The ability of vitamin E to prevent or treat experimental lead intoxication was investigated in rats.Lead ingestion(10 mg/kg,lead as lead acetate,orally fbr 6 weeks)significantly inhibited the activity of blood δ-ami...The ability of vitamin E to prevent or treat experimental lead intoxication was investigated in rats.Lead ingestion(10 mg/kg,lead as lead acetate,orally fbr 6 weeks)significantly inhibited the activity of blood δ-aminolevulinic acid dehydratase(ALAD),reduced the brain dopamine (DA)contents,enhanced the blood zinc protoporphyrin,and enhanced the urinary excretion of δ-aminolevulinic acid(ALA).Lead exposure also elevated brain norepinephrine,homovanillic acid,and 5-hydroxyindole acetic acid(5-HIAA)levels and concentration of lead in blood and tissue.Simultaneous supplementation of vitamin E along with lead significantly reduced the inhibition of blood ALAD activity,brain DA and 5-HIAA levels,and elevation of urinary ALA excretion.Blood and liver lead concentrations were also significantly reduced by simultaneous supplementation with vitamin E.Postlead exposure treatment with vitamin E was ineffective in reducing the lead-induced effects,except that the inhibition of blood ALAD activity was slightly reduced.The present results suggest that vitamin E given simultaneously with lead is effective in reducing the severity of lead intoxication.1989 Academic Press.Inc.展开更多
The cryosphere constitutes an important subset of the hydrosphere. The Himalayan cryosphere is a significant contributor to the hydrological budget of a large river system such as the Ganges. Basic data on the cryosph...The cryosphere constitutes an important subset of the hydrosphere. The Himalayan cryosphere is a significant contributor to the hydrological budget of a large river system such as the Ganges. Basic data on the cryosphere in the Himalaya is inadequate and also has large uncertainties. The data on glacial melt component in the Himalayan rivers of India also shows high variability. The Gangotri glacier which constitutes nearly a fifth of the glacierized area of the Bhagirathi basin represents one of the fastest receding, large valley glaciers in the region which has been surveyed and monitored for over sixty years. The availability of measurement over a long period and relatively small glacier-fed basin for the Bha- girathi river provides suitable constraints for the measurement of the glacial melt fraction in a Himalayan river. Pre- and post-monsoon samples reveal a decreasing trend of depletion of 0180 in the river water from glacier snout (Gaumukh) to the confluence of the Bhagiratbi river with the Alaknanda river near Devprayag. Calculations of existing glacial melt fraction (-30% at Rishikesh) are not consistent with the reported glacial thinning rates. It is contended that the choice of unsuitable end-members in the three component mixing model causes the overestimation of glacial melt component in the river discharge. Careful selection of end members provides results (-11% at Devprayag) that are consistent with the expected thinning rates.展开更多
The influence of vitamin E supplementation on the ability of α-mercapto-β(2-furyl)acrylic acid (MFA) or calcium trisodium dicthylenetriamine pentaacetate (DTPA) to reduce body burden of cadmium and reverse Cd-induce...The influence of vitamin E supplementation on the ability of α-mercapto-β(2-furyl)acrylic acid (MFA) or calcium trisodium dicthylenetriamine pentaacetate (DTPA) to reduce body burden of cadmium and reverse Cd-induced biochemical alterations was investigated in Cd-exposed rats. The treatment with MFA-vitamin E or CaNa3 DTPAvitandn E was more effective than either vitamin E or chelating agent alone, in depleting blood and tissue Cd. However, the combined treatment showed only limited advantage over the individuals in restoring Cd-induced biochemical changes. Further, the treatment with chelator-vitamin E concomitantly with the exposure to Cd was more effective than post-Cd exposure treatment.展开更多
Every river basin is characterised by an evolutionary history,which may be analysed at different time scales.This study provides a geological and geomorphic history of different river basins of India at different time...Every river basin is characterised by an evolutionary history,which may be analysed at different time scales.This study provides a geological and geomorphic history of different river basins of India at different time scales ranging from millions of years to millennial time scales.The river basins in India are divided into six different groups on the basis of different tectono-climatic settings and geomorphic characteristics.The evolutionary trajectories in the past strongly govern the modern day geomorphic characteristics and processes in a river basin.The basin scale data compiled in this paper highlights the role of geological inheritance and‘landscape memory’in the evolution of river systems of India.展开更多
文摘The ability of vitamin E to prevent or treat experimental lead intoxication was investigated in rats.Lead ingestion(10 mg/kg,lead as lead acetate,orally fbr 6 weeks)significantly inhibited the activity of blood δ-aminolevulinic acid dehydratase(ALAD),reduced the brain dopamine (DA)contents,enhanced the blood zinc protoporphyrin,and enhanced the urinary excretion of δ-aminolevulinic acid(ALA).Lead exposure also elevated brain norepinephrine,homovanillic acid,and 5-hydroxyindole acetic acid(5-HIAA)levels and concentration of lead in blood and tissue.Simultaneous supplementation of vitamin E along with lead significantly reduced the inhibition of blood ALAD activity,brain DA and 5-HIAA levels,and elevation of urinary ALA excretion.Blood and liver lead concentrations were also significantly reduced by simultaneous supplementation with vitamin E.Postlead exposure treatment with vitamin E was ineffective in reducing the lead-induced effects,except that the inhibition of blood ALAD activity was slightly reduced.The present results suggest that vitamin E given simultaneously with lead is effective in reducing the severity of lead intoxication.1989 Academic Press.Inc.
基金Science and Engineering Research Board,Department of Science and Technology,Government of India is acknowledged for funds for the project entitled"Finger printing of glacial melt water in the Ganga basin-implications for modeling of hydrological cycle in a Himalayan river system"grant number NO.SR/DGH-46/2012 which supported work for this paper
文摘The cryosphere constitutes an important subset of the hydrosphere. The Himalayan cryosphere is a significant contributor to the hydrological budget of a large river system such as the Ganges. Basic data on the cryosphere in the Himalaya is inadequate and also has large uncertainties. The data on glacial melt component in the Himalayan rivers of India also shows high variability. The Gangotri glacier which constitutes nearly a fifth of the glacierized area of the Bhagirathi basin represents one of the fastest receding, large valley glaciers in the region which has been surveyed and monitored for over sixty years. The availability of measurement over a long period and relatively small glacier-fed basin for the Bha- girathi river provides suitable constraints for the measurement of the glacial melt fraction in a Himalayan river. Pre- and post-monsoon samples reveal a decreasing trend of depletion of 0180 in the river water from glacier snout (Gaumukh) to the confluence of the Bhagiratbi river with the Alaknanda river near Devprayag. Calculations of existing glacial melt fraction (-30% at Rishikesh) are not consistent with the reported glacial thinning rates. It is contended that the choice of unsuitable end-members in the three component mixing model causes the overestimation of glacial melt component in the river discharge. Careful selection of end members provides results (-11% at Devprayag) that are consistent with the expected thinning rates.
文摘The influence of vitamin E supplementation on the ability of α-mercapto-β(2-furyl)acrylic acid (MFA) or calcium trisodium dicthylenetriamine pentaacetate (DTPA) to reduce body burden of cadmium and reverse Cd-induced biochemical alterations was investigated in Cd-exposed rats. The treatment with MFA-vitamin E or CaNa3 DTPAvitandn E was more effective than either vitamin E or chelating agent alone, in depleting blood and tissue Cd. However, the combined treatment showed only limited advantage over the individuals in restoring Cd-induced biochemical changes. Further, the treatment with chelator-vitamin E concomitantly with the exposure to Cd was more effective than post-Cd exposure treatment.
基金supported by COFUND fellowship at Durham University,UKSonam was supported by PhD fellowship provided by CSIR-UGC,India(Fellowship No.061320507-23/06/2013(i)EU-V).
文摘Every river basin is characterised by an evolutionary history,which may be analysed at different time scales.This study provides a geological and geomorphic history of different river basins of India at different time scales ranging from millions of years to millennial time scales.The river basins in India are divided into six different groups on the basis of different tectono-climatic settings and geomorphic characteristics.The evolutionary trajectories in the past strongly govern the modern day geomorphic characteristics and processes in a river basin.The basin scale data compiled in this paper highlights the role of geological inheritance and‘landscape memory’in the evolution of river systems of India.