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971.
V Milosevi? S Velkovski B Brki? M Sekuli? M Lovren V Starcevi? WB Severs 《Canadian Metallurgical Quarterly》1996,53(6):369-375
Segmental zoster paresis (SZP) is the focal, asymmetrical neurogenic weakness which may occur in a limb affected by cutaneous zoster. We have summarized the features of this syndrome, based on a retrospective review of 8 personal and 96 published cases. Limb SZP becomes apparent in at least 3-5% of patients with cutaneous zoster, who are usually over the age of sixty and weak proximally (C5,6,7 or L2,3,4 innervated muscles). Functional motor recovery occurs in about 75% of cases, generally by 1-2 years. Limb weakness is probably due to a lesion of the ventral nerve root, in close proximity to the initiating dorsal ganglionitis. The electrodiagnostic findings, scarce in the literature, typically consist of absent compound sensory nerve action potentials in the involved limb, with less frequent reduction or loss of compound muscle action potentials. Fibrillations and positive sharp waves become detectable within 1-4 months in limb and related paraspinal muscles, decreasing or disappearing later. In addition to this radiculopathy, peripheral nerves may also occasionally become involved, manifest as mononeuropathies of the median, ulnar, long thoracic, recurrent laryngeal, and phrenic nerves. The zoster infection or consequent inflammatory response appears able to affect motor axons distally as well as proximally. 相似文献
972.
Hepatic and pancreatic effects of polyenoylphosphatidylcholine in rats with alloxan-induced diabetes
V Buko O Lukivskaya V Nikitin Y Tarasov L Zavodnik A Borodinsky B Gorenshtein B Janz KJ Gundermann R Schumacher 《Canadian Metallurgical Quarterly》1996,14(2):131-137
In neonatally allylestrenol treated animals in adult age a single benzpyrene treatment significantly decreases the female and significantly increases the male rat's sexual activity. Three month old females display the negative sexual behavioral effect of neonatal allylestrenol treatment less than the six month old ones. The benzpyrene treatment in adult age decreases the sexual activity of male rats. The experiments call the attention to the modifying effect of perinatal steroid treatments to similar exposure in adult age. 相似文献
973.
The results of a thermal engineering analysis of a bath furnace heated by natural gas with the surface area of the melting part equal to 303.3 m2 and equipped with six pairs of burners are presented. Practical recommendations are given for increasing the efficiency of the furnace. The data can be used for developing a mathematical model of heat transfer in a glass furnace.Translated from Steklo i Keramika, No. 3, pp. 9–11, March, 1996. 相似文献
974.
Neudorf E.G. Kiguel D.L. Hamoud G.A. Porretta B. Stephenson W.M. Sparks R.W. Logan D.M. Bhavaraju M.P. Billinton R. Garrison D.L. 《Power Systems, IEEE Transactions on》1995,10(3):1667-1675
There is an emerging recognition that utility investments and other decisions that affect electric service reliability should be explicitly evaluated on the basis of their cost and benefit implications. A cost-benefit approach that quantifies the reliability benefits of alternatives in terms of the reduction in costs resulting from unserved energy enables the evaluation of generation and transmission capacity additions on a consistent, economic basis. This approach has been applied to two utility case studies. In a case study for Pacific Gas and Electric Company, it was used to evaluate three options for maintaining reliability in a major load center-two involving local generation, and the third, a new 230 kV transmission connection. In a case study for Duke Power Company, the approach was used to evaluate alternative designs for proposed additions to a transmission station. This paper describes the methodology and presents the two utility studies 相似文献
975.
976.
B Amy de la Bretèque 《Canadian Metallurgical Quarterly》1995,116(4):271-272
The adolescent's breaking of the voice is the result of the substitution of the chest voice (or heavy mechanism) for the head voice (or light mechanism). In cases of late breaking, the voice is abnormally high-pitched and feeble, often with a distorted timbre, while the larynx is normal and pubescent. Such people are generally not fully aware of their voices' real nature. Therapy classically resorts to laryngeal manipulations, of which a new technique is put forward. Another therapeutic approach is based, on the one hand, on critical listening compared with a control male voice, thus enabling the subject to become aware of his own voice, and, on the other hand, on high intensity work which helps passing from head to chest voice. 相似文献
977.
Yu. B. Zudin 《Journal of Engineering Physics and Thermophysics》1995,68(2):193-196
Processes of heat transfer with periodically varying intensity on the surface of heated bodies of three typical geometries (plate, cylinder, sphere) are considered. The true heat transfer coefficient, which varies in time by the law of a periodic step function having two free parameters — amplitude and asymmetry, is specified on the heat transfer surface. Resultant relations are obtained for calculating the experimental heat transfer coefficient, which is the quantity measured in a traditional heat transfer experiment and used in applied calculations.Moscow Power Engineering Institute. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 68, No. 2, pp. 225–228, March–April, 1995. 相似文献
978.
Polarisation insensitive semiconductor optical amplifier withintegrated electroabsorption modulators
Koren U. Miller B.I. Young M.G. Chien M. Raybon G. Brenner T. Ben-Michael R. Dreyer K. Capik R.J. 《Electronics letters》1996,32(2):111-112
The authors demonstrate a 1.55 μm wavelength multiquantum well semiconductor optical amplifier, integrated with bulk layer electroabsorption modulators and passive waveguide beam expanders at the input and output ports. The device has a fibre to fibre gain of 9 dB, an extinction ratio of 15 dB per modulator, a spectral range >35 nm, and polarisation sensitivity <1 dB 相似文献
979.
980.