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231.
The in vivo toxic effect of trivalent and hexavalent chromium (25 mg/L) on the renal and hepatic tissue ATPases of an edible teleost Anabas scandens was studied. In an exposure span of 30 days Na+-K+ ATPase activity exhibited a progressive inhibition in the kidney, but marked inhibition in Na+-K+ ATPase activity was observed in the liver. Mg2+ ATPase activity, however, exhibited an elevation on early exposures, with a later inhibition. 相似文献
232.
The influence of methyl farnesoate (MF) on testicular growth in the fresh water crab Oziotelplusa senex senex was studied. MF stimulated testicular growth as evidenced by increased testicular weight, testicular index and testicular
follicle diameter in MF injected crabs and provides evidence that MF acts as a male reproductive hormone in crustacea.
Received: 25 August 1998 / Accepted: 18 February 1999 相似文献
233.
Prasenjit Mondal A. Rama Narsimha Reddy Gadapa Swarnamanju Ramakrishna Raparla 《毒物与环境化学》2015,97(5):515-525
A novel, sensitive, and rapid UV spectrophotometric and colorimetric method was developed for estimation of etizolam (ETZ) in bulk and tablet. The UV spectrophotometric method (method I) is based on quantitative estimation of ETZ using 0.1N NaOH as the solvent which exhibits maximal absorption at 378 nm. Colorimetric methods (method II and III) were based on the formation of color complex in association with ions between basic nitrogen of the drug with methyl orange (MO) and bromocresol green (BCG) in acidic medium. The formed color complexes were quantitatively extracted with chloroform and measured at 509 nm for Drug–MO complex and at 442 nm for Drug–BCG complex, respectively. Beer's law was obeyed over the linear ranges 2–16 µg/ml (method I), 5–45 µg/ml (method II), and 2–20 µg/ml (method III). The correlation coefficient (r2) for ETZ was 0.999, 0.997, and 0.998 for method I, II, and III, respectively. All methods were successfully applied for the assay of the drug in tablet. The % purity was found to be 98.52 (method I), 98.72 (method II), and 99.18 (method III). These developed methods were fully validated with % relative standard deviation (RSD) for accuracy less than 2 for all methods. The % RSD of the intra-day and inter-day variations was found to be less than 2%. The limit of detection and quantitation were as follows: 0.108 µg/ml and 0.327 µg/ml (method I), 0.24 µg/ml and 0.75 µg/ml (method II), 0.1 µg/ml and 0.5 µg/ml (method III) indicating marked method sensitivity. Empirical evidence from all three methods concludes that developed methods are simple, sensitive, and reliably validated for useful routine quality control analysis of ETZ. 相似文献
234.
Malladi Srinivas Reddy Ramakrishna Saini Sudheer Kumar Dontamalla B. Suhasini 《毒物与环境化学》2015,97(7):839-846
A three-component one-pot protocol has been investigated for the synthesis of imidazo[4,5-f]indol-7-yl)indolin-2-ones from the commercially available materials. Structures of these compounds were established on the basis of IR, 1H NMR, and mass spectral data. The title compounds were evaluated for their antimicrobial activity. Two compounds exhibited the potent antimicrobial activity. 相似文献
235.
The present study was undertaken to evaluate the effect of sub-chronic exposure to benzo(a)pyrene on the antioxidant system and histology of rat epididymal sperm. Intraperitoneal administration of benzo(a)pyrene to male Wistar rats at doses between 1 and 100 µg/kg body weight for 60 days entailed a decrease in the weight of the epididymis (caput and cauda), seminal vesicle, and prostate, while the body weight was not affected. Epididymal sperm reserves were reduced in a dose-dependent manner. Indicators of lipid peroxidation were increased while activities of superoxide dismutase and catalase in all three epididymal regions decreased. Histological malformations were observed in the epididymis. Exposure to benzo(a)pyrene deranges the antioxidant defense system and induces histological changes in the epididymis. 相似文献
236.
Reddy Maddigapu P Minero C Maurino V Vione D Brigante M Mailhot G 《Chemosphere》2010,81(11):1401-1406
Anthraquinone-2-sulphonate (AQ2S) under UVA irradiation is able to oxidise nitrite to (·)NO(2) and to induce the nitration of phenol. The process involves the very fast reactions of the excited triplet state (3)AQ2S(*) and its 520-nm absorbing exciplex with water, at different time scales (ns and μs, respectively). Quinones are ubiquitous components of coloured dissolved organic matter (CDOM) in surface waters and AQ2S was adopted here as a proxy of CDOM. Using a recently developed model of surface-water photochemistry, we found that the oxidation of nitrite to (·)NO(2) by (3)CDOM(*) could be an important (·)NO(2) source in water bodies with high [NO(2)(-)] to [NO(3)(-)] ratio, for elevated values of column depth and NPOC. 相似文献
237.
Reddy MV Babu KS Balaram V Satyanarayanan M 《Environmental monitoring and assessment》2012,184(4):1991-2000
The surface water qualities of Hussainsagar, an eutrophic urban lake in the midst of twin cities of Hyderabad and Secunderabad
(India) receiving large quantities of external inputs—both untreated municipal sewage containing industrial effluents, and
treated sewage, a large number of annually immersed idols of God and Goddess, and intense boating activities were assessed
in relation to the concentration of elements including heavy metals of the water along the necklace road of the lake. Elemental
analyses of water using ICP-MS revealed 26 elements including heavy metals—As, Cd, Cr, Ni, Pb, Cu, Fe, Mn, Se, Ba, Zn, Mo,
V, Co, Ag, Sr, Rb, Mg, K, Ca, Al, Si, Sb, Na, Li, and B, in the surface water of the lake. Of these, the first 15 elements
were found in elevated concentrations in the water at the outfall point of the untreated municipal sewage (site 3), which
was the main dominating source of contamination of the lake water while Cu and Sb were recorded in higher concentrations at
the outfall of treated effluent from Sewage Treatment Plant, and three elements (Ba, Si, and B) were in higher concentration
at the sites of outfall of sewage flowing from an oxygenated pond (site 4), Ca, Zn, and Sr, at the site immersed with idols
(site 1), and Pb, Ag, and Al at the center of the lake (site 5) with intense boating activities. Concentrations of most of
these elements exceeded the maximum permissible limits of national (Indian Council Medical Research) standards for drinking
water. The concentrations of most of the elemental contaminants showed significant positive correlations between them. 相似文献
238.
P. Rama Chandra Prasad Nidhi Nagabhatla C. S. Reddy Stutee Gupta K. S. Rajan S. H. Raza C. B. S. Dutt 《Environmental monitoring and assessment》2010,160(1-4):541-553
The present study outlines an approach to classify forest density and to estimate canopy closure of the forest of the Andaman and Nicobar archipelago. The vector layers generated for the study area using satellite data was validated with the field knowledge of the surveyed ground control points. The methodology adopted in this present analysis is three-tiered. First, the density stratification into five zones using visual interpretation for the complete archipelago. In the second step, we identified two island groups from the Andaman to investigate and compare the forest strata density. The third and final step involved more of a localised phytosociological module that focused on the North Andaman Islands. The results based on the analysis of the high-resolution satellite data show that more than 75% of the mangroves are under high- to very high-density canopy class. The framework developed would serve as a significant measure to forest health and evaluate management concerns whilst addressing issues such as gap identification, conservation prioritisation and disaster management—principally to the post-tsunami assessment and analysis. 相似文献
239.
240.
Abstract A simple technique was demonstrated for determining the potential for synthetic organics to stress microbial populations. Oxidized Crowley and Cecil soil materials were amended with varying concentrations of 2,4‐D and methyl parathion, flooded, and then analyzed for changes in pH, redox potential, and levels of soluble plus exchangeable Fe, Mn, and Zn, all of which may be directly or indirectly influenced by the activity of soil microorganisms. At the concentrations tested (up to 75 ppm), there was little effect of 2,4‐D, but methyl parathion apparently did affect microbial activity contributing to changes in the measured soil properties upon flooding. This approach may be a useful technique for screening various compounds for their potential to stress microbial activity that, for many researchers, would be easier than direct observations of microbial parameters such as population numbers and classifications, and enzyme levels. 相似文献