Publications by authors named "Yang-dong Li"

The 5α,6-dihydro congeners of veragranines A and B, two steroidal alkaloids with an unprecedented hexacyclic skeleton and potent analgesic effects, were synthesized from hecogenin acetate within six steps. This work enables quick access to the hexacyclic skeleton and is amendable to prepare other D-ring-modified congeners.

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The aim of the present study was to investigate the protective effects of Shenfu injection (SFI) against myocardial ischemia-reperfusion injury (MIRI) in model rats and to explore its mechanism of action. Sprague-Dawley (SD) rats were pretreated with SFI and N-nitro-L-arginine methyl ester (L-NAME) via tail vein injection and then rats were subjected to ischemia by occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion for 120 min. Left ventricular function was evaluated by echocardiography.

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Reactive oxidative compounds including superoxide anions and nitric oxide are believed to play a central role in many blinding eye diseases. In the present study, we examine the effect of ischemia on human retinal pigment epithelial (RPE) cells in an unusual clinical case. We show that ischemia leads to extensive nitrotyrosine deposition in the RPE and choroid, thus indicating NO-dependent oxidative stress.

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The human retina is rich in autofluorescent species, such as lipofuscin and melanin. Consequently, it is difficult to localize antigens in the human retina using immunofluorescence microscopy. To address this issue, we have developed a methodology to tag retinal antigens using quantum dot nanoparticles that absorb in the ultraviolet and emit in the infrared, thereby avoiding the visible spectrum.

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The pathogenicity of a field isolate of Marek's disease virus (MDV) named GXY2 integrated with retroviral long terminal repeat (LTR) sequence from a chicken with MD tumors was evaluated. Experimental chickens were divided into group A, B, C, D and E. The later four groups were vaccinated on one-day-old with CVI988/Rispens for group B and D, with HVT for group C and E, while group A was taken as no-vaccinated control.

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Aim: To prepare the compound danshen pH-dependent delayed release pellets and filled them in capsules and then study thier pharmacodynamics.

Methods: The pH-dependent delayed release pellets were prepared by coating with HPMC, Eudragit L-30D-55 and Eudragit L100-Eudragit S100 (1:6), separately, and mixed in proper proportion to prepare the two pH-dependent delayed release systems T1 and T2. The release of delayed release pellets was determined according to the method of China Pharmacopoeia (2000) in the simulated gastrointestinal pH conditions.

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