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An experimental model using human fallopian tubes in organ culture was used to study the localization of purified gonococcal lipopolysaccharide (LPS). LPS was visualized by light microscopy with immunoperoxidase staining. Immediately after addition to fallopian tube organ cultures, gonococcal LPS aggregated on the tips of cilia. By 1 to 2 h after exposure, LPS could be seen distributed throughout the cytoplasm of ciliated and nonciliated cells in structures resembling vesicles. By 12 h, there were sloughed, ciliated cells present in the fallopian tube lumen, which had positive LPS stain on their surfaces as well as in their cytoplasm. By 24 h, LPS was distributed throughout the cytoplasm. Control experiments with rabbit oviduct organ cultures showed that LPS failed to attach, enter, or damage mucosal cells. These studies illustrate the initial localization of LPS on human mucosal cells and its uptake into the cells, which are coincident with toxicity for ciliated epithelial cells.  相似文献   
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Postoperative infection after hip joint replacement is an uncommon but potentially devastating complication in contemporary orthopaedics. Management in two stages is the more favored approach in North America. This introduces difficulty with patient management in the interval between stages, delays rehabilitation, and introduces technical difficulty during the second stage. A method has been developed whereby a temporary antibiotic-loaded facsimile of the hip is introduced at the first stage, designed to maintain stability of the joint, length of the limb, and mobility of the patient. It has been used in a total of 86 cases to date. The results in 46 cases with a minimum follow-up of 2 years are reviewed in this article. The infection was controlled in 93.5% of cases.  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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The ability to discriminate perfect from imperfect mirror symmetry was examined at the fovea and at eccentricities out to 10 degrees in the nasal visual field. A 2-AFC method of constant stimuli was employed in which a bilaterally symmetric pattern was presented in one interval and a degraded version of this symmetric pattern in the other. The subject's task was to decide which interval contained the perfectly symmetric pattern. Pattern size was varied by changing the viewing distance. Probit analysis revealed the degree of asymmetry corresponding to 75% correct performance. Given sufficient size scaling, perfectly symmetric stimuli can be discriminated from degraded symmetric stimuli in extra-foveal vision. Spatial scaling with an E2 value similar to that for positional acuity was successful in removing the eccentricity dependence for the task.  相似文献   
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Hydrocephalus in the H-Tx rat: a monogenic disease?   总被引:2,自引:0,他引:2  
The H-Tx rat is a genetic model of hydrocephalus for which thereis a poor understanding of the mode of inheritance.Previous studies suggested a polygenicmode of inheritance but the breeding data to supportthis hypothesis have not been reported. In an attempt to clarify the hereditary mode we have analyzed the data from eight generations of H-Tx rats and four generations of cross-matings between H-Tx rats and Sprague-Dawley (SD) rats. In the H-Tx rat colony 113 of 129 random brother-sister matings (87.60%) produced hydrocephalic offspring, with males and females being equally affected. The overall incidence varied greatly with an average of 30. 35%. In matings with more than three litters, all mating pairs yielded hydrocephalic pups. In cross-matings both hydrocephalic and normal H-Tx rats were mated with normal SD rats. No hydrocephalus was observed in the first generation of 124 pups (F1). Subsequent brother-sister matings of F1 animals generated hydrocephalic pups in the F2 generation with a lower incidence (4.67% in hydrocephalic HTx/SD matings and 5.11% in normal HTx/SD matings, respectively) than in the H-Tx rat colony (30.35%). Back-cross-matings between F2 rats and normal H-Tx rats yielded an incidence of hydrocephalus higher than that of the cross-matings but lower than that of the H-Tx colony. These data strongly suggest that the H-Tx rat is a homozygous carrier of an autosomal recessive hydrocephalus gene with incomplete penetrance. Furthermore, the data clearly rule out sex-linked and polygenic modes of inheritance and provide further insight with respect to genetic inheritance of hydrocephalus.  相似文献   
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