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1.
These ligands (L) show a bidentate behavior, forming octahedral ruthenium complexes. The title complexes were subjected to in-vivo anticancer activity tests against a transplantable murine tumor cell line, Ehrlich's Ascitic Carcinoma (EAC) and in-vitro antibacterial activity against several Gram positive and Gram negative bacterial strains. [Ru(bpy)2(ihqs)]Cl2 and [Ru(bpy)2 (hc)]Cl2 (where bpy = 2,2'-bipyridine, ihqs = 7-iodo-8hydroxy quinoline-5-sulphonic acid and hc = 3-hydroxy coumarin) showed promising antitumor activity. Treatment with these complexes prolonged the life span of EAC bearing mice as well as decreased their tumor volume and viable ascitic cell count. All the tested complexes exhibited mild to moderate antibacterial activity.  相似文献   
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Chitinase, capable of degrading the cell walls of invading phytopathogenic fungi, plays an important role in plant defense response, particularly when this enzyme is overexpressed through genetic engineering. In the present study, Brassica plant (Brassica juncea L.) was transformed with chitinase gene tagged with an overexpressing promoter 35 S CaMV. The putative transgenics were assayed for their inhibitory activity against Alternaria brassicae, the inducer of Alternaria leaf spot of Brassica both in vitro and under polyhouse conditions. In in vitro fungal growth inhibition assays, chitinase inhibited the fungal colony size by 12-56% over the non-trangenic control. The bioassay under artificial epiphytotic conditions revealed the delay in the onset of disease as well as reduced lesion number and size in 35S-chitinase Brassica as compared to the untransformed control plants.  相似文献   
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The effect of exposure to sub-lethal concentrations of cypermethrin, a synthetic pyrethroid pesticide, on biochemical parameters of muscle, blood and enzyme activities in brain, liver and kidney of the Indian major carp, Labeo rohita was studied. The sub-lethal exposure studies were done for up to 45 days at 1/10 and 1/50 of 96 h LC(50) of cypermethrin. The 96 h LC(50) was found to be 0.139 ppm. RNA levels decreased while DNA levels were elevated. Acid phosphatase was unchanged while alkaline phosphatase was depleted. Brain acetylcholinesterase activity was decreased significantly (P<0.05) over a period of 45 days at both cypermethrin concentrations. Lactate dehydrogenase activity in brain and liver was elevated, but inhibited in kidney. Succinate dehydrogenase and ATPase activities were depleted in brain, kidney and liver. There was a decrease in serum protein level over control at both concentrations of the pyrethroid. Blood glucose level and total leucocytes were elevated compared with controls at either concentration from day 15 to day 45. Haemoglobin percentage and total erythrocytes decreased in both sub-lethal concentrations. Extracts of the herb Datura stramonium were effective in countering the toxicity of this pesticide. Our data suggest that sub-lethal exposure of cypermethrin alters the biochemical, haematological parameters and enzymes of organs tissue and exert stress on the fish. Plant extracts may be useful in counteracting some of these effects.  相似文献   
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An integrated genetic linkage map of the medicinal and ornamental plant Catharanthus roseus, based on different types of molecular and morphological markers was constructed, using a F2 population of 144 plants. The map defines 14 linkage groups (LGs) and consists of 131 marker loci, including 125 molecular DNA markers (76 RAPD, 3 RAPD combinations; 7 ISSR; 2 EST-SSR from Medicago truncatula and 37 other PCR based DNA markers), selected from a total of 472 primers or primer pairs, and six morphological markers (stem pigmentation, leaf lamina pigmentation and shape, leaf petiole and pod size, and petal colour). The total map length is 1131.9 cM (centiMorgans), giving an average map length and distance between two markers equal to 80.9 cM and 8.6 cM, respectively. The morphological markers/genes were found linked with nearest molecular or morphological markers at distances varying from 0.7 to 11.4 cM. Linkage was observed between the morphological markers concerned with lamina shape and petiole size of leaf on LG1 and leaf, stem and petiole pigmentation and pod size on LG8. This is the first genetic linkage map of C. roseus.  相似文献   
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A series of biarylsulfonamides was identified as hCCR2 receptor antagonist but suffered from high plasma protein binding resulting in a >100 fold shift in activity in a functional GTPγS assay run in tandem in the presence and absence of human serum albumin. Introduction of an aryl amide with ethylenediamine linker led to compounds with reduced shifts and improved activity in whole blood.  相似文献   
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Enantiomerically pure (S)-atenolol was prepared by using (R,R) salen Co(III) complex for the resolution of terminal epoxide. This process was carried out at room temperature in excellent enantio selectivity. The method can be applied for large-scale preparation of (S)-atenolol without any problem.  相似文献   
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A series of mononuclear Ru(II) complexes of the type [Ru(M)2(U)]2+, where M = 2,2'-bipyridine/1,10-phenanthroline and U = tpl (Ru1), 4-Cl-tpl (Ru2), 4-CH3-tpl (Ru3), 4-CH3O-tpl (Ru4), and 4-NO2-tpl (Ru5), -pai (Ru6), where tpl = thiopicolinanilide and pai = 2-phenyl-azo-imidazole, have been prepared and characterized by IR, UV-Vis, 1H NMR, 13C-NMR, FAB-Mass spectrophotometer, and elemental analysis. The complexes display metal-ligand charge transfer (MLCT) transitions in the visible region. The title complexes were subjected to in vivo anticancer activity tests against a transplantable murine tumor cell line, Ehrlich's ascitic carcinoma (EAC) and in vitro antibacterial activity against Gram positive and Gram negative microorganisms. Ru1-Ru6 were found to increase the life span of the tumor hosts by 19-52%, and decreased tumor volume and viable ascitic cell count. The results of the present study clearly demonstrated the tumor inhibitory activity of the ruthenium chelates against transplantable murine tumor cell line. The treatment with ruthenium complexes could be secondary to tumor regression or due to the action of the compounds itself. The significant antibacterial activity was observed for Ru1-Ru4 against microorganisms like Vibrio cholera 865, Staphylococcus aureus 6571, and Shigella flexneri as compared to that of standard drug chloramphenical. Ru5 showed moderate activity against S. aureus 8530. However, all the complexes fail to show significant antibacterial activity against V. cholera 14033 and Shigella sonnai.  相似文献   
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Silk moths are the best studied silk secreting insects and belong to the families Bombycidae and Saturniidae. The phylogenetic relationship between eleven silk producing insects was analyzed using the complete DNA sequence of the internal transcribed spacer DNA 1 locus. The PCR amplification and sequence analysis showed variation in length ranging from 138 bp (Antheraea polyphemus) to 911 bp (Hyalopora cecropia). Microsatellite sequences were found and was be used to distinguish Saturniidae and Bombycidae members. The nucleotide sequences were aligned manually and used for construction of phylogenetic trees based on Maximum parsimony and Maximum likelihood methods. The topology in both the approaches yielded a similar tree that supports the ancestral position of the Antheraea assama.  相似文献   
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