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1.
2.
M Koehler H Buba?a D Sońta-Jakimczyk E Guzikowska A Janik-Moszant M Wieczorek J Ho?owiecki 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1989,44(40-42):879-81, 884
Blasts phenotype was determined in 61 children with the acute lymphoblastic leukemia. Non-T-cell acute lymphoblastic leukemia was diagnosed in 51 children. Stages of blasts differentiation were determined with the aid of monoclonal antibodies set using alkaline phosphatase-anti-alkaline phosphatase technique. Blasts in 50 patients belonged to B subpopulation confirmed by the presence of panB CD19 and CD22 antigens. Common antigen was seen in 76.5% of the examined patients with non-T-cell acute lymphoblastic leukemia. Cases of non-T-cell acute lymphoblastic leukemia were divided into 8 subgroups depending on the antigens of B-cells differentiation. An identification of pre-B subgroups of the acute lymphoblastic leukemia indicates heterogenicity of the acute lymphoblastic leukemias in childhood and enables their classification into groups corresponding to the early stages of lymphoblasts maturation. 相似文献
3.
Danuta Dus Maciej Ugorski Wojciech Gorczyca Czeslaw Radzikowski 《Glycoconjugate journal》1989,6(3):355-365
125I-Wheat germ agglutinin (WGA) binding parameters of human urothelial cell lines of different grades of transformation (TGrll and TGrlll) were compared. The values of association constant (Ka) and the number of binding sites/cell for HCV29 (TGrll) cell line were about 3×106M–1 and over 4×107, respectively. Two TGrlll cell lines, HCV29T and Hu549 revealed lower values for Ka, and considerably higher numbers of binding sites/cell (about 3×108 and 2×108, respectively). Binding of125I-WGA to total cellular proteins resolved by SDS-PAGE and transferred to nitrocellulose showed multiple diffused bands in the range of 58–180 kDa. Some of these bands were characteristic for TGrll cells (124 kDa) or TGrlll cells (135 and 148 kDa).Abbreviations TGr
transformation grade
- WGA
wheat germ agglutinin
- sWGA
succinylated wheat germ agglutinin
- GlcNAc
N-acetyl-d-glucosamine
- BSA
bovine serum albumin
- SDS-PAGE
sodium dodecyl sulphate polyacrylamide gel electrophoresis 相似文献
4.
Ignacy Z. Siemion Artur Pdyczak Jerzy Trojnar Michakl Zimecki Zbigniew Wieczorek 《Peptides》1992,13(6):1233-1237
In connection with our discovery of a strong immunosuppressive activity of cyclolinopeptide A (CLA), we investigated immunosuppressive properties of antamanide and a number of its analogues, including symmetrical antamanide, and compared them with the activities of cyclosporin A and CLA. The peptides were investigated by using plaque forming cell (PFC), graft-versus-host (GvH), delayed type hypersensitivity (DTH), and autologous rosette formation cell (ARFC) tests. Antamanide and symmetrical antamanide exhibit an immunosuppressive activity lower than CLA. Linear antamanide fragments are also active. At higher concentrations of the latter peptides, toxic effects occur. 相似文献
5.
Characterization of a developmentally regulated perinatal myosin heavy-chain gene expressed in skeletal muscle 总被引:15,自引:0,他引:15
M Periasamy D F Wieczorek B Nadal-Ginard 《The Journal of biological chemistry》1984,259(21):13573-13578
A cDNA clone, labeled pFOD5, isolated from a fetal-rat skeletal-muscle cDNA library, has been characterized and found to contain sequences corresponding to a perinatal-specific skeletal myosin heavy-chain (MHC) mRNA. This MHC cDNA demonstrates a high degree of nucleotide- and amino acid-sequence conservation with other MHC genes, but its carboxyl-terminal peptide and 3'-untranslated region are highly divergent and specific for this gene. S1 nuclease mapping experiments have shown that the perinatal MHC gene represented by this cDNA clone is only transiently expressed during skeletal-muscle development. Perinatal MHC mRNA is first detected late in fetal life, reaches maximal levels of expression at the end of the first postnatal week, and is de-induced thereafter. Its levels are almost undetectable at 28 days of postnatal life. During fetal and early postnatal life, the expression of this perinatal gene in skeletal muscle overlaps with the expression of the embryonic MHC gene. After the first week of extrauterine life, this gene is coexpressed with two adult MHC genes. The transient expression of this perinatal MHC gene raises interesting questions about the physiological significance of the MHC transitions and offers an interesting model for the study of MHC gene regulation. 相似文献
6.
N,N′-Dicyclohexylcarbodiimide (DCCD) inhibits the activity of ubiquinol-cytochrome c reductase in the isolated and reconstitued mitochondrial cytochrome b-c1 complex. DCCD inhibits equally electron flow and proton translocation (i.e., the ratio is not affected) catalysed by the enzyme reconstituted into phospholipid vesicles. The inhibitory effects are accompanied by structural alterations in the polypeptide pattern of both isolated and reconstituted enzyme. Cross-linking was observed between subunits V (iron-sulfur protein) and VII, indicating that these polypeptides are in close proximity. A clear correlation was found between the kinetics of inhibition of enzymic activity and the cross-linking, suggesting that the two phenomena may be coupled. Binding of [14C]DCCD was also observed, to all subunits with the isolated enzyme and preferentially to cytochrome b with the reconstituted vesicles; in both cases, however, it was not correlated kinetically with the inhibition of the enzymic activity. 相似文献
7.
Maciej Zenkteler 《American journal of botany》1962,49(4):341-348
Zenkteler , Maciej . (U. Adam Mickiewicz, ul. Stalingradzka 14, Poznan, Poland.) Microsporogenesis and tapetal development in normal and male-sterile carrots (Daucus carota). Amer. Jour. Bot. 49(4): 341–348. Illus. 1962.—Meiosis and anther development proceed normally in fertile plants. Nine pairs of chromosomes are present at diakinesis and at metaphase I. The mature pollen grains possess 2 male gametes at the time of shedding; 80–92% of the pollen appears normal. A cross-shaped configuration at pachytene characteristic of a reciprocal translocation is present in the completely pollen-sterile plants indicating that one of the parents is homozygous for an interchange between 2 members of the chromosome complex. Chromosome bridges with fragments at anaphase I and anaphase II lead to aberrant chromosome distribution during meiosis. Complete microspore abortion is associated with a periplasmodium formation of the tapetum and anther wall deterioration. 相似文献
8.
Helmut Wieczorek Gabriele Wolff 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1989,164(6):825-834
1. | The electrophysiology of the sugar receptor in labellar taste hairs ofDrosophila melanogaster (Diptera) was investigated using 33 monosaccharides, oligosaccharides, glucosides, and amino acids which in calyptrate flies are known to bind to specific receptor sites or which may be assigned to specific receptor sites on the basis of structural criteria. |
2. | The pyranose site ofDrosophila is very similar to the pyranose site of the calyptrate flies: regarding monosaccharides of the pyranose type three adjacent equatorial hydroxyl groups (C-2, C-3, C-4) seem to be important for stimulating effectiveness. On the other hand, it exhibits a more rigid stereospecificity with regard to the substituents at C-1 and C-5. |
3. | A furanose site as in calyptrate flies does not exist inDrosophila. First, D-galactose, phenylalanine and 2,5-anhydro-D-mannitol are not or nearly not stimulatory. Secondly, according to different sugar receptor responses after treatment of the taste hairs with papain, D-fucose binds to another receptor site than D-fructose. Thirdly, the effective conformation of D-fructose is not the furanose, but most probably the pyranose form as can be concluded from experiments with freshly prepared and equilibrium solutions of D-fructose. |
4. | The characteristic differences between the properties of the sugar receptors ofDrosophila and of the calyptrate flies lead to the suggestion that the actual number of types of receptor sites in the various fly species is greater than assumed up till now. The broad specificity of the sugar receptors of flies may therefore result from a mosaic of different types of highly specific receptor sites. |
9.
Maciej Poltorak Mark A. Frye Renee Wright †John J. Hemperly Mark S. George Peggy J. Pazzaglia Shari A. Jerrels Robert M. Post William J. Freed 《Journal of neurochemistry》1996,66(4):1532-1538
Abstract: Neural cell adhesion molecule (N-CAM) is involved in cell-cell interactions during synaptogenesis, morphogenesis, and plasticity of the nervous system. Disturbances in synaptic restructuring and neural plasticity may be related to the pathogenesis of several neuropsychiatric diseases, including mood disorders and schizophrenia. Disturbances in brain cellular function may alter concentrations of N-CAM in the CSF. Soluble human N-CAM proteins are detectable in the CSF but are minor constituents of serum. We have recently found an increase in N-CAM content in the CSF of patients with schizophrenia. Although the pathogenesis of both schizophrenia and mood disorders is unknown, ventriculomegaly, decreased temporal lobe volume, and subcortical structural abnormalities have been reported for both disorders. We have therefore measured N-CAM concentrations in the CSF of patients with mood disorder. There were significant increases in amounts of N-CAM immunoreactive proteins, primarily the 120-kDa band, in the CSF of psychiatric inpatients with bipolar mood disorder type I and recurrent unipolar major depression. There were no differences in bipolar mood disorder type II patients as compared with normals. There were no significant effects of medication treatment on N-CAM concentrations. It is possible that the 120-kDa N-CAM band present in the CSF is derived from CNS cells as a secreted soluble N-CAM isoform. Our results suggest the possibility of latent state-related disturbances in N-CAM cellular function, i.e., residue from a previous episode, or abnormal N-CAM turnover in the CNS of patients with mood disorder. 相似文献
10.
The effect of season on "biofilming";, as a cue for the settlement of marine invertebrate larvae, was investigated in a long-term field study during the years 1992-1994. The series of settlement experiments was conducted in a tidal rapid on the west coast of Scotland, and involved manipulations of artificial panels. Biofilming of substrata, whilst excluding larval settlement, was achieved by the enclosure of panels within tight-fitting (but removable) mesh screens so that the number of settlers on filmed and unfilmed substrata were counted in the initial absence of other incumbent post-larvae. Depending on larval species, the effects of biofilming were found to be either facilitatory or inhibitory. Significant within- and between-species seasonal differences in the settlement responses were detected, and a reversal of the effect of biofilming on larval settlement response, from inhibitory to facilitatory and vice versa, was noted with season in the case of some taxonomic groups and species (e.g. Tubulipora sp., Plagioecia sp., Electra pilosa (L.)). The present study emphasizes the need for extended field studies of larval responses to environmental cues, when the focus of interest is in drawing general inferences about naturally occurring behavioural patterns at settlement. 相似文献