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151.
The present study evaluates the haemato-biochemical responses associated with fipronil exposure [(±)-5-amino-1-(2,6-dichloro-α,α,α-trifluoro-p-tolyl)-4-trifluoromethylsulfinyl-pyrazole-3-carbonitrile] in Cyprinus carpio fry. Fish were exposed to sublethal concentration (1/3rd of LC50) (0.142 mg L?1) for 15 days and corresponding changes in different haemato-biochemical parameters were recorded at the end of experimental period. Significant (P < 0.05) increase in white blood cell counts, blood glucose, serum complement reactive protein and serum cortisol level were noticed, whereas haemoglobin and serum total protein contents were significantly (P < 0.05) decreased. Aspartate amino transferase, catalase and super oxide dismutase activities were significantly (P < 0.05) increased while alkaline phosphatase and malate dehydrogenase activities were significantly (P < 0.05) decreased. Similarly, 47 % inhibition in acetylcholine esterase activity was noticed due to fipronil stress. Results indicated that sublethal exposure of fipronil can induce haemato-biochemical alterations causing stress to C. carpio fry. Thus, haemato-biochemical parameters can be used as biomarkers for the sublethal toxicity of fipronil in the water bodies.  相似文献   
152.
The genetic diversity of five feral populations of Asian Sea bass, Lates calcarifer collected from five isolated locations in India viz., Paradeep, Chilka lake, Kakinada, Chennai and Mumbai was studied using randomly amplified polymorphic DNA. Out of 20 primers screened, 5 decamer random primers amplified a total of 373 DNA bands of which 137 bands were polymorphic. The Kakinada population showed the highest polymorphism (65.71 %) whereas the Chennai population showed the lowest (48.28 %). The inter-population genetic similarity (GS) values estimated for the five populations were checked by one-way ANOVA and found to be significantly different at P < 0.01. The highest inter-population GS was found between Paradeep and Chilka (0.909) and lowest was between Kakinada and Chennai (0.800). Genetic distance tree developed by Unweighted Pair Group Method with Arithmetic Mean cluster analysis depicted that the Sea Bass of Paradeep, Chilka and Kakinada belong to one cluster while Chennai and Mumbai populations make different cluster. Overall, Randomly Amplified Polymorphic DNA technique could be used for genetic differentiation of diverse populations of Sea bass to provide information on their population genetic structure.  相似文献   
153.
Abstract

Hemoglobinopathies and thalassemias are the most commonly encountered monogenic disorders of blood in humans, posing a major genetic and public health problem round the globe. Hb S (HBB: c.20A>T)-β-thalassemia (β-thal) is a compound aberrant heterozygosity with inconsistent phenotypic expression, which are poorly described and clinically mapped. Comprehensive genetic characterization of such a population is highly warranted for complete understanding of the clinical heterogeneity, disease prognosis and therapeutic management. In this study, Hb S-β-thal (n?=?60) patients, strictly defined by varying degrees of clinical presentations, were selected to evaluate their genotype-phenotype agreement. Furthermore, β-globin (n?=?120) and α-globin gene clusters (n?=?60) were genetically characterized and statistically correlated with clinical terminologies to explain the clinical heterogeneity. Our results revealed the association of the Arab-Indian haplotypes with nine different frameworks of β-thal together with the modulating role of α-thalassemia (α-thal). The study subjects, including carriers of β-thal haplotype III [– – – – – – –] (8.0%), presented with varying severe patterns of clinical symptoms such as painful crisis, multiple infections and splenomegaly, as an outcome of significantly less Hb F and higher Hb S levels (p?<?0.5). The study findings indicated that together with α-thal, β-thal haplotypes and Hb F levels, may possibly provide a close justification to support the clinical heterogeneity in the study population.  相似文献   
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Results of a prospective study of the association between environmental factors and malaria occurrence among 1461 individuals in an Indian rural community are reported. A multiplicative model was fitted by relating malaria positivity with different environmental risk factors as categorical variables. The risk of acquiring malaria infections varied significantly within a village stratified by proximity of breeding sources to human dwellings (chi 2 = 19.87, df = 5, p = 0.0000) and different types of houses (chi 2 = 11.32, df = 2, p = 0.0035). People residing in thatched houses with [Relative Risk (RR) = 6.72] and without false ceiling (RR = 11.27) are exposed to greater risk of contracting malaria infections when compared to tiled houses (RR = 1.00). However, malaria infection was not significantly associated with proximity of cattlesheds to human dwellings (chi 2 = 1.54, df = 2, p = 0.46). A significantly high risk was observed in zones where the cattle to man ratio was very low and vice versa (chi 2 = 15.32, df = 6, p = 0.018). These data suggest and corroborate with earlier studies that transmission is a local problem and it varies within a village according to the microepidemiological factors.  相似文献   
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N Sahu  B K Patnaik 《Gerontology》1988,34(4):179-183
Intraperitoneal injection of thyroxine (T4; 1 microgram/g body weight on alternate days, seven doses) to male garden lizards of three different age groups caused a stimulation of hepatic succinic dehydrogenase activity, the degree of response being higher in the old (63%) than in middle-aged (39%) and young (31%). Percent inhibition of enzyme activity following thiourea treatment (0.05 mg/g body weight on alternate days, three doses) was higher in middle-aged lizards (24%) than in young (10%) and old (12%) ones.  相似文献   
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