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41.
FA Amosenko VV Surkov TI Tikhonenko TS Maksimova 《Canadian Metallurgical Quarterly》1976,26(3):361-366
Progressive systemic sclerosis may be associated with focal myocardial fibrosis. Electrocardiographic abnormalities including conduction block are common in progressive systemic sclerosis but whether they are due to direct destruction of the specialized conduction tissue of the heart is uncertain. The conduction systems of 35 patients with progressive systemic sclerosis were studied. Of these 35 patients, 17 (50 per cent) had myocardial fibrosis of the type seen in progressive systemic sclerosis. In 10 of the 17, it was severe. Sinus node fibrosis was present in 13 patients and was nearly as frequent in those with as in those without the progressive systemic sclerosis myocardial lesion. Overlying pericarditis may have contributed to the fibrotic changes within the sinoatrial nodes in seven of the 13 patients. The atrioventricular node and main His bundles were normal. However, fibrotic changes were found in the proximal bundle systems in six patients. In three of the six, severe myocardial progressive systemic sclerosis was present, two had focal fibrous atrophy of the left bundle, and one had complete interruption of the right bundle. In only the latter patient was this reflected in the electrocardiogram which showed a right bundle branch block. Three patients without progressive systemic sclerosis myocardial lesions also had fibrous atrophy of a portion of the proximal left bundle branch, and in one the electrocardiogram showed an isolated left anterior hemiblock. Thus, morphologic abnormalities within the conduction system in our patients are difficult to attribute to progressive systemic sclerosis per se. Furthermore, although conduction abnormalities were more frequent in patients with myocardial disease, specific conduction system disease was not the cause in most patients. As has been noted in ischemic heart disease, the conduction system appears to be relatively spared from the myocardial changes of progressive systemic sclerosis, and the high incidence of conduction disturbances in this condition may be a consequence, rather, of damage to working myocardium. 相似文献
42.
43.
Allen-Gil SM Ford J Lasorsa BK Monetti M Vlasova T Landers DH 《The Science of the total environment》2003,301(1-3):119-138
The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula. We analyzed heavy metal concentrations in lichen (Cetraria cucullata), moss (Hylocomium splendens), soils, lake sediment, freshwater fish (Salvelinus alpinus, Lota lota and Coregonus spp.) and collared lemming (Dicrostonyx torquatus) from 13 sites between 30 and 300 km from Norilsk. Element concentrations were low in both C. cucullata and H. splendens, although concentrations of Al, Fe, Cu, Ni and Pb were significantly higher than those in Arctic Alaska, probably due to natural differences in the geochemical environments. Inorganic surface soils had significantly higher concentrations of Cd, Zn, Pb and Mg than inorganic soils at depth, although a lake sediment core from the eastern Taimyr Peninsula indicated no recent enrichment by atmospherically transported elements. Tissue concentrations of heavy metals in fish and lemming were not elevated relative to other Arctic sites. Our results show that the impact of the Norilsk smelting complex is primarily localized rather than regional, and does not extend northward beyond 100 km. 相似文献
44.
M. Ristich G. Brankovich T. Srechkovich M. Vlasova M. Kakazei M. L. Domingez-Patiño G. F. Domingez-Patiño I. I. Timofeeva L. P. Isaeva 《Inorganic Materials》2003,39(9):988-995
The phase formation in the CdO-rich part (10 wt % Bi2O3) of the CdO–Bi2O3 system was studied by x-ray diffraction, IR spectroscopy, electron microscopy, and other techniques. The results indicate that the grinding of the starting powder mixtures in a planetary mill leads to an inhomogeneous Bi2O3 distribution and a high defect density in the CdO and Bi2O3 particles. Sintering in the range 910–990 K gives rise to the formation of the h phase, whose content depends strongly on the mixture composition and sintering conditions. At sintering temperatures above its melting point, the h phase acts as a binder of CdO grains. 相似文献
45.
L. I. Kutsenko A. M. Bochek E. B. Karetnikova E. V. Vlasova B. Z. Volchek 《Theoretical Foundations of Chemical Engineering》2007,41(5):694-697
Synthetic conditions have been determined for obtaining sulfoethyl cellulose (SEC) from flax fiber manufacturing waste, namely, short fibers and lignified parts of pedicels (boon). The outcomes of sulfoethylation depend on the synthetic method, the molar ratio of the reactants, and the reaction time. Depending on the synthetic method, the resulting SEC is either insoluble or partially soluble in water. The products synthesized can be used as heavy-metal ion sorbents and as a substitute for carboxymethyl cellulose. 相似文献
46.
Conclusions Heat treatment of (Sn-Sb-0)-glass composites causes antimony and tin to diffuse into the glass. Around the particles, the glass acquires a diffusion profile. The diffusion coefficients of those ions at 1173 K are, respectively, 10–15 and 10–16 m2/sec.Translated from Poroshkovaya Metallurgiya, No. 11, pp. 28–32, November, 1990. 相似文献
47.
JM Bhatavdekar DD Patel N Ghosh PR Chikhlikar TI Trivedi TP Suthar SS Doctor NG Shah DB Balar 《Canadian Metallurgical Quarterly》1997,40(7):785-790
Lanepitant is a high-affinity, selective neurokinin-1 receptor (NK-1) and is effective in the dural inflammation model of acute migraine. Lanepitant 30, 80, and 240 mg given orally was evaluated in a double-blind, placebo-controlled crossover study to determine its effect in reducing migraine pain and severity of associated symptoms. Outpatients treated four migraine headaches of moderate or severe pain intensity with study drug according to a randomization schedule. They recorded their pain intensity and severity of migraine-associated symptoms at 30, 60, 90, and 120 min. Although 53 patients were randomly allocated to a treatment sequence, only 40 patients completed all treatments. There was no statistically significant difference in improvement in migraine pain at any time for any of the treatments. Additionally, there was no change in severity of migraine-associated symptoms associated with lanepitant therapy. No adverse events could be attributed to lanepitant. Lanepitant was ineffective orally in treating acute migraine in this trial. This may be due to poor bioavailability during a migraine attack. Alternatively, the neurogenic inflammation hypothesis may not apply to migraine. 相似文献
48.
A. G. Vologdin O. K. Vlasova L. I. Prikhod’ko 《Journal of Communications Technology and Electronics》2007,52(10):1100-1103
The spatial correlation properties of the group path and the group-delay time of a radio signal leaving a random plane-layered reflecting medium similar to the ionosphere are considered. The spatial-correlation distances for the group path lying in the incidence plane and oriented perpendicularly to this plane are obtained for various angles of propagation of a wave entering the medium. It is shown that, when a radio signal is scattered by isotropic irregularities of the medium’s permittivity, regular refraction results in anisotropic fluctuations of the signal’s characteristics and the degree of anisotropy grows with the sounding angle. 相似文献
49.
本文探讨了使用MSP430F5xxx实现ETC系统中实时HDLC编解码的方法.MSP430F5xxx是T1公司MSP430家族最新产品序列,采用先进的0.18工艺,1MIPS消耗的电流低到了惊人的160μA.同时,FSxxx产品都配备了高效灵活的DMA模块,对16bit数据进行搬移只需要2个时钟周期. 相似文献
50.