RESUMO
In this paper, we report the development of a novel technique in which the magnetoresistance of nanostructures is perturbatively measured by transversally modulating the DC magnetic field. It measures the electrical transport counterpart of the transverse magnetic AC-susceptibility. The technique was developed in a conventional four-probe configuration in which a small DC current flows through the sample and a small transverse AC-field perturbates the equilibrium position of the sample magnetization. Lock-in detection, in-phase with the AC-perturbation, is used to measure the voltage signal between the two inner electrodes of the four-probe station. We successfully demonstrated that this signal is proportional to the product of the first derivative of sample resistance with respect to the equilibrium position of the magnetization times the second derivative of the energy with respect to the equilibrium position of the magnetization. These dependences add new features to the technique investigated here that were not captured by the investigations previously reported on the same subject. To show the effective use of the technique, we discuss its application in measuring magnetic properties of thin magnetic films in the non-saturated regime.
RESUMO
Cryptococcal granuloma or toruloma of the central nervous system is very rare, meningoencefalitis or meningitis being most common. The authors present the case of an immunocompetent male patient of 56 years old with initial clinical symptoms of intracranial hypertension due to an occípito-parietal crytococcal granuloma that was removed surgically. The patients was treated post operatively with anphotericin-B and 5-fluorcytosine. Pathophysiology, neuroimaging, diagnosis and treatment of this rare entity are discussed.
Assuntos
Granuloma/microbiologia , Meningite Criptocócica/complicações , Granuloma/diagnóstico , Granuloma/terapia , Humanos , Masculino , Meningite Criptocócica/diagnóstico , Meningite Criptocócica/terapia , Pessoa de Meia-IdadeAssuntos
Aminoglicosídeos/farmacologia , Bactérias/isolamento & purificação , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana , Resistência às Penicilinas/fisiologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , PortugalAssuntos
Tétano/mortalidade , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Tétano/prevenção & controleRESUMO
During the last decade the number of poisonings by pesticides in Portugal has been steadily rising. Out of 140 patients treated in our Intensive Care Unit (I.C.U.), 86 were male and 54 were female, one of whom was 5 months pregnant. Besides all the care and surveillance required by every case of acute poisoning, pregnant females raise particular problems. Four months later, she gave birth to a normal child. Its follow-up has shown a normal morpho-physiological and psycho-motor development.