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Long-term assessments of species assemblages are valuable tools for detecting species ecological preferences and their dispersal
tracks, as well as for assessing the possible effects of alien species on native communities. Here we report a 50-year-long
study on population dynamics of the four species of land flatworms (Platyhelminthes, Tricladida, Terricola) that have colonized
or become extinct in a 70-year-old Atlantic Forest regrowth remnant through the period 1955–2006. On the one hand, the two
initially most abundant species, which are native to the study site, Notogynaphallia
ernesti and Geoplana multicolor have declined over decades and at present do not exist in the forest remnant. The extinction of these species is most likely
related with their preference for open vegetation areas, which presently do not exist in the forest remnant. On the other
hand, the neotropical Geoplaninae 1 and the exotic Endeavouria septemlineata were detected in the forest only very recently. The long-term study allowed us to conclude that Geoplaninae 1 was introduced
into the study area, although it is only known from the study site. Endeavouria septemlineata, an active predator of the exotic giant African snail, is originally known from Hawaii. This land flatworm species was observed
repeatedly in Brazilian anthropogenic areas, and this is the first report of the species in relatively well preserved native
forest, which may be evidence of an ongoing adaptive process. Monitoring of its geographic spread and its ecological role
would be a good practice for preventing potential damaging effects, since it also feeds on native mollusk fauna, as we observed
in lab conditions.
Júlio Pedroni: Granted by CNPQ–Brazil. 相似文献
14.
Monoclonal antibodies were produced to electrophoretically pure hydrogenase fromThiocapsa roseopersicina. Protein immunoelectroblotting was used to identify the hydrogenase-specific antibodies. Among the 18 monoclonal antibodies selected by enzyme immunoassay, three were found to react with highly immunogenic trace contaminating proteins. One cell line produced antibody that inhibitied hydrogenase activity. This was the first specific inhibitor of the hydrogenase function. The results suggest that monoclonal antibodies could provide valuable new informations about the enzyme structure as well. 相似文献
15.
J Ignacio Andrés Jesús Alcázar José M Alonso Adolfo Díaz Javier Fernández Pilar Gil Laura Iturrino Encarna Matesanz Theo F Meert Anton Megens Victor K Sipido 《Bioorganic & medicinal chemistry letters》2002,12(2):249-253
Following the programme started at Janssen Research Foundation searching for 5-HT(2A/2C) antagonists, we now report on the synthesis of a series of substituted 2-(Dimethylaminomethyl)-2,3,3a,8-tetrahydrodibenzo[c,f]isoxazolo[2,3-a]azepine derivatives. The 5-HT(2A), 5-HT(2C) and H(1) receptor affinities as well as the mCPP antagonistic activity of the compounds synthesised is described. 相似文献
16.
17.
A Eyquem L No?l C Bosser G Brochier 《Revue fran?aise de transfusion et immuno-hématologie》1984,27(4):487-491
A major haemophiliac A, 27 years old, has been treated during 30 months, with high dosage of imported Factor VIII, in order to reduce the titer of a F VIII antibody. A good clinical result has been obtained. No sign of immunodeficiency has been observed. Normal values were obtained for T4/T8, ratio B2 microglobulin and no antibody was detected against the LAV virus isolated from cases of AIDS. 相似文献
18.
An abnormal terminal X-Y interchange accounts for most but not all cases of human XX maleness 总被引:14,自引:0,他引:14
To determine if human XX maleness results from an abnormal chromosomal X-Y interchange, we studied the inheritance of the paternal pseudoautosomal region in nine patients. Those six patients in whom Y-specific DNA was found (Y(+)) inherited the entire pseudoautosomal region from the paternal Y chromosome and lost that of the paternal X chromosome. Moreover, in three Y(+) cases, we observed the deletion of a paternal Xp locus tightly linked to the pseudoautosomal region. These results definitively show that an abnormal and terminal X-Y interchange during paternal meiosis causes Y(+)XX maleness. In contrast, no abnormal X-Y interchange was observed in any of the three Y(-) cases analyzed, suggesting that maleness can occur in the absence of any Y-specific DNA. 相似文献
19.
Cystic fibrosis typing with DNA probes and screening for ΔF508 deletion in families from Southern France 总被引:1,自引:1,他引:0
Mireille Claustres Marie Desgeorges Paule Kjellherg Hélène Bellet Jacques Demaille Michelle Ramsay 《Human genetics》1990,85(4):398-399
Summary A sample of 235 individuals from 49 French cystic fibrosis (CF) families with at least one living affected child was typed
with probes for restriction fragment length polymorphisms (RFLPs) known to be linked to the CF gene, and was screened for
the ΔF508 mutation. Using a combination of six probes, 44 out of the 49 families were sufficiently informative to enable prenatal
diagnosis or carrier determination. As in many other populations, linkage disequilibrium was found between the CF locus and
the haplotype B (XV2c: allele 1; KM19: allele 2), which accounts for about 78% of CF chromosomes in our families. The ΔF508
deletion was present in 64.3% of CF chromosomes. 相似文献
20.
Marie-Hélène Chaput Darasinh Sihachakr Georges Ducreux Dominique Marie Nasrine Barghi 《Plant cell reports》1990,9(8):411-414
In order to regenerate somatic hybrids, mesophyll protoplasts from a dihaploid potato, BF15 (H1), were electrofused with those from two other dihaploid clones, Aminca (H6) and Cardinal (H3). Determination of the ploidy level by flow cytometry showed that 10% of plants regenerated from the fusion experiment with BF15 + Aminca were diploids, 14% triploids, 63% tetraploids and very few were mixoploids or had a higher ploidy level. Using morphological markers and vigour in plant growth, we were able to recover a total of 24 somatic hybrid plants, respectively 20 and 4 hybrids (accounting for 12% and 13% of regenerants) from the fusions BF15 + Aminca and BF15 + Cardinal. Most of the somatic hybrids were at the expected tetraploid level (2n=4x=48). The hybrid nature was confirmed by examining isoenzyme patterns for malate dehydrogenase (MDH) and isocitrate dehydrogenase (ICD). 相似文献