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81.
<正>Two new phenylethanoid glycosides,named scroside H(1),scroside I(2),and a new secoiridoid glycoside,named picrogentioside I(3),have been isolated from the underground parts of Picrorhiza scrophulariiflora.Their structures were elucidated on the basis of spectroscopic evidence.  相似文献   
82.
Porous silicon(PSi)was applied as a supporting substrate for stepwise covalent derivatization of undecylenic acid, N-hydroxysuccinimidyl ester(NHS-ester)and nitrilotriacetic acid(NTA).By taking the advantages of porous silicon as a supporting matrix such as high surface area to volume ratio,infrared transparency,porous semiconductors for laser desorption/ionization mass spectroscopy,and low fluorescence background,a multi-mode detection biochip prototype can be realized. We prepared such a protein microarra...  相似文献   
83.
A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry(LC-MS/MS) for the determination of glycyrrhetic acid in human plasma with ginsenoside Rh2 as internal standard was developed and validated. The plasma samples were prepared via liquid-liquid extraction with ethyl acetate. Chromatographic separation was accomplished on a Venusil MP-C18(50 mm×2.1 mm, 5 μm i.d.) column at 25 °C. The mobile phase consisted of acetonitrile/5 mmol?L-1 ammonium acetate(10:90, volume ratio) at a flow rate ...  相似文献   
84.
A mixture of oligosaccharide and glycopeptide was isolated from the aqueous extract of Panax ginseng roots. The mixture inhibits protein tyrosine phosphatase(SHP-1) function, implying it enhances immune activity. The peak molecular mass of the oligosaccharide portion is 1800 calculated via GPC software after separation by HPLC. And the structure of the oligosaccharide portion is the backbone of (1→3)-and (1→4)-linked arabinopyranoside, and (1→4)-and (1→6)-linked glucopyranoside, with non-reducing terminals ...  相似文献   
85.
直接合成性能优良的水溶性CdTe量子点,然后在其表面成功修饰花生凝集素,经过凝胶柱的分离纯化获得功能化的量子点荧光探针.基于T抗原选择性与花生凝集素(PNA)结合的特性,利用该探针对肠癌中高表达的T抗原进行检测,且与传统的荧光染料标记的免疫荧光分析进行了比较.实验结果表明:该功能化的荧光探针能够有效地识别肠癌的相关T抗原,从而为T抗原的检测以及肠癌的临床诊断与愈后判断提供了一种新的方法.  相似文献   
86.
首次利用微钻石衰减全反射傅里叶变换红外光谱法 (ATR/FTIR)研究了天敌惊恐对小鼠组织的损伤。结果表明 :惊恐后小鼠肾与足表面脂类化合物明显增高 ;服用补肾天然药物后 ,与正常对照组相比 ,脂类化合物变化不明显 ,进而说明药补可缓和压力 ,起到一定的调节作用。惊恐后小鼠心、肝和脑组织的红外谱没有变化 ,这是因为各个脏器对皮质激素的敏感程度不完全一样。  相似文献   
87.
讨论了引起统计蒸发模型计算结果与高温热核偶极巨共振实验结果之间存在差别的因素,对比了标准CASCADE程序计算结果与加入复杂粒子发射后的计算结果,计算显示复杂粒子发射对高温热核偶极巨共振的性质有影响.  相似文献   
88.
A novel terpenoid, named lappulanocarpine A 1 was isolated from the alcoholic extract of the whole plant of Lappula anocarpa. Its structure was characterized by I D-, 2D-NMR and HR-ESIMS.  相似文献   
89.
A new triterpenoid saponins, raddeanoside R19 (1) was isolated from the rhizome of Anemone raddeana Regel. The effects of raddeanoside R19 on superoxide generation in human neutrophil were evaluated. The compound suppressed the superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP), phorbol 12-myristate 13-acetate (PMA) and araehidonic acid (AA) in a different concentration-dependent manner.  相似文献   
90.
Citrinal A(1),a novel tricyclic compound with a rare tetrahydro-2H-benzofuro[7-b][1,4]dioxin-9(3H)-one skeleton,along with two known related compounds,citrinin(2) and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran(3) were isolated from an algicolous fungus Penicillium sp.i-1-1.The structure and stereochemistry of 1 were determined by comprehensive spectral and biogenic analysis.Its cytotoxic effects on the A-549 and HL-60 cell lines were evaluated.  相似文献   
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