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991.
Quantitation of a cationic antimicrobial granule protein of human polymorphonuclear leukocytes by ELISA 总被引:1,自引:0,他引:1
The quantitation of CAP57, a highly hydrophobic, native cationic antigen of human polymorphonuclear leukocytes has been achieved using ELISA. An important feature determining the sensitivity and precision of the ELISA was the reduction of non-specific protein-protein binding, particularly in the inhibition assays, thus eliminating high backgrounds obtained with presently available methodology. Washing of the solid phase-bound antigen and blocking of the non-specific binding sites using a potassium phosphate buffer containing heparin largely contributed to this increased sensitivity. The inhibition assays were conducted using antigen concentrations over the range of 0.9-120 ng. The assay is highly specific and can be performed using monoclonal antibodies and polyclonal antibodies. Non-specific reactions were observed only when high concentrations of antigen (greater than 100 ng) were present in the inhibition mixture. The technique as described is extremely simple, highly reproducible and could be of value in the detection of cationic antimicrobial proteins in the clinical setting in the future. 相似文献
992.
Virgil Percec Gabriela Zipp Gary Johansson Uwe Beginn Martin Mller 《Macromolecular chemistry and physics.》1997,198(2):265-277
Synthesis and characterization of methacrylate-monofunctionalized crown ether compounds based on derivatives of 2-hydroxymethyl-1,4,7,10,13-pentaoxacyclopentadecane and 4′-hydroxymethyl-1,4,7,10,13-pentaoxabenzocyclopentadecane is described. By differential scanning calorimetry (DSC) and thermooptical analysis (TOA) it is shown that the synthesized compounds and their sodium triflate complexes exhibit columnar mesophases. 相似文献
993.
ERP modulations indicate the selective processing of visual stimuli as a result of transient and sustained spatial attention 总被引:2,自引:0,他引:2
Martin Eimer 《Psychophysiology》1996,33(1):13-21
Two experiments investigated selective processing as a result of transient and sustained visual-spatial attention. In Experiment 1, attention was cued on a trial-by-trial basis and event-related brain potentials were measured to stimuli preceded by valid, invalid, or neutral symbolic precues. Trial validity had only small effects on posterior PI and N1 components. At midline electrodes, an enhanced negativity for valid as compared with invalid trials was present, which appeared to reflect initial processing costs for invalid trials followed by an additional processing benefit for valid trials. Experiment 2 investigated whether these effects are specific for transient spatial attention by comparing transient and sustained attention conditions. No indication of early processing costs was found in the latter case. 相似文献
994.
Wolfgang Müller-Felber Klaus Küllmer Petra Fischer Carl-Detlev Reimers Stefan Wagner Ullrich Harland Martin Schmidt-Achert Dieter Pongratz 《Virchows Archiv : an international journal of pathology》1993,422(4):277-283
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
995.
996.
Lei C Dongqing Z Yeqing S Oaks MK Lishan C Jianzhong J Jie Q Fang D Ningli L Xinghai H Daming R 《European journal of human genetics : EJHG》2005,13(7):823-828
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease. 相似文献
997.
998.
Rees Mark I.; Andrew Martin; Jawad Sudad; Owen Michael J. 《Human molecular genetics》1994,3(12):2175-2179
Startle disease, or hyperekplexia, is characterized by an exaggeratedstartle reflex and neonatal hypertonla. An autosomal dominantform of the disorder Is associated with mutations In the samecodon of the 1 subunit of the inhibitory glycine receptor (GLRA1) resulting in the substitution of an uncharged amlno acidfor Arg271 in the mature protein. However, recessive transmissionIs seen in the mouse mutant spasmodic which resembles startledisease phenotypcially and is also associated with mutationsIn Glra 1. We have confirmed the finding of Arg271 mutationsIn individuals with startle disease in a UK family showing autosomaldominant transmission. In addition we describe an apparentlysporadic case, the offspring of a consanguineous mating, whoIs homozygous for a novel mutation (T1112A) in GLRA 1, whichresults In the substitution of asparagine for isoleucine atposition 244 of the mature protein. This suggests that humanstartle disease can display recessive as well as dominant inheritanceresulting from different mutations in GLRA 1. 相似文献
999.
Tim H.-M. Huang Diane Peckham Jacqueline R. Batanian Matthew B. Martin Melissa Kouba Charles W. Caldwell Judith H. Miles 《Clinical genetics》1994,46(4):299-303
We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation. 相似文献
1000.
A simple, quantitative method for assessing angiogenesis and antiangiogenic agents using reconstituted basement membrane, heparin, and fibroblast growth factor. 总被引:43,自引:0,他引:43
A Passaniti R M Taylor R Pili Y Guo P V Long J A Haney R R Pauly D S Grant G R Martin 《Laboratory investigation; a journal of technical methods and pathology》1992,67(4):519-528
BACKGROUND: Blood vessel growth is necessary for normal tissue homeostatis and contributes to solid tumor growth. Methods to quantitate neovascularization should be useful in testing biological factors and drugs that regulate angiogenesis or to induce a vascular supply to promote wound healing. EXPERIMENTAL DESIGN: An extract of basement membrane proteins (Matrigel) was found to reconstitute into a gel when injected subcutaneously into C57/BL mice and to support an intense vascular response when supplemented with angiogenic factors. RESULTS: New vessels and von Willebrand factor antigen staining were apparent in the gel 2-3 days after injection, reaching a maximum after 3-5 days. Hemoglobin content of the gels was found to parallel the increase in vessels in the gel allowing ready quantitation. Angiogenesis was obtained with both acidic and basic fibroblast growth factors and was enhanced by heparin. Several substances were tested for angiostatic activity in this assay by coinjection in Matrigel with fibroblast growth factor and heparin. Platelet-derived growth factor BB, interleukin 1-beta, interleukin-6, and transforming growth factor-beta were potent inhibitors of neovascularization induced by fibroblast growth factor. Tumor necrosis factor-alpha did not alter the response but was alone a potent inducer of neovascularization when coinjected with Matrigel and heparin. Consistent with the previously demonstrated importance of collagenase in mediating endothelial cell invasion, a tissue inhibitor of metalloproteinases that also inhibits collagenases was found to be a potent inhibitor of fibroblast growth factor-induced angiogenesis. CONCLUSIONS: Our assay allows the ready quantitative assessment of angiogenic and anti-angiogenic factors and should be useful in the isolation of endothelial cells from the capillaries that penetrate into the gel. 相似文献