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31.
The aim of this study was to determine if cephalometric measurement differences occurred between two groups of similarly aged female adolescents which differed with respect to their diagnoses of temporomandibular joint disc position on magnetic resonance images (MRI). One group consisted of 17 female adolescents exhibiting complete bilateral disc displacement affecting the temporomandibular joints (TMJ), while the second group of 17 female adolescents was diagnosed as having bilateral normal disc position on MRI. Independent sample t-tests identified statistically significant differences in cephalometric measurements between the two groups, but no age difference between the two groups was evident. The group with bilateral total disc displacement exhibited the following significant angular differences from the group with normal disc position: an increased mandibular and palatal plane relative to sella-nasion; posterior rotation of the mandible as illustrated by an increased angle between the posterior border of the mandibular ramus and sella-nasion; and a decrease in Rickett's facial axis. Significant differences in linear cephalometric variables were also evident between the two groups. Total posterior facial height and ramus height were reduced in the totally disc displaced group. Furthermore, a slight increase in the middle anterior facial height was noted, with a decrease in the posterior cranial base vertical height in the totally disc displaced group. 相似文献
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J Grétarsdóttir E Forssell Aronsson L Jacobsson O Hafsteinsdóttir S Holmberg L Hafstr?m S Lindegren B Karlsson L Lindholm S Mattsson 《Canadian Metallurgical Quarterly》1994,21(8):1017-1021
A monoclonal antibody, C215, was first internally labelled with 75Se-methionine and then labelled with 125I. The biodistribution of the dual-labelled [125I][75Se]C215 was studied in tumour-bearing nude mice killed 3 days after injection. The biodistribution of the dual-labelled [125I][75Se]C215 was compared with the biodistribution of single-labelled [131I]C215 and [75Se]C215. Iodine-labelled antibodies seem to be damaged during iodination, affecting the disappearance rate and tumour uptake. There were no signs of dehalogenation of circulating antibodies or antibodies taken up in the tumour. 相似文献
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Å. Karlsson 《Journal of Low Temperature Physics》1969,1(1):59-64
De Haas-van Alphen frequencies not previously reported have been measured for -PdIn and -CuZn. The results for PdIn suggest a reinterpretation of some of the previous results and offer an explanation of a previously unexplained set of de Haas-van Alphen frequencies in PdIn and AgZn. A recent nonlocal pseudo-potential model by Taylor can account for the experimental results reported here as well as the earlier data.National Research Council of Canada Postdoctorate Fellow. 相似文献
36.
Sven-Erik Karlsson 《Thin solid films》1985,124(1):1-2
The reliability of GaAs microwave devices is directly related to the integrity of Schottky and ohmic contacts for Schottky barrier devices and metal/semiconductor field effect transistor devices. The interface analysis of these device structures using surface analysis techniques has become extremely important in the study of the degradation of these devices. The research reported here focuses on three different metallic systems, namely Au/In, Au-12 wt.% Ge and Ni/AuGe, for both Schottky and ohmic contacts. The three metallic systems were evaporated onto 〈100;〉- oriented GaAs substrates (ND=3×1017cm-3) in an ultrahigh vacuum system. These samples were thermally aged by keeping them at 150°C for 500h. Current-voltage and capacitance-voltage measurements were made on as-deposited and thermally aged samples. The ideality factor decreased in all the samples. There was an apparent large increase in barrier height in AuGe/GaAs and Ni/AuGe/GaAs Schottky diodes. There was an insignificant change in the contact resistivity of ohmic contacts after thermal aging.The changes in the electrical characteristics of these device structures are explained on the basis of the formation of an oxide layer after thermal aging. A comparison of the Auger depth profiles of the as-deposited and the thermally aged samples substantiates the electrical observations. However, Au/In/GaAs Schottky diodes do not show the existence of an oxide layer at the interface. The out-diffusion of indium to the surface might have removed the oxygen from the interface to result in an Au-GaAs interface in the thermally aged sample. A slight increase in the barrier height of this sample is due to the Au-GaAs interface rather than the In-GaAs interface. 相似文献
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甲磺酸倍他司汀经氧瓶燃烧后用吸收液吸收,结构中的硫氧化成硫酸根,采用离子色谱法测定,并根据甲磺酸倍他司汀化学式的计量关系求出样品中有效药物的含量.结果硫在0.02～60 μg·m<'-1>浓度范围内线性关系良好,平均回收率为98.8%,RSD为0.15%. 相似文献
39.
Karlsson R Kurczy M Grzhibovskis R Adams KL Ewing AG Cans AS Voinova MV 《Nanoscale research letters》2011,6(1):421
In this study we report a physical analysis of the membrane mechanics affecting the size of the highly curved region of a lipid nanotube (LNT) that is either connected between a lipid bilayer vesicle and the tip of a glass microinjection pipette (tube-only) or between a lipid bilayer vesicle and a vesicle that is attached to the tip of a glass microinjection pipette (two-vesicle). For the tube-only configuration (TOC), a micropipette is used to pull a LNT into the interior of a surface-immobilized vesicle, where the length of the tube L is determined by the distance of the micropipette to the vesicle wall. For the two-vesicle configuration (TVC), a small vesicle is inflated at the tip of the micropipette tip and the length of the tube L is in this case determined by the distance between the two interconnected vesicles. An electrochemical method monitoring diffusion of electroactive molecules through the nanotube has been used to determine the radius of the nanotube R as a function of nanotube length L for the two configurations. The data show that the LNT connected in the TVC constricts to a smaller radius in comparison to the tube-only mode and that tube radius shrinks at shorter tube lengths. To explain these electrochemical data, we developed a theoretical model taking into account the free energy of the membrane regions of the vesicles, the LNT and the high curvature junctions. In particular, this model allows us to estimate the surface tension coefficients from R(L) measurements. 相似文献
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