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Baicalin Reduces Early Brain Injury after Subarachnoid Hemorrhage in Rats

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Chinese Journal of Integrative Medicine 2020年第7期26卷 510-518页

作者： ZHANG Hua-bin TU xian-kun SONG Shi-wei LIANG Ri-sheng SHI Song-sheng Department of Neurosurgery Fujian Medical University Union HospitalNeurosurgery Research Institute of Fujian ProvinceFuzhou(350001)China

Objective: To evaluate the effect of baicalin on subarachnoid hemorrhage(SAH) in rats and explore the potential mechanisms. Methods: Sprague-Dawley rats underwent experimental SAH and received treatment with baicalin at 10 or 50 mg/kg after 2 and 12 h of SAH. Neurological scores, brain water content, Evans-blue extravasation, and levels of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), myeloperoxidase(MPO), and malondialdehyde(MDA) were measured 24 h after SAH. Expression of nuclear factor erythroid-related factor 2(Nrf2), NAD(P)H: quinone oxidoreductase 1(NQO1), matrix metalloproteinase-9(MMP-9), aquaporin 4(AQP4), occludin, and zonulaoccludens-1(ZO-1) were detected in the brain by Western blot. Heme oxygenase-1(HO-1) was detected by quantitative polymerase chain reaction, and tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) were assessed by enzyme-linked immunosorbent assay. Results: Baicalin attenuated EBI 24 h after SAH in rats(P<0.05). Baicalin elevated neurological scores, GSH-Px, SOD, and increased the expression of Nrf2, NQO1, HO-1, occludin, and ZO-1 in SAH rats(P<0.05 or P<0.01). Baicalin reduced MPO, MDA, and the expression of MMP-9, AQP4, TNF-α, and IL-1β(P<0.05 or P<0.01). Conclusion: Baicalin reduced SAH-induced EBI, partially via activation of the Nrf2/HO-1 pathway and inhibition of MMP-9 and AQP4.

关键词： aquaporin 4 baicalin Chinese medicine early brain injury matrix metalloproteinase-9 subarachnoid hemorrhage

一种基于目标与背景特征分离模型的高光谱目标检测修正算法

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光谱学与光谱分析 2024年第1期44卷 283-291页

作者：吴护林邓贤明张天才李忠盛岑奕汪家辉熊杰陈知华林牧春中国兵器工业第五九研究所重庆401329 中国科学院空天信息创新研究院北京100101

高光谱图像立方体数据可以提供成像场景中地物在可见光和近红外波长范围内的空间信息和地物属性诊断的光谱特征信息,在目标检测与识别方面拥有得天独厚的天然优势。然而,基于高光谱图像数据的目标检测也存在一定缺陷,如经典的高光谱目... 详细信息

高光谱图像立方体数据可以提供成像场景中地物在可见光和近红外波长范围内的空间信息和地物属性诊断的光谱特征信息,在目标检测与识别方面拥有得天独厚的天然优势。然而,基于高光谱图像数据的目标检测也存在一定缺陷,如经典的高光谱目标检测算法仅利用光谱维度信息检测目标,检测模型要么对背景高维特征矩阵构建的准确度不足,要么对背景先验光谱特征的完备性要求较高,导致算法对不同复杂度的检测场景适应性不强。因此,基于计算复杂度较低、参数需求量较少且检测性能较为优异的经典多目标检测算法—多目标约束能量最小化(MCEM),提出了一种基于目标与背景环境特征分离模型的高光谱目标检测修正算法(R-MCEM)。首先,设计了一个与目标形状、尺寸相近的逐像元移动运算窗口,依次计算窗口中的每个像元与窗口内其他像元的光谱距离之和D1,像元与各类目标的光谱距离之和D2。其次,采用获得D1/D2最小值的像元替换窗口内的所有像元值。然后,自左向右、自上而下逐像元移动窗口,重复窗口内每一个像元与目标、背景像元的光谱距离运算,并确定窗口内与背景相似度最高、与目标相似度最低的像元。直到移动运算窗口遍历整个高光谱图像,大幅提升了基于目标与背景环境特征分离的背景高维特征矩阵准确度。分别设计了基于实测高光谱图像数据和模拟图像数据的修正检测算法性能验证试验,并采用三维操作特征曲线(3D ROC)结合目标与背景分离度(SDBT)开展修正算法的检测精度评估。试验结果表明,提出的修正算法有效减少了虚警率,提高了检测精度。基于实测数据的检测精度、目标与背景分离度由MCEM算法的0.937 7、 0.57提升到R-MCEM的0.993 5、 0.67,基于模拟数据的亚像元检测能力由MCEM的20%丰度提升到R-MCEM的15%丰度。

关键词：高光谱目标检测目标与背景特征分离模型 3D ROC SDBT

Existence of at Least Two Periodic Solutions of a Ratio-dependent Predator-prey Model with Exploited Term

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Acta Mathematicae Applicatae Sinica 2005年第3期21卷 489-494页

作者： De-sheng Tian xian-wu Zeng College of Mathematics and Statistics Wuhan University Wuhan 430072 China

In this paper, we study a non-autonomous ratio-dependent predator-prey model with exploited term. By means of the coincidence degree theory, we establish a sufficient condition for the existence of at least two positi... 详细信息

关键词： Predator-prey model ratio-dependent exploited term periodic solution coincidence degree

基于UPLC-QQQ-MS技术的仙灵脾颗粒体内药代动力学研究

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中南药学 2024年第4期22卷 930-936页

作者：王月鑫王帅杨欣欣李天娇赵琳包永睿孟宪生辽宁中医药大学药学院辽宁大连116600 辽宁省中药多维分析专业技术创新中心辽宁大连116600 辽宁省现代中药研究工程实验室辽宁大连116600

目的研究仙灵脾颗粒中主要成分在大鼠血浆内的药代动力学及整合药代动力学行为,以探讨其长期临床用药时间间隔的合理性。方法取12只雄性SD大鼠,随机分组后给予给药组大鼠仙灵脾颗粒8.1 g/(kg·d),连续给药7 d后,于给药前及给药后0.25... 详细信息

目的研究仙灵脾颗粒中主要成分在大鼠血浆内的药代动力学及整合药代动力学行为,以探讨其长期临床用药时间间隔的合理性。方法取12只雄性SD大鼠,随机分组后给予给药组大鼠仙灵脾颗粒8.1 g/(kg·d),连续给药7 d后,于给药前及给药后0.25、0.5、1、2、3、4、6、8、12 h大鼠眼眶后静脉丛取血0.5 mL,通过UPLC-QQQ-MS技术测定大鼠血浆内不同时间点淫羊藿属苷A、朝藿定A、朝藿定B、朝藿定C、淫羊藿苷、宝藿苷Ⅱ、淫羊藿次苷Ⅰ及宝藿苷Ⅰ的血药浓度,并分别赋予8个成分抗骨质疏松药效权重系数进行整合,采用DAS 3.2.8软件计算血浆药代动力学参数并得到血药浓度-时间曲线。结果大鼠连续多次给药后,8种成分在血浆内的药代动力学参数:t_(max)均为0.5 h,C_(max)为1.36~48.76ng·mL^(-1),t_(1/2)为8.50~81.40 h,AUC_(0~t)为14.52~138.19 ng·mL^(-1)·h,MRT_(0~t)为3.27~5.96 h;扣除0 h时间点血药浓度后所有成分在血浆内的药代动力学参数:t_(max)均为0.5 h,C_(max)为0.18~40.37 ng·mL^(-1),t_(1/2)为1.00~3.00 h,AUC_(0~t)为0.40~37.49 ng·mL^(-1)·h,MRT_(0~t)为1.51~4.41 h;8种成分赋予抗骨质疏松药效权重后,整合药代动力学参数:t_(max)=0.5h、t_(1/2)=(1.92±0.42)h。结论通过对仙灵脾颗粒血浆内药代动力学进行研究,阐明了其临床给药时间间隔的合理性,同时为仙灵脾颗粒抗骨质疏松药效物质基础研究提供依据及参考。

关键词：仙灵脾颗粒黄酮类 UPLC-QQQ-MS 药物代谢规律整合药代动力学

十种芳香南药精油抑制真菌生长和毒素累积的效果比较

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湖北农业科学 2024年第7期63卷 105-109页

作者：梁焕宴邱淑芳冼梦婷周亚奎赵祥升中国医学科学院药用植物研究所海南分所/海南省南药资源保护与开发重点实验室海口570311

研究香茅[Cymbopogon nardus(L.)Rendle]等10种芳香南药精油对黄曲霉菌(Aspergillus flavus)、黑曲霉菌(Aspergillus niger)生长和黄曲霉毒素B1、赭曲霉毒素A累积的抑制效果,以期将芳香南药精油开发为绿色、高效的杀菌剂。水蒸气蒸馏法... 详细信息

研究香茅[Cymbopogon nardus(L.)Rendle]等10种芳香南药精油对黄曲霉菌(Aspergillus flavus)、黑曲霉菌(Aspergillus niger)生长和黄曲霉毒素B1、赭曲霉毒素A累积的抑制效果,以期将芳香南药精油开发为绿色、高效的杀菌剂。水蒸气蒸馏法提取精油,熏蒸法研究精油对黄曲霉菌和黑曲霉菌的抑制作用,气相色谱-质谱法分析精油成分,超高效液相色谱法检测黄曲霉毒素B1和赭曲霉毒素A的含量。结果表明,10种精油的抑菌和抑制毒素累积作用存在较大差异。肉桂精油对黄曲霉菌、黑曲霉菌生长和毒素累积的抑制作用最强。香茅精油、大叶丁香精油、广藿香精油、降香精油对霉菌生长和毒素累积也有较强的抑制作用。益智精油、高良姜精油、白胡椒精油、莪术精油、沉香精油的抑菌效果不明显。甲基丁香酚、广藿香醇、柠檬醛、肉桂醛、反式橙花叔醇及其氧化物可能是发挥抗菌作用的成分。香茅、大叶丁香、广藿香、肉桂和降香精油具有开发为抑菌剂的潜力。

关键词：芳香南药精油抑制能力黄曲霉菌黑曲霉菌真菌毒素

Steel Slag as an Iron Fertilizer for Corn Growth and Soil Improvement in a Pot Experiment

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Pedosphere 2006年第4期16卷 519-524页

作者： WANG xian CAI Qing-sheng College of Life Sciences Nanjing Agricultural University Nanjing 210095 （China） Department of Biology Zhoukou Normal College Zhoukou 366000 （China）

The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that moderate rates (10 and 20 g kg-1) of slag or acidified slag substantially increased corn dry matter yield and Fe uptake. Application of steel slag increased the residual concentration of ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extractable Fe in the soils. The increase of extractable Fe was usually proportional to the application rate, and enhanced by the acidification of slag. Steel slag appeared to be a promising and inexpensive source of Fe to alleviate crop Fe chlorosis in Fe-deficient calcareous soils.

关键词： corn growth iron fertilizer pot experiment soil improvement steel slag

The mechanism and relevant mediators associated with neuronal apoptosis and potential therapeutic targets in subarachnoid hemorrhage

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Neural Regeneration Research 2023年第2期18卷 244-252页

作者： Qi Tian sheng Liu Shou-meng Han Wei Zhang xian-Yao Qin Jun-Hui Chen Cheng-Li Liu Yu-Jia Guo Ming-Chang Li Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal *** previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this *** them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after *** apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative ***,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal *** there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of *** this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH.

关键词： blood-brain barrier mechanism mediators neuronal apoptosis pathways subarachnoid hemorrhage targets treatment

Steric Hindrance Ligand Strategy to Aluminum Porphyrin Catalyst for Completely Alternative Copolymerization of CO_2 and Propylene Oxide

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Chinese Journal of Polymer Science 2018年第2期36卷 252-260页

作者： Chun-Wei Zhuo Yu-sheng Qin xian-Hong Wang Fo-Song Wang Key Laboratory of Polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

Aluminum porphyrin complexes are heavy-metal-free and soil-tolerant green catalysts for the copolymerization of CO2 and propylene oxide（PO）, but they suffer from relatively poor poly（propylene carbonate）（PPC） selectivity. Herein, steric hindrance porphyrin ligand was used to enhance the PPC selectivity. Typically, a bulky anthracene-like group was incorporated into the porphyrin ring to form 5,10,15,20-tetra（1,2,3,4,5,6,7,8-octahydro-1,4：5,8-dimethanoanthracen-9-yl）porphyrin, the aluminum porphyrin complex with this ligand, in combination with bis（triphenylphosphine）iminium chloride as a co-catalyst, produced completely alternate PPC. Additionally, the obtained PPC showed high regioselectivity, with a head-to-tail linkage content（HT） of 92%. Therefore, we demonstrated that introduction of bulky steric ligand into the porphyrin ring could reduce the propylene oxide homopolymerization activity leading to excellent PPC selectivity, and improve regioselectivity for the PO ring-opening during the copolymerization.

关键词： Carbon dioxide Propylene oxide Porphyrin Aluminum Steric hindrance

Application of Wox2a in transformation of recalcitrant maizegenotypes

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aBIOTECH 2023年第4期4卷 386-388页

作者： Qiangbo Liu xian sheng Zhang Ying Hua Su National Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai’an 271018China

The genetic transformation plays an important role in plant gene functional analysis and its geneticimprovement. However, only a limited number of maize germplasms can be routinely transformed. Themaize gene Wuschel-like homeobox protein 2a (Wox2a) was shown to play a crucial role in promotingthe formation of embryonic cells and enhancing the efficiency of genetic transformation in maize. Thiscommentary discusses the mechanism by which the Wox2a gene contributes to the variation inembryogenic tissue culture response among different maize inbred lines. In addition, the frequency andintensity of Wox2a or Wus2/Bbm vector-induced somatic embryogenesis was also discussed. Theapplication of Wox2a in transformation of recalcitrant maize genotypes could well accelerate thedevelopment of maize genetic improvement.

关键词： Genetic transformation Maize Wox2a Recalcitrant maize genotypes