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目的 观察青蒿琥酯和熊果酸不同剂量和配伍对大鼠脂质代谢紊乱模型的影响,寻找青蒿琥酯和熊果酸配伍应用的最佳配比。方法 利用喂养高脂饲料诱导大鼠形成脂质代谢紊乱模型,通过比较各给药组大鼠的血脂水平筛选最佳配比。结果 实验结果显示,青蒿琥酯(高剂量)+熊果酸(高剂量)均有显著降低TG、CHO、LDL-C作用,可明显升高HDL-C,对H/L值也有一定的升高作用。综合降脂效果优于阳性药非诺贝特,也优于单用同等剂量的青蒿琥酯或熊果酸。各受试样品对大鼠肝功能没有显著影响(P>0.05,与正常组比较)。结论 青蒿琥酯和熊果酸1:1配比降脂效果最佳,建议剂量为(50+50) mg/kg。 相似文献
93.
Plant growth-promoting rhizobacteria (PGPR) not only promote growth and heavy metal uptake by plants but are promising biosorbents for heavy metals remediation. However, there exist arguments over whether extracellular adsorption (biosorption) or intracellular accumulation (bioaccumulation) play dominant roles in Cd(ii) adsorption. Therefore, three cadmium-resistant PGPR, Cupriavidus necator GX_5, Sphingomonas sp. GX_15, and Curtobacterium sp. GX_31 were used to study bioaccumulation and biosorption mechanisms under different initial Cd(ii) concentrations, using batch adsorption experiments, desorption experiments, scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) spectroscopy, transmission electron microscopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. In this study, with the increase of the initial Cd(ii) concentrations, the removal efficiency of strains decreased and the adsorption capacity improved. The highest Cd(ii) removal efficiency values were 25.05%, 53.88%, and 86.06% for GX_5, GX_15, and GX_31 with 20 mg l−1 of Cd(ii), while the maximum adsorption capacity values were 7.97, 17.13, and 26.43 mg g−1 of GX_5, GX_15, and GX_31 with 100 mg l−1 of Cd(ii). Meanwhile, the removal efficiency and adsorption capacity could be ordered as GX_31 > GX_15 > GX_5. The dominant adsorption mechanism for GX_5 was bioaccumulation (50.66–60.38%), while the dominant mechanisms for GX_15 and GX_31 were biosorptions (60.29–64.89% and 75.93–79.45%, respectively). The bioaccumulation and biosorption mechanisms were verified by SEM-EDX, TEM and FTIR spectroscopy. These investigations could provide a more comprehensive understanding of metal-bacteria sorption reactions as well as practical application in remediation of heavy metals.Plant growth-promoting rhizobacteria (PGPR) not only promote growth and heavy metal uptake by plants but are promising biosorbents for heavy metals remediation. 相似文献
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Rui Feng Yang Liu Shipu Li Hanbin Chen Chengyi Song Peng Tao Jianbo Wu Peng Zhang Tao Deng Wen Shang 《RSC advances》2018,8(72):41657
This paper presents the study on the hydrogen evolution reaction (HER) of the silicon nanowire (SiNW)-based surfaces. Large-area SiNWs with different lengths were fabricated on the silicon surfaces by a cost effective and scalable wet-etching method. The SiNW-based surfaces promoted the photoelectrocatalytical performance of the electrodes due to the increased effective surface area for electrolyte diffusion and the fast release of hydrogen bubbles that formed on the electrodes. In addition, at different applied potentials, the nanostructured electrodes showed different behaviour that depended on the SiNWs'' with different lengths and morphologies. For example, surfaces with longer SiNWs performed better in the low potential region, while surfaces with shorter SiNWs presented improved performance in the high potential region. The findings in this study provide new insights into designing electrodes with desired nanostructures for improved HER performance.This paper presents the study on the hydrogen evolution reaction (HER) of the silicon nanowire (SiNW)-based surfaces. 相似文献
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目的:本研究拟定量地比较Q开关和长脉宽1064 nm掺钕:钇-铝石榴石(neodymium-yttrium-aluminum garnet,Nd:YAG)激光诱导真皮胶原重建的疗效。方法:应用Q开关和长脉宽1064 nm Nd:YAG激光分别对36只雌性昆明小鼠左侧后背皮肤进行连续4次治疗,每次间隔1周,右侧相应的部位作为自身对照。分别于第1次治疗后1h、1天、7天、21天、30天和60天对小鼠皮肤行活组织取材。应用免疫组化方法分别对皮肤组织样品中真皮I、III型胶原进行检测,染色结果应用Motic医学数字图像分析系统进行定量分析。结果:与正常对照组相比,Q开关1064 nm Nd:YAG激光治疗后7天、21天、30天和60天,真皮I型胶原及III型胶原水平明显增高(均P0.01)。长脉宽1064 nm Nd:YAG激光治疗后21天、30天和60天,真皮I型胶原水平明显增高(均P0.01);激光治疗后7天、21天、30天和60天,真皮III型胶原水平明显增高(分别为P0.01、P0.05、P0.01、P0.01)。两组激光的比较:激光治疗后7天、21天和30天,Q开关1064nm Nd:YAG激光治疗组真皮I型胶原水平较长脉宽1064nm Nd:YAG激光治疗组明显增高(均P0.01),而激光治疗后60天明显降低(P0.05);激光治疗后7天和21天,Q开关1064nm Nd:YAG激光治疗组较长脉宽1064nm Nd:YAG激光治疗组真皮III型胶原水平明显增高(分别为P0.05、P0.01)。结论:Q开关和长脉宽1064nm Nd:YAG激光均可引起真皮胶原重建,但二者的作用效果不尽相同。 相似文献
99.
《Journal of pharmacological sciences》2019,139(4):377-384
Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterized by inflammation, multifocal fibrotic lesions and excessive collagen deposition with limited therapies. As a major bioactive compound in garlic, S-allyl-l-cysteine (SAC) is a neuroprotective drug candidate to prevent cognitive decline, however, its anti-pulmonary fibrotic activity remains unknown. Here, we investigated whether SAC could attenuate bleomycin (BLM)-induced pulmonary fibrosis and inflammation in mice. Our results showed that SAC dose-dependently reduced the infiltration of inflammatory cells, pulmonary lesions and collagen deposition in BLM treated mice with downregulated mRNA expression levels of fibrotic genes including alpha smooth muscle actin (α-SMA), fibronectin, collagen I and collagen III as well as the protein level of α-SMA. In addition, SAC could also reduce the mRNA expression of inflammatory mediators such as TNF-α and iNOS. Furthermore, higher phosphorylation of AKT and NF-κB p65 in IPF patient samples and murine samples was verified by immunohistochemistry while SAC could decrease the phosphorylation level of AKT and NF-κB p65 in mice stimulated with BLM. These findings, for the first time, indicate that SAC might mediate AKT/NF-κB signaling pathway to inhibit BLM-induced pulmonary fibrosis and support the potential role of SAC as an anti-pulmonary fibrosis agent. 相似文献
100.
文章介绍了一款自动化装置的结构设计基本方案,该装置可应用在基于图像的显微病理分析中,能够对体液样本进行离心处理,并在不移动样本的情况下直接降低转速,配合沿样本平台径向直线运动的物镜,对样本进行逐格扫描.为了避免离心运动过后转速降低使得样品恢复原始状态,本文还设计了一款特殊的样本容器.该设计中还提出了一种新型微调平机构解决方案,用以调节旋转平台基准面与聚光镜发出光线的垂直度.最后通过有限元仿真软件对该机构进行模态分析. 相似文献