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41.
RB Singh MA Niaz SS Rastogi S Bajaj Z Gaoli Z Shoumin 《Canadian Metallurgical Quarterly》1998,17(6):564-570
OBJECTIVE: To determine the association between current zinc intake and prevalence of coronary artery disease (CAD) and diabetes as well as factors associated with insulin resistance. DESIGN, SUBJECTS AND METHODS: In this cross sectional survey, 3575 subjects, aged 25 to 64 years, including 1769 rural (894 men. 875 women) and 1806 urban (904 men, 902 women) subjects were studied. The survey methods included questionnaires for 7-day food intake record, physical examination, and electrocardiography using World Health Organization criteria. RESULTS: The prevalence of CAD, diabetes and glucose intolerance was significantly higher among subjects consuming lower intakes of dietary zinc. There was a higher prevalence of hypertension, hypertriglyceridemia and low high-density lipoprotein cholesterol levels which showed significant upward trend with lower zinc intakes. Serum lipoprotein (a) and 2-hour plasma insulin levels also were associated with low zinc intake. Multivariate logistic regression analysis after adjustment for age showed that zinc intake and CAD were inversely associated. Serum zinc (odds ratio:men 0.77, women 0.57), serum triglycerides (men 0.86, women 0.81), blood pressure (0.83 men, women 0.76), diabetes mellitus (men 0.90, women 0.85), central obesity (men 0.88, women 0.87), glucose intolerance (men 0.66, women 0.57) and low high-density lipoprotein cholesterol (men 0.72, women 0.70) were significant risk factors for CAD (explained by tertiles of zinc status) in urban subjects. These associations were not observed in rural subjects. CONCLUSION: Lower consumption of dietary zinc and low serum zinc levels were associated with an increased prevalence of CAD and diabetes and several of their associated risk factors including hypertension, hypertriglyceridemia and other factors suggestive of mild insulin resistance in urban subjects. 相似文献
42.
RB Singh GS Wander A Rastogi PK Shukla A Mittal JP Sharma SK Mehrotra R Kapoor RK Chopra 《Canadian Metallurgical Quarterly》1998,12(4):347-353
Adherence with inhaled beta-agonists and corticosteroids in 24 asthmatic children was tracked over 3 months utilizing the metered-dose inhaler chronolog (MDIC). Patients seldom took all of their medications as prescribed, and failed to take any inhaled corticosteroid doses on a median of 41.8% of days or inhaled beta-agonists on 28.1% of days despite prescribed daily use. Medication nonadherence was correlated with lower levels of asthma knowledge (Asthma Knowledge Questionnaire) and family dysfunction (Family Assessment Device), but not child behavior disorder (Child Behavior Checklist). Patients tended to dramatically over-report medication use. Improved identification of the markers of nonadherence can directly facilitate more efficient targeting of behavioral interventions, resulting in improved adherence, better illness control, and less requirement of urgent medication intervention. 相似文献
43.
Molecular typing is now widely used in mycobacteriology as a significant addition to conventional epidemiological studies. Several methods are available that differ with respect to their discriminating power and to the genetic marker used. Restriction fragment length polymorphism (RFLP) done using the IS6110 insertion sequence has been widely used for typing Mycobacterium tuberculosis. More recently, short repetitive DNA sequences have been used as RFLP markers, as well as for other typing methods involving gene amplification. One of these methods, the inter-direct repeat (DR)-based spoligotyping method, is rapid, directly applicable to clinical specimens, and highly discriminating. 相似文献
44.
The application of electrogenerated iodonium ion, acting as catalytic electron carrier, has been taken into account in the intramolecular oxidative cyclization reaction of 2-nitroaniline on graphite anode in the preparation of benzofuroxan, which is of great synthetic utility. 相似文献
45.
The primary heat transport system of 500 MWe Indian PHWR comprises of straight pipes, elbows and headers. A study was conducted to qualify piping system for leak before break. R-6 method was used to assess integrity of system for leakage size crack (LSC), the margins on crack initiation load and unstable crack growth loads. Option 2 (material specific failure assessment diagram), Category 3 (ductile tearing) analysis was used for straight pipes, elbows and header. In order to enhance the confidence in the analytical results, detailed sensitivity analysis was also performed. For sensitivity analysis, variation in material properties, LSC was considered. The effect of variation in temperature on material properties was also considered. Tensile and fracture properties used for base and weld material data were generated from pipe material obtained from 220 MWe Nuclear Power Plant, under construction. 相似文献
46.
In response to the appliance industry's growing need for high-quality lamination steels for energy-efficient motors, intensive research efforts are being made to develop low-loss high-permeability products with appropriate selection of composition and processing. This has led to the development of new decarburized semiprocessed lamination steels with lower losses (~33% improved) and AC peak relative permeability close to 2000 at 1.5 T and 60 Hz. The magnetic properties of some of these steels are equivalent to or better than those of high-silicon steels. These efforts are described with emphasis on (a) requirements for achieving improved magnetic properties, (b) benefits of new steels over standard products, (c) annealing response of new products, and (d) current research activities aimed at providing future products with excellent magnetic characteristics 相似文献
47.
A two dissimiliar unit standby system is analysed. The priority unit can either be in normal or partial operative mode. When the unit fails from the partial mode, it undergoes minor repair and the unit becomes operative with different failure rate. If this unit fails again, it goes to major repair after which it works as good as new. The standby unit while in use is either operative or failed. This non priority unit fails without passing through the partial failure mode and undergoes only one type of repair with different repair time distribution. Failure and repair time distributions are negative exponential and general respectively. Regenerative technique in MRP is applied to obtain several reliability characteristics of interest to system designers. 相似文献
48.
A novel generalized approach to phase-shifting interferometry in which phase distribution in an interferogram is evaluated in the presence of nonsinusoidal waveforms and piezoactuator device miscalibration is proposed. The approach is based on the underlying rotational invariance of signal subspaces spanned by two temporally displaced data sets. The advantage of the proposed method lies in its ability to identify arbitrary phase-step values pixelwise from an interference signal buried in noise. The robustness of the proposed method is investigated by addition of white Gaussian noise during the simulations. 相似文献
49.
50.
Adaptive neural net (ANN) model of hot metal desulphurization is first optimized by various search methods including the golden section search and Davies-Swann-Campey methods. Logarithmic preprocessing of input data leads to a further improvement in generalization ability of the net. Genetic adaptive search (GAS) method is used to optimize the mathematical model for desulphurization and when the input data are preprocessed with this optimized model and fed into an artificial neural net, the generalization ability of the net becomes even better. Best results are obtained when using GAS to optimize the interconnection weights during the training phase, while training data are preprocessed through a mathematical model already optimized by GAS. For every process several options presented by a combination of ANN and GAS must be systematically investigated before choosing the ultimate model for predictions on shop floor. 相似文献