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141.
GP Rossi G Albertin S Bova AS Belloni F Fallo U Pagotto L Trevisi G Palù AC Pessina GG Nussdorfer 《Canadian Metallurgical Quarterly》1997,138(10):4421-4426
142.
G Gourdon P Dessen AS Lia C Junien H Hofmann-Radvanyi 《Canadian Metallurgical Quarterly》1997,40(2):73-77
The ultrastructural morphology of the interface region between the stria vascularis (SV) and spiral ligament (SL) was examined in the neonatal rat cochlea via transmission electron microscopy. At postnatal day (PND) 3, morphology of both basal cells and fibrocytes was simple and immature. Only a small number of fibrocytes was observed in the SL. Intercellular junctions between basal cells and fibrocytes, and between adjacent fibrocytes, were few. At PND 7, the number of fibrocytes increased, and more organelles appeared within their cytoplasm. From PND 11 to 14, nuclei of the basal cells appeared to be more spindle-shaped and contained more heterochromatin. The cytoplasm of the fibrocytes was pale, and a greater number of cytoplasmic vesicles and mitochondria emerged. More intercellular junctions were observed between basal cells and fibrocytes at the interface region and between fibrocytes in the SL. By PND 21, the morphology of basal cells and fibrocytes and their intercellular junctions appeared to be adult-like. These morphological observations correlate with previous reports on the functional maturation of the developing rat cochlea. 相似文献
143.
D Reddy AS Pollock SA Clark K Sooy RC Vasavada AF Stewart T Honeyman S Christakos 《Canadian Metallurgical Quarterly》1997,94(5):1961-1966
144.
H Chao ME Houston RS Hodges CM Kay BD Sykes MC Loewen PL Davies FD S?nnichsen 《Canadian Metallurgical Quarterly》1997,36(48):14652-14660
The most abundant isoform (HPLC-6) of type I antifreeze protein (AFP1) in winter flounder is a 37-amino-acid-long, alanine-rich, alpha-helical peptide, containing four Thr spaced 11 amino acids apart. It is generally assumed that HPLC-6 binds ice through a hydrogen-bonding match between the Thr and neighboring Asx residues to oxygens atoms on the {2021} plane of the ice lattice. The result is a lowering of the nonequilibrium freezing point below the melting point (thermal hysteresis). HPLC-6, and two variants in which the central two Thr were replaced with either Ser or Val, were synthesized. The Ser variant was virtually inactive, while only a minor loss of activity was observed in the Val variant. CD, ultracentrifugation, and NMR studies indicated no significant structural changes or aggregation of the variants compared to HPLC-6. These results call into question the role of hydrogen bonds and suggest a much more significant role for entropic effects and van der Waals interactions in binding AFP to ice. 相似文献
145.
Houston P.A. Blaauw C. Margittai A. Svilans M.N. Puetz N. Day D.J. Shepherd F.R. Springthorpe A.J. 《Electronics letters》1987,23(18):931-932
Double-heterojunction bipolar transistor structures in InP/GaInAs have been grown by low-pressure metal organic chemical vapour deposition. Good control of the Zn dopant in the GaInAs base layer was achieved, and devices with current gains up to 300 at current densities of 1.4kA/cm2 have been demonstrated. 相似文献
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The spin-spin relaxation time, T2, of skimmilk, sodium caseinate dispersions and milk ultrafiltrate was measured as a function of pH and temperature using pulse proton NMR. The T2 shows a maximum around pH = 5.2 for skimmilk, decreases with decreasing pH for sodium caseinate dispersions and is independent of pH for milk ultrafiltrate. For all systems studied T2 increases with temperature, but, the extent of increase depends on the system. It is concluded that the T2 of casein dispersions is mainly determined by factors determining the state of aggregation of the caseins. Apart from affecting the extent of aggregation of the casein particles, micellar calcium phosphate probably contributes also directly to the measured T2. 相似文献
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OBJECTIVE: To assess the outcome after transthoracic endoscopic sympathectomy (TES) for upper limb hyperhidrosis. DESIGN: Prospective cohort study. SETTING: District general hospital. SUBJECTS: Consecutive patients undergoing TES for upper limb hyperhidrosis over a fifteen month period. INTERVENTIONS: One-stage bilateral TES. MAIN OUTCOME MEASURES: Change in quality of life as shown by the Short Form-36 health assessment questionnaire. RESULTS: Sixteen patients (11 women and 5 men, median age 26 years) underwent operation without complications. At median follow-up of 6.2 months, symptomatic improvement was found in 26 of 32 limbs treated (82%). Truncal compensatory hyperhidrosis was reported by 13 patients but was severe in only three. There were significant improvements in social function (p = 0.01) and mental health (p = 0.025) as assessed by the SF-36. CONCLUSION: Despite a high incidence of compensatory hyperhidrosis, TES improved both the symptoms and overall quality of life in patients with upper limb hyperhidrosis. 相似文献