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51.
Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
  相似文献   
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A microprocessor-based real-time digital vibrotactile vocoder system has been developed to train the deaf and for artificial hearing research. The system is composed of a microcomputer module with a digital signal processor interface units and an attenuator/driver circuit. Live or digitised (stored or synthetic) speech is presented to the skin spectrally through a belt housing eight or 16 vibrators. Speech is processed in real time using a fast Fourier transform. The system is also capable of presenting any arbitrary spatiotemporal pattern on the skin for artificial hearing experiments. A preliminary experiment with a deaf subject indicates that the system is potentially an effective device for artificial hearing.  相似文献   
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Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed.  相似文献   
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BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
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Vascularity for healing of meniscus repairs   总被引:5,自引:0,他引:5  
Vascularity in the human meniscus is poor beyond 1-2 mm from the meniscosynovial junction, yet 22% of the tears in this series occur with a greater than or equal to 3-mm peripheral white rim. It is possible to suture these tears with the wider peripheral white rims, but healing rates are reduced because it is more difficult to obtain a satisfactory vascular supply. This article describes the history of our efforts at obtaining blood supply for healing of meniscus tears with a peripheral white rim up to 5 mm. Resection of the peripheral white rim to the vascular bed was unsatisfactory because it reduced the size of the meniscus and, by 3 years, the subsequent degenerative changes in the knee were comparable to meniscectomy. Holes made in the rim with a biopsy needle were again unsuccessful at improving healing. The present technique involves using rasps to abrade the parameniscal synovium on both the superior and inferior surface of the peripheral white rim. None of the peripheral white rim is resected. In the first series of 240 patients in whom peripheral white rim resection or the biopsy punch was used, the failure rate of meniscus healing was 22%. In a subsequent series of 68 patients (52 males, 16 females) who had 81 meniscal repairs by means of the rasp for parameniscal synovial abrasion, the failure rate was 9%. The rasp appears to be the safest and most effective method to gain vascularity for healing of meniscus repairs. It is possible to obtain healing with 5-mm peripheral white rims without resection of any portion of this rim, thus maintaining the full size of the meniscus.  相似文献   
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An industrial hygiene methodology that was developed in support of an epidemiologic case-control study is described. This study was conducted to investigate a potentially increased incidence of colorectal cancer among employees who worked at a unit that manufactured polypropylene by a heavy diluent process. Retrospective epidemiologic case-control studies typically have exposure assessment problems because industrial hygiene monitoring data are often not available. Misleading job titles are another problem that can provide a poor framework for estimating exposures. In addition, a job title-based exposure assessment assumes individual work patterns are not important in assessing worker exposures, although this is contradictory to industrial hygiene experience. The design of the case-control study provided an innovative industrial hygiene approach to circumvent these typical exposure estimating problems. The industrial hygiene methodology of the case-control study included assessing historical exposures, developing an exposure estimating matrix, selecting candidate etiologic agents based on a joint toxicologic and industrial hygiene review, administering a work activity questionnaire, calculating exposure scores, and conducting a statistical analysis. The study design also provided an additional exposure measurement independent of the toxicologic and industrial hygiene review. This provided an opportunity to compare the likelihood of exposure misclassification and, as expected, showed that a more detailed exposure estimate resulted in less misclassification.  相似文献   
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