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Bladder tumors develop after the diagnosis of upper urinary tract carcinoma in approximately 20% of cases, whereas the incidence of upper urinary tract tumor after the diagnosis of bladder cancer is low, approximately 2%. In a 64-year-old man who had undergone cystoprostatectomy treatment of bladder carcinoma 6 years previously, with the sigmoid conduit used for supravesicle diversion, a transitional cell carcinoma that developed in the conduit was not revealed with intravenous pyelography at regular follow-up intervals. The patient had only hematuria. After an obstructed left kidney, left ureteral stricture, and a filling defect in the conduit were observed radiologically and biopsy revealed a transitional cell carcinoma at the ureterosigmoid junction, the patient underwent left nephroureterectomy, partial resection of a third of the sigmoid conduit, and right ureteral reimplantation. The occurrence of upper urinary tract carcinoma after treatment of bladder cancer should be considered even in light of intravenous pyelography that shows no abnormality; and when such carcinomas occur in this situation, disease involving the conduit should be ruled out.  相似文献   
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The architecture of normal colonic mucosa suggest that terminally differentiated epithelial cells near the top of the crypt are extruded into the colonic lumen. Morphological studies have identified apoptotic cells among the differentiated phenotypes near the crypt-lumen interface, suggesting a link between pathways of differentiation, apoptosis, and cellular shedding. We studied these processes in HT29 and SW620 cells and found that compared to adherent cells, those cells which were shed during standard, uninduced culture conditions exhibited nonrandom DNA fragmentation characteristic of apoptosis. Moreover, these apoptotic cells, which accumulate in the media, exhibited a more differentiated phenotype. Because short-chain fatty acids (SCFAs) are natural effectors of colonic cell differentiation in vivo, we investigated the specificity of three 4-carbon atom SCFAs on potentiating differentiation and apoptosis, and thus accumulation of shed cells in the conditioned media, in these colonic carcinoma cell lines. Whereas the unbranched SCFA butyrate induced a more differentiated phenotype and enhanced apoptosis, two derivatives of butyrate, branched isobutyric acid and a nonmetabolizable fluorine-substituted analogue, heptafluorobutyric acid, were ineffective in inducing either differentiation or apoptosis. Thus, potentiated differentiation and apoptosis in colonic carcinoma cells were linked to SCFA structure and, most likely, utilization.  相似文献   
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R Mann  EK Yeong  ML Moore  LH Engrav 《Canadian Metallurgical Quarterly》1997,18(2):160-3; discussion 159
This article introduces a new tool to measure the pressure that is under pressure garments. The Iscan (Tekscan, Inc.) system uses a patented ultra-thin (0.007 inch) sensor with multiple sensing locations that sample continuously at 100 times per second. It is noninvasive, convenient, and quick. The study had two parts. First, we established the validity and reliability of the device. Next, garment/scar interface pressures were measured on new garments with use of the Iscan system. Four garment types were studied, with 10 measurements made in each group: Isotoner gloves (Smith & Nephew Roylan, Inc.); custom-fit pressure gloves; Tubigrip forearm sleeves (Seton Health Care Group); and custom-fit pressure forearm sleeves. Mean garment/scar interface pressures were 18 +/- 2 mm Hg for the Isotoner glove, 34 +/- 5 mm Hg for the custom-fit pressure glove, 20 +/- 7 mm Hg for the Tubigrip sleeve, and 35 +/- 6 mm Hg for the custom-fit sleeve. We concluded that the Iscan system can be used to measure pressure under pressure garments accurately and reliably, and that custom-fit hand and forearm garments provide more pressure than Isotoner gloves or Tubigrip sleeves.  相似文献   
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The purpose of this study was to evaluate the relationship between the number of yolk sacs and amnionicity in monochorionic twin pregnancies scanned early in the first trimester. We retrospectively reviewed images of all monochorionic twins scanned between 6 and 9.5 weeks' gestation and with pathologic or sonographic confirmation of chorionicity-amnionicity. Each film was reviewed for the number of yolk sacs present, as well as for the gestational age at which the amniotic membrane was first visualized. Twenty monochorionic-diamniotic pregnancies and two monochorionic-monoamniotic pregnancies met the criteria for inclusion in the study. In diamniotic pregnancies scanned at less than 8 weeks' gestation, only the yolk sacs were identified; none of the dividing amniotic membranes were detected. Two yolk sacs were identified in all but one case. In this case, although one yolk sac was seen at 6 weeks, follow-up scanning at 8 weeks revealed two yolk sacs. In each of the monochorionic-monoamniotic twin pregnancies, one yolk sac was seen at 9 weeks and a single amnion encircled both embryos. We conclude that the sonographic identification of two yolk scas in monochorionic twins enables us to make the diagnosis of diamniotic twins early in the first trimester, before the amniotic membrane can be imaged. The presence of one yolk sac should prompt a follow-up ultrasonogram to assign amnionicity definitively.  相似文献   
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Bacterial collagenase was used to study the susceptibility of dermal sheep collagen (DSC) cross-linked with a mixture of the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide hydrochloride and N-hydroxysuccinimide (E/N-DSC) towards enzymatic degradation. Contrary to non-cross-linked DSC (N-DSC), which had a rate of weight-loss of 18.1% per hour upon degradation, no weight loss was observed for E/N-DSC during a 24 h degradation period. The tensile strength of the E/N-DSC samples decreased during this time period, resulting in partially degraded samples having 80% of the initial tensile strength remaining. The susceptibility of E/N-DSC samples towards enzymatic degradation could be controlled by varying the degree of cross-linking of the samples. Ethylene oxide sterilization of E/N-DSC samples made the material more resistant against degradation compared with non-sterilized E/N-DSC samples. This may be explained by a decrease of the adsorption of bacterial collagenase onto the collagen owing to reaction of ethylene oxide with remaining free amine groups in the collagen matrix.  相似文献   
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