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981.
Molecular Biology Reports - The soil nature and characterstics are directly related to the micro-organisms present, bio-mineralization process, plant type and thus having harmonius and...  相似文献   
982.
Tracer experiments have shown that in Papaver somniferum papaverine arises from (−)-norreticuline via norlaudanidine and norlaudanosine.  相似文献   
983.
Roseoside, a C13 glycoside isolated from Vinca rosea has been assigned the structure and stereochemistry (1).  相似文献   
984.
The second messenger molecules cAMP and Ca2+ regulate a large number of eukaryotic cellular events. cAMP acts on protein kinases and Ca2+ works through a ubiquitous calcium-binding protein, calmodulin. The two systems are not independent, however, but interact in several important fashions. These interactions, and, in particular, the modulation of the cAMP signal by two Ca2+/calmodulin-regulated proteins, cyclic nucleotide phosphodiesterase and calcineurin, are described here.  相似文献   
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987.
Decolorization of three triphenylmethane dyes by three bird's nest fungi—Cyathus bulleri, C. stercoreus, and C. striatus—was studied. Cyathus bulleri was found to be the most efficient in decolorization as demonstrated by the disappearance of the dyes from cultures, monitored by decreases in absorbance. Growth of the Cyathus spp. was not affected by the presence of dyes in the cultures. Decolorization of dyes was also observed with extracellular culture filtrates, indicating exocellular activity. Laccase activity, tested in replicate cultures, was found to be maximum during the decolorization period. Nitrogen in the medium had no effect on decolorization.  相似文献   
988.
Cinnamomum species have applications in the pharmaceutical and fragrance industry for wide biological and pharmaceutical activities. The present study investigates the chemical composition of the essential oils extracted from two species of Cinnamomum namely C. tamala and C. camphora. Chemical analysis showed E-cinnamyl acetate (56.14 %), E-cinnamaldehyde (20.15 %), and linalool (11.77 %) contributed as the major compounds of the 95.22 % of C. tamala leaves essential oil found rich in phenylpropanoids (76.96 %). C. camphora essential oil accounting for 93.57 % of the total oil composition was rich in 1,8-cineole (55.84 %), sabinene (14.37 %), and α-terpineol (10.49 %) making the oil abundant in oxygenated monoterpenes (70.63 %). Furthermore, the acetylcholinesterase inhibitory activity for both the essential oils was carried out using Ellman's colorimetric method. The acetylcholinesterase inhibitory potential at highest studied concentration of 1 mg/mL was observed to be 46.12±1.52 % for C. tamala and 53.61±2.66 % for C. camphora compared to the standard drug physostigmine (97.53±0.63 %) at 100 ng/ml. These multiple natural aromatic and fragrant characteristics with distinct chemical compositions offered by Cinnamon species provide varied benefits in the development of formulations that could be advantageous for the flavor and fragrance industry.  相似文献   
989.
Diffusion rate of the cationic solute through the porin pore was five times higher in the vesicles made of acidic phospholipids than in that of zwitterionic phospholipids. In contrast, diffusion of the anionic solute through these vesicles was reciprocally reversed. Diffusion ofpara-nitrophenyl phosphate was enhanced in the presence of lipopolysaccharide and the phospholipids extracted from bacterial cells as compared with the diffusion through porin in phosphatidyl choline.  相似文献   
990.
Previous investigations from our laboratory have demonstrated a significant reduction in the catalytic function of the 60 kDa and 63 kDa isozymes of calmodulin-dependent cyclic nucleotide phosphodiesterase (CaMPDE) when comparing human cerebral tissue that was free of tumor and glioblastoma multiforme (GBM) and gliosarcoma [Lal S., Raju R.V.S., Macaulay R.B.J., and Sharma R.K. (1996) Can. J. Neurol. Sci., 23, 245–250], The results suggested the possibility of an endogenously produced inhibitor of CaMPDE expressed in these tumors. Further investigation has initially characterized the presence of a heat-labile, protein inhibitor of both the 60 kDa and 63 kDa isozymes of CaMPDE. Sephacryl S-200 gel filtration column chromatography indicated that the inhibitor has an apparent molecular weight of 22 kDa and experimental evidence demonstrates that this inhibitor protein may act independently of calmodulin, and is therefore a novel CaMPDE inhibitor. Previous work on non-CNS tumors has shown high levels of CaMPDE activity and absence of an inhibitor. This suggests that a different mechanism may exist for the proliferation of these subsets of tumors.  相似文献   
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