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1.
PurposeTo compare the characteristics of polidocanol (POL) and ethanolamine oleate (EO) sclerosing foams produced by a Shirasu porous glass membrane (SPGM) device with those made using a 3-way stopcock (3WSC).Materials and MethodsFoam half-life times were measured in an ex-vivo benchtop study. Computed tomography (CT) images of each foam were obtained over the time course, and a CT texture analysis was conducted. The bubble size in each foam was measured by an optical microscope.ResultsMedian foam half-life times were longer in the SPGM group than in the 3WSC group (POL: 198 vs 166 s, P = .02; EO: 640 vs 391 s, P < .01). In the CT texture analysis, median standard deviation (SD) and entropy (randomness) were lower, and median energy (uniformity) and gray-level cooccurrence matrix (GLCM) homogeneity were higher in the SPGM group than in the 3WSC group (POL SD: at 30 s and 50–300 s; POL entropy: at 0–60 s; EO SD: at 0–600 s; EO entropy: at 0–460 s; POL energy: at 0–40 s; POL GLCM homogeneity: at 0–250 s; EO energy: at 0–360 s; EO GLCM homogeneity: at 0–480 s; all P < .05). Median bubble diameters in the SPGM group and in the 3WSC group were 69 and 83 μm (P < .01), respectively, in the POL foam; and 36 and 36 μm (P = .45), respectively, in the EO foam.ConclusionsPOL and EO foams had greater uniformity and longer foam half-life time when prepared with an SPGM device than with a 3WSC.  相似文献   
2.
《中国现代医生》2020,58(36):77-80
目的 分析硫酸镁联合孟鲁司特钠对重度哮喘患儿肺功能及呼吸动力学的影响。方法 选取2018 年6 月~2020 年6 月本院收治的78 例重度哮喘患者,以双盲随机抽样法分组,每组各39 例。对照组采用硫酸镁治疗,实验组采用硫酸镁联合孟鲁司特钠治疗,比较两组临床疗效、肺功能指标、呼吸动力学指标、不良反应发生率。结果 实验组临床总有效率(94.87%)较对照组(64.10%)高;治疗2 周后,实验组FEV1、PEF、FVC、Cst 均较对照组高;治疗2 周后,实验组Pawm、Plat、R 均较对照组低,差异均有统计学意义(P<0.05)。两组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 硫酸镁联合孟鲁司特钠可有效缓解重度哮喘患者临床症状,改善肺功能及呼吸动力学参数,且不良反应较少,值得借鉴。  相似文献   
3.
张涛  苏晓兰  毛心勇  刘倩  吴宝麒  魏玮 《北京中医药》2020,(3):205-210,F0003
目的探讨胃肠安丸对葡聚糖硫酸钠(DSS)诱导溃疡性结肠炎小鼠的治疗作用及机制。方法SPF级C57BL/6小鼠60只,除正常对照组小鼠外,其余小鼠均给予2.5%DSS水溶液,自由饮用7 d制备溃疡性结肠炎模型,模型评价后再随机分为模型组、美沙拉嗪组及胃肠安丸高剂量组、中剂量组、低剂量组。胃肠安丸低、中、高剂量组分别给予0.015、0.03、0.06 g/(kg·d)胃肠安丸混悬液0.5 mL灌胃,1次/d;美沙拉嗪组给予0.52 g/(kg·d)美沙拉嗪混悬液0.5 mL灌胃,1次/d;正常对照组和模型组给予等体积纯水灌胃,均连续干预10 d。对比各组小鼠疾病活动指数(DAI)评分、结肠长度,用HE染色观察小鼠结肠组织病理形态学变化,用流式细胞术检测脾组织中Treg、Th17、CD4^+、CD8^+细胞百分比,ELISA法检测血清细胞因子TNF-α、IL-6、IL-8、IL-10、CRP水平。结果药物干预过程中,各组小鼠体质量均逐日增加,腹泻、便血、体质量下降等症状逐日缓解,与模型组相比,美沙拉嗪组和胃肠安丸高剂量组能更快地缓解上述症状,2组DAI评分逐日下降(P<0.05)。药物干预结束后,与模型组比较,胃肠安丸高剂量组和美沙拉嗪组小鼠结肠较长(P<0.05),结肠组织充血、间质水肿及炎性细胞浸润较轻,CD4^+、CD8^+、Treg细胞百分比及血清IL-10水平较高(P<0.05),Th17细胞百分比及血清TNF-α、IL-6、IL-8、CRP水平较低(P<0.05)。结论胃肠安丸对DSS诱导的小鼠肠道黏膜损伤有一定的修复作用,其作用机制可能与恢复Treg/Th17免疫平衡以及调节相关细胞因子水平有关。  相似文献   
4.
目的观察硫酸镁治疗急性脑梗死的疗效,分析镁离子对急性脑梗死患者美国国立卫生研究院卒中量表评分(NIHSS)及神经元特异性烯醇化酶(NSE)的影响。方法选择2016年3月-2019年9月在广东省潮州市人民医院住院治疗的急性脑梗死患者100例,根据掷币法随机分为观察组50例和对照组50例。对照组采用综合治疗,观察组在对照组治疗基础上联合硫酸镁治疗。比较2组患者治疗前后NIHSS评分、NSE水平及临床疗效和不良反应发生情况。结果2组治疗后NIHSS评分均低于治疗前(P<0.05),且观察组NIHSS评分低于对照组(P<0.05)。治疗第5天,2组NSE均升高(P<0.05),但观察组低于对照组(P<0.05);治疗第10天,2组NSE均低于治疗前和治疗第5天(P<0.05),且观察组低于对照组(P<0.05)。观察组总有效率为88.0%高于对照组的70.0%(P<0.05)。2组均未见严重不良反应发生。结论硫酸镁可为急性脑梗死的辅助治疗提供新的方法。  相似文献   
5.
目的讨论思考丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗小儿变异性哮喘的临床效果。方法抽选于2018年12月-2019年12月期间本院儿科门诊共收治的小儿变异性哮喘患儿72例入组,根据计算机随机分组法均分为两组。对照组(n=36)给予丙酸氟替卡松联合硫酸沙丁胺醇吸入治疗,研究组(n=36)给予丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗。评价及对比两组的疗效、T淋巴细胞含量、血清生化指标。结果研究组的疗效高于对照组(P<0.05);研究组的血清生化指标均优于对照组(P<0.05);研究组的CD4^+、CD4^+/CD8^+含量低于对照组,且CD8^+含量高于对照组(P<0.05)。结论丙酸氟替卡松、硫酸沙丁胺醇吸入联合维生素D3治疗小儿变异性哮喘,疗效确切,可协同增效、相互补充,缓解症状,维持T淋巴细胞亚群平衡,减轻炎症反应,值得临床借鉴应用。  相似文献   
6.

Background

Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.

Methods

We decellularized human IMAs and performed histologic evaluations and scanning electron microscopy to confirm the decellularization process and the preservation of the extracellular matrix. Subsequently, we grafted the scaffolds into the superficial femoral arteries of 8 New Zealand rabbits with an end-to-end anastomosis. Computed tomography angiograms were provided at 3, 12, and 36 months postoperatively. Subsequently, the animals were killed, and biopsies were taken for histologic and immunohistochemical assessments.

Results

Evaluation of the acellular tissue confirmed the efficacy of the decellularization protocol and the preservation of the extracellular matrix. All 8 animals survived the entire follow-up period. Doppler ultrasonography and computed tomography angiographies verified the conduit's patency. Histologic assessments depicted the recellularization of all 3 layers of the scaffold. Smooth muscle cells were detected in tunica media. Immunohistochemical assessments confirmed these findings.

Conclusions

In conclusion, we demonstrated that acellular human IMA could be used as an efficient small-diameter vascular substitute with high patency. These findings could pave the path for future investigations on the clinical application of acellular IMA as a novel vascular graft for small-diameter bypass surgeries.  相似文献   
7.
8.
Spondyloepimetaphyseal dysplasias (SEMDs) belong to a clinically and genetically heterogeneous group of inherited skeletal disorders defined by a defect in the growth and shape of vertebrae, epiphyses and metaphyses. Rhizomelic SEMD is characterized by a disproportionate small stature caused by severe shortening and deformation of the limbs’ proximal bones, with the cranio-facial sphere unaffected. We report a second individual, an 8-year-old girl, with autosomal recessive rhizomelic SEMD associated with a homozygous exonic missense variant, c.226G > A p.(Glu76Lys), in GNPNAT1 identified by trio genome sequencing. Our data corroborate the recent findings of Ain et al. and further delineate the clinical and radiographic features of this form of SEMD associated with rhizomelic dysplasia while outlining a potential hotspot in this newly described genetic disorder.  相似文献   
9.
A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.  相似文献   
10.
Poly(ε-caprolactone) (PCL) was mixed with submicron particles of barium sulfate to obtain biodegradable radiopaque composites. X-ray images comparing with aluminum samples show that 15 wt.% barium sulfate (BaSO4) is sufficient to present radiopacity. Thermal studies by differential scanning calorimetry (DSC) show a statistically significant increase in PCL degree of crystallinity from 46% to 52% for 25 wt.% BaSO4. Non-isothermal crystallization tests were performed at different cooling rates to evaluate crystallization kinetics. The nucleation effect of BaSO4 was found to change the morphology and quantity of the primary crystals of PCL, which was also corroborated by the use of a polarized light optical microscope (PLOM). These results fit well with Avrami–Ozawa–Jeziorny model and show a secondary crystallization that contributes to an increase in crystal fraction with internal structure reorganization. The addition of barium sulfate particles in composite formulations with PCL improves stiffness but not strength for all compositions due to possible cavitation effects induced by debonding of reinforcement interphase.  相似文献   
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