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1.
J Am Acad Dermatol ; 87(3): 559-566, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35487332

RESUMO

BACKGROUND: The incidence of systemic lupus in children with discoid lupus is unknown. OBJECTIVE: This study assessed the baseline characteristics of patients with pediatric discoid lupus erythematosus (pDLE). METHODS: Medical records at 17 sites were reviewed for pediatric dermatology and rheumatology patients with discoid lupus erythematosus. The inclusion criteria were clinical and/or histopathologic diagnosis of discoid lupus erythematosus with an age at onset of <18 years. Baseline data were collected at the first documented visit. Outcomes included diagnosis of systemic lupus erythematosus (SLE) at the baseline visit using the 1997 American College of Rheumatology (primary) and the 2012 Systemic Lupus International Collaborating Clinics (secondary) criteria. RESULTS: Of the >1500 charts reviewed, 438 patients met the inclusion criteria. The cohort was predominantly female (72%) and racially/ethnically diverse. A diagnosis of SLE at the baseline visit (pDLE + SLE) was rendered in 162 (37%) patients using the American College of Rheumatology and in 181 (41%) patients using the Systemic Lupus International Collaborating Clinics criteria. Patients with pDLE + SLE were older at the time of rash onset (median, 12.9 vs 8.9 years; P < .001), with shorter time from discoid lupus erythematosus onset to diagnosis, compared with patients with pDLE-only (median, 2 vs 7 months; P < .001). Patients with pDLE + SLE were more likely to be female (P = .004), with generalized discoid lupus erythematosus and clinically aggressive disease, including end-organ involvement, positive serologies, and higher- titer levels of antinuclear antibodies (P < .001). LIMITATIONS: Retrospective study. CONCLUSION: A diagnosis of discoid lupus erythematosus in adolescence should prompt thorough screening for SLE.


Assuntos
Lúpus Eritematoso Discoide , Lúpus Eritematoso Sistêmico , Adolescente , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Lúpus Eritematoso Discoide/diagnóstico , Lúpus Eritematoso Discoide/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Estudos Retrospectivos
2.
Food Res Int ; 149: 110698, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600692

RESUMO

Docosahexaenoic acid (DHA, 22:6n-3) is an essential long chain polyunsaturated fatty acid associated with the development of the nervous system that has to be consumed by infants through breast milk or complementary food sources and which consumption is also usually inadequate in preschoolers. In this work, the in vitro bioaccessibility of DHA from two commercial infant formulas (8.9 and 9.1%) and two preschool children milks (6.9 and 7.2%), with similar DHA contents but formulated with different ingredients, was not improved by the presence of egg phospholipids in the product formulation. In addition, the importance of the choice of an age-appropriate in vitro digestion method was demonstrated by comparing the DHA bioaccessibility from the infant formulas by the Infogest 2.0 standardized method and a simulated digestion method specific for infants.


Assuntos
Ácidos Docosa-Hexaenoicos , Fórmulas Infantis , Pré-Escolar , Ácidos Graxos , Ácidos Graxos Insaturados , Feminino , Humanos , Lactente , Leite Humano
3.
Int J Sports Med ; 36(10): 789-95, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25958946

RESUMO

The purpose of this study was to assess the degree of transference of 6 weeks of full squat vs. full squat plus sprint running training to short (ranged from 0-10 to 0-30 m) sprint running performance in non-athletes. We hypothesized that a speed-full-squat training regimen could enhance squat strength and power with simultaneous improvements in short sprint performance. 122 physically active adults (age: 20.5±2.5 years; body mass: 65.8±6.1 kg; height: 1.71±0.08 m) were randomly divided into 4 groups: full squat training (n=36), combined full squat and sprint training (n=32), speed training only (n=34) and non-training control group (n=20). Each training group completed 2 sessions per week over 6 weeks, while the control group performed only their normal physical activity. Sprint performance was improved after sprint running or full squat training alone (1.7% and 1.8% P<0.05, respectively), however larger enhancements (2.3%; P<0.01) were observed after the combined full squat plus sprint training intervention. These results suggest that in recreationally active adults, combined full squat and sprint training provides a greater stimulus for improving sprint performance than either modality alone.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Treinamento Resistido/métodos , Corrida/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
4.
Scand J Med Sci Sports ; 25(2): e184-96, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24975756

RESUMO

The aim of this study was to analyze the changes in the hydrodynamic profile of young swimmers over a competitive season and to compare the variations according to a well-designed training periodization. Twenty-five swimmers (13 boys and 12 girls) were evaluated in (a) October (M1); (b) March (M2); and (c) June (M3). Inertial and anthropometrical measures included body mass, swimmer's added water mass, height, and trunk transverse surface area. Swimming efficiency was estimated by the speed fluctuation, stroke index, and approximate entropy. Active drag was estimated with the velocity perturbation method and the passive drag with the gliding decay method. Hydrodynamic dimensionless numbers (Froude and Reynolds numbers) and hull velocity (i.e., speed at Froude number = 0.42) were also calculated. No variable presented a significant gender effect. Anthropometrics and inertial parameters plus dimensionless numbers increased over time. Swimming efficiency improved between M1 and M3. There was a trend for both passive and active drag increase from M1 to M2, but being lower at M3 than at M1. Intra-individual changes between evaluation moments suggest high between- and within-subject variations. Therefore, hydrodynamic changes over a season occur in a non-linear fashion way, where the interplay between growth and training periodization explain the unique path flow selected by each young swimmer.


Assuntos
Desempenho Atlético/fisiologia , Hidrodinâmica , Natação/fisiologia , Adolescente , Fenômenos Biomecânicos , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Modelos Biológicos , Estações do Ano
5.
Food Funct ; 5(12): 3241-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25322288

RESUMO

Berries are an important dietary source of fibres, vitamins, minerals and some biologically active non-nutrients. A red raspberry fruit extract was characterized in terms of phenolic content and the anti-inflammatory properties and protective effects were evaluated in two experimental models of inflammation. The antioxidant potential of the extract, the cellular antioxidant activity and the effects over neutrophils' oxidative burst were also studied to provide a mechanistic insight for the anti-inflammatory effects observed. The extract was administered in a dose of 15 mg kg(-1), i.p. and significantly inhibited paw oedema formation in the rat. The same dose was administered via i.p. and p.o. routes in the collagen-induced arthritis model in the rat. The extract showed pharmacological activity and was able to significantly reduce the development of clinical signs of arthritis and markedly reduce the degree of bone resorption, soft tissue swelling and osteophyte formation, preventing articular destruction in treated animals.


Assuntos
Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Artrite/tratamento farmacológico , Edema/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Rosaceae/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Artrite/imunologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Edema/imunologia , Frutas/química , Humanos , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
6.
J R Soc Interface ; 11(91): 20130887, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24258156

RESUMO

Several studies have reported that fragmentation (e.g. of anthropogenic origin) of habitats often leads to a decrease in the number of species in the region. An important mechanism causing this adverse ecological impact is the change in the encounter rates (i.e. the rates at which individuals meet other organisms of the same or different species). Yet, how fragmentation can change encounter rates is poorly understood. To gain insight into the problem, here we ask how landscape fragmentation affects encounter rates when all other relevant variables remain fixed. We present strong numerical evidence that fragmentation decreases search efficiencies thus encounter rates. What is surprising is that it falls even when the global average densities of interacting organisms are held constant. In other words, fragmentation per se can reduce encounter rates. As encounter rates are fundamental for biological interactions, it can explain part of the observed diminishing in animal biodiversity. Neglecting this effect may underestimate the negative outcomes of fragmentation. Partial deforestation and roads that cut through forests, for instance, might be responsible for far greater damage than thought. Preservation policies should take into account this previously overlooked scientific fact.


Assuntos
Biodiversidade , Ecossistema , Dinâmica Populacional , Animais , Canadá , Conservação dos Recursos Naturais , Ecologia , Meio Ambiente , Agricultura Florestal , Modelos Biológicos , Modelos Estatísticos , Densidade Demográfica , Estrigiformes , Árvores
7.
Rev. bras. plantas med ; 16(3,supl.1): 750-754, 2014. graf
Artigo em Português | LILACS | ID: lil-727204

RESUMO

Muitas plantas são utilizadas pela população para o tratamento e a cura de doenças. Entre elas encontram-se a Persea major Kopp, Piper mollicomum Kunth. e Serjania erecta Radlk. as quais são utilizadas para diversas enfermidades, inclusive para tratar distúrbios do trato gastrointestinal. O objetivo deste trabalho foi estudar os efeitos dos extratos dessas três plantas sobre a motilidade gastrointestinal. Camundongos Swiss foram tratados com os extratos pela via oral 1 hora antes da administração de uma solução semisólida de carboximetilcelulose 1,5% e vermelho de fenol 0,05% e, após 15 minutos, o esvaziamento gástrico e o trânsito intestinal avaliados. O extrato hidroalcoólico da P. major (100 a 1000 mg Kg-1, p.o.) e o extrato hidroalcoólico da P. mollicomum (100 e 300 mg Kg-1, p.o.) aumentaram o trânsito intestinal. No entanto, somente o extrato da P. major (100 e 300 mg Kg-1) também aumentou o esvaziamento gástrico. O extrato etanólico da S. erecta (100 a 1000 mg Kg-1, p.o.) não alterou a motilidade gastrointestinal. Estes resultados sugerem que a Persea major e a Piper mollicomum mereçam estudos mais aprofundados em busca de princípios ativos ou matéria vegetal efetiva para o tratamento de distúrbios do trato gastrointestinal como a constipação.


Many plants are popularly used for the treatment and healing of diseases. The Persea major Kopp, Piper mollicomum Kunth. and Serjania erecta Radlk. are used in several illnesses, including the treatment of disorders of the gastrointestinal tract. The aim of this study was to evaluate the effects of the extracts of these plants on the gastrointestinal motility. Swiss mice were orally treated with extracts one hour before the administration of a semisolid solution of 1.5% carboxymethylcellulose and 0.05% phenol red. After 15 minutes, the gastric emptying and intestinal transit were determined. The hydroalcoholic extract of P. major (100 to 1000 mg Kg-1, p.o.) and the hydroalcoholic extract of P. mollicomum (100 and 300 mg Kg-1, p.o.) increased the intestinal transit. However, only the P. major extract (100 and 300 mg Kg-1) increased the gastric emptying. The ethanolic extract of S. erecta (100 to 1000 mg Kg-1, p.o.) did not alter the gastrointestinal motility. These results suggest that Persea major and Piper mollicomum can be of interest for further studies in the search of active principles or effective plant material for the treatment of disorders of the gastrointestinal tract, such as constipation.


Assuntos
Animais , Masculino , Feminino , Ratos , Plantas Medicinais/metabolismo , Extratos Vegetais/análise , Trato Gastrointestinal/fisiopatologia , Lauraceae/classificação , Piper/classificação , Esvaziamento Gástrico/fisiologia
8.
Int J Sports Med ; 34(10): 888-96, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23549693

RESUMO

The purpose of this study was to compare the effects of an 8-weeks training period of resistance training alone (GR), combined resistance and endurance training (GCON) and a control group (GC) on explosive strength and V(O2max) in a large sample of prepubescent boys and girls. 125 healthy children (58 boys, 67 girls), aged 10-11 years old (10.8±0.4 years) were assigned into 2 training groups to train twice a week for 8 weeks: GR (19 boys, 22 girls), GCON (21 boys, 24 girls) and a control group (GC: 18 boys, 21 girls; no training program). A significant but medium-sized increase from pre- to the post-training in the vertical jump (Effect size=0.22, F=34.44, p<0.01) and V(O2max) (Effect size=0.19, F=32.89, p<0.01) was observed. A significant large increase in the 1 kg (Effect size=0.53, F=202.17, p<0.01) and 3 kg (Effect size=0.48, F=132.1, p<0.01) ball throwing, standing long jump (Effect size=0.53, F=72.93, p<0.01) and running speed (Effect size=0.45, F=122.21, p<0.01) was also observed. The training group (GR and GCON) and sex factors did not significantly influence the evolution of strength variables from pre- to the post-training. The V(O2max) increased significantly only in GCON. Concurrent training is equally effective on training-induced explosive strength, and more efficient than resistance training only for V(O2max), in prepubescent boys and girls. This should be taken into consideration in order to optimize strength training school-based programs.


Assuntos
Força Muscular , Consumo de Oxigênio , Educação Física e Treinamento/métodos , Treinamento Resistido/métodos , Análise de Variância , Criança , Feminino , Voluntários Saudáveis , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Resistência Física , Aptidão Física , Corrida , Fatores Sexuais
9.
Scand J Med Sci Sports ; 21(5): 670-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21917018

RESUMO

Performance assessment has become an invaluable component of monitoring player development and within talent identification programs in soccer, yet limited performance data are available for female soccer players across a wide age range. The aim of this study was to describe the physical performance characteristics of female soccer players ranging in age from 12 to 21 years. High-level female soccer players (n=414) were evaluated on linear sprinting (36.6 m with 9.1 m splits), countermovement jump (CMJ), and two agility tests. Separate one-way ANOVAs were used to compare performance characteristics between (1) each year of chronological age and (2) three age groups: 12-13 years, n=78, 14-17 years, n=223, and 18-21 years, n=113. Mean linear sprint speed over 9.1 m was similar across all chronological ages, however sprint speed over the final 9.1 m, CMJ height and agility scores improved until approximately 15-16 years. Outcomes from the group data indicated better performance on all tests for the 14-17-year-old group compared with the 12-13-year-old group. Additionally, sprint speed on the second and fourth 9.1 m splits and 36.6 m sprint speed as well as performance on the Illinois agility test was better in the 18-21-year-old group compared with the 14-17-year-old group. The findings from this study indicate that marked improvements of high intensity short duration work occur up until 15-16 years. Smaller gains in performance were observed beyond 16 years of age as evidenced by better performance on 36.6 m sprint speed, several sprint splits and the Illinois agility test in the college aged players (i.e., 18-21-year-old group).


Assuntos
Futebol/fisiologia , Adolescente , Adulto , Fatores Etários , Análise de Variância , Desempenho Atlético , Criança , Teste de Esforço , Feminino , Humanos , Destreza Motora , Movimento , Corrida , Análise e Desempenho de Tarefas , Adulto Jovem
10.
Plant Biol (Stuttg) ; 10(5): 596-603, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18761498

RESUMO

Seasonal tropical forests show rhythms in reproductive activities due to water stress during dry seasons. If both seed dispersal and seed germination occur in the best environmental conditions, mortality will be minimised and forest regeneration will occur. To evaluate whether non-seasonal forests also show rhythms, for 2 years we studied the seed rain and seedling emergence in two sandy coastal forests (flooded and unflooded) in southern Brazil. In each forest, one 100 x 30-m grid was marked and inside it 30 stations comprising two seed traps (0.5 x 0.5 m each) and one plot (2 x 2 m) were established for monthly monitoring of seed rain and a seedling emergence study, respectively. Despite differences in soil moisture and incident light on the understorey, flooded and unflooded forests had similar dispersal and germination patterns. Seed rain was seasonal and bimodal (peaks at the end of the wetter season and in the less wet season) and seedling emergence was seasonal and unimodal (peaking in the wetter season). Approximately 57% of the total species number had seedling emergence 4 or more months after dispersal. Therefore, both seed dormancy and the timing of seed dispersal drive the rhythm of seedling emergence in these forests. The peak in germination occurs in the wetter season, when soil fertility is higher and other phenological events also occur. The strong seasonality in these plant communities, even in this weakly seasonal climate, suggests that factors such as daylength, plant sensitivity to small changes in the environment (e.g. water and nutrient availability) or phylogenetic constraints cause seasonal rhythms in the plants.


Assuntos
Ecossistema , Estações do Ano , Plântula/crescimento & desenvolvimento , Sementes , Clima Tropical , Brasil , Sementes/fisiologia , Água
11.
Plant Mol Biol ; 57(3): 375-91, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15830128

RESUMO

A functional genomics project has been initiated to approach the molecular characterization of the main biological and agronomical traits of citrus. As a key part of this project, a citrus EST collection has been generated from 25 cDNA libraries covering different tissues, developmental stages and stress conditions. The collection includes a total of 22,635 high-quality ESTs, grouped in 11,836 putative unigenes, which represent at least one third of the estimated number of genes in the citrus genome. Functional annotation of unigenes which have Arabidopsis orthologues (68% of all unigenes) revealed gene representation in every major functional category, suggesting that a genome-wide EST collection was obtained. A Citrus clementina Hort. ex Tan. cv. Clemenules genomic library, that will contribute to further characterization of relevant genes, has also been constructed. To initiate the analysis of citrus transcriptome, we have developed a cDNA microarray containing 12,672 probes corresponding to 6875 putative unigenes of the collection. Technical characterization of the microarray showed high intra- and inter-array reproducibility, as well as a good range of sensitivity. We have also validated gene expression data achieved with this microarray through an independent technique such as RNA gel blot analysis.


Assuntos
Citrus/genética , Etiquetas de Sequências Expressas , Genoma de Planta , Genômica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , DNA Complementar/química , DNA Complementar/genética , Perfilação da Expressão Gênica , Biblioteca Gênica , Dados de Sequência Molecular , RNA de Plantas/genética , RNA de Plantas/metabolismo , Reprodutibilidade dos Testes , Análise de Sequência de DNA
12.
Rev. bras. farmacogn ; 14(2): 121-127, 2004. tab
Artigo em Português | LILACS | ID: lil-570853

RESUMO

Stryphnodendron obovatum Benth., conhecido como "barbatimão", é uma espécie pertencente à família Leguminosae, sub-família Mimosoideae, e é amplamente distribuído em campos e cerrados. Na medicina popular, cascas de S. obovatum são usadas no tratamento de processos inflamatórios, como cicatrizante, para diarréia, frieira. Neste trabalho investigou-se a presença de proteínas e as atividades citotóxica, antibacteriana, antifúngica do extrato salino das sementes de S. obovatum. O extrato salino S. obovatum não apresentou toxidade frente ao ensaio com Artemia salina, nem mostrou atividade antibacteriana contra Staphylococcus aureus, Pseudomonas aeruginosa e Escherichia coli. Na avaliação da atividade antioxidante, o extrato salino apresentou uma CE50 de 12, 193 µg/mL, enquanto a do padrão positivo BHT foi 2,98 µg/mL. O extrato salino de S. obovatum não apresentou atividade antifúngica, tanto na técnica de bioautografia com o fungo Cladosporium sphaerospermum, quanto no método de difusão em disco, realizado com Candida albicans. Foi realizado teste de atividade enzimática na qual observou-se a hidrólise do substrato H-D-Benzoil-arginina-p-nitroanilida (Bz-Arg-pNan).


Stryphnodendron obovatum Benth., popularly known as "barbatimão", belongs to the Leguminosae fami/y, of the Mimosoideae subfamily, and is present in fields and in "cerrados". S. obovatum bark is used in popular medicine for treating inflammatory processes, for healing wounds, and as cure for diarrhea and chílblain. This research investigates the presence of proteins and the cytotoxic, antifungal, antibacterial and antioxidant activities of the S. obovatum seed saline extract. The saline extract did not show cytotoxicity against Artemia salina nor any antibacterial activíty against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia colí. The evaluation of the antioxidant activity showed a CEso=12.193 µg/mL, and the BHT positive pattern presented 2.98 µg/mL. The S. obovatum saline extract was tested against Cladosporium sphaerospermum and Candida albicans, using the bioautography technique and the disk diffusion method. Benzoyl­arginine-p-nitroanilide (Bz-Arg-pNan) was hydrolyzed by the saline extract.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(5 Pt 2): 056113, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12059653

RESUMO

We investigated the phase transition behavior of a binary spreading process in two dimensions for different particle diffusion strengths (D). We found that N>2 cluster mean-field approximations must be considered to get consistent singular behavior. The N=3,4 approximations result in a continuous phase transition belonging to a single universality class along the D subset (0,1) phase transition line. Large scale simulations of the particle density confirmed mean-field scaling behavior with logarithmic corrections. This is interpreted as numerical evidence supporting the bosonic field theoretical prediction that the upper critical dimension in this model is d(c)=2. The pair density scales in a similar way but with an additional logarithmic factor to the order parameter. At the D=0 end point of the transition line we found directed percolation criticality.

14.
Br J Pharmacol ; 135(5): 1324-30, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11877342

RESUMO

1. Adenosine is a regulator of mesenteric vasodilation involved in auto-regulation and post-prandial hyperemia, but the adenosine receptor subtype involved in this relaxant effect is poorly characterized. We have now pharmacologically characterized this receptor in rabbit mesenteric arteries and investigated how this adenosine receptor response changes in portal hypertensive animals since the adenosine response is decreased. 2. The closest non-metabolisable adenosine analogue, 2-chloroadenosine (CADO), the mixed A(1)/A(2) receptor agonist, 5'-ethylcarboxamidoadenosine (NECA), and the selective A(2A) receptor agonist, 2-[4-(2-p-carbonyethyl)phenylamino]-5'-N-ethylcarboxamidoadenosine (CGS 21680) (1 pM -- 1 mM) relaxed noradrenaline pre-contracted arteries with a rank order of potency of CGS 21680 (EC(50)=20 nM) > or = NECA (60 nM)>>CADO (640 nM). 3. The selective A(2A) receptor antagonist, 4-(2-[7-amino-2-(2-furyl)-[1,2,4]-triazolo[2,3-a][1,3,5]-triazin-5-ylamino]ethyl)phenol (ZM 241385, 100 nM), shifted to the right the CADO concentration-response curve. 4. In portal hypertensive animals, there was mainly a decreased potency but also a decreased efficacy of all tested adenosine agonists compared to normal animals. Concomitantly, there was a decreased adenosine plasma level and a decreased binding density of [(3)H]-CGS 21680 and [(3)H]-ZM 241385 to mesenteric artery membranes from portal hypertensive compared to normal rabbits. 5. These results indicate that A(2A) receptor activation is required for the adenosine-induced mesenteric relaxation and that the decreased density of A(2A) receptors may contribute to the decreased relaxation induced by adenosine of mesenteric arteries in portal hypertensive animals.


Assuntos
Adenosina/análogos & derivados , Hipertensão Portal/fisiopatologia , Artérias Mesentéricas/fisiologia , Receptores Purinérgicos P1/fisiologia , Vasodilatação/efeitos dos fármacos , Adenosina/farmacologia , Animais , Masculino , Agonistas do Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Coelhos , Receptor A2A de Adenosina , Receptores Purinérgicos P1/metabolismo , Vasodilatação/fisiologia
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(1 Pt 2): 016111, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11800740

RESUMO

Steady-state properties in the absorbing phase of the 1d pair contact process model are investigated. It is shown that, in typical absorbing states (reached by the system's dynamic rules), the density of isolated particles rho(1), approaches a stationary value that depends on the annihilation probability (p); the deviation from its "natural" value at criticality rho(nat)(1) follows a power law: rho(nat)(1)-rho(1) approximately (p-p(c))(beta(1)) for p>p(c). Monte Carlo simulations yield beta(1)=0.81. A cluster approximation is developed for this model, qualitatively confirming the numerical results and predicting beta(1)=1. The singular behavior of the isolated particles density in the inactive phase is explained using a phenomenological approach.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 2): 016104, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11461328

RESUMO

We investigate the critical behavior of a nonequilibrium system with two particle species A and B that exhibits a continuous absorbing-state phase transition. The number of particles of each species (N(A) and N(B)) is conserved by the dynamical process. Numerical results show that the order parameter exponent beta depends on the ratio N(B)/N(A) at criticality. Some aspects of critical dynamic behavior are also studied, namely, the decay of the active density at criticality and the critical spreading of a perturbation to an absorbing configuration. Anomalies in the relaxation are associated with the presence of different time scales in the dynamics of the model.

17.
Rev Lat Am Enfermagem ; 6(4): 83-93, 1998 Oct.
Artigo em Português | MEDLINE | ID: mdl-9823240

RESUMO

This article presents a process of investigation that was developed to identify life and health conditions of a community in order to propose changing strategies to the situation. It took place in Distrito do Grajaú (SP)--Brazil. All families were interviewed through the application of a survey in order to find personal/life conditions, and a health disease process profile. Data reveal a determined profile that was presented to the people to implement integrated actions to solve the main problems/issues at the community.


Assuntos
Participação da Comunidade , Saúde da Família , Indicadores Básicos de Saúde , Avaliação das Necessidades/organização & administração , Adolescente , Adulto , Distribuição por Idade , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Morbidade , Mortalidade , Fatores Socioeconômicos , Inquéritos e Questionários
18.
Eur Radiol ; 7(2): 198-201, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9038114

RESUMO

The objective of this study was to evaluate the appearance of localized giant cell tumour of the tendon sheath (GCTTS) on unenhanced and Gd-enhanced MR images. MR images of 13 histologically proven cases of localized GCTTS were evaluated for mean size, location, homogeneity and signal intensity (SI) on both T1- and T2-weighted images, and enhancement pattern. All lesions except 1 affected young adults. On T1- and T2-weighted images, lesions showed predominantly low SI equal to or slightly higher than skeletal muscle. On Gd-enhanced T1-weighted images, strong homogeneous enhancement was seen. These findings reflect the underlying histological composition of the lesion; haemosiderin deposition in xanthoma cells, shortening T2-relaxation time, and abundant collagenous proliferation are responsible for low SI on T1- and T2-weighted images. Strong homogeneous enhancement originates from numerous proliferative capillaries in the collagenous stroma. We conclude that these characteristic MR features, together with clinical information, are a valuable diagnostic tool in offering a correct preoperative diagnosis.


Assuntos
Imageamento por Ressonância Magnética , Sinovite Pigmentada Vilonodular/diagnóstico , Adolescente , Adulto , Criança , Feminino , Tumores de Células Gigantes/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Tendões/patologia
19.
Rev Port Cardiol ; 11(5): 431-7, 1992 May.
Artigo em Português | MEDLINE | ID: mdl-1520496

RESUMO

The cardiovascular response to carotid body stimulation has been a interesting and simultaneously controversial subject. In fact, several authors described different responses depending on the animal species used (cat, dog, rabbit, monkey), time of stimulation (short-term v. long-term) and experimental conditions and procedures. According to our experience, the response to carotid body stimulation with cyanide, in normal breathing dogs, consists in hyperpnoea, bradycardia with arterial blood pressure fall (by means of longer diastolic periods), followed by a marked rise in arterial blood pressure and heart rate, after curarization. Concerning the inotropic response to carotid chemoreceptors stimulation, there exists some controversial and even antagonic opinions. In fact, some authors describe a positive inotropic effect, others a negative inotropic effect, and others still defend no inotropic response at all. In the present work, the authors try to contribute to the solution of this problem, studying a group of animals (pig) anaesthetised with chloralose, in which the major modulators of the inotropic response to carotid body stimulation (ventilation; heart rate; and ventricular load conditions) were controlled. To the evaluation of cardiac contractile state, indexes derived from the systolic isovolumic phase were used (maximum left ventricular pressure, dP/dtmax; dP/dtmin) in all the animals. In some animals, other indexes were also used (Vmax, Vpm, (dP/dt)/DP40, Tau and PB). The authors concluded that, in the present experimental conditions, the primary response to carotid body stimulation, in the pig, includes a positive inotropic effect.


Assuntos
Corpo Carotídeo/efeitos dos fármacos , Cianatos/farmacologia , Lobelina/farmacologia , Contração Miocárdica/efeitos dos fármacos , Animais , Masculino , Estimulação Química , Suínos , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia
20.
Pediatria (Säo Paulo) ; 6(4/6): 207-10, 1984.
Artigo em Português | LILACS | ID: lil-22979

RESUMO

Os autores apresentam um caso de doenca de Chagas congenita, diagnosticado aos cinco meses de vida, de maneira casual, quando foi internado por fratura de cranio. Apresentam os achados clinicos-patologicos e justificam a disseminacao intensa e aguda da doenca pela corticoterapia a qual o paciente foi submetido


Assuntos
Lactente , Humanos , Masculino , Corticosteroides , Doença de Chagas
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