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91.
H Saito  I Ono  S Ebihara  T Yoshizumi  S Ikeda  R Ono 《Gan no rinsho》1985,31(13):1665-1668
Seven cases of head and neck carcinoma are presented. They were first noticed by sputum cytology, which was ordered to check lung cancer because of hemosputum (three cases), or in a general check-up of asymptomatic individuals. None of them had lung cancer, and three were found to have piriform sinus carcinoma, two mesopharynx carcinoma, and two vocal cord carcinoma. All seven cases were histologically diagnosed as squamous cell carcinoma. Their clinical stages were as follows; T 1 N 0, three cases; T 1 N 1, one case; T 2 N 0, two cases; T 2 N 1, one case (UICC 1978). These cases remind us that positive sputum cytology is not only a sign of lung cancer, but also of other upper aerodigestive tract malignancies. Sputum cytology may be useful for checking asymptomatic head and neck cancer patients, though it is still too costly and time-consuming to be applied to mass screening.  相似文献   
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Background The objective of this study was to evaluate the clinical outcome of combined immunotherapy with interferon-α (IFN-α) and low-dose interleukin-2 (IL-2) for Japanese patients with metastatic renal cell carcinoma (RCC) who had undergone radical nephrectomy. Methods This study included 13 patients who were diagnosed as having metastatic RCC following radical nephrectomy. These patients received a subcutaneous injection of IFN-α (6 × 106 IU per day) three times per week and an intravenous injection of IL-2 (1.4 × 106 IU per day) twice per week. Tumor response was evaluated every 16 weeks, and as a rule, this weekly regimen was repeated 50 times in patients with evidence of objective response or stable disease. Results One of the 13 patients dropped out because of severe toxicity; hence, 12 patients were evaluable, with a median follow-up period of 18 months after the start of this combined therapy. Six patients (50.0%) achieved objective responses, with 1 complete response (CR), while only 2 (16.7%) demonstrated progressive disease. The median duration of response in the 6 responders was 13.5 months. Toxicity associated with this combined immunotherapy was limited to WHO grade 1 or 2 in these 12 patients. All patients were alive at last follow-up, and 2 remain disease-free after 1 additional patient showed a CR following surgical resection of the remaining metastatic disease. Conclusion Our preliminary experience suggests that long-term, repeated treatment with IFN-α and low-dose IL-2 is feasible in Japanese patients with metastatic RCC who have undergone radical nephrectomy. Although it will be necessary to accumulate data from a larger number of patients with a longer follow-up period, the combined immunotherapy tested in this study may become the preferred therapy for Japanese patients with metastatic RCC.  相似文献   
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Vascular endothelial growth factor (VEGF) was reported to be a potent proangiogenic factor that plays a pivotal role in both physiological and pathological angiogenesis. M475271, 4-quinazolinamine, N-(2-chloro-5-methoxyphenyl)-6-methoxy-7-[(1-methyl-4-piperidinyl) methoxy]-(9Cl), is a new anilinoquinazoline derivative that showed selective inhibition of Src kinase activity and tumor growth in vivo. Here, we examined the effect of M475271 on VEGF-induced human umbilical vein endothelial cell (HUVEC) proliferation and migration and their intracellular mechanisms. Our findings showed that M475271 pretreatment resulted in a significant inhibition of VEGF-induced HUVEC proliferation, [(3)H]thymidine incorporation, and migration. M475271 inhibited VEGF-induced Flk-1 and Src phosphorylation and their association. Confocal laser microscopic examination confirmed the inhibitory effect of M475271 on VEGF-induced Flk-1/Src association. M475271 inhibited VEGF-induced extracellular signal-regulated kinase1/2 (ERK1/2) and p38 but not Akt activation in a concentration-dependent manner. M475271, PI3-K inhibitor, and p38 inhibitor inhibited VEGF-induced HUVEC proliferation and migration. However, a MEK1/2 inhibitor inhibited VEGF-induced proliferation but not migration. These findings suggest that M475271 attenuates VEGF-induced HUVEC proliferation and migration through the inhibition of signaling pathways involving Src, ERK1/2, and/or p38. Taken together, these data indicate that M475271 may be a useful candidate for inhibition of endothelial cell proliferation and migration relevant to angiogenesis.  相似文献   
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The effect of bilirubin treatment on intestinal transport of 2,4-dinitrophenyl-S-glutathione (DNP-SG), a substrate of multidrug resistance-associated protein 2 (MRP2), after application of 1-chloro-2, 4-dinitrobenzene (CDNB), a precursor of DNP-SG, was examined in rat intestine by the in-vitro everted sac, in-situ re-circulating perfusion, and in-situ loop methods. CDNB was taken up rapidly by jejunum and ileum, and the consequent intestinal efflux of DNP-SG, a glutathione conjugated metabolite of CDNB, was significantly higher in jejunum than in ileum in the in-situ and in-vitro studies. Co-administration of bilirubin (100 microM), as well as probenecid (1 mM) or ciclosporin (100 microM), with CDNB decreased the DNP-SG efflux in jejunum significantly, but not in ileum. The suppression of DNP-SG efflux in jejunum was also observed after intravenous administration of bilirubin (85.5 micromol kg-1), in which plasma bilirubin glucuronide levels were approximately 100 microM. In the in-vitro metabolism study, bilirubin exerted no significant effect on CDNB metabolism in the intestinal S9 fraction (supernatant of 9000 g). These results suggested that the diseased states accompanied with hyperbilirubinaemia might have increased the intestinal absorption, or oral bioavailability, of MRP2 substrates by suppressing MRP2 function at the proximal intestinal region.  相似文献   
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Experimental studies have shown that adrenomedullin (AM) causes vasodilation, in part, mediated by endothelium-derived nitric oxide (NO). However, it remains to be clarified how NO is involved in AM-induced coronary vasoreactivity in humans. We examined whether NO contributes to the vasodilatory effects of adrenomedullin on human coronary arteries. In 10 patients with angiographically normal coronary arteries, adrenomedullin (low dose: 1 ng/kg/min; high dose: 10 ng/kg/min) was infused into the left coronary ostium before and after an infusion of N-monomethyl-L-arginine (L-NMMA, 40 micromol/min for 5 min), an NO synthase inhibitor. Coronary diameter and coronary blood flow (CBF) were evaluated by quantitative angiography and Doppler flow velocity measurements. Changes in these parameters in response to adrenomedullin were expressed as percent changes from baseline values. Adrenomedullin at a high dose dilated coronary arteries (3.7+/-0.5%, P<0.001). Adrenomedullin increased the coronary blood flow at both doses (low: 55.7+/-13.9%, P<0.01; high: 48.8+/-9.8%, P<0.001). After the infusion of L-NMMA, adrenomedullin-induced coronary vasodilation and increase in coronary blood flow were attenuated. These findings suggest that adrenomedullin dilates human coronary arteries through an increase in NO production, at least in part.  相似文献   
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OBJECTIVES: The purpose of this study is to provide short- and mid-term results of open aortic valvotomy (OAV) for patients with critical aortic stenosis (AS). METHODS: Between December 1993 and June 1996, 6 patients with critical AS underwent an OAV in our unit. Their ages and body weights at operation ranged from 1 to 65 days (median age, 9 days) and from 2.4 to 5.7 kg (median weight, 3.3 kg), respectively. Peak pressure gradient and diameter of the aortic valve ranged from 25 to 111 mmHg (mean value, 79 mmHg) and from 4.6 to 7.5 mm (mean diameter, 6.1 mm), respectively. OAV comprised the valvular commissurotomy and excision of the myxomatous nodules with cardiopulmonary bypass. RESULTS: No early or late death occurred. Mean peak pressure gradient across the aortic valve was reduced to 33 mmHg (from 15 to 44 mmHg) with no aortic insufficiency in 2 patients and trivial insufficiency in 4. During the follow-up period of 6 to 9 years, 3 out of 6 patients required no reintervention. The other 3 patients required repeated valvotomy for recurrent stenosis within 0.2 to 1.3 years after the operation. Of these, 2 patients required the Ross procedure at 7 years of age or older, and another at 6 years of age awaits the Ross procedure. CONCLUSION: OAV for critical AS was effective without causing mortality or significant aortic insufficiency. Our current strategy comprising the initial OAV and "delayed Ross procedure" for recurrent stenosis with or without insufficiency is a promising therapeutic option for infants with critical AS.  相似文献   
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