Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Angiomatose Bacilar/diagnóstico , Epistaxe/diagnóstico , Doenças Nasais/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Angiomatose Bacilar/tratamento farmacológico , Diagnóstico Diferencial , Eritromicina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Nasais/tratamento farmacológico , Neoplasias Nasais/diagnóstico , RecidivaRESUMO
The pattern of gap-junctional connections between cells in the vestibular neuroepithelium of the posterior semicircular duct of the alligator lizard are described based upon the study of freeze fracture replicas and ultrathin sections with a transmission electron microscope. Both type I and type II hair cells are coupled to adjacent supporting cells by a series of small macular gap junctions located in a ring around the hair cell at the level of the apical circumferential belt of actin filaments. Adjacent supporting cells are extensively interconnected by gap junctions. A few cases of gap junctions between afferent dendrites and supporting cells, and between afferent dendrites and calyceal nerve endings were seen. These morphological observations together with data from other studies in the literature suggest a possible role for supporting cells in altering the micromechanical properties of the hair cell receptor organs during stimulation.
Assuntos
Actinas/metabolismo , Junções Comunicantes/ultraestrutura , Células Ciliadas Auditivas/ultraestrutura , Células Labirínticas de Suporte/ultraestrutura , Vestíbulo do Labirinto/ultraestrutura , Citoesqueleto de Actina/ultraestrutura , Animais , Dendritos/ultraestrutura , Técnica de Fratura por Congelamento , Lagartos , Microscopia Eletrônica , Neurônios Aferentes/ultraestruturaRESUMO
Electromagnetic-field focusing (EFF) is a method of converging induced eddy current onto a pointed tip of a tuned length return circuit in the near field of a resonator, which results in the production of high temperature. Previously reported applications of this method include various devices for local hyperthermia and a precision surgical device. The latter is currently being used in human clinical trials under two investigational device exemptions from the Food and Drug Administration. In the present work, the thermal profile produced in a uniform, tissue-simulating phantom by the hand-held probe of the surgical EFF system is compared with those produced by mono- and bipolar electrocauteries and by a contact Nd:YAG laser. At the equivalent power setting and 2-cm insertion depth, the EFF probe was shown to have a tighter thermal profile than the monopolar electrocautery or the contact Nd:YAG laser. This finding is consistent with earlier histologic evidence that brain cortical tissue cut by the surgical EFF probe had minimal thermal damage in the tissue surrounding the incision.
