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151.
LE Hughes CM Clifford R Gresbrink LA Thomas JE Keirans 《Canadian Metallurgical Quarterly》1976,25(3):513-516
A rickettsia of the spotted fever group was isolated on three occasions from Ixodes pacificus in western Oregon. These isolations, and additional evidence furnished by complement fixation tests on guinea pigs inoculated with other Oregon ticks of this species, indicate that the association of this rickettsia with the Pacific Coast tick may be widespread. This is the first isolation of a spotted fever group rickettsia from I. pacificus. Because the Oregon isolates are mildly virulent for guinea pigs they resemble the Western U and Rickettsia montana strains of rickettsiae. However, preliminary evidence from cross-immunofluorescence tests of mouse antisera suggests the Tillamook and Grants Pass strains are antigenically different from all known spotted fever group agents. 相似文献
152.
A study was performed utilizing 3 mock eyes of different sizes to determine the precision and accuracy of 3 radiographic methods of localization of intraorbital foreign bodies. The Comberg method was found to be the most precise and accurate, next, the Sweet method, and then the modified spectacle frame method. However, the modified spectacle frame field expedient method of localization yielded a surprisingly high degree of accuracy in 2 of the 3 planes of reference, that is, mediolaterally and superointeriorly. A more accurate field expedient type of device which will permit greater accuracy in localization of intraorbital foreign bodies in the anteroposterior axis is currently under development. 相似文献
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The degeneration of the substantia nigra that characterises Parkinson's disease may cause an alteration in sensitivity of striatal dopamine receptors. The development of denervation supersensitivity has been held to be responsible for some of the effects of chronic levodopa therapy. The rotating rodent is an animal model commonly used to study the phenomenon of striatal dopamine receptor supersensitivity, and to investigate drugs which may prove to be beneficial in the treatment of Parkinson's disease. We have investigated as to whether long-term oral administration of levodopa to mice with unilateral destruction of striatal dopaminergic nerve terminals influences dopaminergic receptor denervation supersensitivity as judged by the circling response following systemically administered levodopa. It does not do so and the relevance of these findings to the treatment of Parkinson's disease is discussed. 相似文献
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BG Wallin G Sundl?f BM Eriksson P Dominiak H Grobecker LE Lindblad 《Canadian Metallurgical Quarterly》1981,111(1):69-73
Recordings of multiunit sympathetic activity were made in muscle branches of the peroneal nerve in 22 healthy subjects at rest in recumbent position. Nerve activity was quantitated in terms of burst incidence (number of pulse synchronous sympathetic bursts per 100 heart beats or per min). In a separate session, 4-45 months later, blood was drawn from an antecubital vein for noradrenaline analysis. Both sympathetic activity and plasma concentrations of noradrenaline varied widely between subjects and both parameters increased with age. There was a significant positive correlation between a subject's level of sympathetic activity and his plasma concentration of noradrenaline. It is suggested that overflow of transmitter from sympathetic terminals in muscles contributes significantly to plasma levels of noradrenaline at rest. 相似文献
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稀土改性固体超强酸SO42-/TiO2-MoO3-La2O3催化合成环己酮1,2-丙二醇缩酮 总被引:1,自引:0,他引:1
报道了以稀土改性固体超强酸SO42-/TiO2-MoO3-La2O3为多相催化剂,通过环己酮和1,2-丙二醇反应合成了环己酮1,2-丙二醇缩酮,探讨了SO42-/TiO2-MoO3-La2O3对缩酮反应的催化活性,采用正交试验法系统地研究了酮醇量比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明,稀土改性固体超强酸SO42-/TiO2-MoO3-La2O3是合成环己酮1,2-丙二醇缩酮的良好催化剂,在n(环己酮)∶n(1,2-丙二醇)=1∶1.6,催化剂用量为反应物料总质量的0.4%,环己烷为带水剂,反应时间1.0 h的优化条件下,环己酮1,2-丙二醇缩酮的收率可达88.8%。 相似文献