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排序方式: 共有946条查询结果,搜索用时 15 毫秒
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42.
Uterine leiomyomas in the infertile patient: preoperative localization with MR imaging versus US and hysterosalpingography 总被引:2,自引:0,他引:2
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas. 相似文献
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44.
Purpose. To evaluate different in-vitro cell culture models for their suitability to study drug transport through cell monolayers.
Methods. Bovine turbinate cells (BT; ATCC CRL 1390), human nasal septum tumor cells (RPMI, 2650; ATCC CCL 30), and primary cell cultures of human nasal epithelium were characterized morphologically and histochemically by their lectin binding properties. The development of tight junctions in culture was monitored by actin staining and transepithelial electrical resistance measurements.
Results. The binding pattern of thin-sections of excised human nasal respiratory epithelium was characterized using a pannel of fluorescently-labelled lectins. Mucus in goblet cells was stained by PNA, WGA and SBA, demonstrating the presence of terminal N-acetylglucosamine, N-acetylgalactosamine and galactose residues respectively in the mucus of human nasal cells. Ciliated cells revealed binding sites for N-acetylglucosamine, stained by WGA, whereas Con A, characteristic for mannose moieties, labelled the apical cytoplasm of epithelial cells. Binding sites for DBA were not present in this tissue. Comparing three different cell culture models: BT, RPMI 2650, and human nasal cells in primary culture using three lectins (PNA, WGA, Con A) as well as intracellular actin staining and transepithelial electrical resistance measurements we found, that only human nasal epithelial cells in primary culture showed differentiated epithelial cells, ciliated nasal cells and mucus producing goblet cells, which developed confluent cell monolayers with tight junctions.
Conclusions. Of the in-vitro cell culture models studied, only human nasal cells in primary culture appears to be suitable for drug transport studies. 相似文献
45.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
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A modern and optimal follow-up treatment of patients with uterine cancer requires a detailed knowledge of this disease and its sequelae. Incidence and localisation of cervical and endometrial cancers as well as kind and incidence of therapeutical side effects are demonstrated in the cases of the Gynecological University Hospital of Freiburg, GFR. A study of the psychosexual situation 2--4 years after therapy of uterine cancer is reported. Actual state of social assurances for cancer patients in the German Federal Republic is pointed out. The dates allow to draw conclusions for the follow-up of individual cases. 相似文献
48.
Kissel JC Curl CL Kedan G Lu C Griffith W Barr DB Needham LL Fenske RA 《Journal of exposure analysis and environmental epidemiology》2005,15(2):164-171
A total organophosphorus pesticide exposure study was conducted in Washington State in 1998 in a sample population of 13 children aged 2.5-5.5 years. The children were roughly split between rural and suburban populations and had been previously identified as having potentially elevated organophosphorus pesticide exposures. One component of the study was urine collection and analysis. Urine samples were collected from each subject up to four times in 24 h in two different seasons. Samples were collected at specific time points: before bed, first morning void, after lunch, and before dinner. Urine samples were analyzed initially for the six nonspecific dialkylphosphate (DAP) metabolites and subsequently for eight specific metabolites including malathion dicarboxylic acid (MDA), 3,5,6-trichloro-2-pyridinol (TCPy), and paranitrophenol (PNP). Relatively large percentages of the urine samples contained quantifiable amounts of two of the nonspecific DAP metabolites (DMTP-97%; DETP-67%), and three of the specific metabolites (MDA (71%), TCPy (79%), and PNP (96%)). A percent deviation analysis was employed to determine which of the spot sample time points was the best predictor of the estimated volume-weighted daily average. Of the four spot samples collected, first morning void samples were consistently found to be the best predictors of weighted-average daily metabolite concentration. This finding also held when the data were creatinine-adjusted. The results of this analysis suggest that if spot sampling is to be conducted as part of a biological monitoring study, first morning void samples should be preferentially collected. 相似文献
49.
Patient dosage in computed tomography 总被引:1,自引:0,他引:1
50.