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21.
We report an infant with Pfeiffer syndrome (acrocephalosyndactyly type V) and a solid cartilaginous trachea lacking rings. This airway abnormality has been reported in a child with Crouzon syndrome but has not been described in Pfeiffer syndrome.  相似文献   
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目的 观察应用引导管芯做引导,更换经口气管内导管的临床效果。方法 随机选择26例已完成气管内插管的病人,将引导管芯插入气管导管内至隆突水平,并拔出气管导管;将欲更换的气管导管套在引导管芯外,在管芯引导下将气管导管插入气管内,完成换置;结果 全部病例均顺利完成更换导管,换管过程中病人氧合良好,术后未发生与更换导管相关并发症;结论 应用引导管芯更换气管内导管,方法安全,简便易行,可替代传统换管方法。  相似文献   
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We describe a system we developed that enabled simultaneous measurements of either epithelial calcium ion concentration ([Ca2+]i) or sodium ion concentration [Na+]i with the ciliary beat frequency (CBF) in native ciliated epithelia using either Fura-2 (AM) or SBFI (AM) ratiometric fluorescence photon counting along with nonstationary laser light scattering. Studies were performed using native epithelial tissues obtained from ovine tracheae. The dynamic range of the laser light-scattering system was determined by a simulated light beating experiment. The nonstationary CBF was demonstrated by the time-frequency analysis of the raw photon count sequences of backscattered heterodyne photons from cultured and native epithelia. Calibrations of calcium and sodium ion concentrations were performed using the respective Fura-2 and SBFI impermanent salts as well as in native epithelia. The cumulative responses of 10–6, 10–5, and 10–4} M nifedipine on [Ca2+]i together with the CBF as well as the cumulative responses of 10–5, 10–4, and 10–3 M amiloride on [Na+]i together with the CBF were also determined. Nifedipine decreased [Ca2+]i but had no effect on CBF. Amiloride decreased [Na+]i and CBF. Stimulation of CBF corresponded with either an increase of [Na+]i or an increase of [Ca2+]i. Decreases of [Na+]i or substantial decreases of [Ca2+]i were associated with decreases in the CBF. These data demonstrate the utility of this system for investigating the regulatory mechanisms of intracellular ions dynamics and the CBF in native epithelia. © 1998 Biomedical Engineering Society. PAC98: 8780+s, 8722-q, 4262Be  相似文献   
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目的 提高大鼠气管插管的成功率;方法 对比传统闭式法与改良直视法的成功率;结果传统闭式法的成功率为50%,改良直视法的成功率为100%。结论 改良直视法优于传统闭式法,值得推广应用。  相似文献   
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Introduction. We designed an endotracheal (ET) tube with orthogonally spaced ECG cuff electrodes. This ET tube was evaluated in dogs and sheep to determine (1) whether ECGs recorded from our tube were sufficient to make accurate clinical decisions concerning heart rate and rhythm; and (2) whether metallic cuff electrodes in direct contact with the trachea could induce mucosal burn injury during episodes of defibrillation.Methods. Using experimental animals, we obtained ECGs from their tracheae and compared our findings with ECGs obtained from surface and esophageal electrodes. The electrical activity of the heart was modified by increasing the depth of anesthesia, occluding the left coronary artery, and administering beta-adrenergic drugs. Before the dogs were euthanized, they were subjected to episodes of transthoracic and intrathoracic defibrillation at energy levels of 200 to 400 J. A postmortem pathological examination of the trachea was performed to determine the incidence of mucosal burn injury.Results. Tracheal electrocardiography provided valid information on heart-rate monitoring and certain morphology profiles. The R-R, PR, QRS, and QT intervals measured from the trachea had a correlation of 1.0, 0.96, 0.83, and 0.98, respectively, when compared with the same intervals obtained from surface electrodes. Two tracheae subjected to intrathoracic defibrillation at >300 J revealed evidence of minor burn injury. Some localized epithelium loss was displayed in all tracheae; we attributed this to tracheal intubation.Conclusion. Tracheal electrocardiography may be useful in trauma patients who require intubation where injury precludes placement of chest ECG electrodes.  相似文献   
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Awake intubation using the Bullard laryngoscope can be comfortably and easily performed in the adult. Five cases are presented in which tracheal intubation was performed under topical anaesthesia with light intravenous sedation. In each case, topical anaesthesia was performed by insertion of a Guedel oral airway, with lidocaine ointment applied to the inferior and posterior surfaces. In one case, Bullard intubation was successful where direct laryngoscopy and multiple attempts at bronchoscopic intubation by three different operators had failed. We conclude that the Bullard laryngoscope can be easily used in awake patients and may be a useful alternative where other methods for awake intubation have failed.  相似文献   
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用离体豚鼠气管条,探讨侧柏叶乙酸乙酯提取物对气管平滑肌作用。结果表明,侧柏叶乙酸乙酯提取物能抑制乙酰胆碱,氯化钾所致气管平滑肌收缩,而且能使乙酰胆碱收缩气管平没肌的量效曲线右移,并抑制最大效应,其作用为剂量依赖性心肌肥厚提示侧柏叶乙酸乙酯提取物松驰气管平滑肌作用机制可能与影响Ca^2+的跨膜转运有关。  相似文献   
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