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941.
Accuracy of an anthropometric estimate of the muscle and bone area in a transversal cross-section of the arm 总被引:3,自引:0,他引:3
F L de Koning R A Binkhorst J M Kauer H O Thijssen 《International journal of sports medicine》1986,7(5):246-249
To standardize the maximal static force (Fo) of the arm flexors, the accuracy of an anthropometric method for estimating the mid-arm cross-sectional muscle and bone area (MBA) was investigated. This was done by comparing the anthropometrically determined area (MBA.A) with the area measured by means of computerized tomography (MBA.S). In the same way, the accuracy of Heymsfield's equations (Heymsfield et al., 1982) for predicting MBA (MBA.H) from anthropometric measures was tested. MBA.A was significantly larger than MBA.S, the relative difference increasing with the thickness of the subcutaneous fat layer. This difference was attributed to a 27% underestimation of the fat layer thickness as measured with the skinfold caliper. Women being fatter than men, this caused the standardized maximal static force (Fo/MBA) to be lower in women than in men. MBA.H was 12% smaller than MBA.S. This may have been due to a difference in the way of measuring the arm circumference between the present authors and Heymsfield et al. 相似文献
942.
The averaged evoked compound action potentials (AECAPs) were recorded from the ipsilateral pyramidal tract of awake, unrestrained cats before, during, and after continuous electrical stimulation of the cerebral cortex via chronically implanted activated iridium or platinum-30% iridium (Pt30%Ir) microelectrodes. After stimulating 24 h at 20 pulses per second (pps), using charge-balanced, 200-microseconds pulse pairs of 40 to 80 microA (400 to 800 microC/cm2, 8 to 16 nC/phase (ph), 2 to 4 A/cm2), there was a transient elevation of the threshold of the early (direct) and of the alte (transynaptic) components of the AECAP. After cessation of continuous stimulation at 80 microA, the threshold of the early component of the AECAP remained elevated for as long as 24 h and the late component as long as 4 days, indicating significant but reversible depression of the electrical excitability of cortical neurons close to the microelectrodes. In three cats stimulated 23 h/day for 1 week, the AECAP also recovered to their prestimulus threshold. In contrast, pulsing for 24 h at 320 microA (3200 microC/cm2, 64 nC/ph, 16 A/cm2) produced marked elevation of the threshold of the AECAPs which was not reversed by 7 to 12 days after termination of intracortical stimulation. The electrical excitability of neurons adjacent to (unpulsed) microelectrodes 2 mm from the pulsed electrode was not affected. The observations reported here, in conjunction with the histologic results reported in the companion paper, indicate that both the Pt30%Ir and the iridium microelectrodes can be operated safely at currents to at least 80 microA, charge/ph of 16 A/cm2, and a charge density of 800 microC/cm2 X ph. However, on the basis of the electrophysiologic criteria, both types appear to be unsafe when pulsed at 320 microA (64 nC/ph, 3200 microC/cm2 X ph, 16 A/cm2). 相似文献
943.
M F Monge-Strauss F Mikol 《Revue d'électroencéphalographie et de neurophysiologie clinique》1986,16(4):361-369
Non-invasive transcranial Doppler US investigation in adult patients was first described by Aaslid et al. (1982). The apparatus consists in a 2 MHz bidirectional pulsed Doppler with spectrum analyser. Middle and anterior cerebral arteries were insonated by transtemporal exploration, basilar artery by occipital foramen. The criteria of identification were: position and angulation of the probe, direction of the flow, depth of sample volume. The authors present a first series of 31 patients, all with cervical CW Doppler and B-mode Echo. The percentage of identification was: MCA 72%; ACA 69%; BA 54%. Some clinical cases are illustrated. The interest of the method is emphasized in spite of constraints depending on probe position and anatomical variability of the circle of Willis: ambulatory and non-invasive methods; assessment of intracranial blood flow in various conditions: cerebral ischemia and infarction, intracerebral angioma; complementarity with other non-invasive and non-expensive techniques: EEG and cervical US investigation. 相似文献
944.
945.
We examined the relationships between the relaxation mediated by beta-adrenoceptor and either the associated cyclic AMP production or the activation of cyclic AMP-dependent protein kinase (A-PK) in canine saphenous and portal veins. In the saphenous vein constricted with methoxamine, isoproterenol caused concentration-dependent relaxation (maximum relaxation 92.7%), and concomitant increases in cyclic AMP and A-PK activity ratio (from 52.8 to 73.5%). The portal vein was only slightly relaxed by isoproterenol (14.7% in the longitudinal strips) after constriction with methoxamine, while cyclic AMP and A-PK activation increased significantly. Isoproterenol markedly activated A-PK of the portal vein after KCl constriction (from 52.6 to 74.6%) but the maximum relaxation was only slight (13.3%). The portal vein also showed a smaller relaxation response to either forskolin or dibutyryl cyclic AMP than the saphenous vein. These results indicated that the relationship between the relaxation response to isoproterenol and either cyclic AMP production or A-PK activation was different in the saphenous and portal veins. 相似文献
946.
Prolidase was highly purified from human liver and erythrocytes. NaDodSO4/acrylamide gel electrophoresis revealed that these preparations contained a major protein with MW = 56,000. The mass of prolidase was estimated on gel filtration to be MW = 97,000, for both enzyme preparations. A monoclonal antibody was raised against the liver enzyme and a specific antiserum against the erythrocyte enzyme. The monoclonal antibody (EP-2) recognized prolidase from erythrocytes and liver, in equal proportions. The antiserum also recognized the enzyme from erythrocytes and liver. Immunoprecipitation studies with these antibodies suggested only a single species of prolidase in erythrocytes and liver. Using an immobilized monoclonal antibody (EP-2) as an immunoadsorbent, prolidase was partially purified from crude extracts, and the protein of the partially purified enzyme was identified by immunoblotting using antiserum. A protein band with a MW = 56,000 was demonstrated specifically when crude extracts from the liver and erythrocytes were examined using NaDodSO4/acrylamide gel electrophoresis. The subunit protein was absent in erythrocytes from a patient with prolidase deficiency. We propose that the absence of the subunit is one cause of the prolidase deficiency. 相似文献
947.
F. Ide K. Obara K. Enatsu K. Mishima I. Saito 《Journal of oral pathology & medicine》2005,34(3):187-189
Sclerosing mucoepidermoid carcinoma (SMEC) with eosinophilia is a rare but distinctive tumor usually affecting the thyroid. SMEC involvement of salivary gland is exceptional, with only six cases in the literature. We present here the first case of an intermediate-grade SMEC, arising from the intraoral minor salivary glands. A particularly interesting finding is the cytoplasmic accumulation of eosinophilic hyaline granules in carcinoma cells, similar to aberrant zymogen-like granules previously described in salivary sclerosing polycystic adenosis. 相似文献
948.
949.
Jennifer M Griffith James R Sorenson J Michael Bowling Tracey Jennings-Grant 《Health education & behavior》2005,32(5):613-626
The Enhancing Patient Prenatal Education study tested the feasibility and educational impact of an interactive program for patient prenatal genetic screening and testing education. Patients at two private practices and one public health clinic participated (N = 207). The program collected knowledge and measures of anxiety before and after use of the tool. Time in various prenatal visit activities was collected prior to and after the introduction of the education tool. Providers completed an assessment of their experiences with patients who had used the program. Results indicate that patient knowledge significantly increased from pre to post (p = .0001) with no increase in anxiety (p = .31). Time in clinic activities, including overall visit time, increased. A majority of providers indicated that the program disrupted clinic flow. This assessment suggests that the program increases patient knowledge and does not increase patient anxiety. However, challenges remain to using this program in a clinic setting. 相似文献
950.
Inflammation Research - . 相似文献