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1.
J Environ Manage ; 299: 113452, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34526276

RESUMO

Cadiz Bay is a shallow mesotidal lagoon with extensive populations of the seagrass Cymodocea nodosa at intertidal and shallow subtidal elevations. This work aims to understand the mechanisms behind the resilience of this species to gradual sea level rise by studying its acclimation capacity to depth along the shallow littoral, and therefore, to gradual variations in the light environment. To address this objective, these populations have been monitored seasonally over a 10 year period, representing the longest seasonal database available in the literature for this species. The monitoring included populations at 0.4, -0.08 and -0.5 m LAT. The results show that C. nodosa has a strong seasonality for demographic and shoot dynamic properties - with longer shoots and larger growth in summer (high temperature) than in winter (low temperature), but also some losses. Moreover, shoots have different leaf morphometry depending on depth, with small and dense shoots in the intertidal areas (0.4 m) and sparse large shoots in the subtidal ones (-0.08 and 0.5 m). These differences in morphometry and shoot dynamic properties, combined with the differences in shoot density, explain the lack of differences in meadow production balance (i.e. meadow growth - meadow losses) between the intertidal (0.4 m) and the deepest population (-0.5 m), supporting the long term resilience of Cymodocea nodosa in Cadiz Bay. This study contributes to the understanding of the mechanisms behind seagrass stability and resilience, which is particularly important towards predicting the effects of climate change on these key coastal ecosystems, and also highlights the value of continuous long-term monitoring efforts to evaluate seagrass trajectories.


Assuntos
Alismatales , Ecossistema , Aclimatação , Mudança Climática , Folhas de Planta
4.
Ecol Lett ; 17(1): 1-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24134461

RESUMO

Exotic plant invasions can notably alter the nitrogen (N) cycle of ecosystems. However, there is large variation in the magnitude and direction of their impact that remains unexplained. We present a structured meta-analysis of 100 papers, covering 113 invasive plant species with 345 cases of invasion across the globe and reporting impacts on N cycle-related metrics. We aim to explain heterogeneity of impacts by considering methodological aspects, properties of the invaded site and phylogenetic and functional characteristics of the invaders and the natives. Overall, plant invasions increased N pools and accelerated fluxes, even when excluding N-fixing invaders. The impact on N pools depended mainly on functional differences and was greater when the invasive plants and the natives differed in N-fixation ability, plant height and plant/leaf habit. Furthermore, the impact on N fluxes was related mainly to climate, being greater under warm and moist conditions. Our findings show that more functionally distant invaders occurring in mild climates are causing the strongest alterations to the N cycle.


Assuntos
Espécies Introduzidas , Ciclo do Nitrogênio , Plantas/metabolismo , Clima , Fixação de Nitrogênio , Filogenia , Plantas/genética
5.
Plant Biol (Stuttg) ; 11(6): 803-11, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19796357

RESUMO

Flowering phenology is an important and poorly understood plant trait that may possibly be related to the invasiveness potential of alien species. The present work evaluates whether flowering time of invasive alien species is a key trait to overcome the climatic filters operating in continental Mediterranean ecosystems of Spain (characterised by summer drought and low temperatures in winter). We conducted comparisons between the flowering phenology of the invasive species in their native range and in Spain, and between flowering phenology of 91 coexisting invasive-native species pairs. For the alien species, geographical change from the native to the invaded region did not result in shifts in the start and the length of the flowering period. Overall, climatic conditions in the native range of species selected for a flowering pattern is maintained after translocation of the species to another region. Flowering of tropical and temperate invasive alien species peaked in summer, which contrasts with the spring flowering of native and invasive alien species of Mediterranean climate origin. By exploiting this new temporal niche, these invasive alien species native to tropical and temperate regions benefit from reduced competition with natives for abiotic and biotic resources. We suggest that human-mediated actions have reduced the strength of the summer drought filter in particular microhabitats, permitting the invasion of many summer-flowering aliens.


Assuntos
Flores/crescimento & desenvolvimento , Ecossistema , Região do Mediterrâneo , Estações do Ano , Espanha , Especificidade da Espécie
6.
Rev. méd. Chile ; 135(3): 370-374, mar. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-456624

RESUMO

Gingival enlargement can be an adverse effect of ciclosporine A and nifedipine use. It has a high relapse rate if the drugs are not discontinued. There is a genetic predisposition to the development of this condition and dental biofilm can also play a role. We report a 64 years old male who received a renal allograft and was treated with cyclosporine and nifedipine. He required six surgical interventions for generalized gingival enlargement. After the sixth relapse, the patient was subjected to a periodontal treatment to eliminate the dental biofilm, which decreased the rate of recurrence of gingival enlargement.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Biofilmes/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Ciclosporina/efeitos adversos , Hiperplasia Gengival/induzido quimicamente , Imunossupressores/efeitos adversos , Nifedipino/efeitos adversos , Biofilmes/crescimento & desenvolvimento , Gengiva/ultraestrutura , Recidiva , Índice de Gravidade de Doença
9.
Clin Infect Dis ; 26(2): 308-13, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9502447

RESUMO

Epidemiological and clinical data are presented on 165 cases of Venezuelan hemorrhagic fever (VHF), a newly emerging viral zoonosis caused by Guanarito virus (of the family Arenaviridae). The disease is endemic in a relatively circumscribed area of central Venezuela. Since its first recognition in 1989, the incidence of VHF has peaked each year between November and January, during the period of major agricultural activity in the region of endemicity. The majority of cases have involved male agricultural workers. Principal symptoms among the patients with VHF included fever, malaise, headache, arthralgia, sore throat, vomiting, abdominal pain, diarrhea, convulsions, and a variety of hemorrhagic manifestations. The majority of patients also had leukopenia and thrombocytopenia. The overall fatality rate among the 165 cases was 33.3%, despite hospitalization and vigorous supportive care.


Assuntos
Febres Hemorrágicas Virais/epidemiologia , Febres Hemorrágicas Virais/fisiopatologia , Febres Hemorrágicas Virais/diagnóstico , Febres Hemorrágicas Virais/terapia , Humanos , Incidência , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estações do Ano , Venezuela/epidemiologia
10.
Lancet ; 338(8774): 1033-6, 1991 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-1681354

RESUMO

An outbreak of severe haemorrhagic illness began in the municipality of Guanarito, Portuguesa State, Venezuela, in September, 1989. Subsequent detailed study of 15 cases confirmed the presence of a new viral disease, designated Venezuelan haemorrhagic fever. Characteristic features are fever, toxicity, headache, arthralgia, diarrhoea, conjunctivitis, pharyngitis, leucopenia, thrombocytopenia, and haemorrhagic manifestations. Other features include facial oedema, cervical lymphadenopathy, nausea/vomiting, cough, chest or abdominal pain, and convulsions. The patients ranged in age from 6 to 54 years; all were residents of rural areas in central Venezuela, and 9 died. Infection with Guanarito virus, a newly recognised arenavirus, was shown by direct culture or by serological confirmation in all cases. Epidemiological studies suggest that the disease is endemic in some rural areas of central Venezuela and that it is rodent-borne. Venezuelan haemorrhagic fever has many similarities to Lassa fever and to the arenavirus haemorrhagic fevers that occur in Argentina and Bolivia.


Assuntos
Surtos de Doenças , Febre Hemorrágica Americana/epidemiologia , Doença Aguda , Adolescente , Adulto , Animais , Animais Selvagens/microbiologia , Arenavirus do Novo Mundo/isolamento & purificação , Criança , Feminino , Febre Hemorrágica Americana/complicações , Febre Hemorrágica Americana/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Roedores/microbiologia , Saúde da População Rural , Venezuela/epidemiologia
11.
Rev. argent. dermatol ; 67(3): 163-70, jul.-sept. 1986. Tab, ilus
Artigo em Espanhol | BINACIS | ID: bin-32248

RESUMO

Se presentan dos hermanos con porfiria eritropoyética congénita con manifestaciones clínicas y laboratoriales típicas de la enfermedad. El diagnóstico diferencial se implementó con la porfiria cutánea tardía infantil y la porfiria hepatoeritropoyética. En ambos pacientes se encontró masiva excreción de uro y coproporfirinas con predomino de la serie I. La actividad de la uro-D fue normal. El interés de la certificación del diagnóstico reside en la profilaxis que puede efectuarse para tratar de evitar las lesiones mutilantes características de la enfermedad (AU)


Assuntos
Pré-Escolar , Humanos , Masculino , Feminino , Eritropoese , Porfirias/congênito , Dermatopatias , Diagnóstico Diferencial , Porfirinas/análise
12.
Rev. argent. dermatol ; 67(3): 163-70, jul.-sept. 1986. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-34439

RESUMO

Se presentan dos hermanos con porfiria eritropoyética congénita con manifestaciones clínicas y laboratoriales típicas de la enfermedad. El diagnóstico diferencial se implementó con la porfiria cutánea tardía infantil y la porfiria hepatoeritropoyética. En ambos pacientes se encontró masiva excreción de uro y coproporfirinas con predomino de la serie I. La actividad de la uro-D fue normal. El interés de la certificación del diagnóstico reside en la profilaxis que puede efectuarse para tratar de evitar las lesiones mutilantes características de la enfermedad


Assuntos
Pré-Escolar , Humanos , Masculino , Feminino , Eritropoese , Porfirias/congênito , Dermatopatias , Diagnóstico Diferencial , Porfirinas/análise
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