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381.
The results indicate that certain hemocyte proteins of the medfly, Ceratitis capitata, are responsible for the recognition of foreignness, since they are able to bind to the surface of Escherichia coli in vitro. Furthermore, when the E. Coli-hemocyte protein complex was incubated in the presence of tyrosine and phenoloxidase, the bacteria were immobilized, forming large aggregates. The formation of aggregates seems to be due to reactive tyrosine intermediate (quinone) generated by the action of phenoloxidase. © 1992 Wiley-Liss, Inc.  相似文献   
382.
Summary Since 1859, wintering Lesser White-fronted Geese have been recorded 25 times in Greece. Of the records obtained in the second half of the 19th century only two, based on museum specimens, are valid. There were four records in the first half of the present century, while all the others come from the second half due to increased coverage mostly during IWRB midwinter censuses. Their distribution had been more southerly in the past, but in recent years only northern Greek wetlands hold the bulk of the wintering population, with the Evros Delta being the most important area (12, or 48% of all records). The wintering population of the species in the Evros Delta is threatened by habitat destruction and shooting.
Zum Vorkommen der Zwerggans in Griechenland
Zusammenfassung Seit 1859 wurden in Griechenland 25mal Zwerggänse festgestellt; aus dem 19. Jh. liegen nur 2 sichere Nachweise vor. 4 Nachweise fallen in die erste Hälfte des 20. Jh., die restlichen alle in die zweite Hälfte, Die Verteilung der Funde scheint in der Vergangenheit weiter nach Süden gereicht zu haben; heute liegen nur aus dem Norden Beobachtungen vor. Der wichtigste Platz ist das Evros-Delta (12 von 25 Nachweisen; einmal 1630 Ind. im Februar 1963). Die Winterpopulation ist durch Biotopzerstörung und Abschuß bedroht.
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383.
The events occurring during the spontaneous mixing of an okra mucilage-based model liquid food with saliva were recorded, with a focus on the local dynamics of colloidal particles contained therein. An okra mucilage containing fluorescent microsphere probes (assuming the role of model emulsion droplets), was brought into contact with reconstituted saliva on the welled slide of a confocal microscope. The movement of the probes at the saliva–mucilage interface and in the bulk mucilage has been recorded over periods of 60 min. Data have been obtained on the total mobility of individual model droplets, their diffusion coefficients, and the local viscosities, providing information on the dynamics of processes which occur during the oral processing of colloidal liquids. The role of osmotic pressure gradients on the spreading of the droplets into saliva is discussed in relation to the microrheology data.  相似文献   
384.
T-cell colony-forming cells (T-CFC) from 13 of 17 patients with T-ALL generated colonies in methylcellulose in the absence of added growth factors or mitogenic stimulation. As previously described, these colonies were composed of immature T cells displaying the same karyotypic abnormalities as fresh leukemic cells. Biochemically purified (bIL-2) and recombinant IL-2 (rIL-2) without any mitogen enhanced colony growth from both unfractionated and blast-enriched cell fractions in patients with a relatively low (less than 50 colonies/5 X 10(4) cells) plating efficiency. However, dose-response experiments revealed that the optimal dose of rIL-2 needed to enhance colony growth varied from patient to patient. Anti-IL-2 (DMS1) and anti-IL-2 receptor (anti-Tac) moAbs inhibited both spontaneous and rIL-2-induced colony formation in a dose-dependent manner. Direct staining of fresh leukemic cells with anti-Tac revealed less than 10% positive cells in all but two patients. However, cell incubation in the absence of growth factors or mitogens for 2-48 hr resulted in an increase of Tac+ cells. These observations indicate that a subset of immature T-CFC from T-ALL patients display functional IL-2-receptors. In addition, our findings strongly suggest that the IL-2/IL-2-R system could be involved in the spontaneous proliferation of some immature T-CFC of T-ALL patients.  相似文献   
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