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71.
Background: Sevoflurane is an inhalational anesthetic with characteristics suited for use in children. To determine whether the induction, recovery, and safety characteristics of sevoflurane differ from those of halothane, the following open-labeled, multicenter, randomized, controlled, phase III study in children undergoing ambulatory surgery was designed.

Methods: Three hundred seventy-five children, ASA physical status 1 or 2, were randomly assigned in a 2:1 ratio to receive either sevoflurane or halothane, both in 60% N2 O and 40% O2. Anesthesia was induced using a mask with an Ayre's t piece or Bain circuit in four of the centers and a mask with a circle circuit in the fifth center. Maximum inspired concentrations during induction of anesthesia were 7% sevoflurane and 4.3% halothane. Anesthesia was maintained by spontaneous ventilation, without tracheal intubation. End-tidal concentrations of both inhalational anesthetics were adjusted to 1.0 MAC for at least 10 min before the end of surgery. Induction and recovery characteristics and all side effects were recorded. The plasma concentration of inorganic fluoride was measured at induction of and 1 h after anesthesia.

Results: During induction of anesthesia, the time to loss of the eyelash reflex with sevoflurane was 0.3 min faster than with halothane (P < 0.001). The incidence of airway reflex responses was similar, albeit infrequent with both anesthetics. The total MAC *symbol* h exposure to sevoflurane was 11% less than the exposure to halothane (P < 0.013), although the end-tidal MAC multiple during the final 10 min of anesthesia was similar for both groups. Early recovery as evidenced by the time to response to commands after sevoflurane was 33% more rapid than it was after halothane (P < 0.001), although the time to discharge from hospital was similar for both anesthetics. The mean (+/-SD) plasma concentration of inorganic fluoride 1 h after discontinuation of sevoflurane was 10.3+/-3.5 micro Meter. The overall incidence of adverse events attributable to sevoflurane was similar to that of halothane, although the incidence of agitation attributable to sevoflurane was almost threefold greater than that attributable to halothane (P < 0.004).  相似文献   

72.
First branchial cleft fistula is a rare congenital malformation of the head and neck with an incidence of less than 10% of all branchial cleft defects. We herein report a 15-year-old girl who had a cystic mass in the postauricular region with an external opening on the posterior face of the earlobe. Surgical exploration revealed that a second sinus tract was passing through the conchal cartilage without going beyond the skin of the external acoustic meatus. The mass and the tract were excised along with the opening on the earlobe as well as the skin island surrounding the opening. The case was treated surgically with success .The significance of our case was the location of external opening on the earlobe.  相似文献   
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The progress of cognitive visual dysfunction over an 8-year period of a child who sustained bilateral occipital-lobe infarctions at the age of 21/2 years is described. She survived with normal intelligence and went on to attend mainstream school. She manifested many features of cognitive visual impairment and, in particular, developed a form of pure alexia without agraphia. She achieved some letter-by-letter reading but no sight vocabulary development, including to her own name. She learned to write imaginatively employing phonetically true spelling but cannot read what she has written. Her progress and the difficulties encountered during the management of her condition are discussed in this first case report of the evolution of pure alexia without agraphia in childhood. The features of this syndrome in the developing child who has never developed the capacity to read are contrasted with that seen in affected adults.  相似文献   
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This study was designed to assess the accuracy of end-tidalPco 2 and transcutaneousPco 2 as measurements of arterialPco 2 in extubated, spontaneously breathing patients recovering from general anesthesia. In 30 patients, measurement of arterial transcutaneous, and end-tidalPco 2 were taken simultaneously with body temperature approximately every 15 minutes over a 2-hour period. ArterialPco 2 values were corrected for body temperature. Values for Paco 2 were compared with those forPetCO2 and Psco 2 by linear regression analysis and by calculation of bias ± precision. Thirty-six percent of the capnogram tracings obtained did not develop a plateau phase. We found poor correlation between end-tidal and arterialPco 2 regardless of the shape of the capnogram tracing, as well as poor correlation between transcutaneous and arterialPco 2. Although the measurements of bias and precision of noninvasivePco 2 monitors in this population are comparable to studies in other populations, we advise caution in relying on the routine use ofPetCO2 or Psco 2 for the noninvasive assessment of respiratory depression in extubated, spontaneously breathing patients recovering from general anesthesia.  相似文献   
78.
Chronic Allograft Rejection   总被引:3,自引:0,他引:3  
  相似文献   
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Organ-specific injury after transplantation presents with a variety of clinical and pathological phenotypes, yet the factors influencing development of each outcome are poorly understood. Because primed T lymphocytes must re-encounter their antigen within the target organ to engage effector functions, we postulated that the cellular location of antigen within that organ could significantly impact the induced pathology. We challenged female Marilyn CD4 T-cell receptor transgenic mice, in which all T cells are specific for the male minor transplantation antigen, with male heart transplants expressing the relevant peptide: major histocompatibility complex on either graft parenchymal/vascular cells or alternatively, on graft-infiltrating mononuclear cells. The two different graft donors led to equivalent activation of recipient T cells as assessed by frequency, cell surface marker expression, cytokine production, and the ability to traffic to the graft. Nonetheless, if the target antigen was expressed on graft vascular and/or parenchymal cells, the outcome was acute graft destruction. In contrast, if the antigen was expressed only on graft-infiltrating mononuclear cells the same effector T-cell repertoire caused chronic rejection and vasculopathy. This unique result, that target antigen location can influence pathological outcome, has significant implications for understanding the pathogenesis of chronic allograft injury in humans.  相似文献   
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