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991.
Farhana Zahir Shameem J Rizvi Soghra K Haq Rizwan H Khan 《Indian journal of clinical biochemistry : IJCB》2006,21(2):149-152
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose
mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the
effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male
albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were
tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation,
nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing
methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was
a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent
reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more
specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion
that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help
combat the risk of developing such disorders in ensuing years. 相似文献
992.
Amanda Spink Bernard J. Jansen Chris Blakely Sherry Koshman 《Information processing & management》2006
The performance and capabilities of Web search engines is an important and significant area of research. Millions of people world wide use Web search engines very day. This paper reports the results of a major study examining the overlap among results retrieved by multiple Web search engines for a large set of more than 10,000 queries. Previous smaller studies have discussed a lack of overlap in results returned by Web search engines for the same queries. The goal of the current study was to conduct a large-scale study to measure the overlap of search results on the first result page (both non-sponsored and sponsored) across the four most popular Web search engines, at specific points in time using a large number of queries. The Web search engines included in the study were MSN Search, Google, Yahoo! and Ask Jeeves. Our study then compares these results with the first page results retrieved for the same queries by the metasearch engine Dogpile.com. Two sets of randomly selected user-entered queries, one set was 10,316 queries and the other 12,570 queries, from Infospace’s Dogpile.com search engine (the first set was from Dogpile, the second was from across the Infospace Network of search properties were submitted to the four single Web search engines). Findings show that the percent of total results unique to only one of the four Web search engines was 84.9%, shared by two of the three Web search engines was 11.4%, shared by three of the Web search engines was 2.6%, and shared by all four Web search engines was 1.1%. This small degree of overlap shows the significant difference in the way major Web search engines retrieve and rank results in response to given queries. Results point to the value of metasearch engines in Web retrieval to overcome the biases of individual search engines. 相似文献
993.
J. B. Varuna Kumara N. R. Ravikumara Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2016,31(4):390-401
Folic acid is used for preventing and treating multiple diseases and disorders, administered in the form of oral supplements. The present research work was aimed to study the influence of two non-ionic surfactants Poloxamer and Tween 80 (Polysorbate 80) on pectin submicrospheres formulations. Typical natural polymer pectin was used to encapsulate folic acid by cross linking method. The resultant submicrospheres contributed to improve the aqueous solubility to enhance the bioavailability of folic acid. During investigation, it was observed that pectin polymers influenced kinetics of the rate of reaction more intensively than the surfactants. The physical phenomenon caused the change in their size, shape and chemistry of pectin polymers transforming into submicrospheres in aqueous condition. The characteristic differences of submicrospheres were assessed by scanning electron microscopy, differential scanning calorimetry and Fourier-transform infrared spectroscopy. The average diameters of the submicrospheres ranged between 250 and 500 nm. The encapsulation efficiency of submicrospheres ranged between 80 and 96 %. The characteristic swelling behavior of lyophilized submicrospheres was influenced by the ratio of pectin polymers and folic acid used in the formulations. The submicrospheres systems exhibited controlled release of folic acid due to the pH-dependent solubility of pectin polymers in aqueous medium. The submicrospheres showed good haemocompatibility suggesting them to be promising candidates for oral delivery. 相似文献
994.
B. G. C. Maisonneuve T. Honegger J. Cordeiro O. Lecarme T. Thiry D. Fuard K. Berton E. Picard M. Zelsmann D. Peyrade 《Biomicrofluidics》2016,10(2)
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks. 相似文献
995.
Bharti Jain J. Kumarasamy Chandrakala Gholve Savita Kulkarni M. G. R. Rajan 《Indian journal of clinical biochemistry : IJCB》2017,32(2):193-199
Serum thyroglobulin (Tg) and thyroid stimulating hormone (TSH) measurements have evolved as important analytes for monitoring the prognosis of patients with differentiated thyroid cancer, post-thyroidectomy. Individual analyte immunoassay is the current practice in clinical pathology, but the simultaneous assay for all relevant analytes for a given disease, can reduce assay costs, improve patient compliance and give the clinician more information for an unequivocal diagnosis. Microarray immunoassay (MI) can achieve this goal and, hence, we have developed and validated a immuno-radiometric MI for quantitation of serum TSH and Tg by using highly micro-porous polycarbonate (PC) track-etched membranes (TEM) to immobilize the monoclonal anti-TSH and polyclonal anti-Tg antibodies in ~1 mm diameter spots. Non-competitive immunoassays were performed using mixture of 125I labeled monoclonal anti-TSH and anti-Tg antibodies. Phosphorimager was used to quantify the bound radioactivity. TSH and Tg were detected with detection limit of 0.07 µIU/ml and 0.13 ng/ml respectively, which is lower than the clinically required cut-off level. The assay showed: acceptable intra-assay precision within 20 % and recovery in the range of 76–111.2 %. MI compared well with the established immunoradiometric assay (IRMA) with r = 0.98, p < 0.01 (n = 41). No cross-reactivity was seen between the immobilized antibodies. Although two hormones are addressed in this report, MI using PC TEM and isotopic/non-isotopic tracers has the potential for highly automated multiplexed analysis. 相似文献
996.
Rachel K. Katch Samantha E. Scarneo William M. Adams Lawrence E. Armstrong Luke N. Belval Julie M. Stamm Douglas J. Cas 朱为模审校 《体育科研》2018,(2):31-46
参加有组织的体育运动和休闲活动存在发生严重伤病甚至死亡的内在风险。虽然造成体育运动或体育活动中猝死的原因有很多,但运动医学和循证标准治疗方面的进展已使临床医生得以更有效地预防、发现和治疗可能致死的伤患。随着研究与技术不断发展进步,当前的治疗标准正在不断发展以更好地改善患者的治疗效果。本文提出了10个与运动和体育活动中猝死的主要原因及其治疗手段有关的关键问题,未来开展的研究将提高运动员和休闲运动爱好者参与运动的安全度。当前证据表明,如采取正确的预防策略或最佳治疗方案,绝大多数的死亡案例是可以避免的。 相似文献
997.
998.
The measurement community needs to better understand how to interact with the media to effectively disseminate important findings from educational testing efforts. To this end, the current paper will review media coverage of educational testing and related issues and elaborate on areas of concern and opportunities for improved communication between measurement professionals and the media. Common misinterpretations of test results and measurement concepts will be discussed and suggestions for the clearer presentation and explanation of such information will be offered. Also, practical advice and strategies for handling different types of interactions with the media will be provided. The implications of focusing on this topic in the measurement profession and the inherent public value of this focus are highlighted throughout the paper. 相似文献
999.
The goals of this study were twofold: first, to examine whether preschool children's name-writing proficiency differentiated them on other emergent reading and writing tasks, and second, to examine the effect of name length on preschool children's emergent literacy skills including alphabet knowledge and spelling. In study 1, a range of emergent literacy tasks was administered to 296 preschool children aged 4-5 years. The more advanced name writers outperformed the less advanced name writers on all emergent literacy measures. Furthermore, children with longer names did not show superior performance compared to children with shorter names. In study 2, four measures of alphabet knowledge and spelling were administered to 104 preschool children. Once again, the more advanced name writers outperformed the less advanced name writers on the alphabet knowledge and spelling measures. Results indicated that having longer names did not translate into an advantage on the alphabet knowledge and spelling tasks. Name writing proficiency, not length of name appears to be associated with preschool children's developing emergent literacy skills. Name writing reflects knowledge of some letters rather than a broader knowledge of letters that may be needed to support early spelling. 相似文献
1000.
Nataly Loizidou‐Ieridou Jackie Masterson J. Richard Hanley 《Journal of Research in Reading》2010,33(3):247-262
The aim of the present study was to examine the spelling development of Greek‐speaking children in the early school grades. Although Greek orthography is regular for reading, it is much less transparent as far as spelling is concerned. Spelling development was investigated using a word spelling task designed to explore the effects of word length, familiarity and spelling regularity. One hundred and fifty normally developing primary school children living in Cyprus took part in the study. Results suggest that the children employed both phonological and lexical strategies in spelling Greek words. Results indicated that sub‐lexical procedures were more marked for younger children, whereas lexical processing was employed more widely by older children. The findings are interpreted in terms of stage developmental models. 相似文献