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921.
The kestrel (Falco tinnunculus L.) in Berlin: investigation of breeding biology and feeding ecology 总被引:1,自引:0,他引:1
Approximately 200–250 pairs of kestrels (Falco tinnunculus) breed in Berlin, preferentially in nest boxes. From 2002 to 2004, ten monitoring sites (breeding sites) characterised by different housing structure, land utilisation, vegetation cover and degree of building density were studied in Berlin: four in the city centre, three in a mixed zone and three in the outskirts. All pairs bred in nest boxes, so the reproductive success could easily be determined. Pellets, and feathers of bird prey species, were collected during the breeding seasons, and the food spectrum was determined based on these remains. There was no significant difference in the reproductive success of the kestrels between the three zones. Data on the number of fledged young indicated a sufficient food supply. In total, 9 species of mice and shrews, 23 bird species and 31 beetle species were identified as prey of kestrels. Urban kestrels specialise in hunting birds if mice and shrews are not readily available, with the house sparrow (Passer domesticus) as the favoured prey bird. Of note are anthropogenic food items, such as cutlet bones, that were found only in the city centre. This shows that the kestrel can adapt itself to humans with regard to its diet. There was no urban gradient with regard to reproductive success, but there was with the composition of food, such as the domination of bird prey in the city centre. The number of individual items of bird prey decreased from the centre to the outskirts. In conclusion, the results show that the kestrel is an opportunistic species which survives well anywhere in the city of Berlin.
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Stefan KupkoEmail: |
922.
Gabrijel M Repnik U Kreft M Grilc S Jeras M Zorec R 《Biochemical and biophysical research communications》2004,314(3):717-723
The fusion of antigen presenting and cancer cells leads to the formation of hybrid cells, which are considered a potential vaccine for treating cancer. The quality assessment of hybrid cell vaccines is crucial for the introduction of this new treatment. Flow cytometry was the method used recently, since it is faster in comparison to classical microscopy. Here we describe a rapid confocal microscopy based approach to quantify hybrid cell yields. The extent of fusion rate was determined by confocal microscopy by counting dual fluorescent cells and by measuring the area of co-localized pixels. Results of both methods showed high degree of correlation. The same samples were also analyzed by flow cytometry. Fusion rates determined with both techniques showed significant correlation. In conclusion, using confocal microscopy we developed a sensitive and a rapid method to assess the yield of hybridomas in a large number of electrofused cells. 相似文献
923.
Prohaska SJ Fried C Amemiya CT Ruddle FH Wagner GP Stadler PF 《Journal of molecular evolution》2004,58(2):212-217
The statistical analysis of phylogenetic footprints in the two known horn shark Hox clusters and the four mammalian clusters shows that the shark HoxN cluster is HoxD-like. This finding implies that the most recent common ancestor of jawed vertebrates had at least four Hox clusters, including those which are orthologous to the four mammalian Hox clusters. 相似文献
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925.
Garnatje T Vallès J Garcia S Hidalgo O Sanz M Canela MA Siljak-Yakovlev S 《Biology of the cell / under the auspices of the European Cell Biology Organization》2004,96(2):117-124
Genome size was assessed by flow cytometry in 33 species belonging to seven genera of the tribe Cardueae (Asteraceae), which can be grouped in three taxonomic complexes. 2C nuclear DNA content ranged from 1.49 to 16.98 pg, which is more than elevenfold variation. Genome size correlated well with some karyological traits. Nuclear DNA amount variations also have systematic and evolutionary implications and/or are linked to adaptations to ecological conditions. 相似文献
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928.
Doerre S Mesires KP Daley KM McCarty T Knoetig S Corley RB 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(2):983-991
The levels and stability of IkappaBepsilon have been examined in unstimulated and stimulated splenic B cells and compared with that of IkappaBalpha and IkappaBbeta. Primary murine splenic B cells but not T cells were found to contain high levels of IkappaBepsilon protein, equivalent to levels of the abundant IkappaBalpha. Most agents that activate IkappaBalpha and IkappaBbeta degradation do not induce rapid degradation of IkappaBepsilon. Interestingly, however, the levels of IkappaBepsilon, but not of IkappaBalpha or IkappaBbeta, are dramatically reduced upon the stimulation of B cells both in vivo and in vitro. Since IkappaBepsilon exhibits substrate specificity for NF-kappaB Rel homodimers, this suggested the possibility that changes in NF-kappaB-responsive genes might also occur during this transition. Consistent with this hypothesis, we found that a NF-kappaB reporter construct sensitive to p65/RelA homodimers is activated at the time that IkappaBepsilon levels decline following B cell stimulation. In IgG(+) B cell lines, which contain low levels of IkappaBepsilon, this same reporter construct was inactive, suggesting that the increases in Rel homodimer activity that accompany B cell stimulation are transient. However, there are differences in the level of expression of NF-kappaB-responsive genes in these IgG(+) B cell lines compared with their IgM(+) counterparts. From these data, we conclude that there are transient changes in NF-kappaB activity due to reductions in IkappaBepsilon, which might contribute to long-term, persistent changes that accompany B cell differentiation. We propose an important role for IkappaBepsilon in the differential regulation of nuclear NF-kappaB activity in stimulated B cells. 相似文献
929.
CCL18 is expressed in atopic dermatitis and mediates skin homing of human memory T cells 总被引:7,自引:0,他引:7
Günther C Bello-Fernandez C Kopp T Kund J Carballido-Perrig N Hinteregger S Fassl S Schwärzler C Lametschwandtner G Stingl G Biedermann T Carballido JM 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(3):1723-1728
CCL18 is a human chemokine secreted by monocytes and dendritic cells. The receptor for CCL18 is not yet known and the functions of this chemokine on immune cells are not fully elucidated. In this study, we describe that CCL18 is present in skin biopsies of atopic dermatitis (AD) patients but not in normal or psoriatic skin. CCL18 was specifically expressed by APCs in the dermis and by Langerhans and inflammatory dendritic epidermal cells in the epidermis. In addition, the serum levels of CCL18 and the percentages of CCL18-producing monocyte/macrophages and dendritic cells were significantly increased in AD patients compared with healthy controls. Furthermore, we demonstrate that CCL18 binds to CLA(+) T cells in peripheral blood of AD patients and healthy individuals and induces migration of AD-derived memory T cells in vitro and in human skin-transplanted SCID mice. These findings highlight a unique role of CCL18 in AD and reveal a novel function of this chemokine mediating skin homing of a subpopulation of human memory T cells. 相似文献
930.
Kim S. Grützmacher Verena Keil Sonja Metzger Livia Wittiger Ilka Herbinger Sebastien Calvignac-Spencer Kerstin Mätz-Rensing Olivia Haggis Laurent Savary Sophie Köndgen Fabian H. Leendertz 《EcoHealth》2018,15(2):462-466
Despite being important conservation tools, tourism and research may cause transmission of pathogens to wild great apes. Investigating respiratory disease outbreaks in wild bonobos, we identified human respiratory syncytial virus and Streptococcus pneumoniae as causative agents. A One Health approach to disease control should become part of great ape programs. 相似文献