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B. S. Shyamala P. V. Ananthalakshmi V. J. T. Raju P. Nagaraja Rao P. U. M. Reddy 《Biometals》1992,5(1):23-27
Metal complexes of divalent cobalt, nickel and copper and trivalent iron were synthesized usingN-salicylidene-3-aminocoumarin as chelating agent. The ligand behaves as a monobasic ONO donor towards Co(II), Ni(II) and Cu(II) and as an ON as well as an ONO donor towards Fe(III). All the complexes haven been proposed to have octahedral geometry on the basis of analytical, thermal conductivity, spectral and magnetic data. The complexes have been screened againstSpodoptera litura;F (Lepidoptera: noctuiidae) for antifeeding and insect-growth-regulating activity. The results show appreciable insect-growth-regulating activity associated with metal complexation. 相似文献
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Aerobiology, diversity and chemistry of some air borne plant trichomes were studied at Magadh University campus, Bodh Gaya, India between September 1995 and August 1996. Thirty-three morphotypes of trichomes were tapped using a Gravity Air sampler. The different types of trichomes showed pronounced seasonality in their distribution pattern. The simple non-septate trichomes of grasses were predominant throughout the year. The other commonly observed trichomes were comparable to that of Chrysanthemum, Tridax, Solanum, Amaranthus and Martynia. Trichomes. The Shannon diversity index of trichomes fluctuated widely (1.063–2.867) during different months of the year. This suggests that seasonality had definite bearing on the composition of aerobiota. Relative humidity was found to play greater role in the case of a number of morphotypes (67%), diversity index (50%) and species richness (61%) but in the case of index of dominance (62%), rainfall played a greater role at P < 0.01 level. The trichomes of a few selected plant species, the pollen grains of which are reported allergens, were chemically analysed by collecting them in bulk. They were found to be fairly rich in their total protein (9.58 to 93.60 mg/g) and carbohydrate (10.0 to 20.20 mg/g) contents. 相似文献
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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