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1.
BACKGROUND: The prognosis of acute inferior myocardial infarction is worse when it is complicated by right ventricular infarction. ST elevation in the right precordial leads is one of the reliable methods for detecting acute right ventricular infarction. The purpose of the study was to examine the relation between ST elevation in the right precordial electrocardiographic leads during acute inferior infarction and the severity of right ventricular systolic dysfunction. METHODS: This study analyzed the relation between ST elevation > or = 0.1 mV in V4R and the severity of right ventricular systolic dysfunction in 43 consecutive patients (men/women: 35/8; average age 62+/-9 years) with acute inferior myocardial infarction with a rapid-response Swan-Ganz catheter to measure the right ventricular ejection fraction (RVEF). RESULTS: RVEF was significantly lower in patients with ST elevation (n = 18) than in those without (n = 25) (33%+/-6% vs 40%+/-9%, p = 0.010). If the infarct-related lesion was located in the proximal right coronary artery, RVEF tended to be lower than if the lesion was located in the distal right coronary artery or the left circumflex coronary artery (33%+/-10% vs 37%+/-9% vs 42%+/-9%, p = 0.101). Logistic regression analysis demonstrated that ST elevation in V4R was the only independent predictor of depressed RVEF (odds ratio = 5.31, 95% confidence interval = 1.28 to 22.1, p = 0.022). CONCLUSION: ST elevation in lead V4R during acute inferior myocardial infarction predicts right ventricular systolic dysfunction.  相似文献   
2.
The direct measurement of scattering and total losses of very good uniform optical fibres has been proposed and verified for the first time by analysing the scattering light with the variation of input launching power of an He-Ne laser by an optical attenuator. The scattered light has been detected by the cubic detector at different positions along the fibre.  相似文献   
3.
A freezing point depression system (dimethyl sulfoxide-Tullanox-water-polyvinyl alcohol) has been developed which prevents icing at a cold surface at moderate temperatures below 0°C in ambient air of 12.8°C and 70% relative humidity for several days. No drainage of liquids occurs during this time; the increase in weight is moderate (20–30%). The system is non-toxic and not inflammable. The system is easily applied to surfaces and is economical.  相似文献   
4.
Instruments have been developed for the testing of stiffness of polymers in various gaseous environmental “atmospheres” over a large range of temperatures. They are based on the cantilever principle, where a small strip of a specimen is deflected statically or periodically. Changes in stiffness are measured as function of the bending force or power input, respectively. The dynamic instrument responds very sensitively to the onset of cracking in specimens due to ozone exposure. The static instrument is well suited for measuring the onset of rapidly increasing stiffness as temperatures are lowered.  相似文献   
5.
The magnetic anisotropy of V3O5 was investigated by magneto-torque measurements in the temperature range from 4.2 to 300 K. It has been confirmed that the Néel temperature is about 75 K and that two of the three principal axes vary with temperature in both the paramagnetic and antiferromagnetic states. The results are explained on a simplified four-sublattice model.  相似文献   
6.
Transient expression of genes coding for the poly-gamma-glutamate (gammaPGA) synthetase system (pgs) was investigated in tobacco plants. Three genes of the pgs, pgsA, pgsB and pgsC, were separately placed under the control of the CaMV 35S promoter and introduced into tobacco leaves via Agrobacterium infection. Synthesized gammaPGA in plant tissues was detected immunologically with mouse anti-gammaPGA antiserum which specifically reacts with gammaPGA on a nitrocellulose membrane. Confirmation of gammaPGA biosynthesis in the transient expression analysis in tobacco tissue indicates that subunits of pgs complex were expressed and reassembled in a functional form.  相似文献   
7.
In this work, a detailed TEM sample preparation recipe based on a wedge polishing technique for GaN-based materials is presented. The obtained samples have atomically flat surfaces without any obvious surface damages such as the formation of amorphous layers. A composition estimation of Al(x)Ga(1-x)N from Z-contrast STEM imaging is carried out using these samples. The results are in good accord with the nominal composition.  相似文献   
8.
The present study goes into the search for the safety domain of civil engineering structures. The objective is to show how a reliability-evaluation brought by a mechanical sizing can be obtained. For that purpose, it is necessary to have a mechanical model and a reliability model representing correctly the behavior of this type of structure.It is a question on one hand, to propose a formulation for the nonlinear calculation (mechanical nonlinearity) of the spatial structures in trusses, and on the other hand, to propose or to adapt a formulation and a modeling of the reliability. The principle of Hasofer-Lind can be applied, in first approach, for the reliability index estimation, scenarios and the probability of failure.The made check concerned metallic in truss structures. Finally, some structures are calculated using the method adapted by Hasofer-Lind to validate the probability approach of the reliability analysis.  相似文献   
9.
A CVD process with a high density of CNTs has been developed on doped silicon material thanks to plasma pre-treatment of the catalyst. With this process small diameter double and triple wall CNTs with an average diameter of 3.8 nm have been grown. The density of the best materials on blanket substrate is larger than 1012 cm? 2. These materials have been successfully integrated in via holes with a diameter ranging between 1 µm and 0.3 µm with an equivalent density. In 140 nm hole diameter large 70 nm bundle formations have been observed. In these bundles a density of CNT walls close to 1013 cm? 2 has been estimated.  相似文献   
10.
Colloidal nanoplatelets (NPLs) and nanosheets with controlled thickness have recently emerged as an exciting new class of quantum-sized nanomaterials with substantially distinct optical properties compared to 0D quantum dots. Zn-based NPLs are an attractive heavy-metal-free alternative to the so far most widespread cadmium chalcogenide colloidal 2D semiconductor nanostructures, but their synthesis remains challenging to achieve. The authors describe herein, to the best of their knowledge, the first synthesis of highly stable ZnO NPLs with the atomically precise thickness, which for the smallest NPLs is 3.2 nm (corresponding to 12 ZnO layers). Furthermore, by means of dynamic nuclear polarization-enhanced solid-state 15N NMR, the original role of the benzamidine ligands in stabilizing the surface of these nanomaterials is revealed, which can bind to both the polar and non-polar ZnO facets, acting either as X- or L-type ligands, respectively. This bimodal stabilization allows obtaining hexagonal NPLs for which the surface energy of the facets is modulated by the presence of the ligands. Thus, in-depth study of the interactions at the organic–inorganic interfaces provides a deeper understanding of the ligand–surface interface and should facilitate the future chemistry of stable-by-design nano-objects.  相似文献   
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