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991.
The 1:1 condensation of 1,2-diaminopropane and 1-phenylbutane-1,3-dione at high dilution gives a mixture of two positional isomers of terdentate mono-condensed Schiff bases 6-amino-3-methyl-1-phenyl-4-aza-2-hepten-1-one (HAMPAH) and 6-amino-3,5-dimethyl-1-phenyl-4-aza-2-hexen-1-one (HADPAH). The mixture of the terdentate ligands has been used for further condensation with pyridine-2-carboxaldehyde or 2-acetylpyridine to obtain the unsymmetrical tetradentate Schiff base ligands. The tetradentate Schiff bases are then allowed to react with the methanol solution of copper(II) and nickel(II) perchlorate separately. The X-ray diffraction confirms the structures of two of the complexes and shows that the condensation site of the diamine with 1-phenylbutane-1,3-dione is the same. 相似文献
992.
S K Chattopadhyay P K Taskar O Schwabe Y T Das H D Brown 《Cancer biochemistry biophysics》1985,8(1):67-75
Aflatoxin carcinogenesis appears to relate to multiple factors. This includes bulky adduct formation at DNA guanine N-7. The process also requires more extensive physiological degradation, possibly by the toxin alone as the active principle, but in instances also involving other assaults (e.g., hepatitis B virus). Since aflatoxin carcinogenesis involves complex effects, we have undertaken to define the range of influence of this common food contaminant upon a susceptible model, the broiler-type chick. Aflatoxicosis in two treated groups was indicated by jaundice, coagulopathy, dehydration of combs and shanks, retardation of body weight, and decrease in bursa weight. Blood clotting time, hemoglobin content, erythrocyte and packed-cell volume were affected. Hepatocytes were swollen and had undergone fatty degeneration. Bile duct hyperplasia was evident. Total serum protein, alkaline phosphatase, creatine, lactate dehydrogenase, serum glutamic oxalacetic transaminase and glutamyl transpeptidase were similarly abnormal in birds receiving the contaminated (0.5 and 2.5 micrograms/g aflatoxin B1) feed rations. The aflatoxin B1 and its metabolites were isolated by HPLC from chick serum, liver and muscle. 相似文献
993.
Effects of different water salinity levels on the decomposition of the two organic manures cowdung and poultry manure were studied under laboratory condition. Application of the manures increased the free CO2 content and decreased D.O. levels of water. pH values of soil and water declined slightly on addition of the manures. The amount of nitrogen, released from the organic manures to water and soil phases, increased gradually with the period of incubation but decreased with increase in water salinity levels. NH4
+ was found to occur in comparatively higher amount than NO3
–, due to prevailing anaerobic environmental conditions. The amount of added organic carbon remaining in the soil decreased gradually as the decomposition proceeded, but recorded slightly higher values with increase in water salinity levels.The results showed that the rates of decomposition of added organic manures were comparatively lower under higher water salinity levels and hence indicated that use of well decomposed manures might be more suitable for use under such water salinities in brackish water fish ponds.This work formed a part of a thesis submitted for the Degree of Doctor of Philosophy to Bidhan Chandra Agricultural University, West Bengal in 1978This work formed a part of a thesis submitted for the Degree of Doctor of Philosophy to Bidhan Chandra Agricultural University, West Bengal in 1978 相似文献
994.
In view of the predominance of acidic pH levels in lateritic soils and of the importance of this soil property on growth and
distribution of blue-green algae or cyanobacteria (CB), the effect of lime application on the reduction of acidity and subsequently
on growth and some related physiological properties of CB have been studied. Four soils with varying pH levels were used for
this purpose and three lime treatments corresponding to 0,50 and 100% lime requirement were applied to each of them. The soils
thus treated were incubated under submerged condition in an illuminated chamber for 6 weeks and were drawn at weekly intervals
for studies of the number, fresh mass and chlorophyll content of the developed algal mass. Increase of the pH value of the
soil through application of lime improved growth and relevant physiological properties of the CB. 相似文献
995.
Maintenance of membrane fluidity in Antarctic bacteria 总被引:1,自引:0,他引:1