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91.
Herbert Olivecrona (1891-1980) singlehandedly founded Swedish neurosurgery. At the International Congress in Neurology in Bern in August, 1931, Harvey Cushing invited the cream of the world's medical society to a private banquet. Among the 28 specially invited guests was Herbert Olivecrona. At 40 years old, Olivecrona took his seat with pioneers such as Otfrid Foerster, Percival Bailey, Hugh Cairns, Geoffrey Jefferson, and Sir Charles Sherrington. This suggests that Cushing was impressed by the Swedish aristocrat's didactic deeds when he visited the Serafimer Hospital in Stockholm 2 years earlier. During the mid-1920's, the radiologist Erik Lysholm greatly improved the technique of ventriculography and, challenged by Olivecrona, his diagnostic neuroradiology became of superior quality. In the early 1930's, utilizing technical innovations of his own, Lysholm became a master at demonstrating and localizing posterior fossa tumors, which Olivecrona then operated on. Olivecrona's clinic became the mecca to which many scholars, thirsting for more knowledge, went on a pilgrimage. The international reputation of the clinic was founded, not on epoch-making discoveries, but by the resolute and practical application of methods already launched elsewhere and the exemplary organization that Olivecrona had established in collaboration with Lysholm. In spite of hardships and primitive working conditions, the clinic at the Serafimer Hospital gradually developed into the ideal prototype for a modern neurosurgical department. Olivecrona trained many colorful personalities who later were to lay the foundation for neurosurgery in their home countries; these included Wilhelm T?nnis of Germany, Edvard Busch of Denmark, and Aarno Snellman of Finland. Olivecrona was a true pioneer who made major contributions in practically all fields of conventional neurosurgery.  相似文献   
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Comments on L. R. Goldberg's (see record 1993-17546-001) history of the Big Five framework of personality traits and elaborated on its use. The reasons why industrial/organizational psychologists de-emphaszied the impact of personality on the job peformance in the late 1960s and 1970s and re-emphasized it in the 1980s are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 11, pp. 17–18, 23, November, 1993.  相似文献   
95.
SCG10 is a neuron-specific, membrane-associated protein that is highly concentrated in growth cones of developing neurons. Previous studies have suggested that it is a regulator of microtubule dynamics and that it may influence microtubule polymerization in growth cones. Here, we demonstrate that in vivo, SCG10 exists in both phosphorylated and unphosphorylated forms. By two-dimensional gel electrophoresis, two phosphoisoforms were detected in neonatal rat brain. Using in vitro phosphorylated recombinant protein, four phosphorylation sites were identified in the SCG10 sequence. Ser-50 and Ser-97 were the target sites for protein kinase A, Ser-62 and Ser-73 for mitogen-activated protein kinase and Ser-73 for cyclin-dependent kinase. We also show that overexpression of SCG10 induces a disruption of the microtubule network in COS-7 cells. By expressing different phosphorylation site mutants, we have dissected the roles of the individual phosphorylation sites in regulating its microtubule-destabilizing activity. We show that nonphosphorylatable mutants have increased activity, whereas mutants in which phosphorylation is mimicked by serine-to-aspartate substitutions have decreased activity. These data suggest that the microtubule-destabilizing activity of SCG10 is regulated by phosphorylation, and that SCG10 may link signal transduction of growth or guidance cues involving serine/threonine protein kinases to alterations of microtubule dynamics in the growth cone.  相似文献   
96.
This paper focuses on the hydrodynamics of third sound on a superfluid 3 He film. We solve the hydrodynamical equations in the limit of thick films with weak interaction with the substrate. The surface tension at the free interface is shown to have a large effect on the third sound velocity and on the attenuation for frequencies larger than 1Hz. In the case of a diffusely scattering substrate a ripplon-like dispersion relation is found for this frequency range.  相似文献   
97.
The transverse resonance approach to guided wave analysis is applied to shear horizontal (SH) wave propagation in periodically layered composites. It is found for SH waves that at high values of the guided wavevector β, the wave energy is trapped in the slower of the two media and propagates accordingly at the slower wavespeed. At low values of β, however, the modes demonstrate a clustering behavior, indicative of the underlying Floquet wave structure. The number of modes in a cluster is observed to correlate with the number of unit cells in the layered plate. New physical insights into the behavior of these systems are obtained by analyzing the partial waves of the guided SH modes in terms of Floquet waves. We show that the fast and slow shear waves in the periodically layered composite play an analogous role to the longitudinal and shear partial waves comprising Lamb waves in a homogeneous plate  相似文献   
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The biotransformation of oxazepam by Bifidobacterium bifidum was studied. The major metabolite was purified by chromatographic methods and found to be desmethyldiazepam using NMR, IR and other physicochemical data.  相似文献   
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