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31.
The aim of this study was to assess the accuracy of technetium 99m-labeled red cell scintigraphy in localizing the site of lower gastrointestinal bleeding. The outcome of 203 patients undergoing technetium 99m-labeled red cell scintigraphy was reviewed, and the scan result was compared with the true site of bleeding. The true site of bleeding was determined by other methods including angiography and surgical pathology. Fifty-two scans (26%) were positive and indicated a specific site of bleeding. A definitive bleeding site was identified in 22 patients by other means and correlated with the technetium scan in only 9 cases. The nuclear scan was incorrect in the remaining 13 cases, implying a localization error of 25% (13 of 52). A subgroup of 19 patients with a positive scan underwent a surgical procedure directed by the nuclear scan. Eight of these 12 patients had incorrect surgical procedures based upon findings of more definitive tests, indicating a surgical error of 42% (8 of 19). We conclude that the technetium 99m-labeled red cell scan's ability to accurately localize the site of lower gastrointestinal bleeding is limited. Furthermore, performing a surgical procedure that relies exclusively on localization by red cell scintigraphy will produce an undesirable result in at least 42% of patients.  相似文献   
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The ureteral access set was used 43 times during an 18-month period between 1984 and 1985. Stones lodged throughout the ureter and in the renal pelvis were extracted with a success rate of 51 per cent. Of the upper tract strictures 92 per cent were dilated successfully. Filling defects were diagnosed in 88 per cent of the cases. Foreign bodies were retrieved, Double-J stents were placed and biopsies were successful in each case. Ureteral perforation in 28 per cent of the cases was caused by the dilator in 8 of 12 (19 per cent over-all). The technique and short-term results are discussed. Long-term followup data are not yet available.  相似文献   
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P-glycoprotein expression was demonstrated in two human intestinal adenocarcinoma cell-lines (HCT-8, ileocaecal and T84, colonic) by immunoprecipitation of a 170-180 kDa protein with monoclonal antibody JSB-1. Both HCT-8 and T84 formed functional epithelial cell layers of high transepithelial electrical resistance (greater than 700 omega.cm2) when grown on permeable matrices. These epithelial layers demonstrated vectorial secretion (net vinblastine fluxes in the basal-to-apical direction of 0.135 and 0.452 pmol h-1 cm-2 in HCT-8 and T84 cell layers, respectively, from bathing solutions containing 10 nM vinblastine). These vectorial vinblastine secretions were sensitive to inhibition by verapamil. Passive transepithelial vinblastine permeation was limited by the presence of intercellular (tight) junctions, as demonstrated by the high transepithelial electrical resistance, and verapamil increased this passive vinblastine permeation concomitant with a reduction in the electrical resistance. Cellular vinblastine loading was significantly greater from the basal side, and this was also susceptible to inhibition by basal verapamil. The demonstration of vectorial transport of vinblastine in human intestinal colonic adenocarcinoma cell layers is direct evidence in favour of the hypothesis that the function of mdr1 in epithelial from the gastrointestinal tract is to promote detoxification by a process of epithelial secretion. This study also highlights that cellular vinblastine accumulation depends not only upon P-glycoprotein function, but also upon differential apparent membrane permeabilities and the presence of intercellular (tight) junctions that may restrict drug permeation and cellular accumulation to apical or basal membrane domains.  相似文献   
35.
Because of the complexity and variability in the expression of otitis media, its effects on auditory function are diverse. The various influences of otitis media on auditory function are described within this article, including acoustic reflex, audiometry, and tympanometry.  相似文献   
36.
Our objective was to determine the extent to which lower urinary tract symptoms affect the general health status of men and contribute to the decision to undergo surgery. A cross-sectional population survey using postal questionnaires was conducted in the North West Thames health region, followed by a prospective cohort study of men undergoing prostatectomy (North West Thames and Oxford regions). The subjects in the first survey were 221 men aged 55 and over with previously reported mild, moderate or severe urinary symptoms; subjects in the second study were 388 men undergoing prostatectomy. Main outcome measures were selfreported symptom severity, bothersomeness and general health status (Nottingham Health Profilie, Part 1). The response rate among eligible responders in the population survey was 85.7%. Increasing symptom severity was associated with worsening NHP scores for energy, emotional reactions, sleep and physical mobility (p<0.01). Increasing bother-someness of symptoms was associated with emotional reactions, sleep and pain (p<0.05). Men undergoing surgery reported worse health status than men in the population with the same severity of symptoms as regards emotional reactions, energy and pain. For a given level of symptom severity, the impact of those symptoms on aspects of a man's general health status may be the determinant of seeking and undergoing surgery. Greater understanding of the factors that affect a man's response to his symptoms is needed in interpreting the decision to seek and accept treatment.  相似文献   
37.
In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
38.
High-grade dysplasia was found to extend to an area of pseudoinvasion in the submucosa of a colonic adenoma mimicking invasive carcinoma. The presence of both benign and cytologically malignant epithelium and residual foci of lamina propria among the submucosal glands distinguishes this entity from adenocarcinoma arising in an adenomatous polyp.  相似文献   
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