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991.
Abstract

Combined chemo-photothermal therapy is attracting increasing attention in the treatment of cancers. In this work, PEGylated mesoporous SiO2-coated gold nanostars (GNS@mSiO2-PEG) were synthesised without using the cytotoxic surfactant cetyltrimethylammonium bromide as the template. Mesoporous nanostructures were obtained by poly(vinylpyrrolidone) protection of the outer silica shell and NaOH etching of the inner shell. GNS@mSiO2-PEG exhibited good dispersity in medium and excellent photothermal effects. Loading capacity for the anticancer drug doxorubicin (DOX) was ~17.9%, and the drug release profile was pH- and light-responsive. In vitro studies revealed that the as-prepared nanocomposites featured good biocompatibility. Furthermore, the nanocomposites were readily internalised by cancer cells, and a combined chemo-photothermal therapy assay revealed that DOX-loaded GNS@mSiO2-PEG have a higher therapeutic efficiency than individual therapies, demonstrating suitable synergistic effects.  相似文献   
992.
It was recently revealed thatRhynchophylline (Rhy), an important constituent of Uncaria rhynchophylla, possessed antihypertensive and neuroprotective effects. However, no information about the pharmacokinetics of Rhy in a herbivorous speciessuch as rabbit is available. Allometric scaling is valuable in designing human pharmacokinetic parameters from preclinical species. To investigate the characteristics of Rhy in vivo, a rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the measurement of Rhy concentrations in rabbit plasma. The method was linear over the concentration range of 0.01–10.24 µg/mL. Intra-day and inter-day precision and accuracy were less than 8.0%. The recoveries were in the range of 94.17%–103.32%. Matrix effects (ME) were minor. After oral administration of Rhy at 20, 40 and 80 mg/kg, the mean elimination half-life (t1/2) for these doses were 1.19, 1.49 and 1.37 h in rabbits, respectively. There was a proportionate increase in the maximum concentration (Cmax) and the area under the blood concentration-time curve (AUC) for three doses. The developed method was suitable for the study on pharmacokinetics of Rhy after oral administration and it may provide a valuable basis for clinical application of such a bioactive compound of herbal medicines.  相似文献   
993.
目的探讨补肾调经汤改善多囊卵巢综合征(PCOS)排卵状况的作用机制。方法选用80只雌性SD大鼠,建立PCOS大鼠模型,随机分为空白组、模型组、二甲双胍组、补肾调经汤高剂量组、低剂量组,每组10只,其余大鼠剔除。观察各组大鼠血清瘦素、胰岛素和睾酮激素的变化。结果补肾调经汤高剂量组、低剂量组均可以使PCOS大鼠血清瘦素、胰岛素、睾酮降低,补肾调经汤高剂量组与二甲双胍组在降低瘦素、胰岛素和睾酮水平方面作用相近。结论补肾调经汤可能通过对瘦素、胰岛素、睾酮的调节促进PCOS大鼠排卵。  相似文献   
994.
近年来,国内已有老年公寓尝试采用信息化手段完成对入住老人的健康管理,但是由于缺乏行业相关技术标准,各老年公寓健康管理信息化水平仍存在较大差异。本研究开发的老年公寓中医药健康管理系统包括具有中医特色的健康档案、实时动态的健康状态监测与评估以及中医知识库等。本文还介绍了系统功能与特色,系统具备技术架构先进、安全可靠等特点,可提升老年公寓入住人群的生存质量。  相似文献   
995.
黄振翘治疗再生障碍性贫血的经验   总被引:3,自引:0,他引:3  
黄振翘教授擅长运用中医药治疗再生障碍性贫血等疑难血液病 ,认为再障治疗宜掌握标本缓急 ;注重补肾泻肝 ;扶正不忘祛邪 ;强调整体治疗 ,临床取得了良好疗效。  相似文献   
996.

Objective

To investigate the influence of moxibustion products on mitochondrial transmembrane potential (MTP) and mRNA expression of Bax/Bcl-2 in alveolar type II epithelial A549 cells, and to further explore influence of moxibustion products on the oxidative damage of A549 cells.

Methods

Smoke and particles generated by moxibustion were collected using the filter box for gas sampling. The moxa smoke extract (MSE) was diluted sequentially to the final concentrations of 0.05 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL using the cell culture medium, and A549 cells were then intervened by the above MSE solution. Cell MTP was detected by JC-1 staining. Fluorescence quantitative polymerase chain reaction (PCR) was used to detect Bax/Bcl-2 mRNA expression of A549 cells.

Results

Compared with cells in the normal control group, MTP was significantly decreased in cells of 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.01); while MTP showed no significant changes in cells of 0.05 mg/mL, 0.1 mg/mL and 0.2 mg/mL MSE intervention groups (P>0.05); compared with cells in 0.05 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.05 ); compared with cells in 0.1 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.4 mg/mL MSE intervention group (P<0.01). Bax mRNA expression of cells in each concentration of MSE intervention group all showed no significant difference compared to that in the normal control group; Bcl-2 mRNA expression of cells was reduced with the increase of MSE intervention concentration. Wherein, Bcl-2 mRNA expressions of cells in 0.4 mg/mL and 0.3 mg/mL MSE intervention groups were significantly reduced compared with that of cells in the normal control group (P<0.05); Bcl-2 mRNA expression of cells in 0.4 mg/mL MSE intervention group was significantly reduced compared to that in 0.05 mg/mL MSE intervention group (P<0.05).

Conclusion

Certain higher concentration of moxa smoke could reduce MTP and mRNA expression of the anti-apoptosis gene Bcl-2 in alveolar type II epithelial A549 cells. Oxidative damage may be the important mechanism of apoptosis caused by the high concentration of moxa smoke solution, and further studies are necessary on the specific mechanisms.
  相似文献   
997.
目的探讨辅助性T淋巴细胞亚群Th1、Th2在慢性特发性血小板减少性紫癜(ITP)发病中的作用,观察生血灵对慢性ITP Th1、Th2亚群功能状态的影响。方法以酶联免疫吸附法(ELISA法)检测慢性ITP患者外周血单个核细胞(PBMC)培养上清中Th1型细胞因子IL-2和Th2型细胞因子IL-10的水平。结果慢性ITP患者PBMC培养上清中IL-2和IL-10的含量均较正常对照组明显减低(P均<0.001),生血灵对其具有明显提升作用(P<0.01)。结论慢性ITP患者Th亚群免疫功能低下。生血灵治疗慢性ITP能够增强Th亚群免疫功能,恢复其平衡。  相似文献   
998.
目的:研究人参多糖注射液对肿瘤的抑制作用及其对免疫功能的影响,并探讨其对环磷酰胺(CTX)化疗的增效减毒作用。方法:以S180瘤株ICR小鼠作为病理模型,随机分为模型组、未造模组、CTX组、联合用药组。连续给药10天后,测定其抑瘤率、白细胞数、胸腺指数和脾指数。同时复制CTX 致免疫低下小鼠模型,考察人参多糖注射液对血清溶血素和单核细胞吞噬功能的影响。结果:人参多糖注射液和CTX 合用时,能显著提高抑瘤率;同时减轻CTX 的毒副作用;对CTX 致免疫低下功能有一定的改善功能。结论:人参多糖注射液对CTX 具有明显的增效减毒作用。  相似文献   
999.
本研究尝试以数学关系式来描述中药药性与功效之间的关联,并建立数学模型。在此基础上,运用统计学进一步分析,总结中药的性-效关联规律。力求对药性理论进行现代阐释的同时,增加药性理论的确定性。  相似文献   
1000.
目的 :研究桂枝汤对体温双向调节作用与下丘脑PGE2 含量及COX活性的关系。方法 :采用放免法对下丘脑中PGE2 含量及COX活性进行同步检测。结果 :在酵母诱导发热大鼠中 ,桂枝汤可使下丘脑中PGE2 含量明显降低 (P <0 .0 5) ,而在安痛定诱导的低体温大鼠中 ,它可使PGE2 含量明显增高 (P <0 .0 5)。在两种模型中 ,桂枝汤对下丘脑细胞中COX活性的影响均不明显 (P >0 .0 5)。结论 :桂枝汤对体温的双向调节作用可能部分是通过影响PGE2 含量来实现的 ,但PGE2 含量增减不依赖于下丘脑细胞中COX活性的变化。  相似文献   
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