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The authors describe a very rare case of choreoathetotic movements which appeared in an epileptic in strict relationship to a toxic concentration of diphenylhydantoin in the serum. These movements were reversible and disappeared after reduction of drug dose and its serum concentration falling to the therapeutic range. 相似文献
3.
We report the results of a histologic evaluation of muscle (muscularis mucosa) in the lamina propria of the urinary bladder performed on 100 consecutive cystectomy specimens. Muscle fibers were found in the lamina propria lying parallel to the mucosa and forming a distinct muscularis mucosa in three cases; they were interrupted or discontinuous in 20 cases, and dispersed or scattered, forming thin bundles, in 71 cases. In six cases, there were no muscle fibers in the lamina propria. In addition, we noticed that the lamina propria contains large vessels that run along the length of the lamina propria in a continuous or interrupted fashion. When muscle fibers are present, they are associated with these vessels. Since prognosis and management of muscle invasive carcinomas (stage B) is different from that of lamina propria-invasive tumors (stage A), pathologists and urologists should be aware of the presence of a muscularis mucosa in the urinary bladder. 相似文献
4.
Martina Plísková Jan Vondrácek Borivoj Vojtesek Alois Kozubík Miroslav Machala 《Toxicological sciences》2005,83(2):246-256
Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BaP), are carcinogens suggested to be involved in development of human cancer. Several recent studies have reported that PAHs can activate estrogen receptors (ER), either directly or indirectly by producing estrogenic metabolites. We hypothesized that the activation of ER by PAHs or their metabolites could induce cell proliferation in estrogen-sensitive cells. In the present study, we found that two PAHs, benz[a]anthracene (BaA) and BaP, can stimulate proliferation of human breast carcinoma MCF-7 cells at concentrations 100 nM and higher. This effect was ER-dependent, because it was blocked by the pure antiestrogen ICI 182,780. Although both PAHs partially inhibited S-phase entry and DNA synthesis induced by 17beta-estradiol, they stimulated S-phase entry when applied to MCF-7 cells synchronized by serum deprivation. This was in contrast with model antiestrogenic aryl hydrocarbon receptor ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin, which fully suppressed S-phase entry. BaP, which is a strong mutagen, was found to induce p53 tumor suppressor expression, a partial S-phase arrest and at higher concentrations also cell death. Pifithrin-alpha, a synthetic inhibitor of p53 activity, abolished both S-phase arrest and apoptosis induced by genotoxic PAHs, and it potentiated the proliferative effect of BaP. Thus, both genotoxic and nongenotoxic events seem to interact in the effects of BaP on cell proliferation. Taken together, our data indicate that both BaA and BaP can stimulate cell proliferation through activation of ER. The proliferative effects of these carcinogenic compounds might contribute to tumor promotion in estrogen-sensitive tissues. 相似文献
5.
Altered expression of retinoblastoma protein and known prognostic variables in locally advanced bladder cancer. 总被引:11,自引:0,他引:11
C J Logothetis H J Xu J Y Ro S X Hu A Sahin N Ordonez W F Benedict 《Journal of the National Cancer Institute》1992,84(16):1256-1261
BACKGROUND: The clinical behavior of the tumor in patients with locally advanced bladder carcinoma is unpredictable. Current predictors of clinical behavior include depth of muscle invasion, presence of vascular invasion, proliferation rate, and loss of blood group antigens. Treatment selection would be facilitated by the development of a reliable marker of tumor progression. Functional retinoblastoma (RB) gene loss has been reported to occur in bladder carcinoma, but the significance of this loss is unknown. PURPOSE: We have evaluated the frequency of functional loss of the RB gene in locally advanced bladder carcinoma and have compared the results to known prognostic factors in the same cohort. METHODS: Forty-three study patients with pathologically well-characterized, locally advanced bladder carcinoma, who were placed in a protocol incorporating surgery and chemotherapy, were studied for known clinical and pathological prognostic indicators as well as for their Rb status. Formalin-fixed and paraffin-embedded archival primary tumor tissues were used for histological and immunohistochemical analyses. RESULTS: Altered Rb protein expression was documented in 37% of the tumor specimens. The high rate of altered Rb expression found in this cohort with advanced urothelial tumors strongly suggests that RB functional loss may be associated with tumor progression in this malignancy. Altered Rb protein expression was found to be independent of other known prognostic variables. A significantly poorer tumor-free survival rate also was noted for those patients who had a tumor with an altered Rb protein with or without vascular invasion. CONCLUSION: The high frequency of Rb alteration in locally advanced bladder carcinomas, plus the fact that a significant correlation could not be found between the Rb status and other known prognostic markers in this preliminary study, suggests that altered RB expression may be an independent prognostic marker of tumor progression in bladder cancer. 相似文献
6.
Renal cell carcinoma. A clinicopathologic and DNA flow cytometric analysis of 103 cases 总被引:2,自引:0,他引:2
D J Grignon A G Ayala A el-Naggar K I Wishnow J Y Ro D A Swanson D McLemore G G Giacco V F Guinee 《Cancer》1989,64(10):2133-2140
Renal cell carcinoma is unpredictable in outcome, although the best predictor is tumor stage, followed by histologic grade. The authors retrospectively assessed the clinicopathologic features and DNA ploidy of 103 cases of renal cell carcinoma, the latter determined by flow cytometry of formalin-fixed, paraffin-embedded tissue. The study group comprised 63 men and 40 women (age, 28-80 years; mean, 57 years). Robson stage at diagnosis was Stage I in 52 patients, Stage II in 21, and Stage III in 30. Statistically significant variables in predicting outcome were Robson stage (P less than 0.0001), DNA ploidy (P = 0.0008), mitotic rate (MR, P less than 0.0001), worst nuclear grade (WNG, P = 0.00009), predominant nuclear grade (P = 0.019), and sex (P = 0.044). Tumor size, cell type, and architectural pattern were also assessed but did not prove to be significant. Statistically significant associations occurred between DNA ploidy and WNG (P less than 0.0001), stage (P = 0.0037), and MR (P = 0.015); between WNG and MR (P less than 0.0001) and stage (P = 0.0007); and between stage and MR (P = 0.002). Cox proportional hazards regression analysis of all significant variables showed Robson stage, tumor ploidy, and MR to be independent, significant predictors of outcome. If ploidy data had not been available, WNG would have been independently significant. The authors conclude that DNA ploidy analysis provides significant predictive information on renal cell carcinoma. 相似文献
7.
8.
The effect of single and repeated UVB radiation on rabbit cornea 总被引:1,自引:0,他引:1
Miroslav Fris May-Britt Tessem Jitka Čejková Anna Midelfart 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(12):1680-1687
Background Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS 1H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea.Methods Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm2; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm2; days 1, 3, 5) to give the same overall dose (3.12 J/cm2). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS 1H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA).Results The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose.Conclusions For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS 1H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure. 相似文献
9.
Hy De Lee Euy Young Soh Hoon Sang Chi Byong Ro Kim Kyong Sik Lee Kyung Soon Song Hyun Joo Jung 《Surgery today》1990,20(2):180-185
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in
relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed
significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02
per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer
patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic
nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis
in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05)
than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without
axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy. 相似文献
10.
R L Shannon J Y Ro D J Grignon N G Ordó?ez D E Johnson B Mackay B Têtu A G Ayala 《Cancer》1992,69(11):2676-2682
Sarcomatoid carcinoma of the prostate is a rare tumor that can be difficult to distinguish from a true sarcoma. The authors report 12 patients in whom the typical light microscopic appearance of prostatic adenocarcinoma was accompanied by the appearance of spindled or pleomorphic sarcomatoid areas within the same specimen or in subsequent accessions. Immunostaining or electron microscopic study demonstrated epithelial differentiation within the sarcomatoid area(s) in 6 of the 11 patients in whom special studies were performed. All nine patients for whom follow-up data were available died of disease within 3 to 48 months (median time until death, 12.0 months) after the appearance of the sarcomatoid carcinoma, and the clinical course in each instance was characterized by aggressive local recurrence. Our experience confirms that sarcomatoid carcinoma of the prostate is an aggressive variant of prostatic adenocarcinoma. 相似文献