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71.
Suresh Babu G. Farooq M. Ray R. S. Joshi P. C. Viswanathan P. N. Hans R. K. 《Water, air, and soil pollution》2003,144(1-4):149-157
Organochlorine pesticides were used earlier for agricultureproduction. Their residues may still be present in soil and mayaccumulate in food crops, posing potential health problems to consumers. DDT, HCH, their isomers and metabolites were analyzedin samples of soil and rice plants collected from ten differentvillages of a well-known Basmati rice growing area in Dehradun.Residues of both pesticides were found in all samples ofsoil and different parts of rice plants except for a few grainsamples. Maximum residue was observed in husk and minimum ingrains. The average concentration of DDT in soil ranged from0.013 to 0.238 ppm. p,p′-DDE was the major metabolite (>63%). Theaverage concentration of DDT in rice grain varied from 0.002 to 0.040 ppm. o,p′-DDT was the main isomer (>93%). Theaverage concentration of HCH in soil ranged from 0.122 to 0.638 ppm. β-HCH was the predominant (43%) isomerfollowed by α-HCH (21%). The average HCH concentrationin rice grain ranged between 0.013 and 0.113 ppm. All four isomers were present in grains. The levels of DDT and CHCin grains were similar in magnitude as those from differentIndian states, but well below the maximum residue limit of 0.1 ppm for DDT and 0.05 ppm for HCH prescribed by the Government ofIndia and WHO/FAO. As such, the pesticide residue levels in thisexport commodity are not of hazardous nature. 相似文献
72.
73.
Raghavan M Glickman N McCabe G Lantz G Glickman LT 《Journal of the American Animal Hospital Association》2004,40(3):192-203
A nested case-control study was conducted among 1634 dogs with complete diet information in a 5-year prospective study to determine diet-related risk factors for gastric dilatation-volvulus (GDV). Cases included 106 dogs that developed GDV; controls included 212 dogs without GDV that were frequency matched to cases by year of GDV onset. Proportionate energy consumed from major food types and from carbohydrates was determined. Dogs were categorized as consuming either a low volume or high volume of food based on the median number of cups of food fed per kg of body weight per meal. Dogs fed a larger volume of food per meal were at a significantly (P<0.05) increased risk of GDV, regardless of the number of meals fed daily. For both large- and giant-breed dogs, the risk of GDV was highest for dogs fed a larger volume of food once daily. 相似文献
74.
The hexane extract of Phyllanthus maderaspatensis (200 and 100 mg/kg) showed significant hepatoprotection on carbon tetrachloride and thioacetamide induced liver damage in rats. The protective effect was evident from serum biochemical parameters and histopathological analysis. Rats treated with P. maderaspatensis remarkably prevented the elevation of serum AST, ALT and LDH and liver lipid peroxides in CCl(4) and thioacetamide treated rats. Hepatic glutathione levels significantly increased by the treatment with the extracts. Histopathological changes induced by CCl(4) and thioacetamide were also significantly reduced by the extract treatment. The activity of hexane extracts of P. maderaspatensis was comparable to that of silymarin, the reference hepatoprotective drug. 相似文献
75.
A 60% azadirachtin-A concentrate has been obtained through repeated precipitation with hexane from a methanolic solution of a 20% concentrate. Azadirachtin-A (90%) has been obtained by medium-pressure liquid chromatography of the 60% concentrate with an RP-18 column and a methanol + water (1 + 1 by volume) solvent system. Catalytic hydrogenation of the 60 and 90% azadirachtin concentrates yielded the corresponding tetrahydroazadirachtin concentrates. Dihydroazadirachtin and tetrahydroazadirachtin formed during the first 5 h of hydrogenation were identified by LC-ESI-MS on the basis of their unique mass fragmentation pattern. The efficacy of tetrahydroazadirachtin concentrates in inhibiting the feeding and growth of Helicoverpa armigera (Hübner) larvae has been compared with that of azadirachtin concentrates. They were in general more active and deterred larvae from feeding at all concentrations. Tetrahydroazadirachtin-A (90%) and azadirachtin-A (90%) with respective IC(50) values of 280 and 390 mg L(-1) were effective as insect growth regulators, while tetrahydroazadirachtin-A (90%) displayed higher antifeedant activity (AI(50) 14 mg L(-1)) against the test insect. 相似文献
76.
Uttarani Maibam Sohan Vir Singh Anil Kumar Singh Suresh Kumar Ramesh Chandra Upadhyay 《Tropical animal health and production》2014,46(7):1155-1160
To evaluate difference in the expression of skin color genes (melanocortin 1 receptor (MC1R) and premelanosome (PMEL)) in lymphocytes during winter and summer season and their correlation with tyrosinase enzyme and cortisol, ten Karan-Fries heifers were selected from National Dairy Research Institute (NDRI) cattle farm. Blood samples were collected from the animals during winter (THI?=?60) and summer (THI?=?83) season at weekly intervals. Relative MC1R and PMEL messenger RNA (mRNA) expression of Karan Fries cattle was found to be significantly (P?0.01) higher during winter than summer. Similarly, tyrosinase activity during winter was found to be significantly (P?0.01) higher than summer season. However, plasma cortisol level was significantly (P?0.01) higher during summer than winter. Thus, expression of the skin color genes showed positive correlation with tyrosinase enzyme, but negative correlation with cortisol level. Expression of MC1R and PMEL in lymphocytes and tyrosinase activity of Karan Fries cattle was highly reduced during summer. The present study showed that the ability of Karan Fries cattle to protect themselves from the harmful radiation of sunlight by melanization decreased with increased heat stress on them. 相似文献
77.
Viruses alter the structure and the function of mitochondria for survival. Electron microscopy analysis of the cells infected with bovine adenovirus 3 revealed extensive damage to the inner mitochondrial membrane characterized by dissolution of the cristae and amorphous appearance of mitochondrial matrix with little or no damage to the outer mitochondrial membrane. There were fewer cristae with altered morphology. Potential patches of protein synthesis machinary around mitochondria could be observed at 12 hours post infection (hpi). At 24 hpi, the multi vascular bodies were evident throughout the infected cell. ATP production, mitochondrial Ca2+ and mitochondrial membrane potential (MMP) peaked at 18 hpi but decreased significantly at 24 hpi. This decrease coincided with the increased production of superoxide (SO) and reactive oxygen species (ROS), at 24 hpi indicating acute oxidative stress in the cells and suggesting a complete failure of the cellular homeostatic machinary. The results reveal an intericate relationship between Ca2+ homeostasis, the ATP generation ability of cells, SO and ROS production, and regulation of MMP following infection by bovine adenovirus 3. 相似文献
78.
Kimchi-Sarfaty C Oh JM Kim IW Sauna ZE Calcagno AM Ambudkar SV Gottesman MM 《Science (New York, N.Y.)》2007,315(5811):525-528
Synonymous single-nucleotide polymorphisms (SNPs) do not produce altered coding sequences, and therefore they are not expected to change the function of the protein in which they occur. We report that a synonymous SNP in the Multidrug Resistance 1 (MDR1) gene, part of a haplotype previously linked to altered function of the MDR1 gene product P-glycoprotein (P-gp), nonetheless results in P-gp with altered drug and inhibitor interactions. Similar mRNA and protein levels, but altered conformations, were found for wild-type and polymorphic P-gp. We hypothesize that the presence of a rare codon, marked by the synonymous polymorphism, affects the timing of cotranslational folding and insertion of P-gp into the membrane, thereby altering the structure of substrate and inhibitor interaction sites. 相似文献
79.
B. Rajasekaran D. Michael Warren Suresh Chandra Babu 《Agriculture and Human Values》1994,11(2-3):159-167
Farmer participatory approaches were used to identify problems and needs as perceived by local people and to develop strategies to achieve fodder security in south Indian villages. Indigenous knowledge systems as they relate to agroforestry were explored. The farmer participatory approaches have laid the foundations for selecting appropriate agroforestry technologies and developing suitable fodder security policy options. Potential benefits and risks as a result of implementing agroforestry projects were also discussed. 相似文献
80.
Raghavan V 《Science (New York, N.Y.)》1976,191(4225):388-389
When anthers of henbane containing uninucleate pollen grains were cultured, a large number of embryoids originated exclusively from the division of the generative cell. In a small proportion of pollen grains, both generative and vegetative cells contributed to embryoid formation. Embryogenesis by segmentation of the vegetative cell alone was rarely observed. 相似文献