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1.
Bull Entomol Res ; 106(2): 242-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26786247

RESUMO

Ground beetle data were generated using pitfall traps in the 17-year period from 1993 to 2009 and used to investigate the effects of changes in surrounding crop cover on beetle activity and assemblages, together with the effects of weather variability. Beetles were recorded from non-crop field margins (overgrown hedges). Crop cover changes explained far more variation in the beetle assemblages recorded than did temperature and rainfall variation. A reduction in management intensity and disturbance in the crops surrounding the traps, especially the introduction and development of willow coppice, was concomitant with changes in individual species activity and assemblage composition of beetles trapped in non-crop habitat. There were no consistent patterns in either overall beetle activity or in the number of species recorded over the 17-year period, but there was a clear change from assemblages dominated by smaller species with higher dispersal capability to ones with larger beetles with less dispersal potential and a preference for less disturbed agroecosystems. The influence of surrounding crops on ground beetle activity in non-crop habitat has implications for ecosystem service provision by ground beetles as pest predators. These results are contrary to conventional assumptions and interpretations, which suggest activity of pest predators in crops is influenced primarily by adjacent non-crop habitat. The long-term nature of the assessment was important in elucidation of patterns and trends, and indicated that policies such as agri-environment schemes should take cropping patterns into account when promoting management options that are intended to enhance natural pest control.


Assuntos
Besouros/fisiologia , Produtos Agrícolas/crescimento & desenvolvimento , Animais , Besouros/classificação , Ecossistema , Temperatura , Tempo (Meteorologia)
2.
Mol Ecol ; 14(6): 1811-20, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15836652

RESUMO

Bumblebees are major pollinators of crops and wildflowers in northern temperate regions. Knowledge of their ecology is vital for the design of effective management and conservation strategies but key aspects remain poorly understood. Here we employed microsatellite markers to estimate and compare foraging range and nest density among four UK species: Bombus terrestris, Bombus pascuorum, Bombus lapidarius, and Bombus pratorum. Workers were sampled along a 1.5-km linear transect across arable farmland. Eight or nine polymorphic microsatellite markers were then used to identify putative sisters. In accordance with previous studies, minimum estimated maximum foraging range was greatest for B. terrestris (758 m) and least for B. pascuorum (449 m). The estimate for B. lapidarius was similar to B. pascuorum (450 m), while that of B. pratorum was intermediate (674 m). Since the area of forage available to bees increases as the square of foraging range, these differences correspond to a threefold variation in the area used by bumblebee nests of different species. Possible explanations for these differences are discussed. Estimates for nest density at the times of sampling were 29, 68, 117, and 26/km2 for B. terrestris, B. pascuorum, B. lapidarius and B. pratorum, respectively. These data suggest that even among the most common British bumblebee species, significant differences in fundamental aspects of their ecology exist, a finding that should be reflected in management and conservation strategies.


Assuntos
Abelhas/fisiologia , Comportamento Alimentar/fisiologia , Genética Populacional , Comportamento de Nidação/fisiologia , Comportamento Espacial/fisiologia , Animais , Abelhas/genética , Conservação dos Recursos Naturais , Genótipo , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Densidade Demográfica , Especificidade da Espécie , Reino Unido
3.
J Natl Cancer Inst ; 85(6): 488-93, 1993 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-8445677

RESUMO

BACKGROUND: Hematopoietic growth factors (HGFs) have been shown to reduce the incidence of neutropenia and fever in patients receiving cancer chemotherapy. PURPOSE: This cost analysis was designed to determine the conditions in which use of HGFs in patients receiving cancer chemotherapy is cost-effective. METHODS: We used a standard model based on decision theory; the model assumes that all patients experiencing neutropenia and fever will be hospitalized and treated with intravenous antibiotics. Data from a prospective, randomized clinical trial of granulocyte colony-stimulating factor in small-cell lung cancer treated with combination chemotherapy were used to determine baseline probabilities for control hospitalization risk and survival; proportional hospitalization risk with prophylactic HGF; and median durations of hospitalization and prophylactic HGF use. The model was analyzed by one-way and multivariate sensitivity analyses, with estimation of threshold values at which the expected cost is the same for either of two treatment options. One or more of the specific costs and durations and the probability for each group of threshold curves were varied in a sensitivity analysis that generated variable thresholds. Use of Monte Carlo analysis based on the available distributions of the main variables provided 90% confidence limits and an inference method for comparing decision options. RESULTS: The expected excess cost per treatment cycle, based on hospitalization for neutropenic fever and/or HGF administration, was $5500 for no HGF, $4750 for prophylactic HGF, and $6875 for therapeutic HGF. Sensitivity analysis provided the following thresholds for no HGF versus prophylactic HGF: control risk of hospitalization, 0.40; risk of hospitalization with HGF as a proportion of control, 0.64; total daily cost of hospitalization, $727; total daily cost of HGF, $344; duration of hospitalization, 7.3 days; and duration of HGF use, 11.0 days. Multivariate analysis revealed that conditions favoring the use of HGF on a cost basis become greater (a) as risk of hospitalization, total daily hospital cost, and duration of hospitalization increase and (b) as the proportional risk of hospitalization with HGF, daily cost of HGF, and duration of HGF treatment decrease. CONCLUSIONS: The major determinants of total excess cost were the control risk of hospitalization, the proportional reduction in risk with HGF, and the average daily hospital cost. IMPLICATIONS: Use of HGFs should be based on the risk of hospitalization for neutropenic fever and consideration of the patient population and institutional costs.


Assuntos
Fatores Estimuladores de Colônias/uso terapêutico , Técnicas de Apoio para a Decisão , Neoplasias/tratamento farmacológico , Neutropenia/prevenção & controle , Análise Custo-Benefício , Febre/prevenção & controle , Custos de Cuidados de Saúde , Hospitalização , Humanos
4.
J Nucl Med ; 29(12): 2001-3, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3193212

RESUMO

Under ordinary circumstances a toddler's fracture of the lower extremity is diagnosed by clinical evaluation and history. Often the initial conventional radiograph is unrevealing, but the fracture is diagnosed and treated based on appropriate clinical and laboratory findings. In rare instances, a patient with an unsuspected toddler's fracture may present with an atypical history, unusual physical findings, or laboratory values suggesting the presence of an inflammatory process. Skeletal scintigraphy in this small group of patients has been valuable in defining a spiral fracture of the midshaft of the tibia connected with a toddler's fracture. We report the scintigraphic appearance from the findings in six patients with unsuspected toddler's fracture evaluated by this method.


Assuntos
Fraturas Ósseas/diagnóstico por imagem , Traumatismos da Perna/diagnóstico por imagem , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Cintilografia , Medronato de Tecnécio Tc 99m
5.
Lancet ; 2(8362): 1277-80, 1983 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-6139621

RESUMO

A two-year study of 51 women has shown a highly significant relation between high counts of fastidious organisms in the urine and the presence of symptoms. The patients, even when symptom-free, differed in this respect from a control group who had not had urinary symptoms for 2 years and from a group on long-term low-dose prophylaxis for recurrent urinary infection. The history, physical signs, and natural history of urinary symptoms in these patients were consistent with a diagnosis of urethral or paraurethral infection.


Assuntos
Bactérias/isolamento & purificação , Doenças Uretrais/microbiologia , Infecções Urinárias/microbiologia , Adolescente , Adulto , Idoso , Bacteriúria/microbiologia , Criança , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva , Síndrome , Doenças Uretrais/diagnóstico , Infecções Urinárias/diagnóstico , Infecções Urinárias/prevenção & controle
6.
Cancer Res ; 41(5): 1763-71, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-6260350

RESUMO

This study was undertaken to examine relationships of the phenotype of malignant cells to target cell properties and to events early in the transformation process. Eighteen transformed lines were obtained by Kirsten murine sarcoma virus infection of cells from adrenal glands of rats ages 4 to 30 weeks, at first or second passages in culture. They were grown either as fibroblastic adrenocortical stem cells or as more differentiated epithelial cells, depending on culture conditions. Of 14 lines examined for their capacity to synthesize corticosteroids, 11 converted [14C]pregnenolone to progesterone, and one converted to deoxycorticosterone. In vivo, seven lines produced tumors resembling pleomorphic carcinomas, six lines grew as sarcomas, four grew as mixed tumors, and one line produced anaplastic tumors. Distinguishing features in culture of the carcinoma-producing lines were early onset and rapid progression of morphological transformation, a noncohesive epithelial cell form in some lines, lack of extracellular matrix, and, possibly, and origin in older animals. In contrast, sarcoma-producing cells were fibroblastic and cohesive, produced extracellular matrix, and transformed morphologically after longer and less well-defined periods in culture. The variation in histopathology was unrelated to the differentiation of the target cells and to the capacity of the transformed cells to synthesize corticosteroids. The results show that adrenocortical cells, transformed by Kirsten murine sarcoma virus after short-term culture, usually retain some functional differentiation and sometimes resemble human adrenocortical carcinomas histologically. The susceptibility of adrenocortical cells to Kirsten murine sarcoma virus raises the possibility that mesodermally derived epithelia in general may be target tissues for C-type sarcoma viruses.


Assuntos
Córtex Suprarrenal/microbiologia , Transformação Celular Viral , Vírus do Sarcoma Murino de Kirsten , Vírus do Sarcoma Murino , Córtex Suprarrenal/patologia , Corticosteroides/biossíntese , Neoplasias do Córtex Suprarrenal/microbiologia , Animais , Diferenciação Celular , Células Cultivadas , Epitélio/patologia , Espaço Extracelular , Masculino , Transplante de Neoplasias , Neoplasias Experimentais/patologia , Pregnenolona/metabolismo , Ratos
7.
Clin Orthop Relat Res ; (113): 27-35, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-811419

RESUMO

The response of skeletal muscle to ischemia or trauma is similar whatever the mechanism of injury. Muscle has much more inherent ability to regenerate than has been recognized in the past. The extent of muscle damage is proportional to the duration and severity of the ischemic process. Circulation to ischemis muscle must be re-established as soon as possible. Early decompression of the appropriate compartemnts is an essential part of this procedure. No attempt should be made to excise muscle of doubtful or unknown viability during the initial decompression operation.


Assuntos
Isquemia/patologia , Músculos/patologia , Doenças Musculares/patologia , Adulto , Animais , Síndrome do Compartimento Anterior/patologia , Modelos Animais de Doenças , Haplorrinos , Humanos , Macrófagos , Músculos/irrigação sanguínea , Músculos/ultraestrutura , Coelhos
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