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Background: The placement of an endotracheal tube (ETT) may promote laryngeal swelling, which is an important cause of upper airway obstruction after extubation. The authors hypothesized that laryngeal swelling after ETT placement increases laryngeal resistance and tested that hypothesis by comparing postoperative laryngeal patency between patients with ETT placement and those with a Laryngeal Mask Airway(TM) (LMA(TM)).

Methods: Fourteen adult patients who underwent elective minor surgeries were randomly allocated to two groups whose airway would be managed through ETTs (the ETT group) or LMAs(TM) (the LMA(TM) group) during the surgery. While maintaining at sevoflurane 1 minimum alveolar concentration, the authors measured laryngeal resistance before and after surgery, during both spontaneous breathing and mechanical ventilation under complete paralysis. In addition, they endoscopically measured the vocal cord angle under complete paralysis.

Results: In association with marked swelling of the vocal cords, the vocal cord angle significantly decreased after surgery in the ETT group, whereas the angle did not change in the LMA group. Laryngeal resistance during mechanical ventilation significantly increased only in the ETT group. Laryngeal resistance during spontaneous breathing significantly increased after surgeries in both groups.  相似文献   

4.
In order to find the three-dimensional distribution of ventricular depolarization potentials in left anterior hemiblock (LAHB) diagnosed by the conventional scalar ECG, 7 subjects with LAHB aged 9 to 62 years old who were otherwise healthy were studied by computer graphic electrocardiography (CGECG).Two modes of the initial ventricular depolarization (IVD) were noted. (1) The IVD appeared irregularly and separately on the mid- to lower central region of the anterior body surface. (2) The IVD appeared in a form rather like a parallelogram on the central region of the anterior body surface. Both (1) and (2) potentials propagated toward the left middle, lower, and lateral regions of the anterior body surface as normally observed; however, they were far lower in voltage than those observed in intact subjects.From the results, it has been concluded that LAHB may be, not a block, but rather a defective ventricular septal conduction.Presented at the 34th Annual Congress, International College of Angiology, Budapest, Hungary, July 1992.  相似文献   
5.
Summary Forty-nine out of 54 male workers engaged in the production of an epoxy compound, t-methyl-3-phenylglycidate, showed skin symptoms in varing degrees that may be due to the skin-irritative effect of the compound. The exposed workers were also shown to have subjective symptoms which may be related to the irritative property of the compound on surface tissue. Laboratory examinations on the blood obtained from the exposed workers showed significantly higher values of leukocyte concentration as compared with the non-exposed controls. This was chiefly caused by the increase of neutrophilic granulocytes and T-cell lymphocytes. Serum IgA levels of the exposed workers were shown to be significantly lower than those of the control group. Hemoglobin concentration, hematocrit value and red cell count of the exposed workers remained at the same level as those of the control subjects. Liver or kidney damage was not found in biochemical analyses on the sera of exposed workers.  相似文献   
6.
Transmission electron microscopy of thin sections of the rat incisor pulp revealed that in the middle region of the incisor there were fenestrated capillaries in the “predentinal plexus” and that this region contained the tallest odontoblasts. The odontoblasts gradually became shortened in the incisal part of this region: the fenestrated capillaries in the predentinal plexus changed to continuous type capillaries. Almost all the odontoblasts had degenerated near the incisal end of the tooth. The predentinal plexus disappeared in this region, but the “subodontoblastic capillary plexus” persisted. In a specific region just beneath the worn incisal end, numerous macrophages and polymorphonuclear neutrophils appeared and scavenged the degenerating cells, possibly including the odontoblasts. © 1993 Wiley-Liss, Inc.  相似文献   
7.
 We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement ”cohort migration”. Electron and immunoelectron microscopic study of the migrating cell sheets demonstrated localized release from cell–cell adhesion only at the lower portion of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation of the E-cadherin–catenin complex, including β-catenin. Cell–extracellular matrix (ECM) interactions involved in this TPA-induced cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated. L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum, but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin–catenin complex induced by TPA, indicating that cell–cell interactions were adjusted to suit cell migration, irrespective of the condition of cell–ECM adhesion, during TPA-induced cohort migration. Received: 31 December 1997 / Accepted: 2 April 1998  相似文献   
8.
An investigation on the health status of 79 male preparatory school students lodging at a dormitory in Japan was carried out by questionnaire on lifestyles, subjective symptoms and mental status, as compared with two control groups: 73 medical students and 36 new employees. About 83 % of them slept less than 6 hours and 70 % of them did not exercise. Many students are troubled with back pain or lumbago(47%), sensation of incomplete bladder emptying(l6%), loss of visual acuity(55%) and eye fatigue(65%). Self-rating depression scale score of preparatory school students was not significantly higher than those of the control groups. The lifestyles of preparatory school students found to be very restricted and strained. However, no significant differences on mental adverse health effects was found among three groups.  相似文献   
9.
Inducible nitric oxide (NO) synthase (iNOS) is believed to contribute to the pathogenesis of endotoxin-induced uveitis (EIU). In the present study, we investigated the inhibitory effects of N(G)-nitro-L-arginine methyl ester (L-NAME), a non-selective NOS inhibitor, and S,S'-1,4-phenylene-bis(1,2-ethanediyl)bis-isothiourea (PBITU), a potent and selective iNOS inhibitor, on intraocular NO production in EIU rabbits using an in vivo intraocular microdialysis technique. The flare level in the anterior chamber increased from 1h after the injection of 100 micro g/kg lipopolysaccharide (LPS), and continued to increase for 24h. Aqueous humor protein concentrations were significantly increased at 24h after LPS-injection. These changes were significantly reduced by L-NAME (10mg/kg) and PBITU (1mg/kg), but not by D-NAME (10mg/kg). The increase in NO(2)(-) and NO(3)(-) levels in the dialysate induced by LPS was significantly inhibited by L-NAME (10mg/kg) and PBITU (1mg/kg), but not by D-NAME (10mg/kg). These results suggest that activation of iNOS may play a key role in the development of EIU, and selective inhibitors of iNOS may have therapeutic applications in the treatment of EIU.  相似文献   
10.
Myoblast therapy for stress urinary incontinence and bladder dysfunction   总被引:4,自引:1,他引:3  
The field of tissue engineering and gene therapy has an exciting and promising future. During the past few years we have begun a comprehensive effort to investigate the use of myoblasts to improve and expand the treatment of stress urinary incontinence and bladder dysfunction. Moreover, we can expect the application of myoblast-mediated ex vivo gene transfer in the field of urology. In this paper we discuss the compositions of and methods involving the use of myogenic or muscle-derived cells for tissue engineering and cell-mediated gene therapy.  相似文献   
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