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1.
Neumol. pediátr. (En línea) ; 16(1): 5-10, 2021. ilus
Artigo em Português | LILACS | ID: biblio-1284148

RESUMO

Asthma is considered the most prevalent chronic disease in children. The pulmonary function measurements are important in the evaluation of the disease, being able to confirm the diagnosis by demonstrating the reversibility of the obstruction as well as detecting risks of poor prognosis in the control of asthma. However, the most common methods for analyzing pulmonary function in this age group have restrictions on its applicability, especially due to the need for cooperation on the part of patients. The forced oscillation technique (FOT) is considered a modern tool capable of estimating measures of respiratory mechanics related to the lungs. This method is easily applicable due to the low need for patient cooperation, an important element in the assessment of children. The aim of this study is to review the clinical utility of the Forced Oscillation Technique in the pulmonary assessment of asthmatic children. The bibliographic search covered the years between 1950 and 2019, in the databases: Medical Literature Analysis and Retrieval System Online (MEDLINE) and Latin American and Caribbean Literature in Health Sciences (LILACS). It was used as a search strategy the combination of the following Medical Subject Headings (MeSH) terms: "asthma", "oscillometry" and "child" crossed through the AND and OR Boolean connectors. In asthmatic children, FOT showed greater accuracy in the evaluation of smaller caliber peripheral airways, which can be applied as a complementary method to spirometry to strengthen the diagnosis, enabling a better understanding of the disease and its progression.


A asma é considerada a doença crônica de maior incidência em crianças. As medidas de função pulmonar são importantes na avaliação da doença, podendo confirmar o diagnóstico pela demonstração de reversibilidade da obstrução assim como detectar riscos de mau prognóstico no controle da asma. Entretanto, os métodos mais usuais para análise da função pulmonar nesta faixa etária apresentam restrições em sua aplicabilidade, especialmente pela necessidade de cooperação por parte dos pacientes. A técnica de oscilações forçadas (FOT) é considerada uma ferramenta moderna capaz de estimar medidas da mecânica respiratória relativas aos pulmões. Este método apresenta fácil aplicabilidade pela baixa necessidade de cooperação do paciente, elemento importante na avaliação de crianças. O objetivo deste estudo é revisar a utilidade clínica da Técnica de Oscilações Forçadas na avaliação pulmonar de crianças asmáticas. A busca bibliográfica contemplou os anos entre 1950 e 2019, nas bases de dados: Medical Literature Analysis and Retrieval System Online (MEDLINE) e Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS). Foi utilizada como estratégia de busca a combinação dos seguintes Medical Subject Headings(MeSH) terms: "asthma", "oscillometry" e "child" cruzados por meio dos conectores booleanos AND e OR. Em crianças asmáticas, a FOT mostrou maior acurácia na avaliação de vias aéreas periféricas de menor calibre, podendo ser aplicada como método complementar a espirometria para encorpar o diagnóstico, possibilitando compreender melhor a doença e sua progressão.


Assuntos
Humanos , Criança , Oscilometria/métodos , Testes de Função Respiratória/métodos , Asma/diagnóstico , Asma/fisiopatologia , Espirometria , Mecânica Respiratória
2.
Phys Rev Lett ; 125(16): 160601, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33124846

RESUMO

Symmetry-breaking dynamical phase transitions (DPTs) abound in the fluctuations of nonequilibrium systems. Here, we show that the spectral features of a particular class of DPTs exhibit the fingerprints of the recently discovered time-crystal phase of matter. Using Doob's transform as a tool, we provide a mechanism to build classical time-crystal generators from the rare event statistics of some driven diffusive systems. An analysis of the Doob's smart field in terms of the order parameter of the transition then leads to the time-crystal lattice gas (TCLG), a model of driven fluid subject to an external packing field, which presents a clear-cut steady-state phase transition to a time-crystalline phase characterized by a matter density wave, which breaks continuous time-translation symmetry and displays rigidity and long-range spatiotemporal order, as required for a time crystal. A hydrodynamic analysis of the TCLG transition uncovers striking similarities, but also key differences, with the Kuramoto synchronization transition. Possible experimental realizations of the TCLG in colloidal fluids are also discussed.

3.
Phys Rev Lett ; 122(1): 015701, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012672

RESUMO

We establish a link between metastability and a discrete time-crystalline phase in a periodically driven open quantum system. The mechanism we highlight requires neither the system to display any microscopic symmetry nor the presence of disorder, but relies instead on the emergence of a metastable regime. We investigate this in detail in an open quantum spin system, which is a canonical model for the exploration of collective phenomena in strongly interacting dissipative Rydberg gases. Here, a semiclassical approach reveals the emergence of a robust discrete time-crystalline phase in the thermodynamic limit in which metastability, dissipation, and interparticle interactions play a crucial role. We perform numerical simulations in order to investigate the dependence on the range of interactions, from all to all to short ranged, and the scaling with system size of the lifetime of the time crystal.

4.
Phys Rev E ; 100(6-1): 060105, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31962402

RESUMO

We describe a general and simple paradigm for discrete time crystals (DTCs), systems with a stable subharmonic response to an external driving field, in a classical thermal setting. We consider, specifically, an Ising model in two dimensions, as a prototypical system with a phase transition into stable phases distinguished by a local order parameter, driven by thermal dynamics and periodically kicked with a noisy protocol. By means of extensive numerical simulations for large sizes-allowed by the classical nature of our model-we show that the system features a true disorder-DTC order phase transition as a function of the noise strength, with a robust DTC phase extending over a wide parameter range. We demonstrate that, when the dynamics is observed stroboscopically, the phase transition to the DTC state appears to be in the equilibrium two-dimensional Ising universality class. However, we explicitly show that the DTC is a genuine nonequilibrium state. More generally, we speculate that systems with thermal phase transitions to multiple competing phases can give rise to DTCs when appropriately driven.

5.
Eur J Gynaecol Oncol ; 14(3): 228-33, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8508880

RESUMO

Forty-seven women affected by Stage Ic-IV epithelial carcinoma of the ovary were treated with the combination of cisplatin, adriamycin (40-50 mg/m2 day 1), and cyclophosphamide (800 mg/m2 day 1) (CAP). Two different schedules of cisplatin were used: 20 mg/m2 day 1-->5 (CAP 5), or 80 mg/m2 on day 1 (CAP 1). In the group of patients with measurable disease the overall response rate was 52%, with a 19% complete response rate. The mean disease-free survival of patients without measurable disease was 24.0+ months. The mean survival of the whole group was 29.2+ months. The mean survival of patients with measurable disease and those without measurable disease was 21.7+ and 35.0+ months respectively. The schedule of cisplatin employed did not influence disease-free survival since the difference between the CAP 1 (21+ months) and the CAP 5 (25+ months) groups was not statistically significant. However the CAP 5 schedule seemed to be better tolerated since it of allowed the delivery be 99% of the planned dose of CDDP, while in the CAP 1 group the dose of CDDP given was only 74% of that planned.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Carcinoma/mortalidade , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Taxa de Sobrevida
6.
Boll Soc Ital Biol Sper ; 65(3): 227-33, 1989 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-2765245

RESUMO

The aim of this research is to study the effects of a diet almost devoid of tryptophan, which is given by a feeding with precooked yellow corn meal (corn mush), on the alterations of the estrous cycle of animals in several conditions of environmental lighting. Indeed, it is known that cerebral serotonin influences the releasing of LH and consequently the ovulation. The different types of environmental lighting are: 1) Natural (alternating Day-Night = L/D). 2) Continuous dark (D/D). 3) Continuous light by sodium steams (L/L sodium). 4) Continuous light by fluorescent neon tubes (L/L neon). The muricide behaviour is studied by comparison rat-mouse. The feeding with precooked yellow corn meal (diet lacking of tryptophan) unchains in the 100% of the observations the CEA (Constant Estrous Anovulatory), and significantly shrinks the estral cycle in the female Wistar Rat in several conditions of environmental lighting.


Assuntos
Dieta , Estro/fisiologia , Farinha , Iluminação , Animais , Ritmo Circadiano , Feminino , Ratos , Ratos Endogâmicos , Fatores de Tempo , Zea mays
12.
Boll Ist Sieroter Milan ; 55(6): 568-72, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-1023893

RESUMO

Mycoplasmas were isolated from 96 of 143 vaginal swabs of pregnant women on their first visit at the Prenatal Center. Ureaplasmas alone were isolated in a higher percentage than M. hominis alone or combination with Ureaplasmas. The isolated cultures at 36 weeks of gestation show no significant difference with the first visit isolation. Colonization of mycoplasmas were found in a higher percentage (93.3%) in the abnormal deliveries than in normal ones. Mycoplasmas were isolated also from throat swabs of 19 out of 141 newborn infants: the proportion of mycoplasmas positive infants was higher in low birth, weight children.


Assuntos
Doenças do Recém-Nascido/microbiologia , Infecções por Mycoplasma/microbiologia , Mycoplasma/isolamento & purificação , Complicações Infecciosas na Gravidez/microbiologia , Peso ao Nascer , Cesárea , Meios de Cultura , Feminino , Doenças Fetais/etiologia , Humanos , Recém-Nascido , Infecções por Mycoplasma/complicações , Complicações do Trabalho de Parto , Gravidez , Cuidado Pré-Natal
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