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991.
MP Waring ES Paul CW Beausang RM Clark RA Cunningham T Davinson SA Forbes DB Fossan SJ Gale A Gizon J Gizon K Hauschild IM Hibbert AN James PM Jones MJ Joyce DR LaFosse RD Page I Ragnarsson H Schnare PJ Sellin J Simpson P Vaska R Wadsworth PJ Woods 《Canadian Metallurgical Quarterly》1995,51(5):2427-2438
992.
993.
Transient evoked otoacoustic emissions (TEOAE) have been evaluated as a means of monitoring cochlear function in patients receiving the chemotherapeutic agents cisplatin and carboplatin (-cis-diammine, 1,1-cyclobutane dicarboxylate (2) -0,0-platinum). Patients receiving these drugs were monitored prospectively with pure tone audiometry (PTA), tympanometry and TEOAE. Data was collected on 22 subjects receiving cisplatin and nine subjects receiving carboplatin. Significant deterioration in both PTA thresholds and TEOAE energy levels (with no change in tympanometry) were detected in the cisplatin group. No significant deterioration in audiological parameters occurred in the carboplatin group. It is indicated that cisplatin has a significant ototoxic effect in the majority of patients, whereas any ototoxic effect of carboplatin was undetectable. Our findings were different from previous studies in that the measurable changes in TEOAE occurred later than changes in the pure tone audiogram for the cisplatin group. 相似文献
994.
A spontaneous splenic rupture occurred in a 31 year old patient suffering from infectious mononucleosis. An echography and an abdominal CT Scan revealed a rupture of the inferior pole of the spleen with a hemoperitoneum. A conservative surgical treatment was performed. Postoperative course was uneventful. This case-report draws the attention to the possibility of a conservative surgical treatment of a splenic rupture in the course of infectious mononucleosis. This attitude avoids the complications of splenectomy. 相似文献
995.
Risk factors in congenital anal atresias 总被引:1,自引:0,他引:1
Congenital anal atresias were studied in a small geographical area in 225,752 consecutive births. For each of the 108 new cases studied during the period 1979 to 1995, more than 50 factors were compared in probands and in controls. The prevalence rate of congenital anal atresias was 4.8 per 10,000 births. Sex ratio was 0.96. Prenatal diagnosis was performed in 14 cases and 11 cases were induced abortions. The more common types of associated malformations in the 45 non syndromic affected cases with at least one major anomaly other than anal atresia were renal agenesia, genital anomalies and ventricular septal defect. At births infants with anal atresia and other malformations were smaller, weighted less and their head circumference was lower than in controls. Placental weight was also lower than in controls. Pregnancies with anal atresia were more often complicated by threatened abortion, oligoamnios and polyhydramnios. Mothers of children with congenital anal atresia took more often drugs during pregnancy than mothers of controls. Fathers of children with anal atresia were more often exposed to occupational hazards than fathers of controls. There was a significant association between anal atresia and consanguinity of parents (p < 0.05). The recurrence risk for first degree relatives of probands was 3.7%. First degree relatives of probands had more than twice the prevalence of non-anal atresia malformations than controls. 相似文献
996.
Transformation progression toward more malignant behavior often results from a loss of epithelial cell behavior, especially cell-cell adhesion. E1A cooperates with ras to transform primary epithelial cells such that they maintain epithelial cell differentiation, including the proper localization of adherens junctions (AJs). Second exon mutants of E1A 12S cooperate with ras to produce a more aggressively transformed phenotype, termed hypertransformation, that includes the loss of adhesion. Such hypertransformation can also be achieved by the addition of activated Rac1 to cells expressing wild-type E1A and ras, suggesting that actin reorganization may be important for the hypertransformed phenotype. Primary epithelial cells expressing hypertransforming mutants of E1A or V12Rac1 exhibit the loss of cortical actin filaments. In these cells, AJ complexes do not incorporate alpha-catenin, fail to associate with the cytoskeleton, and fail to localize to the plasma membrane, resulting in the destabilization of the AJ components and a loss of function. Loss of these epithelial cell characteristics predisposes these cells to a more malignant phenotype due to the loss of cell-cell adhesion. Taken together, these results suggest a novel mechanism of regulation of AJ function in tumor progression that involves the correct targeting of the AJ components, and this is affected by the status of cortical actin, which can be differentially affected by E1A or Rac1. 相似文献
997.
MP Catinot B Bastide G Suarez-Kurtz Y Mounier 《Canadian Metallurgical Quarterly》1998,362(2-3):221-227
The pyrimidine nucleotide, uridine triphosphate (UTP), was tested with skinned skeletal muscle fibers in order to investigate the UTP-sensitive pathway of Ca2+ release from the sarcoplasmic reticulum. The presence of ryanodine (200 microM), ruthenium red (10 microM) or heparin (2.5 mg/ml) did not affect the tension elicited in the presence of UTP, demonstrating that the UTP-induced Ca2+ release involved neither ryanodine nor inositol triphosphate-sensitive channels. Drugs such as compound 48/80 or cyclopiazonic acid used to inhibit Ca2+-ATPase in its reverse function appeared to be, respectively, non-specific or without any inhibitory effect on the tension induced by UTP. Finally, the UTP-induced tension as well as the trifluoperazine-induced tension were abolished in the presence of spermidine (50 mM), supporting the hypothesis that the UTP-sensitive pathway of the SR Ca2+ release might occur through the uncoupled calcium ATPase. 相似文献
998.
Recurrent colorectal carcinoma constitutes a major health care problem, with 90,000 patients diagnosed annually with metastatic disease. Recent advances have offered treatment to selected patients with liver, lung, and intra-abdominal metastases. Resection of liver secondary tumors improves 5-year survival from 0% to approximately 30% and offers the only possibility for cure. As experience mounts, hepatic surgery can be performed with quite acceptable morbidity and mortality. Adjuvant therapies are being developed that may improve results with surgery alone. Cryoablation is a new technique that appears to effectively eradicate liver tumors, but its role remains to be defined. In patients with unresectable disease, the benefit of hepatic artery infusion of chemotherapy is unproven. Resection of pulmonary metastases significantly improves survival in patients with solitary nodules. Consistent data regarding the benefit of pulmonary metastatectomy in patients with multiple nodules are not available. Combined cytoreductive surgery and intraperitoneal hyperthermic chemotherapy is being investigated as a treatment for peritoneal carcinomatosis from colorectal cancer. Although selected patients may benefit, this combined treatment modality appears to be less effective in patients with colorectal cancer than with other types of cancer. 相似文献
999.
Therapeutic preparations of FSH, used primarily for treatment of infertility, are calibrated by in vivo bioassay against international standards (IS) derived from different sources deemed appropriate to their use according to pharmacopoeial monographs. Menotrophins, which have been used for several decades to treat infertility, have been calibrated against the IS for urinary FSH and LH (ISU) but are now being replaced by highly purified urinary FSH or rDNA-derived FSH (rFSH). The aim of this study was to evaluate two preparations of human rFSH and one preparation of highly purified urinary FSH as candidate WHO IS for bioassay in an international collaborative study by 27 laboratories in 12 countries, and to characterise them in a range of in vitro bioassays and immunoassays. The biological activity of the three candidate standards was confirmed by all laboratories using all assays contributed to the study. Dose-response relationships by in vivo bioassay for any of the candidate standards did not differ significantly from that for the ISU. Dose-response relationships obtained in in vitro bioassays and immunoassays were also broadly similar among these preparations although dose-response lines for some preparations appeared to be non-parallel in some immunoassays. For each of the three candidate IS, estimates of the relative potency in terms of ISU by in vivo bioassay did not differ significantly between laboratories. In contrast estimates by immunoassays and in vitro bioassays showed significant differences between laboratories. Estimates of relative potency of the highly purified candidate IS materials in terms of one another exhibited less inter-laboratory variability than estimates in term of ISU. Each of the candidate standards showed adequate stability to serve as an IS. On the basis of the results of this study rFSH (code 92/642) was established as the first IS for FSH, human, recombinant for bioassay with an assigned unitage of 138 IU per ampoule and urinary FSH (code 92/512) was established as the first IS for FSH, human, urinary (urofollitropin) for bioassay with an assigned unitage of 121 IU per ampoule, based on their respective calibration by in vivo bioassay in terms of ISU. These assignments of unitage maintain continuity of unitage for preparations in therapeutic use and also appear to be consistent with one another. 相似文献
1000.
L Bartalena C Marcocci ML Tanda L Manetti E Dell'Unto MP Bartolomei M Nardi E Martino A Pinchera 《Canadian Metallurgical Quarterly》1998,129(8):632-635
BACKGROUND: It is unclear whether smoking affects the course of Graves ophthalmopathy and therapeutic outcomes. OBJECTIVE: To observe smoking behavior in a randomized study of the effect of radioiodine therapy on ophthalmopathy and in a case series of patients with Graves ophthalmopathy receiving orbital radiation therapy and glucocorticoids. DESIGN: Randomized, single-blind study of smoking and mild ophthalmopathy after radioiodine therapy (study 1) and a retrospective cohort study of the association between smoking and response of severe ophthalmopathy to treatment (study 2). SETTING: University medical center. PATIENTS: 300 patients with mild ophthalmopathy (study 1) and 150 patients with severe ophthalmopathy (study 2). INTERVENTION: In study 1, patients received radioiodine alone or radioiodine and a 3-month course of oral prednisone (initial dosage, 0.4 to 0.5 mg/kg of body weight per day). In study 2, patients received high-dose oral prednisone for 6 months (initial dosage, 80 to 100 mg/d) and underwent orbital radiation therapy by linear accelerator (cumulative dose, 20 Gy per eye over 2 weeks). MEASUREMENTS: Degree of ophthalmopathy was assessed by overall evaluation (inflammatory changes, proptosis, extraocular muscle dysfunction, corneal involvement, and optic neuropathy). RESULTS: In study 1, ophthalmopathy progressed in 4 of 68 nonsmokers (5.9% [95% CI, 3% to 9%]) and 19 of 82 smokers (23.2% [CI, 13% to 33%]) who received radioiodine alone (P = 0.007). Ophthalmopathy was alleviated in 37 of 58 nonsmokers (63.8% [CI, 51% to 78%]) and 13 of 87 smokers (14.9% [CI, 10% to 26%]) who received radioiodine plus prednisone (P < 0.001). In study 2, 61 of 65 nonsmokers (93.8% [CI, 90% to 98%]) and 58 of 85 smokers (68.2% [CI, 57% to 78%]) responded to treatment (P < 0.001). CONCLUSIONS: Cigarette smoking increases the risk for progression of ophthalmopathy after radioiodine therapy and decreases the efficacy of orbital radiation therapy and glucocorticoid therapy. 相似文献