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151.
EDTA-induced urothelial cell shedding for the treatment of superficial bladder cancer in the mouse 总被引:3,自引:0,他引:3
OFER NATIV EILATA DALAL GUY HIDAS MOSHE ARONSON 《International journal of urology》2006,13(10):1344-1346
AIM: The aim of this study was to determine the effect of intravesical EDTA instillation on the development of intravesically implanted tumor cells in normal mice. METHODS: The mouse bladder tumor (MBT-2) model was used in female C3H/eb mice to evaluate the amount of normal urothelial cell shedding, and the degree of tumor growth inhibition following intravesical EDTA instillation in comparison with phosphate-buffered saline (PBS) instillation. RESULTS: At 1 h after instillation, the number of urothelial cells aspirated was 500-1000 per PBS-treated mouse and 10,000-20,000 per EDTA-treated mouse (P < 0.00001). The bladder weight, which reflected the effect of the agent on the tumor, was similar in the untreated and PBS-treated mice (105.46 +/- 46 mg and 106.2 +/- 50 mg, respectively). It was significantly lower in the EDTA-treated mice (80.4 +/- 42 mg) (P = 0.0045). CONCLUSIONS: Intravesical administration of EDTA results in significant normal and neoplastic urothelial cell shedding. Intravesical irrigation with EDTA may prevent adherence of the malignant cells to the bladder wall following tumor resection. 相似文献
152.
K. OKAMURA I. KOBAYASHI K. MATSUO T. KIYOSHIMA K. YAMAMOTO A. MIYOSHI & H. SAKAI 《Histopathology》1997,31(6):540-548
Aims:
The purpose of this study is to examine the relationship between immunohistochemical localization of cathepsin D (CD), proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGF-R) in 65 cases of breast carcinoma in Japanese women and traditional prognostic factors such as histological grade, lymph node status, mitotic rate and clinical stage, in order to possibly identify some indicator(s) that may be specifically associated with prognosis.
Methods and results:
Serial sections of 5-μm thick were cut from the archival formalin-fixed, paraffin-embedded tissue blocks, and processed for CD, PCNA and EGF-R immunostaining. The results were analysed by computer-based image analysis system. All samples showed a positive immunoreaction for cathepsin D in both the parenchyma and stroma. However, the staining area and intensity varied from cell to cell in the parenchyma and stroma as well as among samples. Subsequently, the evaluation of immunostaining for CD was separately performed in both the parenchyma and stroma (CDpar and CDstr, respectively) and the combination of both components (CDtotal). PCNA and EGF-R showed positive immunostaining almost exclusively in the parenchymal component of the carcinoma tissue specimens. CDtotal significantly correlated with the histological grade, PCNA index (PI), mitotic rate (MR), EGF-R and lymph node metastasis. Significant correlation was also demonstrated between CDpar and the histological grade, EGF-R and lymph node metastasis, or between CDstr and MR, EGF-R and lymph node metastasis. EGF-R correlated highly with the histological grade, MR score, lymph node metastases and recurrence-free survival.
Conclusions:
Both the CD parameters and EGF-R are valuable indicators for predicting the biological behaviour of human breast carcinoma. 相似文献
153.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination. 相似文献
154.
155.
Jean de Ville de Goyet Raymond Reding Viktoria Hausleithner Jan Lerut Jean-Bernard Otte 《Transplant international》1995,8(4):280-285
This paper describes a quick procedure for cadaveric liver graft retrieval during multiple organ harvesting. The technique is based on minimal preliminary dissection, absence of in situ direct portal perfusion, and en bloc removal of the liver and pancreas, with an aortic patch encompassing the coeliac trunk and superior mesenteric artery. The results of 110 pediatric liver transplantations with 109 organs harvested using this technique are reported. There were no graft harvesting injuries. The liver graft primary nonfunction rate was 4.5% (5/110). The 3-month retransplantation rate was 10%. The actual patient survival rates were 93% at 3 months and 90% at 1 year; actual graft survival rates were 85.5% and 78%, respectively. The technique described was at least as safe as conventional procedures. A major advantage of the procedure is its flexibility, which allows for the easily combined procurement of other organs (whole pancreas and intestine). 相似文献
156.
本文应用核苷掺入技术及电镜观察首次证实雷公藤内酯对人胃癌细胞株 FGC_(85)的杀伤作用。用药早期,细胞数,分裂指数及 DNA,RNA 合成无明显变化,但出现核仁脱粒及核仁破碎等变化;晚期,电镜观察发现细胞以凋落方式死亡,药物主要作用于间期细胞,其杀伤机构的始动环节可能与核酸代谢障碍无关。 相似文献
157.
158.
Hexachlorobenzene (HCB) is still frequently found at elevated levels in human adipose tissue and breast milk. As intoxication
with HCB causes neurological disturbance in human beings, the purpose of the present study was to examine neurobehavioral
functions in rats after pre- and postnatal exposure. Female rats were fed diets with 0, 4, 8, or 16 mg HCB/kg diet. Exposure
started 90 days prior to mating and was continued throughout mating, gestation, and lactation. Thereafter, the offspring were
given the same diets as their respective mothers. HCB levels were determined in the brain, the liver, and in the adipose tissue
from virgin rats, dams, and the offspring. Concentrations on a lipid basis were found to decline in the order adipose>liver>brain.
The exposure levels chosen did not cause gross toxic effects in dams or offspring. There were dose-related increases in liver-to-body-weight
ratios in exposed dams, but not in unmated females treated alike. Behavioral testing was conducted in the offspring. Examination
of open-field activity on PND 21, and of active avoidance learning on PND 90 failed to reveal significant differences between
groups. Training of operant behavior started at the age of 150 days in the offspring from the control, the 8-mg group, and
the 16-mg group. Animals were trained on a fixed interval schedule of 1 min (FI-1). On this schedule, responses were reinforced
by a food pellet every time 1 min had elapsed after the preceding reinforcement. There were dose-dependent reductions in the
post-reinforcement pause, e.g. the time between each reinforcement and the first reaction emitted after it. In addition, the
index of curvature, which describes the efficiency of performance on the FI-1 schedule, was decreased in a dose-dependent
fashion.
Received: 12 April 1994 / Accepted: 26 June 1995 相似文献
159.
Dr. S. Eggstein MD G. Manthey MT T. Hirsch PhD F. Baas MA B. U. V. Specht MD E. H. Farthmann MD 《Digestive diseases and sciences》1996,41(6):1069-1075
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr). 相似文献
160.
Dr. J. Tajti MD PhD ; Dr. K. Sas MD ; Dr. D. Szok MD ; Dr. E. Vörös MD ; Dr. L. Vécsei MD DSc 《Headache》1996,36(4):259-260
We report on a patient with clusterlike headache and multiple brain metastases of lung cancer. Initially, cluster headache was suggested clinically by characteristic symptoms without any focal central nervous system signs. However, magnetic resonance imaging demonstrated multiple brain metastases. It is possible that tumor necrosis factor may have played a role in initiating the clusterlike headache. 相似文献