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11.
K Folkers T Kubiak H Stepien N Sakura 《Biochemical and biophysical research communications》1980,97(2):601-606
A new approach to the study of the molecular arrangements of proteins in membranes is described. Irradiation with visible light of native erythrocytes or washed erythrocyte membranes suspended in buffers containing a) riboflavin, fluorescein or fluorescein coupled to dextran and b) 3H-labelled tryptophan resulted in incorporation of radioactivity into the membrane proteins. Polyacrylamide gel electrophoresis of solubilized membranes followed by radioactivity measurements of the separated membrane proteins revealed that in native erythrocytes the protein components known to be located at the exterior cell surface, Band 3 and the major sialoglycoproteins became specifically labelled, whereas in washed lysed cells all of the major membrane proteins were labelled. 相似文献
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Murielle Reboul Bernard Frangoulis Anna Rocca Laurent Degos Marika Pla 《Immunogenetics》1991,34(3):196-200
As a basis for the characterization of mouse T cells involved in the recognition of xenogeneic HLA molecules, a panel of HLA-B27-reactive cytotoxic T-cell clones was generated upon stimulation by cells from HLA-B27-transgenic mice. The HLA-B27-induced T-cell response was found to comprise two categories of clones: some recognizing HLA-B27 independent of H-2 molecules expressed by the target cells (unrestricted clones), others recognizing HLA-B27 in an H-2 restricted manner. The unrestricted clones exhibited diverse specificities, as judged from their various cross-reactivities with other xenogeneic (HLA) or allogeneic (H-2) molecules. In addition, although most of the unrestricted clones were able to react with both mouse and human HLA-B27-transgenic mice. The HLA-B27 induced T-cell which reacted only with HLA-B27-positive mouse, and not human cells. These findings illustrate that both H-2-restricted and unrestricted T cells with diverse species contribute to HLA-B27-xenorecognition. 相似文献
15.
Isaksson Axel Philips Anna–Carin Göransson Eva Björkenfeldt Henrik 《Acta veterinaria Scandinavica》1987,28(3-4):455-457
The electrical conductivity (EC) of milk is mainly a function of the electrolyte concentration in the milk and therefore raised in mastitis. The present investigation was aimed at elaborating, if possible, a diagnostic model for screening purposes based on EC determinations and consistent with the diagnostic procedures and interpretations commonly used in laboratory milk diagnosis in the Nordic countries (Klastrup 1975). According to this diagnosis (here called reference diagnosis) cell numbers above 300,000/ml (cell count or the corresponding CMT-score) in foremilk quarter samples during the main part of the lactation period and significantly above the lowest value on within-udder comparison during late lactation are considered indicative of mastitis and bacteriological examinations are made when called for. 相似文献
16.
Anna Maria Tagliasacchi Laura Maria Costantina Forino Manuela Frediani Silvana Avanzi 《Protoplasma》1983,115(2-3):95-103
Summary The pattern of DNA and RNA puffs in pair VII of polytene chromosomes has been investigated in the suspensor ofPhaseolus coccineus during early embryo development. The pattern of3H-TdR and3H-U incorporation has been also detected. Collected data indicate that: 1. both heterochromatic regions, p11 and q(111+112), of chromosome pair VII, organize large DNA puffs; 2. DNA puffs of both regions are specific of different embryo differentiation steps; 3. a seasonal influence on the DNA puffing seems also to be present, as demonstrated by the comparison of the results collected in two different crops; 4. the incorporation experiment by3H-TdR evidences that not all DNA puffs show clustered labeling; 5. the RNA puffing of the two regions seems also to be specific of determined embryo stages. 相似文献
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In this report we investigate the inhibition of membrane conductivity, due to the murine polyomavirus infection in permissive cells in culture. We define experimental conditions to have reproducible results and demonstrate that the intensity of the effects on the cell membrane, depends upon the virus titer used in the infection. Finally, the virus dependent effects disappear if the infection is performed in the presence of a drug that inhibits polymavirus DNA replication. 相似文献
19.
We designed an Integrated Media Preparation System (IMPS) for continuous, on-line preparation of cell culture media and delivery to intermediate storage vessels or directly to a bioreactor. Key components of the IMPS include: a high precision, continuous fluid mixing device; formulation-specific liquid medium concentrates; validated process controls and membrane filtration; and automated dispensing into large volume flexible plastic containers. The IMPS system is designed to produce sterile, single-strength liquid medium from common raw materials at a delivery rate of 1000–3000 liters per hour and will manufacture homogenous batches from several thousand liters to over 60,000 liters. Fortified nutrient media prepared from multi-component 50X concentrates have been demonstrated to accelerate bioreactor seed chains, increase product yield, and reduce the overall manufacturing cost of nutrient medium. A productivity matrix will analyze the fully-loaded costs and contrast alternative methods for media preparation against projected biological yield.Abbreviations IMPS
Integrated Media Preparation System
- 50X
Nutrient fluid components formulated at fifty-fold final use concentration
- 1X
Nutrient fluid formulated at final, single-strength use concentration
- cGMP
Current Good Manufacturing Practices
- SCADA
Supervisory Control and Data Acquisition
- PLC
Process Logic Controller
- LTI
Life Technologies, Inc.
- WFI
Water for Injection
- CIP
Clean in place
- SIP
Sterilize in place
- HPLC
High performance liquid chromatography
- DMEM
Dulbecco's Modified Eagle's Medium 相似文献
20.
A new mutation inEscherichia coli K12,isfA, is described, which causes inhibition of SOS functions. The mutation, discovered in a ΔpolA + mutant, is responsible for inhibition of several phenomena related to the SOS response inpolA + strains: UV- and methyl methanesulfonate-induced mutagenesis, resumption of DNA replication in UV-irradiated cells, cell filamentation, prophage induction and increase in UV sensitivity. TheisfA mutation also significantly reduces UV-induced expression of β-galactosidase fromrecA::lacZ andumuC′::lacZ fusions. The results suggest that theisfA gene product may affect RecA* coprotease activity and may be involved in the regulation of the termination of the SOS response after completion of DNA repair. TheisfA mutation was localized at 85 min on theE. coli chromosome, and preliminary experiments suggest that it may be dominant to the wild-type allele. 相似文献