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921.
In a group of 71 patients and 22 donors the danger of infection transmission by infusion of cryopreserved peripheral blood progenitor cells to the patient and/or cross contamination of stored grafts was evaluated. No laboratory signs of active infection were found in 15 donors (13 related, 2 unrelated; 68%) and in 55 patients (77%). Active infection by herpesviruses was the most common (in 13 patients and 7 donors), hepatitis B being found in only one case. The cytomegalovirus IgG test was the most common marker of previous infection; it was found in 14 donors and 55 patients. The rate of clinically unsuspected infections in donors and patients including cases requiring immediate treatment among the patients group is relatively high and fully justifies the practice of prophylactic serological testing in the whole range of tests according to the European Blood and Marrow Transplantation Group and International Society for Hematotherapy and Graft Engineering in both autologous and allogeneic transplantations of hematopoietic stem cells. 相似文献
922.
Fluorescence competition assay for the assessment of ATP binding to an isolated domain of Na+, K(+)-ATPase 总被引:1,自引:0,他引:1
Kubala M Plásek J Amler E 《Physiological research / Academia Scientiarum Bohemoslovaca》2004,53(1):109-113
An equation allowing estimation of the dissociation constant for binding of a non-fluorescent ligand to the enzyme is presented that is based on the competitive replacement of the ligand by its fluorescent analog. We derived an explicit formula for the probe fluorescence intensity, which is suitable for nonlinear least-squares analysis. We used this formula to evaluate the binding of ATP to the large cytoplasmic loop of Na+,K(+)-ATPase. The estimated value of KD (6.2+/- 0.7 mM) is comparable with the results from other laboratories for similar constructs obtained by a different method. 相似文献
923.
924.
Preparative purification of soybean agglutinin by affinity chromatography and its immobilization for polysaccharide isolation 总被引:3,自引:0,他引:3
Franco-Fraguas L Plá A Ferreira F Massaldi H Suárez N Batista-Viera F 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,790(1-2):365-372
Optimized procedures for the affinity purification of soybean agglutinin (SBA) from soybean flour, and its further immobilization, were developed. Lectin purification on galactosyl-Sepharose yielded 44.5+/-3.5 mg of pure SBA/50 g of flour. To prepare SBA adsorbents, the lectin was immobilized onto 1-cyano-4-(dimethylamino)pyridinium tetrafluoroborate (CDAP) activated Sepharose with high yields (77%). Feasibility of the use of this improved SBA adsorbent for affinity purification of Streptococcus pneumoniae capsular polysaccharides from strain 14 (CPS-14) at laboratory scale was demonstrated. Using SBA-Sepharose adsorbent (7.0 mg lectin per ml), amounts of 6.3 mg of pure CPS-14 per cycle were produced, the adsorbent being reused up to four times without loss of capacity. 相似文献
925.
926.
I. Šafařík L. Ptáčková M. Koneracká M. Šafaříková M. Timko P. Kopčanský 《Biotechnology letters》2002,24(5):355-358
Ferrofluid-modified trypsin has been used for the detection and determination of selected xenobiotics that inhibit trypsin activity. The procedure is useful especially when colored samples or samples containing suspended solid impurities are to be assayed. Ferrofluid-modified trypsin was inhibited by Ag+ and Pb2+, selected dyes (safranin, thionin), bacitracin and 4-aminobenzamidine. Enzymes immobilized on magnetic particles can form a basis of new automated assay procedures for the determination of xenobiotics. 相似文献
927.
928.
Summary The distribution of microtubules inSaccharomyces cerevisiae was studied with the monoclonal antibody (mab) TU-14 against -tubulin. Immunoblotting and immunoprecipitation experiments with a strain overexpressing Tub2p confirmed that the mab TU-14 specifically recognized Tub2p. By immunofluorescence microscopy, the mab TU-14 attached to all known tubulin structures labelled with the standard polyclonal anti--tubulin antibody 206-1. In addition, the mab TU-14 revealed cortical patches in wild-type cells and an abundant network of fibres in the cortex of spheroplasts cultivated in nutrient medium. These cortical fibres seemed to be specific to spheroplasts and suggest that the accumulated Tub2p is predominantly associated with the plasma membrane. 相似文献
929.
Previously, we established experimental conditions allowing us to induce hypomethylation of tandem arrays of highly repetitive DNA sequences in the Nicotiana tabacum L. nuclear genome (M. Bezdk et al. 1991, Planta 184, 487–490). In this paper, we demonstrate that loci containing the highly repetitive sequences of the HRS60 family can maintain the induced hypomethylated state through protoplast regeneration, non-differentiated callus growth, and plant regeneration. The hypomethylation, induced with 5-azacytidine and monitored on these sequences, did not substantially alter the capacity of calli to produce plants. It can be concluded that, in contradistinction of multiple copies of transgenes or ectopic genes which are usually recognized as methylation targets, endogenous tandem repeats, such as the HRS60, present at 105 copies in the genome, can escape de-novo methylation.Abbreviation AzaC
5-azacytidine
This project was supported by the Grant Agency of the Academy of Sciences of the Czech Republic. We thank Ms. Libue Jedliková, Ms. Hana Suchánková, and Ms. Emilie Koudelková for technical assistance. 相似文献
930.
The preparation of internal reference material, NSC-21 Compost Vitahum, including its stabilization, homogeneity testing,
and evaluation of an interlaboratory comparison in which 19 laboratories took part using several analytical methods is described.
From the results of the intercomparison, consensus values were derived for the contents of Cd, Cu, Ni, Pb, and Zn, whereas
for As, Co, Cr, Fe, Hg and Mn, information values were derived. Bimodal distribution of the As and Cr results was obtained,
presumably because of incomplete dissolution of the elements from the matrix if insufficiently aggressive decomposition procedures
were employed. Some problems encountered were elucidated by application of neutron activation analysis (NAA) in its nondestructive
and destructive (radiochemical) modes. 相似文献