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81.
Twenty-one consecutive patients with anal carcinoma of squamous cell type were evaluated by transanorectal ultrasonography (Brüel & Kjaeer) prior to radiation therapy. The normal anal anatomy, with three distinct layers, was easily demonstrated both in vitro and in vivo. The middle, low echogenic layer corresponded above the dentate line to the muscularis propria and more distally to the internal and external sphincters. A hypoechoic area, representing tumour, was detected in all patients. Using the ultrasound findings, it appeared possible to classify the depth of tumour invasion into four levels with respect to whether or not invasion had reached or penetrated beyond the muscular wall or into adjacent organs. Eighteen of 21 tumours had penetrated the muscular wall. In 3 cases low echogenic, rounded structures, interpreted as enlarged lymph nodes, were identified. The ultrasonographic findings were compared with digital staging. Tumour invasion had penetrated the muscular wall in 2 out of 3 stage T1 patients and in 10 out of 11 stage T2 patients. Prospective studies will show whether estimates of tumour size and depth of invasion in relation to various normal structures, as judged by ultrasonography, are of value prognostically and for the choice of therapy.  相似文献   
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Antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement beads have been used as a local drug delivery system for the treatment of bone and soft tissue infections. The beads deliver a high local level of antibiotic with a decreased risk of toxic systemic levels. This study was undertaken to determine the antibiotic release characteristics of tobramycin-impregnated beads over time and to determine the compressive strength of these beads. Acrylic resin (PMMA) bone cement beads were prepared with three different concentrations of tobramycin. The beads were tested for compressive strength, and their antibiotic release characteristics were determined over a 21 day period by radioimmunoassay and by biological testing against a variety of bacteria. The compressive strength of the beads was found to be adequate to avoid fragmentation during their clinical use. There was gradual release of tobramycin from the beads over the entire 21 days, but the release was most marked during the first 48 hours. There was antibiotic activity against both gram-negative and gram-positive organisms, except Enterococcus, for the entire 21 day period. The release of tobramycin followed a curvilinear relationship and was directly related to the initial antibiotic concentration of the bead. Tobramycin-impregnated polymethylmethacrylate beads may represent a reliable method of local antibiotic delivery with sustained activity against a broad spectrum of organisms.  相似文献   
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A digital computer has been applied to the laboratory diagnosis of drug overdose. Analytic data is entered by the technologist at a keyboard in response to computer instructions. Major and minor ultraviolet absorption peaks, pH dependent spectral shifts, and peak absorbance ratios are used for decision making. Data derived from thin-layer chromatography and colorimetric tests are used for drugs without sufficiently strong spectra. The program can be interrupted and re-entered at any point if additional analyses are required. Results are printed out at the terminal after each step. Upon completion of the screen a summary report lists drugs present (with concentration), absent, and not tested. This system has been developed primarily for application in the general hospital laboratory. The drugs or drug groups included in the program comprise well over 90% of those involved in acute overdose.  相似文献   
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Intramedullary nailing of the tibia is a controversial procedure for fractures of the tibial shaft. Experience with 50 fractures (58% acute, 8% pathologic, and 34% unsuccessfully treated previously by other methods) with an average follow-up period of one year proved that tibial Küntscher nailing is effective. Mean time to clinical union, with patients independently ambulatory and resuming all work activity, was 29 weeks. Union was demonstrated radiographically at 13 weeks. The major complications were delayed union (2 patients), nail protrusion at the knee (2 patients), osteitis (1 patient), and thrombophlebitis (1 patient). Antirotation wires were used in addition to a Küntscher nail for fractures with inherent rotational instability. Blocking screws were used for fractures predisposed to bending. Technical problems arose most often at the nail entrance site, in negotiation of Herzog's curve, and in selection of proper nail length and caliber. With experience and technical skill, even highly complex tibial fractures can be successfully treated by this method.  相似文献   
89.
Gentamicin-PMMA beads were placed in maxillofacial wounds of ten dogs, and gentamicin levels from wound drain sites, serum, and urine were measured by radioimmunoassay. The results indicate extremely high wound and modest urine levels (which decrease exponentially) concurrently with negligible serum levels of gentamicin. The results of this study of a highly vascularized area were similar to other studies in which beads were placed in avascular areas.  相似文献   
90.
OBJECTIVE: To investigate the expression and potential clinical usefulness of structure-specific flap endonuclease 1 (FEN-1) in human primary prostate cancer using tissue microarray technology, as FEN-1 was recently identified to be overexpressed in CL1.1, the most aggressive clone generated from the hormone-refractory prostate cancer cell line CL1. MATERIALS AND METHODS: Immunohistochemistry was performed on tissue microarrays constructed from paraffin-embedded specimens of primary prostate cancer from 246 patients who had had a radical prostatectomy. Prostatic intraepithelial neoplasia (PIN), benign prostatic hyperplasia (BPH) and normal prostate epithelium were represented on the array. FEN-1 nuclear expression was scored based on the percentage of target cells staining positively, and correlated with Gleason score, preoperative prostate-specific antigen (PSA) level and pathological stage. The time to PSA recurrence was also analysed. RESULTS: The mean expression of FEN-1 was significantly higher in cancer (36.7%) than in normal (13.2%), BPH (4.5%) and PIN (15.4%) specimens (P < 0.001). FEN-1 expression was significantly correlated with Gleason score (ó = 0.23, P = 0.002). A higher preoperative serum PSA level (P = 0.015), Gleason score > or = 7 (P < 0.001), seminal vesicle invasion (P < 0.001) and capsular involvement (P = 0.004) were associated with PSA recurrence, whereas FEN-1 expression was not. In a multivariate analysis, only Gleason score > or = 7 (P < 0.001), seminal vesicle invasion (P = 0.005) and capsular involvement (P = 0.009) were retained as independent predictors for PSA recurrence. CONCLUSIONS: FEN-1 is overexpressed in prostate cancer compared with matched normal prostate, and its expression increases with tumour dedifferentiation, as shown by increasing Gleason score. These results suggest that FEN-1 might be a potential marker for selecting patients at high risk, and a potential target for prostate cancer diagnosis and therapy.  相似文献   
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