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81.
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The chemical analysis of the neutral extracts of Satureia calamintha and S. graeca aerial parts afforded, besides calaminthadiol, a new triterpene, isocalaminthadiol which belongs to the 3,4-seco-12-ursene class. The isolation of isocalaminthadiol and calaminthadiol may constitute a valid index for the chemotaxonomic characterization of the genus Satureia.  相似文献   
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The first two examples of naturally occurring C-glucosyl-α-hydroxydihydrochalcones have been isolated from Eysenhardtia polystachya, a Mexica  相似文献   
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Abstract

The genus Amanita Pers. ex Fr. in Rome neighbourood. — The presence of the genus Amanita in Rome neighbourood, small district, with vegetation and soil diversified, has been studied. The list includes 30 entities (A. caesarea, A. argentea°, A. nivalis, A. vaginata, A. vaginata var. cinerea°, A. fulva, A. crocea°, A. umbrinolutea°, A. lividapallescens°, A. strangulata, A. junquillea, A. eliae°, A. muscaria, A. pantherina, A. alba, A. phalloides, A. phalloides var. alba, A. verna, A. virosa, A. citrina, A. citrina var. alba°, A. porphyria°, A. rubescens, A. spissa. A. excelsa, A. aspera, A. vittadini, A. codinae°, A. strobiliformis, A. boudieri°), 11 new also for latium (°), among these A. codinae and A. vaginata var. cinerea hitherto not found in Italy. At last, the genus in whole region is examined.  相似文献   
85.
A method of monitoring slow rotational motions of proteins from the decay of the intrinsic phosphorescence is described. The phosphorescence is excited with a 10-μsec pulse of vertically polarized light from an air gap lamp, and the anisotropy was computed as a function of time from the simultaneously detected vertically and horizontally polarized components of the emission. The approach is illustrated with time-dependent measurements of the anisotropy of the tryptophan phosphorescence of Staphylococcus aureus nuclease, bovine carbonic anhydrase, and liver alcohol dehydrogenase in glycerol-phosphate buffer between ?90 and ?70°C. The temperature- and molecular-weight dependence of the exponential decays in the anisotropy indicate that overall rotation of the proteins is at the origin of the depolarization. The potential of the approach as a probe of the slow rotational motions of proteins in membranes and other macromolecular complexes is stressed.  相似文献   
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Molecular imaging of cell-mediated cancer immunotherapy   总被引:2,自引:0,他引:2  
New strategies based on the activation of a patient's immune response are being sought to complement present conventional exogenous cancer therapies. Elucidating the trafficking pathways of immune cells in vivo, together with their migratory properties in relation to their differentiation and activation status, is useful for understanding how the immune system interacts with cancer. Methods based on tissue sampling to monitor immune responses are inadequate for repeatedly characterizing the responses of the immune system in different organs. A solution to this problem might come from molecular and cellular imaging - a branch of biomedical sciences that combines biotechnology and imaging methods to characterize, in vivo, the molecular and cellular processes involved in normal and pathologic states. The general concepts of noninvasive imaging of targeted cells as well as the technology and probes applied to cell-mediated cancer immunotherapy imaging are outlined in this review.  相似文献   
89.
(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK.  相似文献   
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