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51.
J Moreno Sierra ML Maestro de las Casas J Chicharro Almarza MD Ortega Heredia J López García-Asenjo C Merino Sánchez E Blanco Jiménez A Silmi Moyano L Rsesel Estévez 《Canadian Metallurgical Quarterly》1997,50(8):855-866
OBJECTIVE: The clinical course of transitional cell carcinoma of the bladder can be difficult to predict due to its potential to invade the muscle layer and/or develop to a high grade lesion. Bladder carcinoma can arise from genetic changes that may activate the oncogenes (-c-erbB2, c-erbB1, c-myc, ras, etc.) and/or inactivate the suppressor genes (p53, Rb). The aim of the present study is to continue a study protocol on the molecular biology of bladder tumors. METHODS/RESULTS: From January, 1993 to January, 1995, 85 patients were studied. These patients were divided into two groups: the first group comprised 14 controls of urothelial tissue and the second comprised 65 cases of transitional cell carcinoma of the bladder. p53 expression was determined by an immunohistochemical method (NCL-p53-DO7 monoclonal antibody). Quantification of the p8 oncoprotein in cytosol and EGFR (epidermal growth factor receptor) in membrane was performed by ELISA (Oncogene Science) and RIA (Vienna Lab), respectively. A statistically significant relationship between the expression of p53 and EGFR with tumor stage and grade was found. Quantification of p185 and EGFR showed higher values in the tumor tissue than in the control samples, but a worse survival could not be determined. CONCLUSIONS: The present study shows that p53 expression can be considered to be a prognostic factor. It provides useful information on the aggressive behaviour of the tumor and has a direct relation with the survival rates. 相似文献
52.
53.
N. B. Kavukcuoglu E. Arteaga-Solis S. Lee-Arteaga F. Ramirez A. B. Mann 《Journal of Materials Science》2007,42(21):8788-8794
Absence of fibrillin 2 (Fbn2), a non-collagenous bone protein, causes a connective tissue disorder called congenital contractural arachnodactyly (CCA)
and has been associated with decreased bone mineral density. Nanoindentation and Raman microspectroscopy have been used to
compare the mechanical and chemical properties of cortical bone from femora of Fbn2−/− deficient mice and their wild-type controls (Fbn2+/+). It was found that Fbn2−/− bones have significantly lower hardness and elastic modulus compared to Fbn2+/+ bones, especially in the mid-cortical section. The Raman analysis showed little difference with genotype except for a decrease
in type-B carbonate substitution in the endosteal region of Fbn2−/− bones. The results indicate that Fbn2 plays a direct role in determining the mechanical properties of bone. 相似文献
54.
55.
ML Israel DA Connolly RE von Heyn JM Rock PW Smith 《Canadian Metallurgical Quarterly》1993,24(4):343-355
Fifty-two case-hardened, severely self-abusive and aggressive autistic and retarded students, living in six different community residences, were trained to exit their residences, without the presence or assistance of staff, when a fire alarm sounded at night. On a pretest, prior to an 11-week period of intensive environmental and behavioral interventions, only 25% of the students exited within 2 1/2 minutes and independent of staff assistance. At posttest, 100% exited successfully, in a mean evacuation time of 60 seconds. The study was conducted at the Behavior Research Institute (BRI). 相似文献
56.
Endogenous prostacyclin (PGI2; epoprostenol) is a potent endothelium-derived pulmonary vasodilator. However, the effects of exogenous PGI2 on isolated arteries could be either relaxant or contractile, depending on the species and organ studied. The present study investigated the distal pathways involved in the PGI2-induced contraction in rat intrapulmonary artery (PA) and relaxation in lamb PA. When vessels were precontracted with 30 mM K+, PGI2 (1 microM) induced relaxation in lamb PA but caused contraction in rat PA. Use of 30 mM K+, phenylephrine, serotonin, angiotensin II, or hypoxia to precontract the vessels did not alter the contractile effect of PGI2 in rat PA. Nevertheless, PGI2 produced a mild relaxation in rat PA precontracted by U-46619, a thromboxane A2 (TxA2)-receptor agonist, whereas the TxA2-receptor blocker SQ-29548 (0.1-0.5 microM) abolished the contractile response in rat PA. These data suggest that PGI2-induced contraction is mediated by activation of TxA2 receptors. The PGI2-induced modest relaxation in rat PA, which was only observed when TxA2 receptors were blocked by SQ-29548, suggests that the PGI2-mediated vasorelaxant pathway is diminished in these vessels. Simultaneous application of forskolin, an adenylate cyclase activator, and rolipram, a phosphodiesterase inhibitor, caused similar relaxation in both rat and lamb PA. This suggests that the adenosine 3',5'-cyclic monophosphate-dependent relaxing pathway is intact in rat PA and is comparable to that in lamb PA. On the basis of these data, we conclude that the pathways responsible for the paradoxical effects of PGI2 on rat and lamb PA are located upstream of the adenosine 3',5'-cyclic monophosphate-dependent relaxing pathway and that a paucity of PGI2 receptors in rat PA may be responsible. 相似文献
57.
58.
ML McLaws C Murphy P Taylor M Ferson J Gold R Donnellan D Dalton 《Canadian Metallurgical Quarterly》1997,18(11):778-780
The rate of nosocomial respiratory syncytial virus (RSV) infection was measured in a large pediatric hospital using an incidence density method. The at-risk days for nosocomial RSV were summed during a defined winter period in which there were 54 admissions with community-acquired RSV infection giving a rate of 2.9 cases per 1,000 at-risk days (95% confidence interval, 0.3-5.4 per 1,000). 相似文献
59.
Only 19 cases of metastases at the cannula insertion site after laparoscopy for gynecological malignancy have been reported in the literature. One case has been diagnosed with cervical squamous cell carcinoma, whereas the others have been diagnosed with ovarian cancer and borderline ovarian tumor. We present a novel case of laparoscopy-site abdominal wall metastasis from endometrial cancer after laparoscopic-assisted vaginal hysterectomy (LAVH). The 56-year-old female patient exhibited metastases of an abdominal wall trocar site and a perineal site after undergoing LAVH and laparoscopic-assisted (LA) bilateral pelvic lymph node sampling as well as LA para-aortic lymph node sampling for treating endometrial carcinoma, surgical staging IIIC, G3. The interval between the surgical extirpation of endometrial carcinoma and diagnosis of the tumor recurrence was 6 months, suggesting that overmanipulation of the diseased organ during laparoscopic surgery may have resulted in tumor spillage, intraperitoneal dissemination, and wound contamination. Although this procedure has been proven beneficial to patients with benign disease or early-stage gynecologic malignancies, laparoscopic-assisted vaginal hysterectomy may not be efficacious to eradicate advanced gynecological malignancy. 相似文献
60.
T Smith AK Hewson CI Kingsley JP Leonard ML Cuzner 《Canadian Metallurgical Quarterly》1997,150(6):1909-1917
Acute, monophasic experimental allergic encephalomyelitis (EAE) in the Lewis rat shows pathological similarities to the human disease multiple sclerosis (MS). Rats that recover from EAE are essentially resistant to disease reinduction, unlike MS in which relapses are frequently associated with common bacterial and viral infections. As macrophage-derived interleukin (IL)-12 is a critical component of innate resistance to bacterial infection and appears to directly activate encephalitogenic T cells in vivo, the ability of this cytokine to reinduce paralysis in EAE was examined. Paralytic disease was exacerbated by intraperitoneal IL-12 administration and could be reinduced up to 1 week after recovery from the primary clinical episode. Concomitant with worsening of initial clinical signs and relapse was an increase in the ratio of macrophages to T cells in brain stem perivascular cuffs and the expression of inducible nitric oxide synthase in cells with both macrophage and microglial morphology. These findings suggest that IL-12 may contribute to macrophage-mediated disease exacerbation and relapse in patients with MS. 相似文献