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The transverse carpal ligament (TCL) forms the volar boundary of the carpal tunnel and may provide mechanical constraint to the median nerve, leading to carpal tunnel syndrome. Therefore, the mechanical properties of the TCL are essential to better understand the etiology of carpal tunnel syndrome. The purpose of this study was to investigate the in vivo TCL stiffness using acoustic radiation force impulse (ARFI) imaging. The shear wave velocity (SWV) of the TCL was measured using Virtual Touch IQTM software in 15 healthy, male subjects. The skin and the thenar muscles were also examined as reference tissues. In addition, the effects of measurement location and ultrasound transducer compression on the SWV were studied. The SWV of the TCL was dependent on the tissue location, with greater SWV values within the muscle-attached region than those outside of the muscle-attached region. The SWV of the TCL was significantly smaller without compression (5.21 ± 1.08 m/s) than with compression (6.62 ± 1.18 m/s). The SWV measurements of the skin and the thenar muscles were also affected by transducer compression, but to different extents than the SWV of the TCL. Therefore to standardize the ARFI imaging procedure, it is recommended that a layer of ultrasound gel be maintained to minimize the effects of tissue compression. This study demonstrated the feasibility of ARFI imaging for assessing the stiffness characteristics of the TCL in vivo, which has the potential to identify pathomechanical changes of the tissue. 相似文献
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Kirsi-Marja Marnela Vince Varga Gábor Dibó Pekka Lähdesmäki 《Journal of neurochemistry》1987,48(4):1090-1092
To elucidate the position of the peptide bond in glutamyl-taurine this dipeptide was extracted from calf brain synaptic vesicles and subjected to paper electrophoresis. It was analyzed further in an automatic amino acid analyzer prior and subsequent to acid hydrolysis. Both alpha- and gamma-forms were found to be present in approximately equal amounts. 相似文献
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Dennis J. Vince 《CMAJ》1970,102(9):946-948
In eight adult dogs the main pulmonary artery was constricted to elevate the right ventricular peak systolic pressure to 50% of the peak aortic pressure at rest. The response of the right ventricle was assessed immediately, at 30 minutes and at six months. The right ventricle responded to acute systolic loading by complete compensation. After 30 minutes there was a reduction in the right ventricular outflow tract resistance. The cardiac output, heart rate and aortic pressure were maintained. The right ventricular systolic ejection period, end-diastolic pressure, peak pressure time, mean systolic pressure, right ventricular—main pulmonary artery mean systolic gradient, right ventricular work index, systolic work and outflow tract resistance were all increased.The right ventricle in the dog was shown to have an immediate capacity to compensate for systolic loading and retains this capacity for long periods of time. The ability to increase work is accomplished by adaptations in right ventricular physiology which increase right ventricular mean systolic pressures and prolong the right ventricular ejection period. 相似文献
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Dennis J. Vince 《CMAJ》1964,91(26):1345-1349
A retrospective analysis was made of the source of medical radiation received by 25 children who were investigated by cardiac catheterization techniques and followed in the Cardiac Outpatient Clinic of the Health Centre for Children, Vancouver General Hospital. The source of radiation was analyzed. The r dose per year received from plane films averaged 0.05 r, from cardiac fluoroscopy 6.7 r, and from catheterization and angiocardiography studies 1.58 r per year. In six of the 25 children, radiation doses to the thorax exceeded the LD50 for adult humans. In these six patients 95.8% of the radiation received was during cardiac fluoroscopy. Routine fluoroscopy for the radiological re-evaluation of pediatric patients with congenital heart disease should be replaced by plain chest radiographs. 相似文献
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Daphne Vince 《Planta》1967,75(4):291-308
Summary The ability of gibberellic acid (GA3) to prevent the light inhibition of stem elongation in peas was examined for several varieties under a wide range of irradiation conditions.A saturating dose of GA3 largely prevented the inhibitory effect of red light on total stem height in Duke of Albany (tall), Alaska (medium) and Meteor (dwarf) although a small, but statistically significant, effect persisted in all varieties after 3 days of light. The growth of the second internode was, however, markedly inhibited by red light even with a saturating dose of GA3. With gibberellin there was no difference between the effects of continuous red light and 15 minutes per day on height but the second internode was much shorter in the former treatment. The number of internodes present was the same in both cases and, therefore, the upper internodes in continuous light were as long or longer than in the 15-minute treatment. The number of internodes was only slightly fewer in darkness than in light so that, with GA3, the effect of red light was transient and only the growth of the lower internodes was inhibited. Without GA3 overall height was less in both red light treatments than in darkness for all three varieties.In blue light, on the other hand, there was no difference depending on whether height or internode length is considered, and even with a saturating dose of GA3 the growth rate remained depressed in continuous blue light. There was, however, some interaction between blue light and GA3.Red/far-red reversal experiments showed that in the varieties Alska and Duke of Albany the far-red stimulation of elongation persisted in the presence of a saturating dose of GA3 while for the dwarf variety Meteor there was a significant interaction between far-red and GA3.At least a quantitative difference was found between tall and dwarf peas in their response to light. Tall varieties showed a much greater effect of a prolonged exposure to blue and a smaller effect of a short exposure to red than dwarf varieties. Increasing the duration of exposure to red increasingly inhibited the growth of tall varieties. The medium variety Alaska grew to approximately the same height in continuous red and blue light. 相似文献
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Artificial acceleration of hatching in quail embryos 总被引:1,自引:0,他引:1
M A Vince 《Animal behaviour》1966,14(4):389-394
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The enantioselectivity and enantiomeric separation of five racemic piperidine-2,6-dione compounds, on the cellulose tris(3,5-dimethylphenyl carbamate) chiral stationary phase Chiralcel OD-CSP were investigated under the same chromatographic conditions. This class of drugs includes glutethimide, aminoglutethimide, cyclohexylaminoglutethimide, pyridoglutethimide, and phenglutarimide. The results revealed that chiral recognition and the binding sites of these drugs on the Chiralcel OD column are similar, regardless of the absolute configuration of the individual enantiomers. A possible chiral recognition mechanism(s) for this class of drugs and the CSP is presented. © 1994 Wiley-Liss, Inc. 相似文献