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11.
FRANCOIS MOUGEOT MARK MOSELEY FIONA LECKIE JESUS MARTINEZ-PADILLA ALLEN MILLER MAT POUNDS R. JUSTIN IRVINE 《The Journal of wildlife management》2008,72(2):468-472
ABSTRACT Ticks are important arthropod vectors of diseases of human, livestock, and wildlife hosts. In the United Kingdom, the sheep tick (Ixodes ricinus) is increasingly recognized as a main limiting factor of red grouse (Lagopus lagopus) populations, a game bird of high economic value. We evaluated the effectiveness of a new practical technique that could help managers reduce negative impacts of ticks on young grouse. In a replicated field experiment, we treated breeding females with leg bands impregnated with permethrin, a slow-releasing potent acaracide. We found that treatment reduced tick burdens on young chicks. Because this treatment is easily applied, it offers a new practical management tool to tackle problems caused by ticks in game bird populations. 相似文献
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ROSA M. RIOS JESUS MARTIN ANTONIO TORRES CONCEPCION FEDRIANI 《The Journal of eukaryotic microbiology》1992,39(5):584-588
ABSTRACT Three polyclonal antibodies raised against Paraurostyla sp. cyst wall polypeptides of molecular weight 110,000 (p110), 66,000 (p66) and 52,000 (p52) have been obtained. The specificity of the antisera was tested by immunoblotting. Anti-p110 antibody detected five bands of 300, 170, 135, 110 and 40 kDa, respectively. Antiserum obtained against p66 recognized only this protein. Anti-p52 antiserum showed reaction for two different bands of 52 and 44 kDa, respectively. The precise localization of these proteins in the cyst wall was assessed by light microscope immunocytochemistry. Anti-p110 antiserum produced a strong positive reaction in both the ectocyst and endocyst. Both anti-p66 and anti-p52 antibodies recognized the ectocyst. 相似文献
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PURIFICACION CALVO JESUS MARTIN PILAR DELGADO ANTONIO TORRES 《The Journal of eukaryotic microbiology》1988,35(2):177-181
ABSTRACT Cortical morphogenesis during excystment in Histriculus similis has been studied by light microscopy of preparations impregnated with silver proteinate (protargol). This morphogenesis shows clear differences from cortical morphogenesis during division. The oral, paroral, and fronto-ventro-transverse primordia originate from an extensive field of kinetosomes. The marginal cirral primordia and the dorsal bristle primordia appear at an early stage of morphogenesis. The left marginal cirral primordium originates from the oral primordium. 相似文献
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1. We studied stress responses and metal exchange (uptake and loss) kinetics in the aquatic moss Fontinalis antipyretica Hedw. following transplant (in plastic mesh bags) to clean and metal-contaminated river sites and under laboratory conditions. 2. The stress response (estimated on the basis of chlorophyll:phaeophytin ratio) was more pronounced, and the moss took longer to recover, following transplant to heavily contaminated sites. 3. Metal uptake over the 28 day exposure period was predicted well by a two-compartment kinetic model: uptake velocity was initially high and gradually declined, with metal concentration in the moss showing a tendency to reach an equilibrium with metal concentration in the water. Mean uptake rate, time to reach equilibrium and metal concentration in moss at equilibrium all increased with increasing metal concentration in the water. 4. Bioconcentration constants calculated on the basis of our data rank the metals studied in the order Zn < Ni < Co < Cu < Pb < Cd. 5. Following retransplant of mosses to a clean site, metal loss was not predicted well by a passive exchange mode of the above type; instead, two phases (rapid and slow) were apparent. Loss rates during both phases, and proportion of metal load lost during the rapid phase, were proportional to the concentration of metal in the moss at the start of the recuperation trial. 6. We present nomograms to allow estimation of severity of contamination on the basis of metal concentration in moss and duration of transplant. 相似文献
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JESUS M. AVILES ANDERS P. MØLLER 《Biological journal of the Linnean Society. Linnean Society of London》2003,79(4):543-549
Host populations tend to show less ability to discriminate against parasites when living in their absence. However, comparison of rejection rates among sympatric and allopatric host populations does not allow determination of whether the greater tolerance in allopatric populations reflects a genetic change or phenotypic plasticity. Here we test the existence of changes in a host's adaptation to brood parasitism in the absence of parasitism by studying intraclutch variation in egg appearance, which is a genetically determined component of host defence favouring discrimination of parasitic eggs. We investigated egg phenotypes of a common host of the European cuckoo, Cuculus canorus , in the presence and in the absence of cuckoos. By using objective spectroradiometry techniques of colour assessment we compared intraclutch variation between populations of meadow pipit, Anthus pratensis , sympatric (England) and allopatric (Iceland and Faeroe Islands) with C. canorus . Allopatric populations of A. pratensis showed greater intraclutch variation in egg appearance in the ultraviolet part of the spectrum than did a population sympatric with C. canorus . Two possible alternative mechanisms explaining these findings are discussed. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 543–549. 相似文献
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JUAN J. SOLER JESUS M. AVILES MANUEL SOLER ANDERS P. MØLLER 《Biological journal of the Linnean Society. Linnean Society of London》2003,79(4):551-563
Brood parasitism in birds is one of the best examples of coevolutionary interactions in vertebrates. Coevolution between hosts and parasites is assumed to occur because the parasite imposes strong selection pressures on its hosts, reducing their fitness and thereby favouring counter-adaptations (e.g. egg rejection) which, in turn, select for parasite resistance (e.g. egg mimicry). Great spotted cuckoos ( Clamator glandarius ) are usually considered a brood parasite with eggs almost perfectly mimicking those of their host, the magpie ( Pica pica ). However, Cl. glandarius also exploits South African hosts with very different eggs, both in colour and size, while the Cl. glandarius eggs are similar to those laid in nests of European hosts. Here, we used spectrophotometric techniques for the first time to quantify mimicry of parasitic eggs for eight different host species. We found: (1) non-significant differences in appearance of Cl. glandarius eggs laid in nests of different host species, although eggs laid in South Africa and Europe differed significantly; (2) contrary to the general assumption that Cl. glandarius eggs better mimic those of the main host in Europe ( P. pica ), Cl. glandarius eggs more closely resembled those of the azure-winged magpie ( Cyanopica cyana ), a potential host in which there is no evidence of recent parasitism; (3) the appearance of Cl. glandarius eggs was not significantly related to the appearance of host eggs. We discuss three possible reasons why Cl. glandarius eggs resemble eggs of some of their hosts. We suggest that colouration of Cl. glandarius eggs is an apomorphic trait, and that variation between eggs laid in South African and European host nests is due to genetic isolation among these populations and not due to variation in colouration of host eggs. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 551–563. 相似文献
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Lessons learned in developing community mental health care
in Latin American and Caribbean countries
DENISE RAZZOUK GUILHERME GREG��RIO RENATO ANTUNES JAIR DE JESUS MARI 《World psychiatry》2012,11(3):191-195
This paper summarizes the findings for the Latin American and Caribbean
countries of the WPA Task Force on Steps, Obstacles and Mistakes to Avoid
in the Implementation of Community Mental Health Care. It presents an overview
of the provision of mental health services in the region; describes key experiences
in Argentina, Belize, Brazil, Chile, Cuba, Jamaica and Mexico; and discusses
the lessons learned in developing community mental health care. 相似文献
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