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TOSHIHIRO TOKIWA DAVID MODRÝ AKIRA ITO KATEŘINA POMAJBÍKOVÁ KLÁRA J. PETRŽELKOVÁ SOICHI IMAI 《The Journal of eukaryotic microbiology》2010,57(2):115-120
ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids. 相似文献
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M Chiron J M Darbon F Roubinet G Cassar J P Jaffrezou C Bordier G Laurent 《Cellular immunology》1990,130(2):339-351
Modulation of CD5 expression by TPA was investigated on T-leukemic cell lines corresponding to different stages of ontogeny. These CD5 changes have been analyzed simultaneously with modifications of cell growth, cell cycle, cell surface phenotype, and PKC content. CD5 expression was found 6- to 17-fold increased by TPA in a dose-dependent manner on phenotypically mature T-cells (Jurkat, JM, and T-CLL) while T-cells from earlier stages of differentiation (CEM III, CEM 95, and CEM 44) were found unresponsive. CD5 upregulation on TPA-sensitive JM cells appears correlated with inhibition of cell growth, blockage in G1 phase, and phenotypic maturation (downregulation of CD7 and CD1 antigens) and seemed to be related to PKC activation since DiC8 (a PKC activator) mimicked this TPA effect and H7 (a PKC inhibitor) partially reduced it. On the other hand, on CEM III cells TPA induced no modulation of CD5 antigen, a less dramatic effect on cell growth and cell cycle, but a CD7 downregulation. TPA appeared fully effective in binding and translocating PKC in both CEM III and JM cells, although the PKC activity level was three times higher in the latter. Finally, our study suggests that CD5 expression is at least partially under control of PKC in phenotypically mature neoplastic T-cells while PKC could not be directly involved in the regulation of CD5 antigen in leukemic cells arrested at earlier stages of differentiation. 相似文献
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The worldwide increase in the use of antibiotics as an integral part of poultry and livestock production industry has recently received increasing attention as a contributory factor in the international emergence of antibiotic-resistant bacteria in human beings. To gauge the presence of the aforementioned scenario in the Indian context, a preliminary survey was conducted to assess the use of chlortetracycline (CTC) in 12 commercial layer farms and to quantify and confirm its residue in the egg. Samples of feed and eggs were collected at day 0 (prior to CTC addition), 3rd, 5th and 7th day during treatment and on the 9th and 14th day (2nd and 7th day after withdrawal of CTC) from each of the 12 commercial poultry farms studied. Concentration of CTC in feed was significantly (P<0.01) high on the 3rd, 5th and 7th day. On the 9th day and 14th day CTC concentration in feed was significantly (P<0.01) lower compared to the earlier 3 days studied. A highly significant difference (P<0.01) of the antibiotic residue in egg was observed in all the 5 days with high residual levels of CTC in egg. CTC in feed and its residue in egg were detected even on the 9th and 14th day respectively. 相似文献
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KLARA BJÖRG JAKOBSDÓTTIR þÓRA DÖGG JÖRUNDSDÓTTIR SIGURLAUG SKÍRNISDÓTTIR SIGRÍÐUR HJÖRLEIFSDÓTTIR GUÐMUNDUR Ó. HREGGVIÐSSON ANNA KRISTÍN DANÍELSDÓTTIR CHRISTOPHE PAMPOULIE 《Molecular ecology resources》2006,6(2):337-339
Nine out of 22 microsatellite primers tested were successfully amplified on three samples of cod Gadus morhua L. (two contemporary and one archived otolith samples). All loci were polymorphic (5–23 alleles/locus). The average observed heterozygosity across loci and samples was 0.625, ranging from 0.294 to 0.895 at each locus. All loci were under Hardy–Weinberg equilibrium, except PGmo56 that showed significant excess of heterozygotes in all studied samples. The isolated loci were suitable for degraded DNA and therefore useful for conducting a long‐term temporal study with DNA obtained from archived otoliths of cod. 相似文献
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Abstract 1. Body size in parasitic insects can be subjected to contrasting selective pressures, especially if they complete their development within a single host. On the one hand, a larger body size is associated with a higher fitness. On the other hand, the host offers a discrete amount of resources, thus constraining the evolution of a disproportionate body size. 2. The present study used the weevil Curculio elephas as a study model. Larvae develop within a single acorn, feeding on its cotyledons, and larval body size is strongly related to individual fitness. 3. The relationship between larval and acorn size was negatively exponential. Larval growth was constrained in small acorns, which did not provide enough food for the weevils to attain their potential size. Larval size increased and levelled off in acorns over a certain size (inflexion point), in which cotyledons were rarely depleted. When there were more than one larva per acorn, a larger acorn was necessary to avoid food depletion. 4. The results show that C. elephas larvae are sometimes endoparasitic, living on the edge of host holding capacity. If they were smaller they could avoid food depletion more easily, but the fitness benefits linked to a larger size have probably promoted body size increase. The strong negative effects of conspecific competition may have possibly influenced female strategy of laying a single egg per seed. 5. Being larger and fitter, but always within the limits of the available host sizes, may be one main evolutionary dilemma in endoparasites. 相似文献