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71.
目的:研究中药露蜂房中蛋白成份抗白血病作用的机理,为中药露蜂房治疗白血病的临床应用和开发新的抗白血病药物提供实验和理论依据。方法:采用细胞培养和透射电子显微镜技术,观察中药露蜂房蛋白成份对人红白血病细胞(K562细胞)的生长抑制作用和形态结构的影响,采用免疫组织化学方法测定露蜂房蛋白对K562细胞凋亡相关信号转导蛋白NF-κBp65、β-catenin及iNOS表达的影响。结果:(1)与生理盐水对照组比较,露蜂房蛋白处理组白血病细胞生长饱和密度降低,细胞增殖活性减弱(P<0.05);(2)露蜂房蛋白处理组白血病细胞呈典型的凋亡形态学改变;(3)与生理盐水对照组比较,露蜂房蛋白处理组白血病细胞中NF-κBp65、β-catenin及iNOS表达减弱,NF—κBp65和β-catenin细胞核内转导减少(P<0.05)。结论:中药露蜂房蛋白成份有明显抑制K562细胞的作用,其作用机制可能是通过调节凋亡相关信号传导因子NF-κBp65、β-catenin及iNOS的表达,从而诱导白血病细胞凋亡。  相似文献   
72.
目的 研究桦褐孔菌Inonotus obliquus水提物的毒理学性质,探究其是否具有相关生理和生殖毒性。方法 急性毒性试验,ICR小鼠,一次ig给予桦褐孔菌水提物1.00、2.00、3.00、4.00、5.00 g/kg,连续观察14 d。30 d喂养试验,Wistar大鼠,每次ig给予桦褐孔菌水提物1.50、2.00、2.50 g/kg,连续给药30 d。小鼠精子畸形试验,ICR雄性小鼠,每次ig给予桦褐孔菌水提物1.00、2.50、5.00 g/kg,连续给药5 d,给药后第35天颈椎脱臼法处死实验小鼠,取双侧附睾制片,染色,统计精子畸形率。结果 急性毒性试验,实验组小鼠给药30 min后,静伏少动,背毛竖立,出现腹泻症状,无动物死亡,实验动物24 h后恢复正常。30 d喂养试验,受试动物体质量和食物利用率与对照组相比差异不显著。脏器系数、血常规和血液生化相关指标也在正常范围内波动。病理学检查未发现组织器官的明显病变。小鼠精子畸形试验,所有实验组的精子畸形率均显著低于环磷酰胺处理的阳性对照组,桦褐孔菌水提物5.00 g/kg组小鼠精子畸形率较对照组有上升趋势。结论 桦褐孔菌水提物未表现出明显的生理毒性,但在高剂量时可能具有一定的生殖毒性。  相似文献   
73.
目的评价丹皮酚与银杏叶提取物1∶1组合物对大鼠脑缺血再灌注损伤的保护作用。方法尼莫地平(10.8 mg/kg)组、丹皮酚(37.5 mg/kg)组、银杏叶提取物(37.5 mg/kg)组以及丹皮酚银杏叶提取物1∶1组合物(75.0 mg/kg)组大鼠灌胃给予相应药物,给药容积10 m L/kg,ig给药6 d后大脑中动脉栓塞造模,脑缺血再灌注后4、24 h进行观察,计算行为学评分;动物取脑,测定脑梗死面积,计算脑梗死率;大鼠脑缺血再灌注后24 h后,测定血清中自由基超氧化物歧化酶(SOD)、丙二醛(MDA)、γ-氨基丁酸(GABA)、谷氨酸(Glu)水平和脑组织中基质金属蛋白酶-9(MMP-9)、GABA、Glu含量。结果与模型组比较,脑缺血再灌注22 h后,各组大鼠行为学评分均有降低趋势,其中组合物组的降低作用的差异具有显著性(P0.05);与模型组比较,脑缺血再灌注24 h后,银杏叶提取物、丹皮酚、组合物组大鼠脑梗死率均明显降低,差异具有显著性(P0.01);与模型组比较,组合物组大鼠血清中SOD水平、丹皮酚和组合物组血清中GABA水平显著升高(P0.05),银杏叶提取物、丹皮酚、组合物组大鼠血清中MDA水平、组合物组血清中Glu水平显著降低(P0.01、0.05);丹皮酚和组合物组大鼠脑组织中MMP-9、Glu含量显著降低(P0.01、0.05),组合物组脑组织中GABA含量显著升高(P0.01)。结论丹皮酚银杏叶提取物组合物对大鼠脑缺血再灌注损伤具有保护作用,其作用机制可能是通过抗氧化损伤、平衡兴奋性氨基酸与抑制性氨基酸浓度、调节MMP-9表达量有关。  相似文献   
74.
目的 筛选白藤梨根体外抗肿瘤作用部位并测定总三萜含量。方法 采用RTCA DP实时细胞分析系统研究白藤梨根提取物对人肺癌A549细胞和人肝癌HepG2细胞体外增殖的抑制作用,筛选其抗肿瘤作用的活性部位;并通过紫外分光光度法测定白藤梨根活性部位中总三萜的含量。结果 白藤梨根各提取物对人肺癌A549细胞和人肝癌HepG2细胞均有一定的抑制作用,其中白藤梨根石油醚部位、乙酸乙酯部位和乙醇部位对人肺癌A549细胞的IC50值分别为2,0.15,3.8 mg·mL-1,对人肝癌HepG2细胞的IC50值分别为75,7.6,71 μg·mL-1;紫外分光光度法测得白藤梨根乙酸乙酯提取物中总三萜含量高达45%。结论 白藤梨根体外抗人肺癌细胞和人肝癌细胞的主要部位为乙酸乙酯部位,其中总三萜为其主要抗肿瘤成分。  相似文献   
75.
Background:Radiation dermatitis is a common complication in patients with nasopharyngeal carcinoma (NPC) when treated with radiotherapy. Plant extracts have good effects on the prevention of radiation dermatitis in patients with NPC when treated with radiotherapy. However, there is insufficient comparison among the currently used plant extracts. Therefore, the purpose of this study was to explore the efficacy of different plant extracts in the prevention of radiation dermatitis in patients with NPC by Bayesian network meta-analysis.Methods:We searched Chinese and English databases to collect all randomized controlled trials (RCT) of plant extracts for the prevention of radiation dermatitis in NPC patients who underwent radiotherapy up to October 2020. Two researchers then independently screened articles, extracted data and evaluated the quality selected literatures. All data were processed by Stata 14.0 and WinBUGS V.1.4.3.Results:We applied Bayesian statistical model for network meta-analysis, ranked the effects of various plant extracts, and adopted GRADE method to explain the results.Conclusion:Our study is expected to provide high-quality evidence-based medicine advice for the prevention of radiation dermatitis in patients suffering from NPC undergoing radiotherapy.Ethics and dissemination:Ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and will be shared on social media platforms. This review would be disseminated in a peer-reviewed journal or conference presentations.OSF REGISTRATION NUMBER:DOI 10.17605/OSF.IO/6SV45.  相似文献   
76.
77.
《Journal of endodontics》2019,45(6):706-715
IntroductionAlginate/gelatin hydrogel (Alg-Gel) scaffold has been applied in tissue engineering, but the research on its application in dental tissues regeneration is still lacking. We investigated the effect of this scaffold on human dental pulp stem cells (hDPSCs).MethodshDPSCs were cultured in both Alg-Gel and 3D-printed Alg-Gel scaffolds. Cell growth and adhesion were compared using fluorescein isothiocyanate–phalloidin staining and scanning electron microscopic micrographs. Changes in the proliferation in hDPSCs cultured in the complete culture medium containing aqueous extracts of the Alg-Gel or 3D-printed Alg-Gel scaffolds were examined using Cell Counting Kit-8 assay and flow cytometry analysis. Cells were cultured in the mineralization medium containing aqueous extracts of the Alg-Gel or 3D-printed Alg-Gel scaffolds for 7 or 14 days, and the differentiation of cells was shown by alizarin red S staining and alkaline phosphatase staining. The messenger RNA and protein expression of mineralization-related genes were detected with real-time polymerase chain reaction and Western blotting. Elemental analysis was used to test the material extract composition.ResultsMore cells were grown and adhered to the 3D-printed Alg-Gel scaffolds than the Alg-Gel scaffolds. The aqueous extracts of 3D-printed scaffolds can promote cell proliferation, and compared with Alg-Gel scaffolds, the extracts of 3D-printed scaffolds were more effective. Compared with the negative control group, 3D-printed Alg-Gel scaffold and Alg-Gel scaffold aqueous extracts promoted osteogenic/odontoblastic differentiation of hDPSCs with the enhanced formation of bone-like nodules and the alkaline phosphatase staining. The expression of mineralization-related genes was also up-regulated. 3D-printed scaffold aqueous extract contained more calcium and phosphorus ions than the Alg-Gel scaffold.ConclusionsThese findings suggest that compared with the Alg-Gel scaffold, 3D-printed Alg-Gel is more suitable for the growth of hDPSCs, and the scaffold extracts can better promote cell proliferation and differentiation.  相似文献   
78.

Background

Radix Scutellariae, a few papers reported its pharmacology activities including alleviate small intestines smooth muscles spasm, sedation, antihypertensive effect. However, the inhibition of its different organic extracts on immediate hypersensitivity has not bee researched.

Materials and Methods

To investigate the anti-immediate hypersensitivity of three extracts including ethanol extracts, acetone extracts, ethyl acetate extracts from Radix Scutellariae, four pharmacological screening model were chose, such as 4-Aminopyridine induced pruritus model, histamine-induced mouse paw edema model, PCA(passive cutaneous anaphylaxis) in ear of mouse, activie cutaneous anaphylaxismouse (mouse ear edema test), furthermore, total IgE level in the sensitized mice serum was evaluated deeply.

Results

Ethanol group at 1.42g/kg and 0.71g/kg could greatly decrease the licking number to 1.2 and 12.7 respectively; also keep mice paw swelling at 0.29ml and 0.51ml at 15 min after injection of histamine. Both ear passive cutaneous allergic reaction and active cutaneous anaphylaxis-ear swelling test demonstrated that ethanol group exhibit great inhibition on immediate hypersensitivity.Low IgE level was found in ethanol group, but high in other two groups.

Conclusion

The ethanol extracts exhibits obvious strong inhibition, however, the acetone ones and ethyl acetate showed a little.  相似文献   
79.
目的:观察五倍子水提取物对人牙髓细胞Ⅰ型胶原合成的影响。方法:取第6代体外培养的人牙髓细胞分别与终末浓度为5、10μg/m L的五倍子水提取物共同培养3 d后,采用免疫组化染色法观察人牙髓细胞中Ⅰ型胶原的表达情况,并用HPIAS-1000图像分析系统进行定量分析。结果:对照组和不同浓度五倍子水提取物作用的实验组人牙髓细胞中均有Ⅰ型胶原的表达,其免疫反应物质多定位于胞浆。人牙髓细胞经5、10μg/m L浓度的五倍子水提取物作用后,其Ⅰ型胶原的表达水平均明显增高,其中以10μg/m L组的增高程度最大,各组间两两相比差异均有统计学意义(P<0.05)。结论:5、10μg/m L五倍子水提取物均能明显促进人牙髓细胞中Ⅰ型胶原的表达;提示其具有促进牙髓细胞向成牙本质细胞分化的作用。  相似文献   
80.
An efficient and eco-friendly protocol for the synthesis of bioactive silver nanoparticles was developed using Naringi crenulata leaf extracts via microwave irradiation method. Silver nanoparticles were synthesized by treating N. crenulata leaf extracts with 1 mM of aqueous silver nitrate solution. An effective bioactive compound such as alkaloids, phenols, saponins and quinines present in the N. crenulata reduces the Ag+ into Ag0. The synthesized silver nanoparticles were monitored by UV–vis spectrophotometer and further characterized by X-ray diffraction (XRD), Fourier Transform Infra Red (FTIR), Energy-dispersive X-ray spectroscopy (EDX) and field emission scanning electron microscopy (FESEM). UV–vis spectroscopy showed maximum absorbance at 390 nm due to surface plasmon resonance of AgNPs. From FESEM results, an average crystal size of the synthesized nanoparticle was 72–98 nm. FT-IR results showed sharp absorption peaks and they were assigned to phosphine, alkyl halides and sulfonate groups. Silver nanoparticles synthesized were generally found to be spherical and cubic shape. Topical application of ointment prepared from silver nanoparticles of N. crenulata were formulated and evaluated in vivo using the excision wound healing model on Wistar albino rats. The measurement of the wound areas was performed on 3rd, 6th, 9th, 12th and 15th days and the percentage of wound closures was calculated accordingly. By the 15th day, the ointment base containing 5% (w/w) of silver nanoparticles showed 100% wound healing activity compared with that of the reference as well as control bases. The results strongly suggested that the batch C ointment containing silver nanaoparticles synthesized from the leaf extracts of N. crenulata was found to be very effective in wound repair and encourages harnessing the potentials of the plant biomolecules loaded silver nanoparticle in the treatment of tropical diseases including wound healing.  相似文献   
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