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H Tsukamoto T Kurokawa K Hirata S Ishibashi HK Mishima 《Canadian Metallurgical Quarterly》1998,46(5):987-991
We investigated the effect of two isomers of retinoic acid (RA), all-trans RA and 9-cis RA, on the proliferation of Y79 human retinoblastoma cells. The two isomers inhibited the cell proliferation in a concentration-dependent manner. The IC50 for this inhibition by all-trans RA and 9-cis RA was 1.50 and 0.15 microM, respectively. The inhibitory effect of 9-cis RA on Y79 cell growth was observed within 24 hr, thereafter the cell number was gradually decreased. In contrast, no inhibition by all-trans RA of Y79 cell growth was observed within 24 hr, thereafter the cell number was slightly increased. In these cases, the cell viability at 4 days after the addition of 9-cis RA and all-trans RA was more than 90% and 95%, respectively. These results indicate that the two RA inhibit the proliferation of Y79 human retinoblastoma cells without inducing the cell death and that the effect of 9-cis RA on the inhibition of Y79 cell growth is much greater than that of all-trans RA. 相似文献
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Minority carrier diffusion length InxGa1?xP LPE layers has been measured using the electron beam method. It has been found that this parameter significantly changes with the composition of the alloy. The measured relationship proves that minority carrier mobility in InxGa1?xP alloys with low indium content strongly depends on the alloy composition. It is suggested that alloy scattering may be responsible for this behaviour. The effect of doping the InxGa1?xP LPE layers with nitrogen has also been investigated. Results indicate that carrier mobility drops when the nitrogen concentration exceeds certain limits and this most probably can be ascribed to carrier scattering on the nitrogen centers. 相似文献
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A Mustonen HK Ploos van Amstel R Berger MK Salo L Viinikka KO Simola 《Canadian Metallurgical Quarterly》1997,17(10):964-966
Presentation of 11 cases of retroperitoneal sarcoma. Mean time from the beginning of symptoms to diagnosis is 6 months. The primary complementary study is CT. Surgery was performed in all cases, using complete resection in 6 cases, and partial resection in 5. Ten patients relapsed. 9 of which were treated with surgical rescue, in one or more occasions; chemotherapy was added in 6 cases and radiotherapy in 7. Survival at five years is 68%, with a mean follow-up of 66 months. 相似文献
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HY Song SI Park HY Jung SB Kim JH Kim SJ Huh TH Kim YK Kim S Park HK Yoon KB Sung YI Min 《Canadian Metallurgical Quarterly》1997,203(3):747-752
PURPOSE: To evaluate the clinical effectiveness of a polyurethane-covered, retrievable, self-expandable metallic stent and hook catheter in the treatment of esophageal strictures. MATERIALS AND METHODS: Stents were constructed of 0.4-mm stainless steel wire in a cylindric zig-zag configuration of six to nine bends. Four to eight stents were connected in tandem by dipping in a polyurethane solution. A nylon loop was hooked inside to each bend of the proximal portion of the stent and strung with a thread. Under fluoroscopic guidance, 22 stents were placed in 16 patients with a malignant stricture and five patients with a benign stricture. The stent was removed with a hook catheter 2 months after placement in patients with a benign stricture and when complications occurred in patients with a malignant stricture. All patients had dysphagia with ingestion of soft foods or liquids. RESULTS: Stent placement was technically successful and well tolerated in 20 patients. In one patient, the stent was misplaced but relocated successfully. After stent placement, all patients were able to ingest solid and/or soft foods without dysphagia. After stent removal, strictures showed improvement but recurred in two patients. CONCLUSION: Use of polyurethane-covered, retrievable expandable stents seems to be a feasible and effective method of treatment of benign and malignant esophageal strictures. 相似文献