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941.
Takahashi T Ogawa Y Kobayashi T Sonobe H Seguchi H Tani T Yoshida S 《International journal of molecular medicine》2004,13(5):661-664
Selective inhibition of COX-2 is thought to prevent carcinogenesis in some malignant tumors. In this study, in an effort to enhance the effectiveness of osteosarcoma treatment, we investigated the effect of a selective inhibitor of COX-2, with or without irradiation. We also asked whether selective COX-2 inhibitors increase the effect of X-ray irradiation, with regard to reactive oxygen species (ROS) formation in an osteosarcoma cell line. Our results showed that the presence of COX-2 inhibitor without irradiation results in faint spots of ROS formation that do not appear in the absence of COX-2 inhibitor. However, COX-2 inhibitor did not induce ROS formation when combined with irradiation. Thus, radiotherapy with selective COX-2 inhibitions has limitations in the treatment of radioresistant osteosarcoma to obtain the effective achievement, it is indispensable to combine another agent in future studies. 相似文献
942.
Hydrogen absorption behavior of a beta titanium alloy in acid fluoride solutions has been analyzed by hydrogen thermal desorption. The amount of absorbed hydrogen increased with immersion time in a 2.0% acidulated phosphate fluoride (APF) solution. In the case of an immersion time of 60 h, the amount of absorbed hydrogen exceeded 10000 mass ppm. In contrast, the amount of hydrogen absorbed in the 0.2% APF solution was several times smaller than that in the 2.0% APF solution for the same immersion time. For immersion in a 0.2% APF solution, hydrogen absorption saturated after 48 h. The surface topography and corrosion products on the surface of the specimen immersed in the 2.0% APF solution were different from those in the 0.2% APF solution. During the later stage of immersion, the amount of absorbed hydrogen markedly increased under higher applied stress, although the applied stress did not enhance hydrogen absorption during the early stage of immersion. These results of hydrogen absorption behavior are consistent with the delayed fracture characteristics of the beta titanium alloy. 相似文献
943.
Rapidly prototyped temporal bone model for otological education 总被引:1,自引:0,他引:1
Suzuki M Ogawa Y Hagiwara A Yamaguchi H Ono H 《ORL; journal for oto-rhino-laryngology and its related specialties》2004,66(2):62-64
The anatomy of the temporal bone is extremely complicated. If a three-dimensional model could be simulated, it would greatly contribute to the stereoscopic understanding of anatomy and surgery. A simulated three-dimensional model of a human temporal bone was prototyped using the selective laser sintering method. The model could be shaved using a surgical drill in the same way as in real surgery. A magnified model was particularly useful for the instruction of anatomy and surgery. When a translucent area was selected, a bony labyrinth could be created together with an internal auditory meatus and facial nerve, which also contributed to the easy understanding of the inner ear structure. The three-dimensional prototyped model using selective laser sintering serves as a good educational material for middle ear anatomy and surgery. 相似文献
944.
Endothelin-1 regulates cardiac sympathetic innervation in the rodent heart by controlling nerve growth factor expression 总被引:9,自引:0,他引:9 下载免费PDF全文
Ieda M Fukuda K Hisaka Y Kimura K Kawaguchi H Fujita J Shimoda K Takeshita E Okano H Kurihara Y Kurihara H Ishida J Fukamizu A Federoff HJ Ogawa S 《The Journal of clinical investigation》2004,113(6):876-884
The cardiac sympathetic nerve plays an important role in regulating cardiac function, and nerve growth factor (NGF) contributes to its development and maintenance. However, little is known about the molecular mechanisms that regulate NGF expression and sympathetic innervation of the heart. In an effort to identify regulators of NGF in cardiomyocytes, we found that endothelin-1 specifically upregulated NGF expression in primary cultured cardiomyocytes. Endothelin-1-induced NGF augmentation was mediated by the endothelin-A receptor, Gibetagamma, PKC, the Src family, EGFR, extracellular signal-regulated kinase, p38MAPK, activator protein-1, and the CCAAT/enhancer-binding protein delta element. Either conditioned medium or coculture with endothelin-1-stimulated cardiomyocytes caused NGF-mediated PC12 cell differentiation. NGF expression, cardiac sympathetic innervation, and norepinephrine concentration were specifically reduced in endothelin-1-deficient mouse hearts, but not in angiotensinogen-deficient mice. In endothelin-1-deficient mice the sympathetic stellate ganglia exhibited excess apoptosis and displayed loss of neurons at the late embryonic stage. Furthermore, cardiac-specific overexpression of NGF in endothelin-1-deficient mice overcame the reduced sympathetic innervation and loss of stellate ganglia neurons. These findings indicate that endothelin-1 regulates NGF expression in cardiomyocytes and plays a critical role in sympathetic innervation of the heart. 相似文献
945.
Health attitudes and behaviors: comparison of Japanese and Americans of Japanese and European Ancestry 总被引:1,自引:0,他引:1
Adults living in Japan (N = 357) and the US (N = 223) completed semi-structured interviews assessing health-related attitudes and practices. The US respondents were of Japanese (N = 106) and European (N = 117) ancestry. Results indicated considerable similarity between the two US groups and significant differences between the Japanese and American respondents. The Japanese respondents placed less priority on health, had less belief in the efficacy of health screening tests, lower levels of internal health locus of control (HLOC), and higher levels of chance and powerful-others HLOC. While Japanese and Americans had similar overall levels of healthy behaviors, the Japanese were less likely to have obtained health screening tests (especially gynecologic exams). The findings have implications for adapting health promotion programs in the context of Japanese and American cultures. 相似文献
946.
Ogawa M Kubo S Uenishi T Hirohashi K Tanaka H Shuto T Yamamoto T Takemura S 《Osaka city medical journal》2004,50(2):95-99
A 64-year-old man with a 9.0 cm benign hepatic cyst near the hepatic hilum presented with obstructive jaundice caused by the compression of the hepatic ducts. The cyst was aspirated percutaneously, and minocycline hydrochloride was instilled as a sclerosant through a catheter inserted into the cyst. The cyst gradually became smaller, relieving the obstructive jaundice. There were no complications or side-effects. The instillation of minocycline hydrochloride is a useful alternative to ethanol instillation for treating benign hepatic cysts, even when the cyst is causing obstructive jaundice. 相似文献
947.
Ohashi N Mitamura H Tanimoto K Fukuda Y Kinebuchi O Kurita Y Shiroshita-Takeshita A Miyoshi S Hara M Takatsuki S Ogawa S 《Journal of cardiovascular pharmacology》2004,44(3):386-392
Calcium overload plays a key role in the development of atrial electrical remodeling. The effect of an L-type Ca channel blocker in preventing this remodeling has been reported to be short lasting, partly due to down-regulation of this channel and persisting Ca entry through the T-type Ca channel. To prove if efonidipine, a dual L- and T-type Ca channel blocker exerts a greater effect than an L-type Ca channel blocker verapamil, 21 dogs underwent rapid atrial pacing at 400 bpm for 14 days, pretreatment with efonidipine in 7 (E), verapamil in 7 (V), and none in 7 (C). We measured the atrial effective refractory period (ERP) serially during 14 days of rapid pacing. In response to rapid pacing, ERP decreased progressively in C. In contrast, in E and V, ERP remained greater than ERP in C (P < 0.01) on days 2 through 7. However, on the 14th day, ERP in V decreased to the level seen in C, whereas ERP in E remained significantly longer than ERPs in C or V (P < 0.01). The blockade L-type Ca channel alone is not sufficient, but the addition of a T-type Ca channel blockade shows a more sustained effect to prevent atrial electrical remodeling. 相似文献
948.
Watanabe O Shimizu T Imamura H Kinoshita J Utada Y Okabe T Kimura K Hirano A Aiba M Ogawa K 《Journal of surgical oncology》2004,87(2):75-79
BACKGROUND AND OBJECTIVE: The aim of this study is to know whether intravenous digital subtraction angiography (IV-DSA) is useful to detect axillary lymph node metastasis of breast cancer and to evaluate the anigiogenesis of lymph nodes in the axilla. PATIENTS AND METHODS: Forty three primary breast cancer patients (N0: 26 cases, N1: 5 cases, N2: 2 cases) who underwent IV-DSA between January and November 2000 were included in the study. Infinix CB apparatus (Toshiba, Japan) was used to collect IV-DSA images and when a mass became stained in the axilla, it was considered to be metastatic. The angiogenesis was studied by examining microvessel density (MVD) after lymph node immunostaining for factor VIII. Primary tumor was detected by IV-DSA in all 43 cases. RESULTS: Axillary lymph node metastases were detected by IV-DSA in 34.9% of cases (15/43), and by pathology in 37.2% (16/43). The sensitivity, specificity, and accuracy of the diagnostic method were 75.0% (12/16), 88.9% (24/27), and 83.7% (36/43), respectively. MVD, calculated after immunostaining for factor VIII, was significantly lower in the in metastatic region of lymph nodes identified by DSA (88.5 +/- 35.0) than in metastasis-free lymph nodes (141.1 +/- 34.0, P < 0.0001). CONCLUSIONS: IV-DSA is useful in the diagnosis of axillary lymph node metastasis of breast cancer. Our results suggest that the primary factors involved in the mechanism of DSA display may be different from high/low MVC values. 相似文献
949.
Motoyama S Okuyama M Kitamura M Saito R Kamata S Murata K Ogawa J 《Journal of surgical oncology》2004,87(1):26-31
BACKGROUND AND OBJECTIVES: A substantial body of evidence suggests that allogeneic blood transfusion increases the rate of recurrence of resected malignancies. The present study was conducted with the aim of understanding better the clinical characteristics of recurrent esophageal cancer and determining whether any survival advantage is conferred by transfusing autologous instead of allogeneic blood during the esophagectomy for the original malignancy. METHODS: We retrospectively analyzed 123 patients who received blood transfusion while undergoing esophagectomy for thoracic esophageal cancer between January 1991 and February 1998. We focused on those patients in whom the malignancy recurred. Of them, 23 patients received allogeneic blood and 18 received autologous blood. Compared were the clinico-pathological factors influencing prognosis as well as the disease-free survival periods and the period of survival after recurrence of the cancer. RESULTS: The clinico-pathological factors that influenced prognosis were similar in the two groups. There was also no significant difference in the rate at which the esophageal cancer recurred, or in survival time once it had recurred. On the other hand, disease-free survival prior to recurrence was significantly prolonged in the autologous blood transfusion group. CONCLUSION: Use of autologous instead of allogeneic blood prolongs disease-free survival of esophageal cancer patients. 相似文献
950.
Naritaka Y Ogawa K Shimakawa T Wagatsuma Y Hamaguchi K Konno S Katsube T Yagawa H Aiba M Ide H 《Anticancer research》2004,24(4):2385-2389
A 32-year-old woman was admitted to our hospital with dysphagia. An upper gastrointestinal series revealed Borrmann type 2 esophageal cancer in the lower thoracic esophagus. Because direct invasion of the thoracic aorta was suspected, FAP therapy (CDDP, 5-FU and ADM) was given as neoadjuvant chemotherapy. After completion of two courses, her dysphagia resolved and the tumor shrank by over 90%, so radical surgery was performed. No lesions were found when the resected specimen was examined macroscopically. The only histological change was hyperplasia of collagen fibers in the submucosa, lamina propria and adventitia of the esophagus. No cancer cells and no metastases to the lymph nodes were observed. Because the tumor had completely disappeared, the histological effect of chemotherapy was classified as grade 3, i.e., pathological complete response (PCR). The response to FAP therapy was excellent and no serious adverse events occurred. Therefore, this is one of the treatments that should be actively applied in patients who have advanced esophageal cancer with suspected lymph node metastasis and invasion of other organs. 相似文献