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991.
E Plassart-Schiess A Gervais B Eymard A Lagueny J Pouget JM Warter M Fardeau TJ Jentsch B Fontaine 《Canadian Metallurgical Quarterly》1998,50(4):1176-1179
Autosomal-dominant and -recessive myotonia congenita are caused by mutations in the skeletal muscle voltage-gated chloride channel gene (CLCN1). We searched for mutations in this gene in 20 unrelated families with myotonia congenita. We identified 11 different mutations in 10 families. Two of five new mutations (Ala313Thr and Ile556Asn) were both autosomal recessive and dominant with either reduced penetrance or incomplete dominance. Mutations in the CLCN1 gene do not therefore necessarily behave in a classic Mendelian manner. 相似文献
992.
Pediocin PA-1 bound to anionic lipid vesicles with saturated or unsaturated fatty acid chains in a lipid concentration-dependent fashion. Little change in binding parameters was observed for zwitterionic lipid vesicles. Decreasing the anionic lipid content of the vesicles gave a higher relative dissociation constant for the peptide-lipid interactions and further supports the electrostatic interaction model of binding. 相似文献
993.
In this article we evaluate current models of language processing by testing speeded classification of stimuli comprising one linguistic and one nonlinguistic dimension. Garner interference obtains if subjects are slower to classify attributes on one dimension when an irrelevant dimension is varied orthogonally than when the irrelevant dimension is held constant. With certain linguistic–nonlinguistic pairings (e.g., Experiment 1: the words high and low spoken either loudly or softly), significant Garner interference obtained when either dimension was classified; this indicated two-directional crosstalk. With other pairings (e.g., Experiment 3: spoken vowels and loudness), only the nonlinguistic dimension (e.g., loudness) displayed interference, suggesting unidirectional crosstalk downstream from a phonemic/graphemic level of analysis. Collectively, these results indicate the interaction can occur either within or across levels of information processing, being directed toward either more advanced or more primitive processes. Although poorly explained by all current models of language processing, our results are strikingly inconsistent with models that posit autonomy among levels of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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996.
D David M Naito EL Michelson J Morganroth TJ Mardelli T Blenko 《Canadian Metallurgical Quarterly》1981,48(3):468-472
Simultaneous hemodynamic and echocardiographic recordings were used to demonstrate mechanical atrial alternans during programmed atrioventricular (A-V) pacing in five open chest dogs. Each animal was studied in two stages, first with the A-V conduction system intact (phase I) and later after the experimental induction of complete A-V block (phase II). Atrial alternans was demonstrated during rapid atrial stimulation at cycle lengths ranging from 250 to 120 ms. During phase I, rapid atrial pacing resulted in complex combinations of variable A-V conduction disturbances with superimposed atrial and ventricular alternans. During phase II, atrial alternans could be observed during a programmed prolonged pause in ventricular activity. It is anticipated that this method will facilitate recognition of atrial alternans in various clinical situations and shed further light on its possible hemodynamic significance. 相似文献
997.
Frank T. Buckley Colin H. Marks 《Journal of Wind Engineering & Industrial Aerodynamics》1979,4(2):133-148
A wind-tunnel investigation was conducted to determine the effectiveness of boundary-layer control on the cab of a tractor to reduce the aerodynamic drag on a tractor-trailer truck. Tests were performed with suction alone, blowing alone, and the combination of suction and blowing. Significant drag reductions were found, even after accounting for the power required to operate the boundary-layer-control system.Feasibility studies were performed which assumed use of engine cooling airflow as a blowing source and of a separate system with combined suction and blowing. The maximum reduction in the net wind-averaged drag coefficient was found to be 21.9% for the situation involving use of engine cooling airflow with the fan-on. Though substantial, the power savings afforded by boundary-layer control were not significantly different from those afforded by passive means designed to produce similar effects on the flowfield or from declutching the fan instead of using it as a blowing power source. 相似文献
998.
SA Plotkin TJ Wiktor H Koprowski EI Rosanoff H Tint 《Canadian Metallurgical Quarterly》1976,103(1):75-80
The records of 340 patients treated surgically over the 20 year period 1950 through 1969 at this clinic for primary epidermoid carcinoma of the anterior two-thirds of the tongue were reviewed to evaluate the effectiveness of elective versus therapeutic radical neck dissection in their treatment. There has been a change in the clinical presentation of this disease, with more people presenting at an earlier stage, with a smaller primary lesion and fewer cervical node metastases. The over-all survival rate has shown a marked improvement to 69 per cent at five years. The proportion of women afflicted has increased. The status of the cervical nodes is a major prognostic factor, the determining five year survival rate being reduced from 78 to 26 per cent if the nodes are metastatically involved. It cannot be directly proved that removal of occult metastasis to the neck by elective radical neck dissection before nodes are clinically detectable leads to a better survival rate partly because the two groups being compared are selected and not randomly assigned. However, the marked tendency for carcinoma of the tongue to metastasize regionally at some time in its course, the significant error in clinical evaluation of the neck, the significant conversion of clinically negative nodes to positive in patients not treated with radical neck dissection, the poor prognosis after treatment of conversion from clinically negative into positive and the fact that more than half of the deaths are due to uncontrolled disease of the neck alone, make us strongly favor the principle of elective radical neck dissection to enhance the survival time in the group of patients without clinical evidence of nodal involvement. With current surgical expertise, the mortality and morbidity rates of simultaneous radical neck dissection are low, and the potential benefit of the procedure outweighs its potential risks. Obviously, elective radical neck dissection, if beneficial, would most likely be so in patients with the highest likelihood of having occult metastasis. 相似文献
999.
Purification of rat liver nuclear protein kinase NII 总被引:2,自引:0,他引:2
Rat liver nuclear protein kinase activity (NII), which is eluted from DEAE-Sephadex columns, has been purified approximately 1500-fold from solubilized nuclear protein. The method of purification involved chromatography of protein eluted from DEAE-Sephadex successively on phosvitin-Sepharose, mixed histone-Sepharose, and histone H2b-Sepharose followed by gel filtration on Sephadex G-200. Resulting preparations are homogeneous by polyacrylamide gel electrophoresis. The enzyme consists of three polypeptides with molecular weights of 42,000 (alpha), 39,000 (alpha'), and 26,000 (beta) which are present in the ratio 1:1:2 indicating that the enzyme has a minimum tetrameric subunit composition of alphaalpha'beta2. The molecular weight and s20,w of the purified enzyme were 123,000 and 7.0, respectively, as determined by sucrose density gradient centrifugation in 0.4 M NaCl. The enzyme has maximal activity with phosvitin as substrate and is not stimulated by 10(-5) to 10(-4) M cAMP or cGMP using H2b as substrate. 相似文献
1000.