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101.
《Journal of biomaterials science. Polymer edition》2013,24(6):509-516
Four different materials, low density polyethylene (LDPE), polydimethylsiloxane (PDMS), polyvinylcholoride (PVC) and cellulose, were selected by the Devices and Technology Branch of the National Heart Lung and Blood Institute (NHLBI) as primary reference materials for blood contacting. Among the wide variety of tests proposed to assess hemocompatibility of short-term blood contacting catheters, it was desirable to rule out whether these materials could release toxics for vascular cells of the physiological environment. Thus, the cytocompatibility of these materials have been checked towards human umbilical vein endothelial cells: the method used avoids direct contact between cells and materials but evaluates the effect of possible toxic substances leached from materials. These substances were obtained under defined conditions according to a standard. The results show that the extracts of cellulose and LDPE provoke an important cytotoxic effect on the endothelial cell cultures, while the extracts of PDMS and PVC allow the obtention of endothelial cell lining of the reference surface, with a correct global metabolic activity and the intracellular presence of von Willebrand factor. 相似文献
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A.A. Aro M.O. Perez C.P. Vieira M.A.M. Esquisatto R.A.F. Rodrigues L. Gomes E.R. Pimentel 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(2):428-435
In recent years, the scientific community has undertaken research on plant extracts, searching for compounds with pharmacological activities that can be used in diverse fields of medicine. Calendula officinalis L. is known to have antioxidant, anti‐inflammatory, antibacterial, and wound healing properties when used to treat skin burns. Therefore, the purpose of this study was to analyze the effects of C. officinalis on the initial phase of Achilles tendon healing. Wistar rats were separated in three groups: Calendula (Cal)—rats with a transected tendon were treated with topical applications of C. officinalis cream and then euthanized 7 days after injury; Control (C)—rats were treated with only vehicle after transection; and Normal (N)—rats without tenotomy. Higher concentrations of hydroxyproline (an indicator of total collagen) and non‐collagenous proteins were observed in the Cal group in relation to the C group. Zymography showed no difference in the amount of the isoforms of metalloproteinase‐2 and of metalloproteinase‐9, between C and Cal groups. Polarization microscopy images analysis showed that the Cal group presented a slightly higher birefringence compared with the C group. In sections of tendons stained with toluidine blue, the transected groups presented higher metachromasy as compared with the N group. Immunocytochemistry analysis for chondroitin‐6‐sulfate showed no difference between the C and Cal groups. In conclusion, the topical application of C. officinalis after tendon transection increases the concentrations of collagen and non‐collagenous proteins, as well as the collagen organization in the initial phase of healing. Anat Rec, 298:428–435, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
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目的 建立同时测定密蒙花药材中4种成分含量的方法,并进行主成分分析(principal component analysis,PCA)和偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)。方法 采用超高效液相色谱法,色谱柱为Waters ACQUITY UPLC BEH C18,流动相为乙腈-0.1%磷酸溶液(梯度洗脱),流速为0.15 mL/min,检测波长为330 nm,柱温为30 ℃,进样量为2 μL。采用SIMCA 14.1统计软件对含量测定结果进行PCA和PLS-DA研究。结果 4种指标性成分的线性、分离度、稳定性、重复性与精密度良好;24批药材样品有2个主成分,PLS-DA分析确定了2个分类标志物。结论 本研究建立的方法的精密度、稳定性、重复性均较好,可用于密蒙花药材中4种成分含量的同时测定;不同产地的密蒙花药材质量差异较大。 相似文献
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Aneesa Ansari Md.Shahed Zaman Shahriar Md.Mehedi Hassan Shukla Rani Das Begum Rokeya Md.Anwarul Haque Md.Enamul Haque Nirupam Biswas Tama Sarkar 《Asian Pacific journal of tropical medicine》2014,7(1):21-25
Objective:To evaluate the antidiabetic and antioxidant potential of Emblica officinalis(E.officinalis)fruit on normal and type 2 diabetic rats.Methods:Type 2 diabetes was induced into the male Long-Evans rats.The rats were divided into nine groups including control groups receiving water,type 2 diabetic controls,type 2 diabetic rats treated with glibenclamide(T2GT)and type 2diabetic rats treated with aqueous extract of fruit pulp of E.officinalis.They were fed orally for8 weeks with a single feeding.Blood was collected by cutting the tail tip on 0 and 28 days and by decapitation on 56 day.Packed red blood cells and serum were used for evaluating different biochemical parameters.Results:Four weeks administration of aqueous extract of E.officinalis improved oral glucose tolerance in type 2 rats and after 8 weeks it caused significant(P0.007)reduction in fasting serum glucose level compared to 0 day.Triglycerides decreased by 14%but there was no significant change in serum ALT,creatinine,cholesterol and insulin level in any group.Furthermore,reduced erythrocyte malondialdehyde level showed no significant change(P0.07)but reduced glutathione content was found to be increased significantly(P0.05).Conclusions:The aqueous extract of E.officinalis has a promising antidiabetic and antioxidant properties and may be considered for further clinical studies in drug development. 相似文献
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Carlos Granados-Echegoyen Rafael Pérez-Pacheco Marcos Soto-Hernndez Jaime Ruiz-Vega Luicita Lagunez-Rivera Nancy Alonso-Hernandez Rene Gato-Armas 《Asian Pacific journal of tropical medicine》2014,7(8):594-601
Objective:To determine larvicidal activity of the essential oil,hydrolat and botanical extracts derived from leaves ol Pseudocalymma alliaceum an mosquito larvae of Culex quinquefasciatus.Methods:Groups of twenty lanae were used in the larvicidal assays.The mortality,relative growth rate,the larval and pupal duration and viability was estimated.The essential oil was analyzed by solid phase microextraction using gas chromatography coupled to mass spectrometry.Results:Essential oil at 800 ppm showed larvicidal activity at 24 h with lethal values of LC_(50) and LC_(90) of 267.33 and 493.63 ppm.The hvdrolat at 20% and 10% on 2nd stage larvae showed 100%effectiveness after 24 h.The aqueous extract at 10% had a relative growth index of 0.58.while the ethanolic and methanolic extract obtained values of 0.76 and 0.70 and control reached 0.99.Larvae treated with 10% of methanol,ethanol and aqueous extract showed a reduction in larval duration of 5.00,2.20 and 4.35 days;ethanol extract at 1% provoke decrease of 2.40 days in the development and exhibited an increment of 3.30 days when treated with 0.01%.Aqueous,ethanol and methanol extracts at 10%reduced in 6.15,3.42 and 5.57 days pupal development.The main compounds were diallyl disulfide(50.05%),diallyl sulfide(11.77%) and disulfide di-2-propenyl(10.37%).Conclusions:The study demonstrated for the first time,the larvicidal activity of the essential oil and hydrolat of Pseudocalymma alliaceum:aqueous,ethanol and methanol extracts inhibited the normal growth and development of mosquito larvae,prolonging and delaying larval and pupal duration. 相似文献
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目的系统评价黑升麻提取物改善子宫内膜异位症患者术后促性腺激素释放激素激动剂(GnRHa)治疗导致低雌激素状态的有效性。方法计算机检索至2020年1月,在Medline、PubMed、Cochrane Library、中国期刊全文数据库(CNKI)、中国生物医学文献数据库、万方数据和维普中国科技期刊数据库中,检索子宫内膜异位症患者腹腔镜手术后GnRHa疗程中加入黑升麻提取物辅助治疗以缓解GnRHa造成的低雌激素状态的临床随机对照试验,对符合纳入标准的文献进行质量评价,使用Revman 5.3软件对数据进行meta分析。结果最终纳入7篇随机对照研究,总计745例患者。meta分析结果显示,与对照组比较,黑升麻提取物的加入不会影响患者体内激素水平,包括血清雌二醇水平( MD=1.24,95% CI:-4.58~7.08, P>0.05)和促黄体激素水平( MD=-0.02,95% CI:-0.15~0.11, P>0.05)。黑升麻提取物可以有效改善由于GnRHa造成患者体内低雌激素所产生的围绝经期症状:改善患者潮热出汗( OR=0.1,95% CI:0.02~0.47, P < 0.01),减少失眠症状的发生( OR=0.23,95% CI:0.13~0.39, P < 0.01),改善乏力( OR=0.09,95% CI:0.04~0.20, P < 0.01),减少阴道干燥的发生( OR=0.04,95% CI:0.01~0.30, P < 0.01)。黑升麻提取物的加入会影响手术12周后患者Kupperman绝经指数(KMI)评分( MD=-11.50,95% CI:-20.09~-2.90, P < 0.01)及24周后KMI评分( MD=-23.68,95% CI:-39.66~-7.69, P < 0.01)。 结论目前有限的证据表明,黑升麻提取物能够有效地改善子宫内膜异位症患者术后GnRHa治疗造成体内雌激素含量降低所引起的围绝经期症状,且不会影响体内激素水平。 相似文献
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《亚太热带病杂志(英文版)》2014,4(5):378-383
ObjectiveTo determine the total phenolics and flavonoids and to evaluate antioxidant and antimicrobial activities of different extracts from fruits of Datura metel (D. metel).MethodsDifferent crude extracts from the fruits of D. metel were subjected to determination of total phenolics, flavonoids, antioxidant and antimicrobial activities by established methods.ResutlsThe total phenolics results showed that ethyl acetate extract was the most efficient (60.26%) compared to hexane, chloroform, butanol and methanol extracts which had phenolic contents of 50.08, 35.50, 52.54 and 26.49%, respectively. Almost similar results were obtained from the fruits crude extracts for total flavonoids and results found that methanol crude extract was the highest (1.71%) compared to other crude extracts. The antioxidant activity results showed that methanol extract acted the highest activity compared to other extracts and in the order of methanol>ethyl acetate>hexane>chloroform>butanol extract. All extracts were displayed moderate antibacterial potential against the tested bacteria such as Staphylococcus aureus, Escherichia coli and Pseudomonus aeruginosa in the range of 0%–10%.ConclusionsThe results of this present study clearly showed that the crude extracts of D. metel demenstrated antimicrobial and antioxidant activities and it may act as potential antioxidant sources for human biological system. 相似文献