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1.
Psychopharmacology (Berl) ; 131(3): 220-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9203232

RESUMO

There has been no consensus about the acute effect of cigarette smoking on cerebral blood flow, and the continuous change of flow in four cerebral vessel flow with peripheral flow during different kinds of cigarette smoking has not been reported until now. Our results indicate smoking increases the flow of four cerebral vessels almost at the same time and with the same pattern. Many cerebral vessels began to show increases about 10 s after commencement. In most cases, cerebral blood velocity began to decrease between 10 and 20 s after cessation. Blood flow in peripheral vessels decreases after commencement, which is thought to be the effect of nicotine. The effect of high nicotine cigarettes is greater than that of low nicotine cigarettes. Continuous and simultaneous measurement of cerebral vessels by ultrasonic Doppler is though to be the only way to establish the detailed blood flow changes during smoking.


Assuntos
Circulação Cerebrovascular , Fumar/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Dióxido de Carbono/sangue , Frequência Cardíaca , Humanos , Masculino , Respiração , Volume de Ventilação Pulmonar
2.
Ultrasound Med Biol ; 18(6-7): 637-43, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1413275

RESUMO

We have developed a new technique for simultaneous assessment of the four cervical cerebral arteries. Using a cervical brace with four freely adjustable Doppler probes attached, we studied four healthy young males and observed their cerebral blood flow changes during common carotid compression. The results indicated various reactivity in these subjects. We observed that carotid compression sometimes affects or stops the ipsilateral vertebral flow according to the intensity and location of compression. Also, the flow of the contralateral internal carotid artery (ICA) and vertebral artery (VA) showed remarkable increases greater than those due to ICA obliteration alone. This indicates the possibility that using only one probe during compression may often result in unknown obliteration of the ipsilateral VAs flow and could also produce other incomplete data. Moreover, with our technique, we would be able to assess the cerebral reserve more precisely and clearly in patients with carotid or vertebral occlusive diseases.


Assuntos
Artéria Carótida Primitiva/fisiologia , Artéria Carótida Interna/fisiologia , Circulação Cerebrovascular , Artéria Vertebral/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna/diagnóstico por imagem , Constrição , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassom , Ultrassonografia , Artéria Vertebral/diagnóstico por imagem
4.
Biken J ; 26(4): 133-43, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6204634

RESUMO

On the basis of the antigenic substructure of tetanus neurotoxin, the antitoxin compositions of horse, rabbit and human tetanus antitoxin sera, in terms of their contents of antibodies against four antigenic determinant groups (alpha, beta-1, beta-2 and the "topographic" determinant group gamma) so far known for the toxin were studied by quantitative precipitation reactions using purified toxin, complementary fragments alpha, beta and fragment beta-1 (a subfragment of fragment beta) of the toxin. The antitoxin antibody composition varied slightly depending on the antiserum preparation. In addition, different patterns of antitoxin antibody composition and toxin-neutralizing ability, characteristic of horse, rabbit and man were found: horse antitoxin sera contained all four kinds of antibodies and horse anti-gamma showed low toxin-neutralizing ability, while human antisera lacked anti-alpha and had anti-gamma with high neutralizing activity but contained anti-beta-1 with no detectable neutralizing activity. Rabbit sera showed an intermediate pattern between those of horse and human sera. In all antisera, antibodies against determinants on the isolated fragment beta account for approximately 80-50 percent of the total precipitable antibodies and anti-beta-2 antibody was invariably present. Immunodiffusion analyses showed that the antitoxin compositions of mouse and guinea pig antisera resembled those of human antisera. In mice, fragment beta was almost as efficient as whole toxin toxoid in eliciting a protective immune response on an equal weight basis, whereas fragments beta-1 and alpha were both relatively poor antigens.


Assuntos
Epitopos/imunologia , Antitoxina Tetânica/imunologia , Toxina Tetânica/imunologia , Animais , Especificidade de Anticorpos , Feminino , Cobaias/imunologia , Cavalos/imunologia , Humanos , Soros Imunes/imunologia , Imunodifusão , Técnicas de Imunoadsorção , Camundongos , Camundongos Endogâmicos ICR/imunologia , Coelhos/imunologia , Especificidade da Espécie
5.
Stroke ; 13(3): 381-5, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7080135

RESUMO

Reversed ophthalmic blood flow in the occlusions (33 patients) and stenoses (11 patients) of the internal carotid artery (ICA) was examined using the ultrasonic Doppler technique. The Doppler shift frequencies of the blood flow signal were analyzed to obtain their sound spectrogram. In stenosis of the ICA, "presystolic notch" was more frequently observed and "d/S" value (S, d; maximum blood flow velocity at systolic and diastolic) was smaller than in occlusion. These two characteristics of stenosis distinguish it from occlusion with 89% accuracy although this method is applicable only for the patients with reversed ophthalmic blood flow.


Assuntos
Doenças das Artérias Carótidas/diagnóstico , Artéria Oftálmica , Velocidade do Fluxo Sanguíneo , Artéria Carótida Interna , Angiografia Cerebral , Constrição Patológica , Diagnóstico Diferencial , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Reologia , Sístole , Ultrassonografia
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