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41.
42.
Membrane expression of platelet calpain 总被引:1,自引:1,他引:1
Platelet calpain has many platelet substrates, including external membrane proteins. We thus investigated whether platelet calpain II was associated with platelet membranes in unstimulated and thrombin- activated platelets. A monospecific, goat polyclonal antibody was reared to purified platelet calpain II. Sixteen whole platelet lysates were found to contain 4.5 +/- 0.7 micrograms calpain antigen II per 10(8) platelets (mean +/- SEM) as determined by a competitive enzyme- linked immunosorbent assay. Using the dipeptide fluorogenic substrate, Suc-Leu-Tyr-MCA, 17 human platelet lysates contained 3.6 +/- 0.4 micrograms calpain activity per 10(8) platelets. Platelet calpain II was associated with the Triton X-100 insoluble platelet cytoskeletons from both unstimulated and thrombin-activated platelets. When compared with the total cell content of platelet calpain II, calpain antigen (10% to 13%) and calpain activity (24% to 28%) was associated with platelet cytoskeletons in unstimulated and thrombin-activated platelets, respectively. On immunoblot, the heavy chain (80 Kd) of calpain II was detected in platelet cytoskeletons. Subcellular fractionation studies on both unstimulated and thrombin-activated platelets, revealed that half of the total platelet calpain II antigen was associated with cytosol, and the other half was associated with the membrane fraction. Platelet calpain II was not seen on the surface of unstimulated, paraformaldehyde fixed platelets by immunofluorescence. However, on thrombin-activated platelets, rim immunofluorescence was seen, indicating that activated platelets externalize their calpain. This observation was confirmed by the finding that about 2,000 molecules per platelet of an 125I-anti-calpain II Fab' specifically bound to thrombin-activated but not unstimulated platelets. Both dibucaine (1 mmol/L) and platelet activating factor (1.86 mumol/L) in the absence of external Ca++, but not collagen (5 micrograms/mL) or ionophore A23187 (2.5 mumol/L) in the absence of external Ca++, were also able to externalize platelet calpain II antigen, as indicated by a similar level of specific 125I-anti-calpain II Fab'-platelet binding. These combined studies indicate that platelet calpain II is a major protein, comprising 2% of total platelet protein, a substantial portion of which is membrane-associated. When platelets are activated by thrombin and platelet activating factor, calpain II antigen also becomes present on the external platelet surface. 相似文献
43.
Human influenza A (H5N1) cases, urban areas of People's Republic of China, 2005-2006 总被引:1,自引:0,他引:1
Yu H Feng Z Zhang X Xiang N Huai Y Zhou L Li Z Xu C Luo H He J Guan X Yuan Z Li Y Xu L Hong R Liu X Zhou X Yin W Zhang S Shu Y Wang M Wang Y Lee CK Uyeki TM Yang W;Avian Influenza HN study Group 《Emerging infectious diseases》2007,13(7):1061-1064
We investigated potential sources of infection for 6 confirmed influenza A (H5N1) patients who resided in urban areas of People's Republic of China. None had known exposure to sick poultry or poultry that died from illness, but all had visited wet poultry markets before illness. 相似文献
44.
M. THORÉN T. RÄHN B. HALLENGREN P. H. KAAD K. O. NILSSON H. RAVN M. RITZÉN K. E. PETERSEN D. AARSKOG 《Acta paediatrica (Oslo, Norway : 1992)》1986,75(3):388-395
ABSTRACT. Eight children with Cushing's disease aged 6-18 years were treated with external radiation to the pituitary gland using 60 Co gamma radiation given with stereotactic technique. The dose given varied between 50 and 70 Gy. The observation time was 2.6 to 6.75 years. Seven children had a clinical remission with normal urinary Cortisol excretion. One child had insufficent effect of two irradiations and underwent bilateral adrenalectomy. In the patients in remission the growth velocity increased during the first year after treatment but growth retardation occurred again during the second year. Insufficient growth hormone secretion was demonstrated in all subjects. Two patients were given thyroxine substitution and three showed evidence for secondary hypogonadism. In conclusion, stereotactic pituitary irradiation was effective in normalizing the excessive glucocorticoid production in children with Cushing's disease. However, with the doses used, it was not possible to maintain a normal anterior pituitary function. 相似文献
45.
Walter JB; Brander C; Mammen M; Garboczi DN; Kalams SA; Whitesides GM; Walker BD; Eisen HN 《International immunology》1997,9(3):451-459
HLA-A2 heavy chain and beta 2-microglobulin were expressed in Escherichia
coli, and refolded in the presence of peptides derived from HIV-1 RT and
gag proteins. When recombinant HLA-A2 molecules were attached to cells
lacking HLA-A2, the cells became susceptible to lysis by HLA-A2-restricted
cytotoxic T lymphocyte (CTL) clones specific for peptides derived from RT
and gag proteins. Limiting dilution analyses of peripheral blood
mononuclear cells from HIV-1-infected individuals showed that the
recombinant HLA-A2 peptide complexes covalently immobilized on microspheres
stimulated the development of HLA-A2 peptide-specific CTL. Preformed
HLA-peptide complexes may provide an alternative to immunization procedures
that depend upon intracellular processing of antigen to elicit T cell
responses.
相似文献
46.
槐定碱的气相色谱测定法及其在兔体内的药代动力学 总被引:7,自引:0,他引:7
兔血浆中槐定碱的气相色谱测定条件:氮气、氢气和空气的流速分别为60,40和380ml/min。填充柱、进样室和检测室温度分别为190,280和300℃。内标物为槐胺碱,血浆中槐定碱浓度为3.0和10.0μg/ml时,测得回收率分别为103.6±2.4%(CV=2.34%)和101.5±6.5%(CV=6.35%)。线性范围为1~15/μg/ml。槐定碱在兔体内的药代动力学按二房室拟合,其混合参数值:α.0.0864 min-1;β.0.00932 min-1;Vc.1.19 L/kg;Varea.2.07 L/kg;Vdvv.1.99L/kg;Cl.19.3 ml/min·kg;MRT.103min。 相似文献
47.
48.
Eight oligonucleotides based upon regions of the small subunit 165 ribosomal RNA gene sequences were analysed against a background of their position within the molecule and their two-dimensional structure to rationalise their use in recognising Prevotetla intermedia and Prevotetla nigrescens . The 41 clinical isolates from both oral and respiratory sites and two reference strains were subjected to DNA-DNA hybridisation and multilocus enzyme etectrophoresis to confirm their identity. Alignment of oligonucleotide probes designated I Bi-2 to I Bi-6 (for P. intermedia ) and 2Bi-2 (for P. nigrescens ) with the 165 rRNA suggested that these probes lacked specificity or were constructed from hypervariable regions. A 52– mer oligonucleotide (designated Bi) retiably detected both species. Because of the high degree of concordance between the I 65 rRNAs of both species, it was necessary to vary the stringency of hybridisation conditions for detection of both species. Thus probe I Bi-I recognised P. intermedia while I Bi-l detected both P. intermedia and P. nigrescens at low stringency. However, under conditions of high stringency only P. nigrescens was recognised by probe 2Bi-I. These probes were highly specific and did not hybridise with DNA from the closety retated P. corporis , nor other periodontal pathogens such as Fuso-bacterium nucleatum, Actinobacillus actinomycetemcomit-ans , Treponema denticola and several pigmented species such as Prevotetla metoninogenica, P. denticola, P. loescheii, Porphyramonas osaccharolytica, Py. endodontalis, Py. gin-givalis, Py . levii, and Py. macacae . 相似文献
49.
50.
World Health Organization/World Organisation for Animal Health/Food Agriculture Organization HN Evolution Working Group 《Influenza and other respiratory viruses》2014,8(3):384-388
The divergence of the hemagglutinin gene of A/goose/Guangdong/1/1996‐lineage H5N1 viruses during 2011 and 2012 (807 new sequences collected through December 31, 2012) was analyzed by phylogenetic and p‐distance methods to define new clades using the pre‐established nomenclature system. Eight new clade designations were recommended based on division of clade 1·1 (Mekong River Delta), 2·1·3·2 (Indonesia), 2·2·2 (India/Bangladesh), 2·2·1·1 (Egypt/Israel), and 2·3·2·1 (Asia). A simplification to the previously defined criteria, which adds a letter rather than number to the right‐most digit of fifth‐order clades, was proposed to facilitate this and future updates. 相似文献