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32.
A light-weight nonmagnetic, nonconductive instrument has been devised for use with magnetic resonance imaging, computerized tomography, and digital subtraction imaging for work in the field of epilepsy, brain tumors and vascular lesions. The apparatus' main characteristic is its ability to use optionally either the lateral orthogonal or the spherical-radial approach. 相似文献
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Netherlands Heart Journal - 相似文献
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Interaction between the Effects of Inside and Outside Na and K on Bullfrog Skin Potential 总被引:2,自引:1,他引:1
Daniel E. Leb Charles Edwards Barry D. Lindley T. Hoshiko with the technical assistance of James A. Dugan 《The Journal of general physiology》1965,49(2):309-320
The composition of the solution bathing one border of the isolated frog skin affects the response of the potential across the skin to changes in the composition of the solution bathing the opposite border. Increasing the K concentration of the inside (corium) bathing solution decreased the sensitivity of the potential to a change in outside Na concentration. Decreasing the outside Na concentration decreased the sensitivity of the potential to a change in inside K concentration. Increasing the total ionic strength of the outside bathing solution or of both bathing solutions decreased the sensitivity of the potential to a change in outside Na concentration. 相似文献
37.
EVOLUTIONARY AND GEOGRAPHIC TRENDS IN ADAPTIVE WOOD ANATOMY IN ERIASTRUM DENSIFOLIUM (POLEMONIACEAE)
Anatomical features of Eriastrum densifolium populations in southern California show variation that correlates well with ecological setting and geographical distribution. Vessel element size and density in shoots suggest strong adaptation among different subspecies to efficient water movement in different habitats. Indices of mesomorphy, devised by Carlquist to indicate relative adaptivity of wood, likewise show considerable variation among populations, suggesting that different subspecies have anatomical components that can define them. Relationships among the five subspecies of E. densifolium may be explored through MI value relationships. 相似文献
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Anton Pauw Sunshine A. Van Bael Halton A. Peters Steven D. Allison José L. C. Camargo Miguel Cifuentes-Jara Aurlstela Conserva Teresa Garcia Restom Tamara Heartsill-Scalley Scott A. Mangan Gabriela Nunez-lturri Elsie Rivera-Ocasio Mark Rountree Susanne Vetter Carolina Volkmer de Castllho 《Biotropica》2004,36(3):410-413
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Hybrid formation within the genus Leishmania? 总被引:4,自引:0,他引:4
Leishmanial organisms isolated from a desert rodent (Psammomys obesus) and a feral dog (Canis familiaris) in the Eastern Province of Saudi Arabia were isoenzymically distinct from Leishmania major and L. arabica, organisms usually associated with human and wild animal cutaneous leishmaniasis in this area. Further examination of isoenzyme banding patterns of cloned populations of these organisms, together with karyotyping using orthogonal field alternation gel electrophoresis and the use of highly specific kinetoplast DNA probes, has produced evidence suggesting that these organisms isolated from the dog and the rodent are hybrids of L. major and L. arabica. 相似文献
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Basic mechanical properties of retina in simple elongation 总被引:4,自引:0,他引:4