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101.
102.
Biological Properties of Interleukins   总被引:3,自引:0,他引:3  
Klaus  Bendtzen 《Allergy》1983,38(4):219-226
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We describe a family with at least seven living persons who are affected by an hitherto undescribed autosomal-dominant syndrome with variable expression, bearing close resemblance to the EEC syndrome and related disorders. The main manifestations are hypodontia and/or early loss of permanent teeth, ectrodactyly, obstruction of lacrimal ducts, onychodysplasia, and excessive freckling. We propose the acronym ADULT (acro-der-mato-ungual-lacrimal-tooth)-syndrome for this condition. © 1993 Wiley-Liss, Inc.  相似文献   
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The effect of low external Na+ concentrations on the light-induced K+ release from crayfish photoreceptor cells was tested by labelling intracellular K+ with the isotope86Rb. The amount of isotope released per light stimulus is roughly proportional to the external Na+ concentration if the osmolarity is kept constant by replacing Na+ with Tris, choline or sucrose. When sucrose is used to replace the depleted Na+ the light-induced K+ release is a linear function of the external Na+ concentration and is reduced by approx. 95% at an external Na+ concentration of 5 mmol/l. For choline and Tris substitutions the relationships are less clear but at Na+ concentrations 56 mmol/l it seems that in comparison with sucrose the light-induced K+ release is smaller in a Tris solution and larger in a choline solution. It is suggested that the light-induced K+ release is due mainly to an activation of voltage sensitive K+ channels.  相似文献   
107.
Previous in vivo studies have shown that the immunsuppressive peptide cyclosporin A (CsA) selectively suppresses antibody responses to nonmitogenic T-independent (TI-2) antigens, but not those to mitogenic (TI-1) antigens. This report demonstrates that in vitro CsA suppresses the polyclonal proliferative response of B cells to anti-Ig (anti-mu) antibodies at 300-400 fold lower doses than are required to inhibit B cell proliferation induced by lipopolysaccharide. Since the proliferative response to anti-mu requires neither T cells nor macrophages, it is concluded that CsA has a direct inhibitory effect on the B cells responding to this mitogen. The data support the concept that the B cells responding to TI-2 antigens are contained within the population which is stimulated polyclonally by anti-mu, and that lipopolysaccharide stimulates a distinct B cell subpopulation. They do not, however, exclude the possibility that anti-mu and lipopolysaccharide stimulate the same B cell population via two biochemically distinct triggering mechanisms, one of which is CsA-sensitive and the other CsA-resistant.  相似文献   
108.
Leu-19 antigen, which seems to be identical with neural cell adhesion molecule (N-CAM), plays a major role in the innervation of muscle cells, and in adult muscle appears after denervation and during regeneration of muscle fibres, where it acts as part of a signalling system increasing the probability of re-innervation. This combined enzyme-histochemical and immunohistochemical study examined whether this signalling process was regulated in a uniform or differential pattern for type 1 and type 2 muscle fibres. The subscapular nerve of 18 rabbits was transsected with subsequent complete denervation of the supraspinatus muscle. Leu19 and N-CAM immunohistochemistry was performed 2 to 64 days after surgery. Whereas in normal muscle there are virtually no Leu-19/N-CAM positive muscle fibres; from day 2 after denervation an increasing proportion of fibres expressed Leu-19/N-CAM, prior to any neurogenic atrophy. In the early stage of denervation Leul9/N-CAM expression was confined to type 1 fibres. After 11 days nearly all fibres were Leul9/N-CAM positive irrespective of their fibre type. Sixty-four days after denervation type 1 fibres became Leu19/N-CAM negative, while atrophic type 2 fibres showed intensive staining. Thus, expression of Leu-19 antigenity is differently regulated in both fibre types.  相似文献   
109.
Summary Clinical and postmortem findings in a female infant, suffering from Leigh's disease and cardiomegaly are described. The cardiac enlargement was due to symmetrical thickening of both ventricular walls and the septum. On light microscopy a widespread fibre disarray with a slight predilection for the ventricular septum was observed. Ultrastructural changes included an extreme reduction in the number of myofibrils and an excess of mitochondria. Abnormalities of the mitochondrial structure with tubular and myelinic transformation of the cristae suggested that a mitochondriopathy is responsible for the cardiomegaly in Leigh's disease.Dedicated to Prof. Dr. Waldemar Hort on the occasion to his 60th birthday  相似文献   
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