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51.
52.
A mouse monoclonal anti human filaggrin antibody was found to bind keratohyaline granules of normal epidermis as well as of premalignant and malignant lesions in formalin-fixed tissue sections. In addition, an unexpected binding of this antibody with cells containing glycogen and other PAS positive substances was found, which could be abolished by adsorption of the anti-filaggrin antibody with glycogen or pretreatment of the sections with diastase. 相似文献
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Nocturnal periodic breathing at altitudes of 6,300 and 8,050 m 总被引:2,自引:0,他引:2
West J. B.; Peters R. M. Jr; Aksnes G.; Maret K. H.; Milledge J. S.; Schoene R. B. 《Journal of applied physiology》1986,61(1):280-287
Nocturnal periodic breathing was studied in eight well-acclimatized subjects living at an altitude of 6,300 m [barometric pressure (PB) 350-352 Torr] for 3-5 wk and in four subjects during one night at 8,050 m altitude (PB 281-285 Torr). The measurements at 6,300 m included tidal volume by inductance plethysmography, arterial O2 saturation by ear oximetry (calibrated by arterial blood samples), electrocardiogram (ECG), and electrooculogram. At 8,050 m, periodic breathing was inferred from the cyclical variation in heart rate obtained from a night-long ECG record. All subjects at 6,300 m altitude showed well-marked periodic breathing with apneic periods. Cycle length averaged 20.5 s with 7.9 s apnea. Minimal arterial O2 saturation averaged 63.4% corresponding to a PO2 of approximately 33 Torr, i.e., approximately 6 Torr lower than the normal value at rest during daytime. This was probably the most severe hypoxemia of the 24-h period. At 8,050 m altitude, the cycle length averaged 15.4 s, much longer than predicted by a theoretical model. Cyclical variations in heart rate caused by periodic breathing occurred in all subjects, but abnormal cardiac rhythms such as ventricular premature contractions were uncommon. The severe arterial hypoxemia caused by periodic breathing may be an important determinant of tolerance to these great altitudes. 相似文献
55.
We have found that the binding of pyridoxal-5′-phosphate to 6 primary amino groups leads to the inactivation of the enzyme. A preferential reaction of pyridoxal-5′-phosphate with the α-subunits of this enzyme can be demonstrated. The reactivity of the amino groups is influenced by various effectors. In the presence of ATP the inhibition of the ATPase activity is noncompetitive. 相似文献
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The urea concentration in the renal cortex ([RC]), liver ([L]) and skeletal muscle ([SM]) of non-diuretic Wistar rats was measured chemically and after an i.m. injection of 14C-urea and was compared with the plasma urea concentration ([P]). [L]/[P] and [SM]/[P] always equalled 1, irrespective of whether they were measured chemically or by means of radioactivity. [RC]/[P] was 2.81, again without any difference between chemical and radioactive measurement. The ratio of the chemically measured urea concentration in the renal cortex and plasma of mongrel dogs was 5.71, i.e. significantly higher than in rats (p less than 0.01). The intrarenal infusion of KCN, iodoacetate and ouabain did not alter it significantly (5.52, p greater than 0.05). Active transport, in whatever form, does not seem to be the cause of the high urea concentration in rat and dog renal cortex. 相似文献
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R H van der Pal P J Belde A P Theuvenet P H Peters G W Borst-Pauwels 《Biochimica et biophysica acta》1987,902(1):19-23
The initial rate of both Ca2+ and Mn2+ uptake is inhibited by ruthenium red to about the same extent as by equivalent concentrations of La3+. The inhibition of Ca2+ uptake, however, is relieved during further incubation with ruthenium red. On preincubating the cells with ruthenium red even a stimulation of divalent cation uptake can be found. Relieve of the inhibition of divalent cation uptake is accompanied by K+ efflux. Both ruthenium red and La3+ displace Ca2+ very effectively from binding sites at the cell surface. The inhibition of initial Ca2+ uptake is accompanied by a reduction in the binding of Ca2+. 相似文献