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摘 要 目的:建立苍耳子药材的HPLC特征图谱,为评价不同产地苍耳子的质量提供参考。方法: 采用Alltima C18(250 mm×4.6 mm,5 μm),流动相乙腈 0.1%磷酸溶液梯度洗脱,流速:0.8 ml·min-1,检测波长:278 nm,柱温:25 ℃,对来自河南、吉林、安徽等地共47批苍耳子样品运用“中药指纹图谱相似度评价系统”进行分析。 结果:以绿原酸为参照峰,初步构建了由5个特征峰组成的苍耳子HPLC 特征图谱。结论:该方法简便、可靠,为苍耳子药材的质量控制提供了有效的评价方法。  相似文献   
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The increase in multidrug resistance among colon cancer cells presents a challenge for the development of effective therapies. Small-molecule analogues of second mitochondria-derived activator of caspase (SMAC) mimetic in association with mixed lineage kinase domain-like protein (MLKL)-pDNA and z-VAD-fmk have shown ideal antitumor effects in colon cancer cells in vitro via induction of RIP3-dependent necroptosis. To achieve synergistic antitumor effects in vivo, liposomes loaded with SMAC mimetic, MLKL-pDNA and z-VAD-fmk have been developed using novel lipid fusion methods to co-localise the molecules of interest within the tumour cells. The co-encapsulation liposome (MLKL-zVAD-BV6-LP) had a high entrapment efficiency of approximately 95% for both zVAD and BV6 and was able to condense MLKL-pDNA very well. The vectors showed good biocompatibility, tumour targeting and small-molecule co-localisation. In a CT26 mouse model, the MLKL-zVAD-BV6-LP exhibited a tumour-suppression rate of over 60% in vivo, which was significantly higher than that of both the null-liposome and coadministration groups. Above all, the co-encapsulation system provided a novel approach to combination tumour therapy.  相似文献   
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Accurate and efficient antigen delivery is crucial for inducing a strong and long-term immune response. A visible protein nanovaccine made from antigen could provide a novel and promising technology for secure and efficient delivery of the antigen with imaging visualization. In this study, a functional nanovaccine based on genipin crosslinked ovalbumin (OVA) fluorescent nanoparticles with chitosan (CS-OVA-NPs) was developed. The nanovaccine can carry abundant antigens by self-crosslinking without additional carriers. The fluorescence imaging technique was applied to monitor and reveal the process of antigen delivery in vivo based on the fluorescence of genipin with a non-invasive and real-time manner. This functional OVA nanovaccine can enhance the uptake of OVA in Dendritic Cells (DCs) and further promote DCs to maturate in vitro. In vivo study further indicated CS-OVA-NPs could trigger antigen-specific immune responses, which demonstrated that this fluorescent nanovaccine provided a novel design approach for accurate and efficient vaccine delivery.  相似文献   
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This report describes the development of polyplexes based on CXCR4-inhibiting poly(ethylenimine) derivative (PEI-C) for pulmonary delivery of siRNA to silence plasminogen activator inhibitor-1 (siPAI-1) as a new combination treatment of pulmonary fibrosis (PF). Safety and delivery efficacy of the PEI-C/siPAI-1 polyplexes was investigated in vitro in primary lung fibroblasts isolated from mice with bleomycin-induced PF. Biodistribution analysis following intratracheal administration of fluorescently labeled polyplexes showed prolonged retention in the lungs. Treatment of mice with bleomycin-induced PF using the PEI-C/siPAI-1 polyplexes resulted in a significant down-regulation of the PAI-1 expression and decreased collagen deposition in the lung. The results of this study provide first evidence of the potential benefits of combined inhibition of CXCR4 and PAI-1 in the pulmonary treatment of PF.  相似文献   
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BackgroundThis study aimed to offer key features to differentiate scrub typhus (ST) and murine typhus (MT) at the early stage of the diseases and provide clinicoepidemiologic characteristics of ST and MT in southern Taiwan, a region where both diseases are endemic. Comparison of doxycycline treatment efficacy between the two diseases by matching disease severity and delayed treatment had never been investigated.MethodsWe reviewed the medical records of cases of ST and MT in four hospitals in southern Taiwan. Propensity-score matching was used to analyze the defervescence curves between patients with doxycycline-treated ST and MT by log-rank test.ResultsBetween 2004 and 2016, 265 ST and 63 MT cases were diagnosed. The number of cases of ST was significantly related to temperature (Rs = 0.77) and rainfall (Rs = 0.63). Island area exposure, arthropod bite, eschar, and lymphadenopathy were only recorded in ST patients. Multivariate analysis revealed that mountainous area exposure (odds ratio [OR], 11.0; 95% confidence interval [CI], 4.4–27.2) was an independent predictor for ST, while contact with rats (OR, 8.4; 95% CI, 3.3–21.3) was that for MT. After propensity-score matching, there was no difference in defervescence curves between these two rickettsioses treated with doxycycline (p = 0.24).ConclusionIn the present study, island area exposure, arthropod bite, eschar, and lymphadenopathy were unique manifestations of ST. Mountainous area exposure is a predictive factor for ST, while contact with rats predicted MT. There was no difference in defervescence time between these two rickettsioses after doxycycline treatment.  相似文献   
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目的探讨哮喘儿童外周血T细胞亚群表达极其在发病机制中的作用。方法10例健康儿童为对照组,15例确诊支气管哮喘的儿童为实验组。采用流式细胞术检测CD3^+、CD4^+、CD8^+T细胞百分数。结果实验组与对照组比较,经检验各组(P〉0.05),差异无显著性。结论哮喘发作1~3d内的患儿外周血中T细胞亚群水平表达与正常儿童无差异。  相似文献   
20.
The prognostic significance and clinical implications of resident CD103+CD8+T cells in human colorectal cancer tissues still remains largely unexplored. In our present study, we aimed to characterize the resident CD8+T cells in human colorectal cancer tissues by using double staining of CD103 and CD8, and further evaluated the prognostic significance of resident CD8+T cells in colorectal cancer. We found that the OS rate of the colorectal cancer patients with higher infiltration of CD8+T cells, or with higher numbers of resident CD103+CD8+T cells, or with higher ratio of CD103+CD8+T cells over total CD8+T cells in cancer tissues was significantly better than that of the patients with lower infiltration of CD8+T cells, or with lower numbers of resident CD103+CD8+T cells, or with higher ratio of CD103+CD8+T cells over total CD8+T cells in cancer tissues, respectively. Moreover, higher infiltration of CD8+T cells in colorectal cancer tissues was significantly and inversely correlated with advanced TNM stage. Higher numbers of resident CD103+CD8+T cells in colorectal cancer tissues were significantly and inversely correlated with distant metastasis status. Higher ratio of CD103+CD8+T cells over total CD8+T cells in colorectal cancer tissues was significantly and inversely correlated with age status. The COX model analysis demonstrated that higher infiltration of CD8+T cells, higher numbers of resident CD103+CD8+T cells, or higher ratio of CD103+CD8+T cells over total CD8+T cells in colorectal cancer tissues, could serve as independent prognostic predictors for colorectal cancer patients. Taken together, our present study demonstrated the density of tumor infiltrating CD8+T cells or the numbers of resident CD103+CD8+T cells in colorectal tissues could be used as an important prognostic predictor for this malignancy.  相似文献   
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