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991.
Kishimoto Y Hirono M Sugiyama T Kawahara S Nakao K Kishio M Katsuki M Yoshioka T Kirino Y 《Neuroreport》2001,12(13):2919-2922
To elucidate the functional role of phospholipase Cbeta4 (PLCbeta4), which is highly expressed in the Purkinje cells of the rostral cerebellum, cerebellar long-term depression (LTD) and delay and trace eyeblink conditioning were investigated in PLCbeta4-deficient mice. Rostral cerebellar LTD and delay eyeblink conditioning were severely impaired, whereas trace eyeblink conditioning was not. These results indicate that PLCbeta4 is essential for LTD in the rostral cerebellum and delay conditioning, but not trace conditioning. Rostral cerebellar LTD may be required as a neural substrate for delay conditioning, but is not required for trace conditioning. 相似文献
992.
A 65-year-old man was diagnosed to have Crohn's disease in 1989. In 1991, frequent bronchitis developed, and bronchoesophageal fistula was diagnosed by esophagography. On esophagography and aortography, the disease was diagnosed to be Type IV based on Braimbridge's classification accompanied by pulmonary sequestration. A thoracoscope-assisted fistelectomy was performed. This paper reports the findings of a fistelectomy assisted by thoracoscopy for the treatment of a Type IV bronchoesophageal fistula according to Braimbridge's classification accompanied by Crohn's disease. 相似文献
993.
Akihiro Hirata Tetsuya Tsukamoto Hiroki Sakai Shinji Takasu Hisayo Ban Toshio Imai Yukari Totsuka Rena Nishigaki Keiji Wakabayashi Tokuma Yanai Toshiaki Masegi Masae Tatematsu 《Food and chemical toxicology》2008,46(6):2003-2009
Carcinogenic potential of heterocyclic amines (HCAs) was investigated using an in vivo 5-week initiation assay with quantitative evaluation of glutathione S-transferase placental form (GST-P) positive foci in rat liver. Numbers of GST-P positive foci were significantly increased with individual administration of six different HCAs, indicating utility of the assay. It was therefore applied to investigate risk with multiple HCAs in combination. Unexpectedly, concomitant treatment with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) did not result in any additive carcinogenicity. In the rats taking MeIQx prior to PhIP the value was almost equal to the sum total of individual data, indicating additive initiation activities. In contrast, simultaneous or prior administration of PhIP rather exerted inhibitory effects on the carcinogenic potential of MeIQx. Moreover, microarray and quantitative RT-PCR assessment revealed that PhIP induced cytochrome P450 1A1, responsible for both activation and detoxification of HCAs, more strongly than MeIQx. It is noteworthy that complex exposure to multiple HCAs is not necessarily associated with increased risk of carcinogenesis because they are simultaneously and continuously ingested under normal circumstances. 相似文献
994.
Yamamoto T Inoue F Mutoh T Tatematsu H Yamataka K Sakurai T Kawahara H 《Gan to kagaku ryoho. Cancer & chemotherapy》2001,28(9):1291-1294
We treated a patient with intra-peritoneal recurrent tumor from colon cancer who responded completely to chemotherapy of combined low-dose Leucovorin (LV) and 5-fluorouracil (5-FU). The patient was a 75-year-old man. He underwent resection of the transverse colon, sigmoid colon and distal stomach for colon and gastric cancers. Nine months after the operation, his CEA level increased to 39.5 ng/ml and a CT scan revealed an intra-peritoneal tumor measuring about 5 cm. He received chemotherapy of 30 mg/day of LV that was injected in a bolus and 500 mg/day of 5-FU that was given i.v. by continuous infusion for 10 days. At the end of 2 cycles of this regimen, CT scan demonstrated complete tumor remission and the patient's CEA level decreased to normal level. After an additional cycle of this regimen, he received modulated chemotherapy combined with l-Leucovorin and 5-FU as an outpatient. However, after 3 months of treatment, a recurrent tumor was detected in the same portion and the first regimen was re-started for 5 days. After 4 cycles of treatment the tumor disappeared completely from a CT scan. It is important to investigate effective regimens that do not reduce the quality of life of the patient. This clinical experience suggests that a low-dose LV/5-FU therapy may be beneficial to patients with recurrent colon cancer. Further investigation is necessary to establish an effective regimen that can be given for a long period without adverse effects on quality of life. 相似文献
995.
K Furuse M Kawahara Y Nishiwaki M Fukuoka M Takada M Miyashita Y Ohashi 《Journal of clinical oncology》1999,17(10):3195-3200
PURPOSE: To determine the maximum-tolerated doses (MTDs) of vinorelbine (VRB), mitomycin (MMC), and cisplatin (P), given in two courses every 28 days to previously untreated patients with stage IIIB or IV non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: At least three or four patients were entered at each dose level. The starting dose was 20 mg/m(2) for VRB on days 1 and 8 and 4 mg/m(2) for MMC on day 1, with a fixed dose of P 80 mg/m(2) on day 1 every 4 weeks. MMC was increased to 6 mg/m(2) at dose level 2 and subsequently to 8 mg/m(2) at dose level 4. At dose level 3, VRB was increased to 25 mg/m(2). Twenty-five patients were entered onto the phase I study and 19 patients were entered onto phase II study. RESULTS: Nadir leukocyte and platelet counts decreased at each dose level. At dose levels 1 and 2, the dose-limiting toxicity (DLT) was not seen, but at dose levels 3 and 4, DLT was encountered in two patients. Nearly half the patients at dose level 4 had dose reduction due to grade 4 leukopenia. A mathematic model of all toxicity suggested that dose level 4 (VRB 25 mg/m(2) on days 1 and 8 and MMC 8 mg/m(2) and P 80 mg/m(2) on day 1, every 4 weeks) would be the recommended dose for phase II study at which grade 4 toxicity is expected in = 25% of patients over two courses. Of the 25 assessable patients in the phase I study, 13 achieved a partial response and one had a complete response for a response rate of 56. 0%. Of the 19 assessable patients in the phase II study, 12 had a partial response (63.2%; 95% confidence interval, 38.4% to 83.7%). Grade 3 and 4 leukopenia was observed in 19 (100%), and grade 3 thrombocytopenia was seen in seven (36.8%). Median survival time was 10.7 months and the 1-year survival rate was 43.2% in the 44 assessable patients. CONCLUSION: The VRB/MMC/P regimen is effective against NSCLC, and its efficacy should be confirmed through a randomized study. 相似文献
996.
K Furuse M Fukuoka M Kawahara H Nishikawa Y Takada S Kudoh N Katagami Y Ariyoshi 《Journal of clinical oncology》1999,17(9):2692-2699
PURPOSE: A phase III study was performed to determine whether concurrent or sequential treatment with radiotherapy (RT) and chemotherapy (CT) improves survival in unresectable stage III non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients were assigned to the two treatment arms. In the concurrent arm, chemotherapy consisted of cisplatin (80 mg/m(2) on days 1 and 29), vindesine (3 mg/m(2) on days 1, 8, 29, and 36), and mitomycin (8 mg/m(2) on days 1 and 29). RT began on day 2 at a dose of 28 Gy (2 Gy per fraction and 5 fractions per week for a total of 14 fractions) followed by a rest period of 10 days, and then repeated. In the sequential arm, the same CT was given, but RT was initiated after completing CT and consisted of 56 Gy (2 Gy per fraction and 5 fractions per week for a total of 28 fractions). RESULTS: Three hundred twenty patients were entered onto the study. Pretreatment characteristics were well balanced between the treatment arms. The response rate for the concurrent arm was significantly higher (84. 0%) than that of the sequential arm (66%) (P =.0002). The median survival duration was significantly superior in patients receiving concurrent therapy (16.5 months), as compared with those receiving sequential therapy (13.3 months) (P =.03998). Two-, 3-, 4-, and 5-year survival rates in the concurrent group (34.6%, 22.3%, 16.9%, and 15.8%, respectively) were better than those in the sequential group (27.4%, 14.7%, 10.1%, and 8.9%, respectively). Myelosuppression was significantly greater among patients on the concurrent arm than on the sequential arm (P =.0001). CONCLUSION: In selected patients with unresectable stage III NSCLC, the concurrent approach yields a significantly increased response rate and enhanced median survival duration when compared with the sequential approach. 相似文献
997.
EFFECTS OF MILD AEROBIC EXERCISE AND A MILD HYPOCALORIC DIET ON PLASMA LEPTIN IN SEDENTARY WOMEN 总被引:6,自引:0,他引:6
Tetsuya Okazaki Etsuro Himeno Hiroki Nanri Hajime Ogata & Masaharu Ikeda 《Clinical and experimental pharmacology & physiology》1999,26(5-6):415-420
1. The present study was conducted to investigate whether mild aerobic exercise and a mild hypocaloric diet, instead of severe restrictions on caloric intake, would affect weight reduction and plasma leptin concentrations. 2. Forty-one middle-aged sedentary women (15 obese and 26 non-obese) participated in a 12 week lifestyle-modification programme to reduce cardiovascular risk factors. Bodyweight, body composition, plasma leptin concentrations, serum lipid profiles, fasting plasma glucose and fasting plasma insulin were measured before and after the 12 week intervention. The intervention consisted of aerobic exercise, corresponding to approximately 50% of maximal oxygen consumption, and personal diet counselling. 3. Bodyweight decreased by (mean +/- SD) 3.9 +/- 3.4 kg in the obese group (P < 0.05) and by 1.7 +/- 1.8 kg in the non-obese group (P < 0.05). The plasma leptin concentration decreased significantly from 14.7 +/- 5.3 to 8.9 +/- 3.6 ng/mL in the obese group (P < 0.001) and from 7.6 +/- 3.9 to 5.6 +/- 2.2 ng/mL in the non-obese group (P < 0.01). 4. Overall, for all subjects, both pre- and postintervention, the plasma leptin concentration was significantly correlated with body mass index (BMI; pre-intervention: r = 0.73, P < 0.0001; postintervention: r = 0.67, P < 0.0001), fat mass (FM; pre-intervention: r = 0.74, P < 0.0001; postintervention: r = 0.63, P < 0.0001) and fasting plasma insulin (pre-intervention: r = 0.66, P < 0.001; postintervention: r = 0.45, P < 0.01). The change in plasma leptin concentration was significantly correlated with the respective changes in BMI (r = 0.64, P < 0.0001), FM (r = 0.48, P < 0.01) and fasting plasma insulin (r = 0.58, P < 0.0001). Interestingly, the ratio of plasma leptin concentration to BMI or FM diminished significantly after intervention. In addition, we found that the plasma leptin concentration decreased in participants whose FM did not decrease. These results suggest that the production of leptin per unit FM decreased after intervention. 5. Mild aerobic exercise and a mild hypocaloric intake decreased body mass and the plasma leptin level in Japanese middle-aged sedentary women. This decrease in plasma leptin levels was likely to be associated with weight reduction plus some unknown factor(s). 相似文献
998.
Discrimination of double primary lung cancer from intrapulmonary metastasis by p53 gene mutation 总被引:3,自引:0,他引:3
Matsuzoe D Hideshima T Ohshima K Kawahara K Shirakusa T Kimura A 《British journal of cancer》1999,79(9-10):1549-1552
When multiple synchronous lung tumours are identified, discrimination of multicentric lung cancers from intrapulmonary metastases by clinical findings is often difficult. We used genetic alterations in p53 gene as a discrimination marker of double primary lung cancers from single lung cancer with intrapulmonary metastasis. Twenty of 861 patients with primary lung cancer who underwent lung resection were selected as subjects because they showed synchronous double solid tumours of the same histological type in the unilateral lung without distant metastases. In addition, they had been diagnosed as lung carcinoma with intrapulmonary metastasis by clinical and histological findings. DNAs were extracted from paraffin-embedded tissue of paired tumours from these 20 patients. Exons 5-9 of the p53 gene were examined for genetic alterations in the tumours by polymerase chain reaction, single-strand conformation polymorphism analysis and subsequent DNA sequencing analysis. Three different patterns in the distribution of p53 mutations in double lung tumours were observed: [A] mutation in only one of the tumours (four cases), [B] different mutations in the tumours (two cases), and [C] same mutation in both tumours (one case). The cases of [A] or [B] patterns could be classified as double primary lung cancers, while the case of the [C] pattern was suggested to be lung cancer with intrapulmonary metastasis. These results suggested that the multicentric cancers were more frequent than the intrapulmonary metastatic cancers in double cancer cases. 相似文献
999.
Molecular Basis of Pituitary Oncogenesis 总被引:6,自引:0,他引:6
1000.
Harada K Tazunoki Y Ide Y Takeuchi A Kawahara J Suzuki T 《The Journal of pharmacy and pharmacology》2000,52(3):321-325
We examined whether pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) affected 5-fluorouracil-induced thrombocytopenia without inducing more severe intimal thickening after injury to rat carotid arteries. Rat carotid arteries were injured using a balloon catheter on day 0. 5-Fluorouracil (100 mg kg(-1)) or vehicle was intravenously administered on day 1 in balloon-injured rats. PEG-rHuMGDF (100 microg kg(-1)) or vehicle was intravenously administered once a day on days 1-5 to balloon-injured rats given 5-fluorouracil or vehicle. 5-Fluorouracil (100 mg kg(-1), i.v.) caused a significant decrease in the platelet count from day 3 and peaked on days 7-9 in balloon-injured rats. PEG-rHuMGDF (100 microg kg(-1), i.v.) reduced this decrease on days 9 and 11. The administration of PEG-rHuMGDF did not accelerate the intimal thickening of balloon-injured arteries in rats treated with 5-fluorouracil compared with control balloon-injured rats. PEG-rHuMGDF did not increase plasma tumour growth factor-beta1 (TGF-beta1) from days 0-9 in balloon-injured rats compared with control balloon-injured rats. These results suggest that PEG-rHuMGDF ameliorated 5-fluorouracil-induced thrombocytopenia without accelerating the intimal thickening of balloon-injured arteries. 相似文献