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41.
Walter K. F. Seelentag Ursula Günthert Parvin Saremaslani Eva Futo Madeleine Pfaltz Philipp U. Heitz Jürgen Roth 《Histochemistry and cell biology》1996,106(3):283-289
CD44 isoforms have been implicated in tumor progression and metastasis formation. This study presents a thorough immunohistochemical
analysis of CD44 standard and isoform expression in normal human skin appendages and epidermis applying monoclonal antibodies
against CD44s, CD44v3, -v4, -v5, -v6, and -v9. An improved immunohistochemical protocol with microwave-based antigen retrieval
in paraffin sections and heavy metal amplification of the diaminobenzidine reaction product provided enhanced resolution and
sensitivity as compared to studies on frozen sections. The hair follicle, the seborrheic and eccrine sweat glands were strongly
positive for all CD44 isoforms studied. In the latter, the clear cells but not the dark (intercalated) cells were positive.
The sudoriferous ducts adjacent to the glands were weakly positive for all CD44 isoforms and strongly positive near the skin
surface. In the apocrine glands, the basal cells showed only a moderate positivity. The myoepithelial cells expressed only
CD44s. In the epidermis, all CD44 isoforms were detectable, with strongest CD44 immunostaining in the lower third of the stratum
spinosum and weaker staining in the stratum basale and the upper two-thirds of the stratum granulosum. The stratum granulosum
and corneum were unreactive. Thus, a regional and cell type-specific CD44 expression was revealed.
Accepted: 10 May 1996 相似文献
42.
Michael Keßler Hens J.G. ten Hoopen Josef J. Heijnen Shintaro Furusaki 《Biotechnology Techniques》1997,11(7):507-510
Despite the same mean volumetric power input of 19 and 47 W/m 3 , the specific oxygen uptake rate (OUR S ) of strawberry ( Fragaria ananassa) cell suspensions was higher in bioreactors equipped with a Rushton Turbine (4.4 and 6.2 3 10 -5 mol O 2 /kg.s) than with an anchor stirrer (2.5 and 4.6 3 10 -5 mol O 2kg.s). The increase in OUR S was caused by stress-activated respiration and appeared to be correlated with the locally dissipated power input. OUR S was corrected for the increase in surface through aggregate break-up and reached a maximum of 6.0 3 10 -5 mol O 2kg.s when agitating with approximately 200 kW/m 3 locally dissipated power input. 相似文献
43.
Johannes E. Philipp 《Radiation and environmental biophysics》1984,23(4):295-297
Summary In the above mentioned article [1] the notion of a time-dependent Gibbs free energy has been introduced to explain the observed time-pattern of embryo growth in seeds. Furthermore, the notion of a non-random thermal communication has been inferred from an inspection of the shapes of germination time distributions. It can be shown, however, that the reasoning leading to the time-dependent thermodynamic potential is based on inappropriate interpretation of kinetic equations, and that the shape of the distributions of germination time might be a natural consequence of the initial distribution of embryo size in the seeds.Discussion about the Paper Seed Germination as a Thermobiological Problem by L. G. Labouriau Radiation and Environmental Biophysics 15:345–366 (1978) 相似文献
44.
Marianne Philipp 《Ecography》1978,1(1):46-53
The vegetation of a snow bed has been described by a pin-point method and a modified Raunkiær frequency analysis. The thawing of the snow has been followed and some soil properties have been investigated. It is concluded that the composition of the vegetation in the snow bed is influenced mainly by the duration of the growth period, but locally the density and the species composition are determined by the downward flow of the melt water. 相似文献
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Summary The major human erythrocyte membrane (MN-) sialoglycoprotein was purified from MM, MN, and NN cells using detergent gel and ion exchange chromatography. N-terminal analyses with dansyl-chloride revealed serine in preparations from MM and leucine in those from NN erythrocytes, whereas glycoprotein isolated from MN cells contained both the above amino acids. These data strongly suggest that the above residues may represent the structural difference between the M and N antigens. Evidence was also obtained that the Ss-glycoprotein, which is associated with N activity, exhibits the same N-terminal amino acid (leucine) as the MN glycoprotein from MN cells. 相似文献
49.
Dialysis Continuous Process for Ammonium-Lactate Fermentation of Whey: Mathematical Model and Computer Simulation 总被引:3,自引:3,他引:0 下载免费PDF全文
A mathematical model was developed to describe a dialysis process for the continuous fermentation of whey lactose to lactic acid, with neutralization to a constant pH by ammonia. In the process, whey of a relatively high concentration is fed into the fermentor circuit at a relatively low rate so that the residual concentration of lactose is low. The fermentor effluent contains ammonium lactate, bacterial cells, and residual whey solids and could be used as a nitrogen-enriched feedstuff for ruminant animals. Only water is fed into the dialysate circuit at a relatively high rate. The dialysate effluent contains purified ammonium lactate and could be converted to lactic acid and ammonium sulfate for industry. The fermentation was specifically modeled as a set of equations representing material balances and rate relationships in the two circuits. Dialysis continuous fermentations, in general, were modeled by combining these equations and by using dimensionless parameters. The generalized model was then solved for the steady state and used to simulate the specific fermentation on a digital computer. The results showed the effects of various material and operational and kinetic parameters on the process and predicted that it could be operated efficiently. 相似文献
50.
Interaction of invertase with polyelectrolytes 总被引:1,自引:0,他引:1
Dautzenberg H Kötz J Philipp B Rother G Schellenberger A Mansfeld J 《Biotechnology and bioengineering》1991,38(9):1012-1019
In connection with our work on polyelectrolyte complex formation with polyampholytes, the interaction between invertase and several linear polyelectorlytes has been investigated by means of turbidimetry, light scattering measurements, and determination of the enzyme activity. Polyelectrolyte complex formation of invertase was shown to occur with cationic polyelectrolytes only. The light-scattering data yield information on aggregation and desegregation processes in complex formation. As indicated by our results, only a part of the protein molecules is engaged in this Coulombic interaction, and this part shows a rather small enzyme activity only. Thus, a direct interaction between invertase and a cationic polyelectrolyte is no effective approach to enzyme binding, but a complete immobilization of invertase can be achieved via an "inclusion flocculation" with a symplex formed by interaction between an anionic and a cationic linear polyelectrolyte or via immobilization in symplex microcapsules. 相似文献