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1.
Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle
《Journal of vascular and interventional radiology : JVIR》2020,31(12):2132-2140.e5
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.
弹性绷带在乳腺癌术后应用的效果观察 总被引:1,自引:0,他引:1
目的 观察弹性绷带在乳腺癌术后应用效果。方法 4 8例乳腺癌根治术后应用弹性绷带包扎为实验组 ,4 5例用普通宽绷带包扎为对照组。然后 ,对两组患者术后并发症进行观察。结果 实验组患者的并发症明显低于对照组 ,两组比较有显著性差异 ,P <0 .0 5。结论 应用弹性绷带包扎 ,能明显减少并发症的发生 ,促进切口愈合 ,使患者术后术侧上肢功能锻炼可以提早进行。 相似文献
3.
Alexandra A. Zaia Ricardo Delia Coletta Oslei P. Almeida Sergio R. P. Line 《European journal of oral sciences》1996,104(5-6):627-629
Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy; a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands. 相似文献
4.
目的探讨永磁速愈贴对切13的消肿止痛,促进伤口愈合和防止疤痕粘连与普通敷料进行对比观察。方法将住院行妇产科手术100例患者与同期住院的手术患者进行对比观察。结果永磁速愈贴切13愈合佳者84.0%,良好者13.0%,愈合差为3.0%,而普通敷料为28.0%、60.0%和12.0%,p〈0.01(x^2=63.660)。结论永磁速愈贴切口具有透气、保湿、促进伤口愈合、消肿、止痒,防止疤痕形成等作用。而普通敷料透气性差,保湿性差,术后切口有红肿、缝线反应、切口愈合时间长及切口局部愈合后有痛痒感。 相似文献
5.
目的 :评估 5 %次氯酸钠 (NaOCl)溶液和饱和氢氧化钙 [Ca(OH) 2 ]溶液对牙本质弹性模量和挠曲强度的影响 ,以进一步了解根管治疗过程中药物对牙齿机械性能的影响。方法 :取新鲜拔除的完整前磨牙制成标准规格牙本质条 ,经 5 %NaOCl和饱和Ca(OH) 2 溶液处理 ,三点加荷系统测定其弹性模量和挠曲强度。结果 :5 %NaOCl使牙本质弹性模量和挠曲强度显著降低 ;饱和Ca(OH) 2 溶液使牙本质挠曲强度显著降低 ,对弹性模量无显著影响 ;5 %NaOCl处理后再用饱和Ca(OH) 2 溶液处理对牙本质弹性模量和挠曲强度无进一步影响。结论 :5 %NaOCl和饱和Ca(OH) 2 溶液对牙本质的机械性能有一定影响 相似文献
6.
Belli , A. & Bosco, A. 1992. Influence of stretch-shortening cycle on mechanical behaviour of triceps surae during hopping. Acta Physiol Scand 144 , 401408. Received 20 March 1 991 , accepted 3 December 1991. ISSN 0001–6772. Laboratories of Physiology, Universities of St Etienne and Lyon, France and Departments of Biology and Physical Activity, University of Jyväskylä, Finland. Six subjects performed a first series of vertical plantar flexions and a second series of vertical rebounds, both involving muscle triceps surae exclusively. Vertical displacements, vertical forces and ankle angles were recorded during the entire work period of 60 seconds per series. In addition, expired gases were collected during the test and recovery for determination of the energy expenditure. Triceps surae was mechanically modelled with a contractile component and with an elastic component. Mechanical behaviour and work of the different muscle components were determined in both series. The net muscular efficiency calculated from the work performed by the centre of gravity was 17.5±3.0% (mean ± SD) in plantar flexions and 29.9 ± 4.8% in vertical rebounds. The net muscle efficiency calculated from the work performed by the contractile component was 17.4 %% 2.9% in plantar flexions and 16.1 ± 1.47; in vertical rebounds. These results suggest that the muscular efficiency differences do not reflect muscle contractile component efficiency but essentially the storage and recoil of elastic energy. This is supported by the relationship (P < 0.01) found in vertical rebounds between the extra work and the elastic component work. A detailed observation of the mechanical behaviour of muscle mechanical components showed that the strategy to maximize the elastic work depends also on the force-velocity characteristics of the movement and that the eccentric-concentric work of the contractile component does not always correspond respectively to the ankle extension-flexion. 相似文献
7.
This study was designed to evaluate the routine use of a gum elastic bougie for tracheal intubation. The median time to intubation with the gum elastic bougie while simulating an 'epiglottis only' view was only 10 s longer than the time taken during conventional intubation with an optimum view. Three of the patients required a gum elastic bougie-assisted intubation after attempts at conventional visual intubation had failed. There was no significant difference in the incidence of postoperative sore throat and hoarseness between the two groups. We recommend that anaesthetists should use the gum elastic bougie whenever a good view of the glottis is not immediately obtained. 相似文献
8.
Kawashima Yoshiaki Cui Fude Takeuchi Hirofumi Niwa Toshiyuki Hino Tomoaki Kiuchi Katsumi 《Pharmaceutical research》1995,12(7):1040-1044
Purpose. Poorly compressible crystals of acebutolol hydrochloride were agglomerated by the spherical crystallization technique with a two-solvent system to improve the compressibility for direct tabletting. The mechanism of improvements in static compression behaviors and tablettabilities of the spherically agglomerated crystals were investigated.
Methods. The improvement of static compression behaviors of the agglomerated crystals was determined by measuring the stress relaxations and elastic recoveries of compressed powder of original and agglomerated crystals. The improved tablettability of agglomerated crystals was evaluated by the pressure transmission ratio upon compression, the ejection pressure for releasing the tablet from the die and the tablet strength, i.e., tensile strength required for breaking.
Results. The higher relaxation pressure and the lower elastic recovery of the agglomerated crystals than of the original crystals were found. The pressure transmission ratio data showed that the friction pressures of the two crystals were similar during the compression period. The ejection pressure of the agglomerated crystals was lower than that of the original crystals. The tensile strength of the tablet of agglomerated crystals was greater than that of the original crystals.
Conclusions. The compressibility and tablettability of the spherically agglomerated crystals prepared by the spherical crystallization technique were much improved due to their increased plastic property and reduced adhesive property compared to the original crystals. 相似文献
9.
老化皮肤的胶原与弹性组织变化研究 总被引:3,自引:2,他引:1
目的:探讨光曝露情况及年龄因素对皮肤中弹性组织、Ⅰ/Ⅲ型胶原及基底膜Ⅳ型胶原的影响,进而探索皱纹形成的组织学原因。方法:对80例取自不同年龄志愿者的曝光部位(眶周/前额、面颊)及非曝光部位(腹部/臀部)的皮肤组织进行HE染色、Weigert染色、苦味酸天狼猩红染色及免疫组化处理,采用显微形态观察和半定量分析。结果:各部位皮肤基底膜内Ⅳ型胶原的含量无差异;随着曝光时间增加,前额/眶周皮肤中Ⅰ型胶原减少率最大,弹性变性物质增加率最大。结论:前额/眶周皮肤的胶原显著减少和弹性变性物质明显增生,是该部位皮肤皱纹早发的重要原因。 相似文献
10.
本实验就复方硅橡胶栓堵剂(CSR)对家兔输卵管上皮细胞趋微结构的影响进行了观察分析,并测定了上皮细胞内铜元素的含量变化,电镜观察表明:家充输卵管经复方硅橡胶栓堵后,其上皮细胞表面结构、细胞连接、细胞核等超微结构均未发生明显的形态改变:注药侧(右侧〕和对照侧(左侧)输卵管上皮细胞内虽有少数线粒体膨胀,但两组间无论在线粒体数目,膨胀线粒体百分率以及线粒体外膜比表面等方面均无差异(P>0.1),电镜X—时线能谱分析表明:注药侧输卵管上皮细胞内铜元素的相对含量咯高于对照组,而且铜元素多畜集于线粒体内。 相似文献