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Iron deficiency evolves, slowly through several stages. Early iron deficiency caused a depletion in iron stores as shown by a reduction in the levels of hepatic non heme iron (44%) in the 7 days old pups born to iron deficient mothers. The hemoglobin levels and PCV (packed cell volume) were significantly reduced only after the age of three weeks. The activities of GABA (γ-amino butyric acid) shunt enzymes viz. GDH, GAD and GABA-T (glutamate dehydrogenase, glutamate decarboxylase and GABA-transaminase, respectively) and GABA content were found to decrease during gestation and/or lactation iron deficiency at 1 week (wk), 2wk, 3wk and 4wk of age in the developing rat brains. However GABA binding showed a significant increase at different age groups. The iron deficiency during lactational exposure showed significant alteration in most of the parameters only at the age of 3 weeks onwards. On rehabilitation with iron supplemented diet for 2 weeks, these altered parameters could not attain corresponding control values. A prolonged iron deficiency causing alterations in GABA may lead to neurological and behavioral alterations.  相似文献   
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Exposure to arsenic has been associated with several health hazards. Worldwide the main reason for chronic human intoxication with arsenic is intake of contaminated drinking water. Air acetylene type of atomic absorption spectrophotometer in combination with hydride generator accessory was used to analyze arsenic level in 25 water samples collected from 25 booster pumping stations and 313 water samples collected from tap water supply of 62 areas of Delhi. Results were analyzed using SPSS and Barlett’s Chi Square Test. Mean arsenic level detected in water samples collected from booster pumping stations was 0.00976 ppm (Range 0.000–0.017 ppm, Standard Deviation 0.006 and Standard error of Mean 0.00118). Maximum arsenic level (0.017 ppm) was found in water samples of booster pumping stations of Mehrauli, Punjabi Bagh and Ramjas Road. Mean arsenic level detected in samples collected from tap water supply was 0.013 ppm (Range 0–0.0430 ppm, Standard Deviation 0.00911 and Standard error of Mean 0.000515). In water samples of 42 areas arsenic level detected was exceeding WHO/EPA permissible limit of 0.01 ppm (10 ppb). The mean arsenic level detected in water samples of booster pumping station was within WHO/EPA permissible limit while mean arsenic level detected in tap water samples was marginally higher. Mixing of ground water and contamination through broken or leaking channel could be the possible reason of higher arsenic level in tap water. Continuous monitoring of quality of drinking water is required particularly in view of water contamination caused by industrial waste and uncontrolled ground water extraction.  相似文献   
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Many motile bacteria are propelled by the rotation of flagellar filaments. This rotation is driven by a membrane protein known as the stator-complex, which drives the rotor of the bacterial flagellar motor. Torque generation is powered in most cases by proton transit through membrane protein complexes known as stators, with the next most common ionic power source being sodium. Sodium-powered stators can be studied through the use of synthetic chimeric stators that combine parts of sodium- and proton-powered stator proteins. The most well studied example is the use of the sodium-powered PomA-PotB chimeric stator unit in the naturally proton-powered Escherichia coli. Here we designed a fluidics system at low cost for rapid prototyping to separate motile and non-motile populations of bacteria while varying the ionic composition of the media and thus the sodium-motive force available to drive this chimeric flagellar motor. We measured separation efficiencies at varying ionic concentrations and confirmed using fluorescence that our device delivered eightfold enrichment of the motile proportion of a mixed population. Furthermore, our results showed that we could select bacteria from reservoirs where sodium was not initially present. Overall, this technique can be used to implement the selection of highly motile fractions from mixed liquid cultures, with applications in directed evolution to investigate the adaptation of motility in bacterial ecosystems.  相似文献   
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Surveillance of drinking water is essentially a health measure intended to protect the public from water borne diseases. Hydride generator accessory coupled with atomic absorption spectrophotometer was used to analyze arsenic level in 49 ground water samples collected from different areas of Delhi. Arsenic level in ground water samples was in the range of 0.0170 to 0.100 ppm (Mean-0.0431, Standard Deviation-0.0136, Std. error of Mean-0.00194) with minimum concentration at Raney Well No. 7 (0.0170 ppm) and maximum at Kotla Mubarak Pur (0.100 ppm). Arsenic containing sediments and percolation of chemicals into soil as the result of dumping of garbage rich in chemicals into open landfills could be the possible source of arsenic in ground water of Delhi. Extensive survey and continuous monitoring is required to be made to assess the magnitude of problem and earlier intervention.  相似文献   
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Iron deficiency evolves slowly through several stages. Early iron deficiency caused a depletion in iron stores as shown by a reduction in the levels of hepatic non-heme iron in the new born of iron deficient mothers. Of particular importance is the effect on central nervous system, which leads to the defects in the cognition and learning processes in humans. Evidence is strong that in many under developed countries iron deficiency is the main cause of anaemia and supplementation under trial conditions may prevent some defects of iron deficiency but not all.  相似文献   
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Hyperferritinemia (>10,000 ng/ml) is an important hallmark used as an indicator of infection triggered macrophage activation syndrome leading to hemophagocytic lympho histiocytosis (HLH). Measurement of serum ferritin can be used in diagnosis as well as disease monitoring indicator and prognosis related to HLH, cAPS, sepsis, neoplasm and inflammatory conditions. It is a major contributor to manage critically ill patients as predicting and monitoring indicator. It can be used as acute phase response in conditions of MAS, AOSD, cAPS etc. A case study in our hospital showed extremely high ferritin values along with low hemoglobin, elevated LDH and triglycerides with positive MRSA in sputum culture and macrophage proliferation and hemophagocytosis in the bone marrow examination. Patient showed definite inverse relation with steroid therapy and serum ferritin levels.  相似文献   
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This study explores the changes in Computer Science (CS) students’ self-efficacy between entering study and the end of first year of university. It aims to give course leaders insights into the everyday challenges that affect students’ academic achievement and persistence into second year. The paper begins by proposing that the way CS is taught, the gender imbalance on CS courses, and the experience of the key transitional year into university might influence CS students’ non-continuation. It adopts an academic buoyancy conceptualisation of resilience. Acknowledging the scarcity of instruments covering CS students’ transition to university, the development of a new 20-item questionnaire is described, based on CS students’ own contributions of the challenges they faced during first year. The instrument is administered twice in one session to the same cohort. Analysis of paired responses indicates a loss of confidence to overcome challenges in most aspects, particularly staying motivated to study.  相似文献   
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