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1.
Helminthologia ; 58(3): 323-327, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34934394

RESUMO

The European polecat (Mustela putorius Linnaeus, 1758) is in decline in Romania, often living near human settlements, from mountains to lowlands. They feed on a wide variety of small animals, including rodents, such as mice or rats. The occurrence of this parasite in polecats from Romania was mentioned only once in 1991, but the parasite species was not confirmed by molecular biology. The study aimed to investigate the occurrence of Trichinella spp. in European polecats from Romania and to identify the parasite species by molecular tools. A total of 75 wild European polecats were examined by trichinoscopy and artificial digestion. A large number of animals were examined because of their wide distribution in Romanian territory and their presence near human settlements. For species determination, the positive muscle samples and the larvae recovered from artificial digestion were collected for DNA isolation and further processed by means of Multiplex PCR. Only two polecats from southern Romania tested positive for Trichinella spp. infection. During trichinoscopy examination, 48 (in a polecat from Giurgiu County) and 78 (in a polecat from Ialomița County) cysts were found in the tested (56 samples/animal) tissue samples. Artificial digestion revealed infection with 2466 larvae/100 g of muscle in the polecat from Ialomița and 254/100 g in the polecat from Giurgiu. The Multiplex PCR indicated the occurrence of Trichinella spiralis in the polecat from Giurgiu and a co-infection with T. spiralis and T. britovi in the polecat from Ialomița. The current study confirms through molecular biology, the occurrence of T. spiralis and T. britovi, as well as the occurrence of co-infection with these two Trichinella species in European polecats from Romania.

2.
Med Vet Entomol ; 33(4): 530-535, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31280502

RESUMO

Hippobosca longipennis (Diptera: Hippoboscidae), the dog fly or dog louse fly, is an obligate blood-feeding ectoparasite of wild and domestic carnivores in Africa and the Middle East. Outside its typically known geographic range, H. longipennis has been reported occasionally on mainly domestic dogs in Asia and southern Europe, and infrequently in other areas (central Europe and the U.S.A.). This paper presents the first report of H. longipennis in Romania and the second record of Lipoptena fortisetosa (Diptera: Hippoboscidae), a potentially invasive species. Hippobosca longipennis was found on domestic dogs in two regions of the country (northern Romania in Maramures and southwestern Romania in Dobrogea) and on two road-killed wildcats in Maramures. Lipoptena fortisetosa was found on domestic dogs in Maramures. In both species identification was based on morphology and confirmed by barcoding of the cytochrome c oxidase subunit 1 gene. It is not clear for how long H. longipennis has been present in central Europe, nor if it was introduced (via the movement of domestic dogs or import of exotic carnivores) or present historically (Holocene remnants). This paper discusses the possible origins of H. longipennis in central Europe as its current distribution in the area is sparse and patchy.


Assuntos
Distribuição Animal , Dípteros/fisiologia , Doenças do Cão/parasitologia , Ectoparasitoses/veterinária , Animais , Cães , Ectoparasitoses/parasitologia
3.
Parasitology ; 144(14): 1922-1930, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28805181

RESUMO

Nematodes of the Angiostrongylidae family, such as Angiostrongylus vasorum and Angiostrongylus cantonensis, may cause potentially life-threatening diseases in several mammal species. Alongside these well-known species, Angiostrongylus chabaudi has been recently found affecting the cardiopulmonary system of domestic and wild cats from Italy, Germany, Greece, Romania and Bulgaria. Nonetheless, significant gaps in the understanding of A. chabaudi epidemiology include the lack of information of species acting as intermediate host and of the morphological description of larval stages. Cornu aspersum (n = 30) land snails were infected with 100 first-stage larvae of A. chabaudi collected from a naturally infected wildcat in Romania. Larvae at different developmental stages were found in 29 out of 30 (96·7%) infected snails and a total of 282 (mean 9·8 ± 3·02 larvae per each specimen) were collected from the gastropods. Here we demonstrate that A. chabaudi develops in snails and report C. aspersum as potential intermediate host for this parasitic nematode. Findings of this study are central to understand the ecological features of feline angiostrongylosis and its epidemiology within paratenic and intermediate hosts.


Assuntos
Angiostrongylus/crescimento & desenvolvimento , Doenças do Gato/parasitologia , Interações Hospedeiro-Parasita , Caramujos/parasitologia , Infecções por Strongylida/veterinária , Animais , Gatos , Larva/crescimento & desenvolvimento , Romênia , Infecções por Strongylida/parasitologia
4.
Nephron Clin Pract ; 117(4): c373-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21071961

RESUMO

BACKGROUND: Resistance to erythropoiesis-stimulating agents (ESAs) has been observed in patients with chronic kidney disease (CKD) and it is associated with clinical outcomes. The presence of ESA resistance cannot always be explained by the known risk factors of the condition, suggesting that additional factors may be involved. We wanted to test the hypothesis that vitamin D insufficiency is associated with lower hemoglobin (Hb) and ESA resistance in patients on maintenance hemodialysis (HD). METHODS: Data from patients receiving maintenance HD in a single dialysis center were extracted from the medical records in a retrospective chart review. Basic patient characteristics and laboratory data including Hb, serum albumin, intact parathyroid hormone and serum 25(OH)-cholecalciferol (25(OH)D(3)) levels were collected. ESA dose and Kt/V were extracted from the dialysis charts. Correlation analysis and multivariate linear regression analysis were used to reveal potential independent associations between clinical and laboratory parameters and ESA resistance. RESULTS: Data from 142 patients were analyzed. Serum 25(OH)D(3) concentration was significantly correlated with Hb (ρ = 0.186, p < 0.05) and also with ESA dose/Hb index (ρ = 0.230, p < 0.01). In multivariable regression analyses, serum 25(OH)D(3) concentration remained significantly associated with both Hb and ESA dose/Hb index after controlling for potentially important confounders. CONCLUSION: Serum 25(OH)D(3) concentration is independently associated with erythropoietin responsiveness in CKD patients on maintenance HD. If this association will be confirmed, treatment trials looking at the effect of vitamin D supplementation on anemia treatment in CKD patients may be warranted.


Assuntos
Calcifediol/sangue , Hematínicos/uso terapêutico , Hemoglobinas/metabolismo , Falência Renal Crônica/sangue , Diálise Renal , Adulto , Idoso , Biomarcadores/sangue , Estudos Transversais , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico
6.
Eye (Lond) ; 24(6): 962-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19911018

RESUMO

PURPOSE: To evaluate long-term morphologic and functional changes after intravitreal ranibizumab in avascular pigment epithelial detachment (PED) secondary to age-related macular degeneration (AMD). PATIENTS AND METHODS: Interventional, prospective case series; the first group of six patients received three and the second group of six patients received six intravitreal injections of ranibizumab (0.5 mg) at monthly intervals. Outcome measures included the change of PED and retinal volume as determined by spectral domain optical coherence tomography (Cirrus), best-corrected visual acuity (BCVA; Early Treatment Diabetic Retinopathy Study), and macular sensitivity using microperimetry (MP-1; Nidek Co. Ltd). RESULTS: The mean baseline PED volume of 1.33 mm3 decreased significantly by 42% at month 6 (-0.55 mm3, P<0.05). Compared to baseline no significant change was observed at months 9 and 12. BCVA, retinal volume, and macular sensitivity remained stable during the entire follow-up. In one case a tear of the retinal pigment epithelium was observed after five injections with a consequent decrease of BCVA of four lines. CONCLUSION: Treatment with intravitreal injections of ranibizumab may temporarily decrease the volume of avascular PED secondary to AMD, however this effect was not maintained over the 1-year study period. The treatment was ineffective for improving retinal function as measured with BCVA and microperimetry.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Descolamento Retiniano/tratamento farmacológico , Epitélio Pigmentado da Retina , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Feminino , Humanos , Injeções Intravítreas , Degeneração Macular/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Ranibizumab , Retina/patologia , Descolamento Retiniano/etiologia , Descolamento Retiniano/patologia , Tomografia de Coerência Óptica , Acuidade Visual
7.
Br J Ophthalmol ; 93(11): 1453-60, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19520692

RESUMO

AIMS: To evaluate the reliability of different optical coherence tomography (OCT) devices and scanning patterns in the assessment of retinal thickness and segmentation performance in neovascular age-related macular degeneration (nAMD). METHODS: 28 eyes with nAMD and 10 healthy eyes were imaged using conventional time domain (TD) OCT as well as three spectral-domain (SD) OCT systems. Radial scans of 6 mm in size were compared between Stratus and Topcon OCT, in addition to raster scans of all three SD-OCT devices. Retinal thickness values were analysed. RESULTS: Spectralis SD-OCT demonstrated the highest values of all OCT devices in central millimetre thickness (CMMT), and Topcon OCT raster scans showed the lowest values. Significant correlations could be found between the CMMT measurements of Cirrus and Spectralis OCT (r = 0.87). Analyses showed best segmentation for Cirrus and Spectralis SD-OCTs. Cirrus 200x200x1024 scans showed 4% and Stratus OCT 38% moderate or severe segmentation errors. CONCLUSION: Retinal thickness values were generally higher in SD-OCT analysis. Different performances of automatic retinal thickness analysis indicate the potential of different software algorithms to quantify retinal morphology in nAMD. Further development of current algorithms may improve quantification of retinal thickness detection in the future even further.


Assuntos
Degeneração Macular/patologia , Retina/patologia , Tomografia de Coerência Óptica/métodos , Idoso , Algoritmos , Feminino , Humanos , Masculino
8.
Clin Nephrol ; 64(4): 288-94, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16240900

RESUMO

AIMS: An increasing amount of evidence suggests that 25-hydroxy vitamin D3 (25(OH)D3) may contribute to the bone health of patients with chronic kidney disease (CKD). The underlying vitamin D status of these patients, however, has often been neglected. In a cross-sectional study we assessed the association between vitamin D status and parathyroid function, bone turnover, bone mass and structure in patients on maintenance hemodialysis. METHODS: 69 patients on maintenance hemodialysis were assessed by bone densitometry (DEXA) and quantitative bone ultrasound (QUS). Serum 25-hydroxy vitamin D3 levels, serum markers of bone turnover and clinical data were tabulated. RESULTS: A high prevalence of potentially significant vitamin D3 deficiency was found in this patient group: 59% of the patients had a 25(OH)D3 level below 20 nmol/l. There was a significant negative correlation between serum 25(OH)D3 levels and serum intact parathyroid hormone (iPTH) (r = -0.231, p < 0.05), and this association remained significant after controlling for potential covariables. Furthermore, we show here that serum 25(OH)D3 concentration is positively correlated with bone mineral density (BMD) measured at the radius (r = 0.424, p < 0.01). Finally, we show for the first time that 25(OH)D3 levels are significantly and independently correlated with broadband ultrasound attenuation (beta = 0.262, p < 0.05) measured with calcaneal quantitative bone ultrasound (QUS) in patients with chronic renal failure. CONCLUSION: Vitamin D3 deficiency may contribute to the impaired bone health of patients on maintenance dialysis.


Assuntos
Densidade Óssea/fisiologia , Calcifediol/sangue , Falência Renal Crônica/sangue , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Progressão da Doença , Feminino , Colo do Fêmur/diagnóstico por imagem , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Ultrassonografia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etiologia
9.
J Mass Spectrom ; 36(12): 1312-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11754123

RESUMO

A post-source decay matrix-assisted laser desorption/ionization mass spectrometric (PSD-MALDI-MS) study of rutin, a naturally occurring flavone glycoside cationized with different alkali metal ions, is reported. The fragmentations of rutin were performed by selecting the [R + Cat]+ peaks for PSD, where R represents a rutin molecule and Cat an alkali metal ion (Li+, Na+, K+). The PSD-MALDI mass spectra showed, depending on Cat, different fragmentation patterns with respect to both the quality and quantity of the fragment ions formed. The intensity of fragmentation decreased in the order Li+ > Na+ > K+. The fragmentation mechanism and an explanation for the observed differences are suggested.


Assuntos
Metais Alcalinos/química , Rutina/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Cátions , Lítio/química , Estrutura Molecular , Potássio/química , Ramnose/química , Sódio/química
10.
Orv Hetil ; 142(22): 1165-7, 2001 Jun 03.
Artigo em Húngaro | MEDLINE | ID: mdl-11424591

RESUMO

The case of a 53-year-old woman with headache and progressive right sided decline of visual acuity is reported. Computed tomography scans of the brain revealed multiple circumscribed foci of mineralization located over the left frontal and parietal, as well as the right central brain parenchyma. Surgical sampling of the left frontal lesion yielded a conglomerate composed of mineralized vessels, myriad of psammoma bodies, and metaplastic lamellar bone entangled within poorly cellular collagen fibers. No evidence was found of an underlying vascular malformation or tumor, nor was there evidence of parenchymal necrosis of infectious origin. On account of the organoid association of the mesenchymal elements and the mineralized moiety, the lesion was consistent with fibro-osseous lesion of the central nervous system. Also known as "calcifying pseudotumor" of the brain, the origin of this exceedingly rare condition is, as yet, unknown. By analogy, its pathogenesis is likely to involve mechanisms underlying tumoral calcinosis of soft tissues.


Assuntos
Osso e Ossos , Encefalopatias/diagnóstico , Encéfalo/patologia , Calcinose/diagnóstico , Coristoma/diagnóstico , Encefalopatias/complicações , Calcinose/complicações , Coristoma/complicações , Diagnóstico Diferencial , Feminino , Fibrose/complicações , Fibrose/diagnóstico , Cefaleia/etiologia , Humanos , Pessoa de Meia-Idade , Transtornos da Visão/etiologia
11.
Rapid Commun Mass Spectrom ; 15(9): 675-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11319788

RESUMO

The possibility of using copper(I) chloride as a doping salt to enhance the cationization of polystyrene in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was investigated. It was shown that copper(I) chloride possesses sufficient solubility in tetrahydrofuran. The parameters of the MALDI mass spectra of different polystyrene samples, such as the number-average (M(n)) and mass-average (M(w)) molecular mass values, obtained by copper(I) cationization were compared with those obtained by means of silver(I) cationization, and good agreement was found. It was also shown that application of copper(I) chloride as a doping salt, and dithranol as a matrix, ensured good MALDI mass spectra of the sample spots even after storage for 1 month.

12.
J Inorg Biochem ; 83(2-3): 107-14, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11237249

RESUMO

Interaction between iron(II) and acetohydroxamic acid (Aha), alpha-alaninehydroxamic acid (alpha-Alaha), beta-alaninehydroxamic acid (beta-Alaha), hexanedioic acid bis(3-hydroxycarbamoyl-methyl)amide (Dha) or desferrioxamine B (DFB) under anaerobic conditions was studied by pH-metric and UV-Visible spectrophotometric methods. The stability constants of complexes formed with Aha, alpha-Alaha, beta-Alaha and Dha were calculated and turned out to be much lower than those of the corresponding iron(II) complexes. Stability constants of the iron(II)-hydroxamate complexes are compared with those of other divalent 3d-block metal ions and the Irving-Williams series of stabilities was found to be observed. Above pH 4, in the reactions between iron(II) and desferrioxamine B, the oxidation of the metal ion to iron(III) by the ligand was found. The overall reaction that resulted in the formation of the tris-hydroxamato complex [Fe(HDFB)]+ and monoamide derivative of DFB at pH 6 is: 2Fe2+ + 3H4DFB+ = 2[Fe(HDFB)]+ + H3DFB-monoamide+ + H2O + 4H+. Based on these results, the conclusion is that desferrioxamine B can uptake iron in iron(III) form under anaerobic conditions.

13.
Acta Pharm Hung ; 71(2): 153-6, 2001 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-11862662

RESUMO

Status epilepticus is one of the most common neurologic emergencies in children, adolescents, and young adults. The advantage of diazepam suppository in medicinal therapy appears mainly in treatment of childhood epilepsy. A hydrophilic suppository base was investigated in solution by dynamic light scattering and results were compared to those of the membrane diffusion experiments measuring diazepam solubilization. According to the dynamic laser light scattering photometric measurements, the good solubilization effect of the macrogol mixture (5% Polysorbatum 20, 10% Macrogolum 400, 85% Macrogolum 1540) is explained by the formation of small, tight micellas. As the Polysorbatum 20 tenside resulted in the significant decrease (p < 0.05) of the formation of great micellas, its use led to the formation of small, tight, almost monodisperse micellas of 40-50 nm in the aqueous solution of the macrogol mixture.


Assuntos
Lasers , Polietilenoglicóis/química , Espalhamento de Radiação , Diazepam/química , Excipientes , Soluções , Supositórios
14.
J Child Lang ; 28(3): 787-804, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11797548

RESUMO

Two experiments investigated why preschool children sometimes produce multiple words for a referent (i.e. polynomy), but other times seem to allow only one word. In Experiment 1, 40 three- and four-year-olds completed a modification of Deák & Maratsos' (1998) naming task. Although social demands to produce multiple words were reduced, children produced, on average, more than two words per object. Number of words produced was predicted by receptive vocabulary. Lexical insight (i.e. knowing that a word refers to function or appearance) and metalexical beliefs (i.e. that a hypothetical referent has one label, or more than one) were not preconditions of polynomy. Polynomy was independent of bias to map novel words to unfamiliar referents. In Experiment 2, 40 three- and four-year-olds learned new words for nameable objects. Children showed a correction effect, yet produced more than two words per object. Children do not have a generalized one-word-per-object bias, even during word learning. Other explanations (e.g. contextual restriction of lexical access) are discussed.


Assuntos
Linguagem Infantil , Comportamento Verbal , Pré-Escolar , Feminino , Humanos , Masculino , Distribuição Aleatória
15.
J Colloid Interface Sci ; 229(2): 550-553, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10985835

RESUMO

The photochemical synthesis of Ag(0) nanoparticles in the presence of amino- and carboxylate-terminated PAMAM dendrimers is reported. The formation of Ag(0) nanoparticles was followed spectrophotometrically and by transmission electron microscopy (TEM). According to TEM investigations Ag(0) nanoparticles with the average size of about 7 nm in diameter were produced. Based on the present investigation a possible mechanism for the Ag(0) nanoparticles formation is proposed. Copyright 2000 Academic Press.

16.
Dev Psychol ; 36(4): 511-23, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10902702

RESUMO

Factors affecting joint visual attention in 12- and 18-month-olds were investigated. In Experiment 1 infants responded to 1 of 3 parental gestures: looking, looking and pointing, or looking, pointing, and verbalizing. Target objects were either identical to or distinctive from distractor objects. Targets were in front of or behind the infant to test G. E. Butterworth's (1991b) hypothesis that 12-month-olds do not follow gaze to objects behind them. Pointing elicited more episodes of joint visual attention than looking alone. Distinctive targets elicited more episodes of joint visual attention than identical targets. Although infants most reliably followed gestures to targets in front of them, even 12-month-olds followed gestures to targets behind them. In Experiment 2 parents were rotated so that the magnitude of their head turns to fixate front and back targets was equivalent. Infants looked more at front than at back targets, but there was also an effect of magnitude of head turn. Infants' relative neglect of back targets is partly due to the "size" of adult's gesture.


Assuntos
Atenção , Gestos , Comportamento Imitativo , Comportamento do Lactente , Orientação , Percepção Visual , Adulto , Fatores Etários , Sinais (Psicologia) , Feminino , Humanos , Lactente , Masculino , Relações Pais-Filho , Percepção Espacial
17.
Dev Psychol ; 34(2): 224-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9541775

RESUMO

Applying several names to an entity (polynomy) reflects the ability to categorize entities in different ways. Two experiments demonstrate preschoolers' abilities to apply multiple labels to representational objects and to people. In Experiment 1, 3- and 4-year-olds labeled representational objects and verified labels for story characters. In both tasks children reliably produced or accepted several words per entity and accepted a high percentage of both class-inclusive and overlapping word pairs. These results were replicated in Experiment 2; 3- to 5-year-olds also completed appearance-reality and receptive vocabulary tests. The mean number of words produced in the labeling task was significantly related to receptive vocabulary, but not to appearance-reality performance. The results indicate that preschoolers represent an entity as belonging to multiple categories (e.g., dinosaur and crayon). Implications for cognitive and language development, particularly the appearance-reality distinction and the mutual exclusivity bias, are discussed.


Assuntos
Cognição , Desenvolvimento da Linguagem , Terminologia como Assunto , Comportamento Infantil , Pré-Escolar , Feminino , Humanos , Masculino
18.
Orv Hetil ; 138(50): 3185-8, 1997 Dec 14.
Artigo em Húngaro | MEDLINE | ID: mdl-9446084

RESUMO

The authors report the case of an arrhythmogen right ventricular cardiomyopathy. The disease is characterised by the partial or total loss and the fibro-fatty replacement of right ventricular musculature and by the higher familiar incidence. The clinical importance of the disease is the malignant ventricular arrhythmia generated in the right ventricular wall, that is often fatal. Right heart failure is less frequent and develops mainly preterminally. The curiosity of this case is right atrial and ventricular thrombi diagnostized concomitantly with progressive heart failure. This combination is a rarity in medical literature, in contrast with the disease itself, as it was previously supposed. Early diagnosis, pharmacological and non-pharmacological treatment can reduce the fatal outcome.


Assuntos
Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Hipertrofia Ventricular Direita/diagnóstico por imagem , Adulto , Displasia Arritmogênica Ventricular Direita/patologia , Função do Átrio Direito , Ecocardiografia , Evolução Fatal , Humanos , Hipertrofia Ventricular Direita/patologia , Masculino , Trombose/diagnóstico por imagem , Trombose/patologia , Disfunção Ventricular Direita
19.
Child Dev ; 67(3): 740-67, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8706524

RESUMO

The present research explored the effects of stimulus and task factors on preschoolers' (Experiments 1 and 3) and adults' (Experiment 2) tendency to categorize according to taxonomic relations, when those relations conflict with appearances. In Experiment 1, we examined the effects of and interactions among (a) available information, operationalized by using more- or less-informative stimulus types (objects vs. line drawings) and by the presence or absence of labeling, and (b) task constraints, operationalized by comparing sorting questions with inductive inferences questions. When provided with information that constrained the categorization decision, either through the availability of labels or a combination of enhanced physical informativeness of objects and an inference question, preschoolers reliably based their categorization decisions on taxonomic relations between physically dissimilar items. In Experiment 2, stimulus type (objects vs. line drawings) was shown to have a similar effect on adults. In Experiment 3, we examined the effects of stimulus type on preschoolers' inductive inferences and accuracy of naming. The effects in the two tasks were closely related, suggesting that the amount of available information affects different responses in similar ways. These data demonstrate the interactive effects of available information and task constraints on categorization decisions.


Assuntos
Desenvolvimento Infantil , Formação de Conceito , Aprendizagem por Discriminação , Reconhecimento Visual de Modelos , Resolução de Problemas , Adulto , Atenção , Pré-Escolar , Feminino , Humanos , Masculino , Aprendizagem Verbal
20.
J Exp Child Psychol ; 60(3): 393-427, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8551211

RESUMO

In experimental tasks in which subjects sort sets of objects with conflicting appearances and taxonomic relations, preschoolers often have been found to categorize according to appearance. The procedures used in past studies, however, may have biased preschoolers to attend to appearance instead of taxonomic relations. This possibility was examined in two experiments. In Experiment 1, children's preference for taxonomic- or appearance-based sorting was affected by both the training and the instructions they received. Adults in Experiment 1 were affected by instructions, but not by training. In Experiment 2 preschoolers sorted above chance according to the criterion for which they received training and instruction (taxonomic relations or appearance). Consistency data, children's justifications, and spontaneous labeling support the conclusions that training and instructions have a significant effect on children's preference to sort according to taxonomic relations or appearance, and that both criteria can be used systematically by children as young as four. Implications for task comprehension, flexibility, methodology, and education are discussed.


Assuntos
Pré-Escolar , Comportamento de Escolha , Cognição , Análise e Desempenho de Tarefas , Adulto , Desenvolvimento Infantil , Feminino , Humanos , Masculino
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