编码112位和158位氨基酸的基因序列,用SS—SSCP技术进行apoE基因型分析。结果 运用SS—SSCP法检测了47名冠心痛患者apoE基因型,发现ε4/2、ε3/2、ε3/3、ε4/3、ε4/4基因频率分别为4.26%,14.89%,63.83%,12.76%,4.26%,并且发现ε2、ε3、ε4等位基因频率分别是9.57%,77.66%,12.77%。结论 ①该方法简单、快速、准确,对人体无害,适合于一般实验室开展;②ε4等位基因是CHD的易患因子之一,而ε3等位基因则具有保护作用。  相似文献   
9.
Background/aim: Mid-infrared spectroscopy is a versatile method for in vivo investigation of skin after topical treatment with skin care products.
Methods: FTIR-spectrometer (Bruker Optics) with a flexible silver halide fibre probe (Infrared Fiber Sensors).
Results: Absorbance spectra from 700 to 3000 cm−1 have been recorded to gain information about proteins (amide-I and amide-II vibrations at 1650 and 1550 cm−1), esters (1740 cm−1), carboxylic acid (1710 cm−1), polyalcohols (1050 cm−1) and hydrocarbons (CH n vibrations at 2800–3000 cm−1).
Conclusions: Using the particular light guide, we were able to measure for the first time the effects of lip care products on lips directly. Furthermore, water binding and glycerol content of the skin could be determined simultaneously, as well as the replenishment of lipids by lipid-enriched bath oil.  相似文献   
10.
We report on a male patient with Pick disease who had shown severe white matter atrophy and dilatation of the lateral ventricle in the frontal lobe from an early stage. Upon admission to our hospital 2 years after disease onset, the patient showed apathy, and MRI revealed severe atrophy of the cortex and white matter of the frontal lobe. He died at age 74, 11 years after disease onset. Autopsy revealed severe atrophy of the frontal and temporal lobes, severe loss of white matter in the frontal lobe, dilatation of the lateral ventricles, and cortical thinning. Histopathological examination showed severe loss of myelinated fibers in the frontal white matter and severe neuronal loss with gliosis in the frontal and temporal cortices. Many Pick bodies were seen. Our patient had a rare case of Pick disease predominantly affecting the frontal lobe with severe involvement of the white matter from an early stage. This case suggests that myelinated fibers in the white matter as well as cerebral neurons are primarily affected in Pick disease.  相似文献   
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