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1.
2.
Delayed type hypersensitivity against antigens of Fasciola hepatica has been repeatedly documented in infected hosts. Evidence has been presented to suggest that the delayed reactivity may develop earlier in the regional lymph nodes of the parasitized organ than in other lymph nodes of the body (Soulsby 1971). 相似文献
3.
C. H. Eriksen 《Hydrobiologia》1964,23(3-4):506-510
Summary
Ephemera simulans maintains an oxygen consumption in a suitable substratum (Ø-1) of approximately 0.23 cc/g/hr from at least February, and probably before, through approximately the middle of April at which time it rises to around 0.37 cc/g/hr (Table I). Such data indicate quite clearly that a rise in metabolic rate occurs in the spring in this burrowing mayfly. A surge of growth and gonad development in April and May is here suggested as the factor most likely responsible for the metabolic increase. Observation of successive collections of nymphs at this time of year makes obvious the rapid development.
Zusammenfassung Ephemera simulans hält in einem geeigneten Substratum (Ø-1) von ungefähr 0.23 cc/g/hr einen Sauerstoff-Verbrauch aufrecht, der von mindestens Februar an, und wahrscheinlich bevor, bis etwa Mitte April dauert, und zu welcher Zeit die Ablesung auf etwa 0.37 cc/g/hr ansteigt. Diese Daten zeigen ganz offensichtlich, dass ein Ansteigen der metabolischen Geschwindigkeit im Frühling, in dieser sich eingrabenden Eintagsfliege, stattfindet. Ein Anschwellen des Wachstums und der Gonaden-Entwicklung im April und im Mai wird hier als ein Faktor vermutet, der sehr wahrscheinlich verantwortlich für das Ansteigen des Metabolismus ist. Die Beobachtung von aufeinanderfolgenden Sammlungen von Nymphen zu dieser Jahreszeit lässt die rasche Entwicklung offenbar werden.相似文献
4.
Summary Plasminogen activator inhibitor type-1 (PAI-1) was identified in extracts of rat adrenal medulla, and its immunohistochemical localization was studied together with that of tissue-type plasminogen activator (t-PA). By staining of adjacent sections and by doublestaining of the same section we demonstrate that the same cells of the adrenal medulla contain both PAI-1 and t-PA immunoreactivity in the cytoplasm. In addition a few ganglion cells of the adrenal medulla were found to contain PAI-1 but not t-PA. Neither of the components were found in the adrenal cortex. Analysis of extracts from isolated adrenal medulla using reverse zymography showed the presence of a plasminogen activator inhibitor with M
r46000. The inhibitory activity disappeared when the extract was passed through a column with sepharose-coupled anti-PAI-1 IgG, while the run-through from a similar column coupled with preimmune IgG still contained the inhibitor. The present findings suggest that PAI-1 could play a role in the regulation of t-PA activity in the rat adrenal gland medullary cells. 相似文献
5.
Eriksen Karin Landsverk Thor Gondrosen Bjørn Vormeland Jorunn 《Acta veterinaria Scandinavica》1990,31(4):445-451
Antisera against a number of Campylobacter species were used in immuno-histochemical and -cytochemical studies on cases of porcine intestinal adenomatosis. Avidin-biotin-complex (ABC) and streptavidin immunoperoxidase methods were used on formalin-fixed, paraffin-embedded and frozen sections. Protein A gold method was used on formaldehyde fixed and frozen sections for immuno-cytochemistry. The antisera used were raised in rabbits by subcutaneous or intravenous injection of living or formalin treated organisms. Antisera against different serotypes of the thermotolerant, catalase positive Campylobacters, Campylobacter jejuni and Campylobacter coli gave positive reactions in the immuno-histochemical studies. The staining was found in intestinal epithelial cells both in the ileum and in the colon and was restricted to the apical cytoplasm of adenomatous epithelial cells. The staining had a granular pattern, the positive structures sometimes having the shape of Campylobacter. Epithelial cells in areas with normal differentiation of goblet cells did not stain. In contrast, no staining resulted with antisera against Campylobacter sputorum subsp. mucosalis and Campylobacter hyointestinalis. Immuno-cytochemistry, using antisera against Campylobacter jejuni showed that the positive staining in altered epithelial cells were restricted to intracellular organisms having a structure resembling Campylobacter spp. 相似文献
6.
7.
Summary The solubility of oxygen in the liquid phase of a bioreactor was changed by a ramp change of temperature, and kLa was determined from the resulting return to equilibrium of dissolved oxygen activity. The maximum kLa that can be measured by this method in a standard laboratory scale bioreactor is 145 h–1 corresponding to a temperature change rate of 320°C h–1.Nomenclature p
Difference between pG and pL (% saturation)
- T
Ramp change of temperature (°C)
- E
Temperature-compensated output from the oxygen electrode (A)
- Eu
Uncompensated output from the oxygen electrode (A)
- kLa
Overall volumetric mass transfer coefficient (h–1)
- kLaTm
Overall volumetric mass transfer coefficient at temperature Tm (h–1)
- PG
Dissolved oxygen activity in equilibrium with the gas phase (% saturation)
- pL
Dissolved oxygen activity (% saturation)
- pLm
Dissolved oxygen activity at time tm (% saturation)
- t
Time (h)
- tm
Time of maximum p (h)
- T
Temperature (°C)
- Tcal
Calibration temperature of the oxygen electrode (°C)
- Tm
Final temperature after a temperature shift (°C)
- Tn
Temperature at time tn 相似文献
8.
9.
Identification and characterization of the murine cell surface receptor for the urokinase-type plasminogen activator. 总被引:5,自引:0,他引:5
H Solberg D L?ber J Eriksen M Ploug E R?nne N Behrendt K Dan? G H?yer-Hansen 《European journal of biochemistry》1992,205(2):451-458
Cell-binding experiments have indicated that murine cells on their surface have specific binding sites for mouse urokinase-type plasminogen activator (u-PA). In contrast to the human system, chemical cross-linking studies with an iodinated ligand did not yield any covalent adducts in the murine system, but in ligand-blotting analysis, two mouse u-PA-binding proteins could be visualized. To confirm that these proteins are the murine counterpart of the human u-PA receptor (u-PAR), a peptide was derived from the murine cDNA clone assigned to represent the murine u-PAR due to cross-hybridization and pronounced sequence similarity with human u-PAR cDNA [Kristensen, P., Eriksen, J., Blasi, F. & Dan?, K. (1991) J. Cell Biol. 115, 1763-1771]. A rabbit antiserum raised against this peptide specifically recognized two polypeptide bands with electrophoretic mobilities identical to those identified by ligand-blotting analysis. Binding of mouse u-PA to its receptor showed species specificity in ligand-blotting analysis, since mouse u-PA did not bind to human u-PAR and human u-PA did not bind to mouse u-PAR. The apparent M(r) of mouse u-PAR varied between different mouse cell lines and ranged over M(r) 45,000-60,000. In four of the cell lines, mouse u-PA bound to two mouse u-PAR variant proteins, whereas in the other two cell lines studied, there was only one mouse u-PA-binding protein. In the monocyte macrophage cell line P388D.1, trypsin-treatment of intact cells could remove only the large mouse u-PAR variant (M(r) 60,000) indicating that only this type was a cell-surface-exposed molecule. The smaller mouse u-PAR variant (M(r) 45,000), was deglycosylated by the enzyme endo-beta-N-acetylglucosaminidase H and is probably an intracellular precursor form carrying only high-mannose carbohydrate. Deglycosylation of this variant yielded a polypeptide with an apparent M(r) of about 30,000, which corresponds to the Mr calculated from the cDNA derived protein sequence of mouse u-PAR. Receptor-bound mouse u-PA could be released by phosphatidylinositol-specific phospholipase C treatment, indicating that mouse u-PAR is attached to the cell surface by glycosylphosphatidylinositol. Purification of the two mouse u-PAR variant proteins by diisopropylfluorophosphate-inactivated mouse u-PA-Sepharose affinity chromatography yielded two silver-stained bands when analysed by SDS/PAGE, corresponding in electrophoretic mobility to those seen by ligand-blotting analysis.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
10.
The cellular urokinase-type plasminogen-activator (uPA) receptor (uPAR) is a glycolipid-anchored membrane protein thought to be involved in pericellular proteolysis during cell migration and tumor invasion. In the present study, we have identified and characterized two soluble forms of uPAR which have retained their ligand-binding capability. One variant was generated in vitro by treatment of intact normal cells with either a phosphatidylinositol-specific phospholipase C (PLC) or endoproteinase Asp-N. The other soluble uPAR variant was secreted in vivo from peripheral blood leukocytes affected by the stem-cell disorder paroxysmal nocturnal hemoglobinuria (PNH), and was found in the plasma from these PNH patients as well as in the conditioned medium from cultured PNH leukocytes. Under normal conditions, we find no evidence for any shedding or secretion of a soluble uPA-binding counterpart to human uPAR in plasma. Unlike normal leukocytes, the PNH-affected cells do not express uPAR on the cell surface, although they do contain apparently normal levels of uPAR-specific mRNA. The secreted uPAR derived from PNH cells has a mobility in SDS/PAGE that is slightly higher than that of uPAR solubilized by PtdIns-specific PLC or detergent, but resembles that of a truncated, recombinant uPAR variant, which has its C-terminus close to the proposed glycolipid-attachment site, suggesting that the secreted protein has been proteolytically processed for glycolipid attachment. The presence in plasma from PNH patients of such a secreted, hydrophilic form of uPAR lends support to the hypothesis that the lesion underlying the PNH disorder resides either in glycolipid biosynthesis or in the function of an as-yet-unidentified transamidating enzyme assumed to cleave and assemble the truncated uPAR with the preformed glycolipid moiety. 相似文献