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101.
Sanchari Sinha Som Nath Singh Mantu Saha T. C. Kain A. K. Tyagi Uday Sankar Ray 《International journal of biometeorology》2010,54(1):85-92
High altitude (HA) is a multi-stressor environment comprising hypobaric hypoxia and cold. Climatic temperature varies with
seasonal variation at HA. The present study was undertaken to investigate the effect of ambient temperature on antioxidant
profile among sojourners at HA. The study was conducted on sojourners exposed to an altitude of 4,560 m in two different seasons
and categorized into two groups (SOJ 1, n = 63, ambient temp. at HA: −6o to +10oC; SOJ 2, n = 81, ambient temp. at HA: 3o–22oC). Blood was collected at sea level (SL) and after 4 weeks of HA exposure. Antioxidant
enzymes showed significant upregulation in SOJ 2 at HA. In SOJ 1, superoxide dismutase and glutathione peroxidase showed significant
upregulation but catalase and glutathione reductase showed significant decrease at HA. Non-enzymatic antioxidants showed significant
reduction in SOJ 1 whereas a sustained antioxidant profile was observed in SOJ 2 at HA. Oxidative stress markers showed higher
levels in SOJ 1 than SOJ 2 at HA. Differences observed between SOJ 1 and SOJ 2 at HA may be the consequence of different environmental
temperatures. Cold stress was higher in SOJ 1 as evidenced from the significantly lower oral temperature in SOJ 1 as compared
to SOJ 2. Cold- and hypoxia-induced increase in energy expenditure was significantly high in SOJ 1 than SOJ 2. To conclude,
chronic exposure to hypoxia in moderate climatic temperature has a potential preconditioning effect on antioxidant system,
but exposure to both cold and hypoxia causes greater oxidative stress due to altered metabolic rate. 相似文献
102.
Bharati S Mukherji D Pal M Som S Kumar Adak D Vasulu TS Bharati P 《Collegium antropologicum》2010,34(4):1207-1213
This paper analyzes the variation in the mean stature of adult males of a variety of population groups in India and examines the influence of geographical, climatic and ethnic factors on it. A considerable variation in mean stature has been found with respect to these three attributes. Variation "between" ethnic groups compared with "within" ethnic groups was found to be much more than that of geographical and climatic zones. Scheduled Castes (SC) and Scheduled Tribes (ST) populations have much low average height than that of General Castes (GC). Climatically dry and semiarid zones have a tendency to have higher stature than in the Monsoon areas. The mean height has been found to be the highest in north India. It is closely followed by west India. An interesting feature is that as one goes towards east and south the mean height gradually decreases. It is the lowest in islands. The mean heights have been regressed on geographical, climatic and ethnic factors, after converting these factors into binary variables. The regression analysis has strengthened the findings, that there is a highly significant relationship between height and geographical, climatic and ethnic factors. 相似文献
103.
Som A Harder C Greber B Siatkowski M Paudel Y Warsow G Cap C Schöler H Fuellen G 《PloS one》2010,5(12):e15165
Background
Analysis of the mechanisms underlying pluripotency and reprogramming would benefit substantially from easy access to an electronic network of genes, proteins and mechanisms. Moreover, interpreting gene expression data needs to move beyond just the identification of the up-/downregulation of key genes and of overrepresented processes and pathways, towards clarifying the essential effects of the experiment in molecular terms.Methodology/Principal Findings
We have assembled a network of 574 molecular interactions, stimulations and inhibitions, based on a collection of research data from 177 publications until June 2010, involving 274 mouse genes/proteins, all in a standard electronic format, enabling analyses by readily available software such as Cytoscape and its plugins. The network includes the core circuit of Oct4 (Pou5f1), Sox2 and Nanog, its periphery (such as Stat3, Klf4, Esrrb, and c-Myc), connections to upstream signaling pathways (such as Activin, WNT, FGF, BMP, Insulin, Notch and LIF), and epigenetic regulators as well as some other relevant genes/proteins, such as proteins involved in nuclear import/export. We describe the general properties of the network, as well as a Gene Ontology analysis of the genes included. We use several expression data sets to condense the network to a set of network links that are affected in the course of an experiment, yielding hypotheses about the underlying mechanisms.Conclusions/Significance
We have initiated an electronic data repository that will be useful to understand pluripotency and to facilitate the interpretation of high-throughput data. To keep up with the growth of knowledge on the fundamental processes of pluripotency and reprogramming, we suggest to combine Wiki and social networking software towards a community curation system that is easy to use and flexible, and tailored to provide a benefit for the scientist, and to improve communication and exchange of research results. A PluriNetWork tutorial is available at http://www.ibima.med.uni-rostock.de/IBIMA/PluriNetWork/. 相似文献104.
Malnutrition among children is prevalent in almost all the states in India. This study assesses the extent and causes of malnutrition in two eastern Indian states with similar climates, namely West Bengal and Assam, using data from the National Family Health Survey 1998-99 (NFHS-2). The three indices of malnutrition taken for analysis are weight-for-height (WHZ), height-for-age (HAZ) and weight-for-age (WAZ). These are assumed to depend on birth order, preceding birth interval, parent's educational status, working status of the mother, mother's age at delivery of the children, source of drinking water, toilet facilities and standard of living of the household. Logistic regression was carried out separately for each of the three indices on the explanatory variables for both the states. It was found that not all variables are equally important in determining whether a baby is underweight, or suffering from acute or chronic malnutrition. Also, the importance of variables is not the same in the two states. It was observed that the coefficients associated with the variables in determining weight-for-height are not significant compared with those for weight-for-age and height-for-age. 相似文献
105.
Barbosa JA Kellner AW Viana MS 《Proceedings. Biological sciences / The Royal Society》2008,275(1641):1385-1391
The discovery of a new dyrosaurid crocodylomorph from the well-dated Palaeocene deposits of northeastern Brazil sheds new light on the evolutionary history of this extinct group of marine crocodylomorphs that have survived the Cretaceous-Palaeogene (K-P) extinction crisis. Guarinisuchus munizi, the most complete member of this group collected in South America so far, is closely related to the African forms, and this fact suggests that dyrosaurids had crossed the Atlantic Ocean before the K-P boundary and dispersed from there to North America and other parts of South America. This discovery also suggests that on the coast of northeastern Brazil, dyrosaurids replaced the pre-existing Late Cretaceous fauna of diversified mosasaurs, a group of marine lizards, after the K-P extinction event, becoming the main predators, together with sharks, in shallow marine Palaeocene environments. More detailed stratigraphic records and detailed dating of the deposits with dyrosaurids are necessary to correlate this particular pattern found in the ancient northeastern Brazilian coast within the evolution of the group, especially in Africa. 相似文献
106.
107.
Origin of replication of Escherichia coli plasmid RSF 1030 总被引:14,自引:0,他引:14
108.
109.
Background
The International Consortium (FTDC) that revised the diagnostic criteria for behavioural variant frontotemporal dementia (bvFTD) did not have an Asian representation. Whether the revised criteria are equally useful in the early detection of Asian bvFTD patients therefore remains largely unexplored. Earlier studies have indicated differences in clinical manifestations in Indian and other Asian bvFTD patients when compared to western groups. There is an urgent need for clarification, given the projected exponential rise in dementia in these countries and the imminent clinical trials on bvFTD.Objective
To assess how Indian bvFTD patients fulfil the FTDC criteria, hypothesizing that our patients might present differently early in the illness.Method
In a hospital-based retrospective observational study, we assessed 48 probable bvFTD patients, diagnosed according to the FTDC criteria, for the speed with which these criteria were fulfilled, the frequency of individual symptoms and their order of appearance during the illness.Results
Most of our patients presented with moderate to severe dementia, in spite of having relatively short onset to diagnosis times. Patients on average took 1.4 years from onset to meet the FTDC criteria, with 90% of them presenting with four or more symptoms at diagnosis. Disinhibition was the commonest symptom and the first symptom in most patients.Conclusion
With most patients presenting with advanced and florid disease, the FTDC criteria have little additional impact in early identification of bvFTD in India. Modifying the criteria further could allow detection of Indian patients early enough for their inclusion in future clinical trials. 相似文献110.
Surface-enhanced Raman scattering (SERS) nanoparticles have been engineered to generate unique fingerprint spectra and are potentially useful as bright contrast agents for molecular diagnostics. One promising strategy for biomedical diagnostics and imaging is to functionalize various particle types (“flavors”), each emitting a unique spectral signature, to target a large multiplexed panel of molecular biomarkers. While SERS particles emit narrow spectral features that allow them to be easily separable under ideal conditions, the presence of competing noise sources and background signals such as detector noise, laser background, and autofluorescence confounds the reliability of demultiplexing algorithms. Results obtained during time-constrained in vivo imaging experiments may not be reproducible or accurate. Therefore, our goal is to provide experimentalists with a metric that may be monitored to enforce a desired bound on accuracy within a user-defined confidence level. We have defined a spectral reliability index (SRI), based on the output of a direct classical least-squares (DCLS) demultiplexing routine, which provides a measure of the reliability of the computed nanoparticle concentrations and ratios. We present simulations and experiments to demonstrate the feasibility of this strategy, which can potentially be utilized for a range of instruments and biomedical applications involving multiplexed SERS nanoparticles. 相似文献