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161.
AIM: To assess the clinical impact of hyperinsulinism and major coronary risk factors in patients with angiographically documented or excluded coronary artery disease (CAD), a clinical study was carried out in 268 men admitted for left heart catheterization. METHODS: Fasting immunoreactive insulin (IRI) levels were correlated to all major cardiovascular risk factors and to the presence and degree of CAD. RESULTS: IRI levels were correlated significantly with the degree of CAD (one-vessel disease: mean IRI 9.45 microU/ml +/- 0.43 SEM; two-vessel disease: mean IRI 10.4 microU/ml +/- 0.71 SEM; three-vessel disease: mean IRI 11.88 microU/ml +/- 0.98 SEM) and inversely to the high-density lipoprotein level (P < 0.05). In patients with arterial hypertension, IRI levels were elevated, without a significant difference between those with and those without CAD, whereas the IRI levels of non-hypertensive men with CAD (n = 81; mean IRI 9.85 microU/ml +/- 0.51 SEM) differed significantly (P < 0.05) from those of non-hypertensive men without CAD (n = 59; mean IRI 7.76 microU/ml +/- 0.43 SEM). IRI levels were significantly higher (P < 0.05) in obese patients (n = 65; mean IRI 11.68 microU/ml +/- 0.70 SEM versus n = 203; mean IRI 9.32 microU/ml +/- 0.34 SEM), in patients with elevated triglycerides (n = 58 mean IRI 11.59 microU/ml +/- 0.81 SEM versus n = 210; mean IRI 9.42 microU/ml +/- 0.33 SEM), and in patients with lowered HDL cholesterol (n = 178; mean IRI 11.06 microU/ml +/- 0.63 SEM versus n = 90; mean IRI 9.29 microU/ml +/- 0.34 SEM). Diabetic patients on angiotensin converting enzyme inhibitor therapy (n = 11; mean IRI 7.91 microU/ml +/- 0.91 SEM) had significantly (P < 0.05) lower IRI levels than those not treated with ACE inhibitors (n = 25; mean IRI 12.96 microU/ml +/- 1.47 SEM). IRI levels exceeding 8 microU/ml were associated with a 1.98-fold risk for CAD compared with IRI levels below 8 microU/ml. Stepwise logistic regression showed that insulin was an independent determinant of CAD. CONCLUSION: Knowledge of the fasting insulin level is an important contribution to the identification of patients with, or at risk of, CAD.  相似文献   
162.
The diffusion and use of Advanced Manufacturing Techniques (AMT) in Dutch factories that is expected to occur at the beginning of the next century, has been analyzed in a Delphi study with 23 Dutch experts. Four possible scenarios for ‘factories of the future’ were identified; in these special attention was paid to the role that AMT might play. It appeared that AMT would play a different role, depending on the external environment and internal condition, varying from very limited to rather extended. Introducing AMT in these ways should have a positive impact on competitive position of the enterprises, company employment, and the industrial structure.  相似文献   
163.
This paper presents a review of the main telecommunications systems now under development in France. First, it gives the general objectives, the basic options, and the general design of the new electronic switching system E. 1 defined by CNET, with the principal characteristics of the E.10 and E.12 variants, and general planning of studies and development in process in this field. Then a summary of the new transmission systems under development such as digital systems on cables, radio relays, or circular waveguide, as well as analog systems, including submarine and space systems is given. Finally, some considerations are given to the increasing use of information processing for the telecommunication network, and to the development of specialized networks for new kinds of information.  相似文献   
164.
Beryllium experiences (n, 2n) multiplication reaction for neutrons having energy above the threshold of ≈ 1.8 MeV. In the case of beryllium-reflected/moderated reactor assemblies these (n, 2n) neutrons contribute additional reactivity. This paper evaluates the reactivity contribution due to (n, 2n) reactions in the Be and BeO reflector of reflected 233U uranyl nitrate solution systems in spherical geometry in the light of the latest 9Be cross-section data. The results shows that the (n, 2n) reactions in a given thickness of reflector are directly proportional to the core leakage and thus very much a function of core radius. In the core radius range of 4–15 cm the reactivity bonus due to (n, 2n) reactions in a 30-cm thick Be reflector varies from 6.2 to 3.0%, which corresponds to a critical mass saving of ≈18–9%. The corresponding reactivity contributions for BeO reflected systems are ≈25% lower.  相似文献   
165.
Leather tanning processes cause environmental impact as a result of the generation of solid waste, wastewater, and release of gases. The improper disposal of such waste may promote the oxidation of chromium, for example, changing it from chromium (III) to chromium (VI), in which becomes extremely toxic. In this study, composites were prepared from natural rubber (NR) with industrial leather waste (Lw), varying the waste amount from 20 to 80 phr, with the aim of recycling leather waste. The microstructure, mechanical properties and rheological properties of composites were investigated. The results showed that Lw increased tensile strength and hardness, with good reproducibility, and uniformity of residuals distributed as fillers (miscible materials). These properties indicate that this composite material can be used as raw material for the manufacture of shoes, bags, upholstery, etc. POLYM. COMPOS., 36:2275–2281, 2015. © 2014 Society of Plastics Engineers  相似文献   
166.
The modifications of the surface and subsurface properties of p-type multicrystalline silicon (mc-Si) after wet chemical etching and hydrogen plasma treatment were investigated. A simple heterojunction (HJ) solar cell structure consisting of front grids/ITO/(n)a-Si:H/(p)mc-Si/Al was used for investigating the conversion efficiency. It is found that the optimized wet chemical etching and cleaning processes as a last technological step before the deposition of the a-Si:H emitter are more favorable to HJ solar cells fabrication than the hydrogenation. Solar cells on p-type mc-Si were prepared without high-efficiency features (point contacts, back surface field). They exhibited efficiencies up to 13% for a cell area of 1 cm2 and 12% for a cell area of 39 cm2.  相似文献   
167.
In supramolecular materials, molecular building blocks are designed to interact with one another via non‐covalent interactions in order to create function. This offers the opportunity to create structures similar to those found in living systems that combine order and dynamics through the reversibility of intermolecular bonds. For regenerative medicine there is a great need to develop materials that signal cells effectively, deliver or bind bioactive agents in vivo at controlled rates, have highly tunable mechanical properties, but at the same time, can biodegrade safely and rapidly after fulfilling their function. These requirements make supramolecular materials a great platform to develop regenerative therapies. This review illustrates the emerging science of these materials and their use in a number of applications for regenerative medicine.  相似文献   
168.
The paper presents the design of an assistive reading tool that integrates read-aloud technology with eye tracking to regulate the speed of reading and support struggling readers in following the text while listening to it. The paper describes the design rationale of this approach, following the theory of auditory–visual integration, in terms of an automatic self-adaptable technique based on the reader's gaze that provides an individualized interaction experience. This tool has been assessed in a controlled experiment with 20 children (aged 8–10 years) with a diagnosis of dyslexia and a control group of 20 children with typical reading abilities. The results show that children with reading difficulties improved their comprehension scores by 24% measured on a standardized instrument for the assessment of reading comprehension and that children with more inaccurate reading (N = 9) tended to benefit more. The findings are discussed in terms of a better integration between audio and visual text information, paving the way to improve standard read-aloud technology with gaze-contingency and self-adaptable techniques to personalize the reading experience.  相似文献   
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