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61.
Togo S Nagano Y Masui H Tanaka K Miura Y Morioka D Endo I Sekido H Ike H Shimada H 《Hepato-gastroenterology》2005,52(63):913-919
BACKGROUND/AIMS: To determine an appropriate surgical treatment for patients with multiple liver metastases, we evaluated the efficacy of two-stage hepatectomy in patients with multiple bilobular liver metastases from colorectal carcinoma. METHODOLOGY: Some patients with multiple liver metastases are not candidates for a complete resection by a single hepatectomy, even when downstaged by chemotherapy, after portal embolization. In two-stage hepatectomy, the highest possible number of tumors is resected in a first, noncurative intervention, and the remaining tumors are resected after a period of liver regeneration. Two-stage hepatectomy was performed in 11 patients. RESULTS: Two-stage hepatectomy was feasible in all of the 11 patients. In 3 of them, the first stage was a major resection (more extensive than a lobectomy). This first hepatectomy was uneventful in all patients. The second hepatectomy was also uneventful in nine patients, but in one of the other two, a perihepatic fluid infection occurred, and in the other, postoperative liver failure developed due to a right subphrenic abscess. However, all patients were discharged. The percentage of the expected resection volume at one time, calculated from CT volumetry, was 75.5+/-1.2% and the prognostic score as surgical risk was 56.6+/-4.5. In two-stage hepatectomy cases, the percentage of the resected volume and the prognostic score in the first hepatectomy were 25.4+/-6.4% and 6.7+/-7.3, and in the second, 45.7+/-4.5% and 28.5+/-5.8. During the follow-up procedures, a residual hepatic recurrence was observed in 6 patients, and pulmonary recurrence in 9. The 1- and 3-year survival rates after the first hepatectomy were 90% and 45%, with median survivals of 18 months from the first hepatectomy. CONCLUSIONS: Two-stage hepatectomy is a surgical modality intended for patients with initial unresectable metastases. However, following such surgery, protective treatment against residual liver recurrence and lung metastasis will be a most important issue. 相似文献
62.
Takashi Tsukahara Masaru Tamura Hiromichi Yamazaki Hideyuki Kurihara Shigeru Matsuzaki 《Journal of cancer research and clinical oncology》1992,118(3):171-175
Summary The effects of -difluoromethylornithine (DFMO), radiation and the therapy of their combination were investigated in rats bearing G-XII glioma. DFMO treatment as well as radiation therapy prolonged the survival period when compared to the results in non-treated control rats. The combination therapy showed a greater effect on the survival rate than the single therapies, the effect being additive. The concentration of putrescine, spermidine, andN
1-acetylspermidine in tumor tissues was lowered by DFMO, while that of spermine was slightly elevated. Radiation decreased the concentration of all the polyamines, putrescine, spermidine, spermine andN
1-acetylspermidine. The concomitant treatment with DFMO and radiation further decreased the concentrations of putrescine andN
1-acetylspermidine in tumor tissues. The survival period of glioma-bearing rats is inversely correlated with the tissue levels of putrescine plusN
1-acetylspermidine.Abbreviations DFMO
-difluoromethylornithine
- BrdUrd
bromodeoxyuridine 相似文献
63.
Extremely early onset of ranitidine action on human histamine H2 receptors expressed in HEK293 cells
Fukushima Y Ishikawa T Saitoh T Tateishi K Ogihara T Fujishiro M Shojima N Honda M Kushiyama A Anai M Sakoda H Ono H Onishi Y Otsuka H Katagiri H Nagai R Omata M Asano T 《Digestion》2003,68(2-3):145-152
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly. 相似文献
64.
Nishi J Minamino T Miyauchi H Nojima A Tateno K Okada S Orimo M Moriya J Fong GH Sunagawa K Shibuya M Komuro I 《Circulation research》2008,103(3):261-268
Vascular endothelial growth factor (VEGF) binds both VEGF receptor-1 (VEGFR-1) and VEGF receptor-2 (VEGFR-2). Activation of VEGFR-2 is thought to play a major role in the regulation of endothelial function by VEGF. Recently, specific ligands for VEGFR-1 have been reported to have beneficial effects when used to treat ischemic diseases. However, the role of VEGFR-1 in angiogenesis is not fully understood. In this study, we showed that VEGFR-1 performs "fine tuning" of VEGF signaling to induce neovascularization. We examined the effects of retroviral vectors expressing a small interference RNA that targeted either the VEGFR-1 gene or the VEGFR-2 gene. Deletion of either VEGFR-1 or VEGFR-2 reduced the ability of endothelial cells to form capillaries. Deletion of VEGFR-1 markedly reduced endothelial cell proliferation and induced premature senescence of endothelial cells. In contrast, deletion of VEGFR-2 significantly impaired endothelial cell survival. When VEGFR-1 expression was blocked, VEGF constitutively activated Akt signals and thus induced endothelial cell senescence via a p53-dependent pathway. VEGFR-1(+/-) mice exhibited an increase of endothelial Akt activity and showed an impaired neovascularization in response to ischemia, and this impairment was ameliorated in VEGFR-1(+/-) Akt1(+/-) mice. These results suggest that VEGFR-1 plays a critical role in the maintenance of endothelial integrity by modulating the VEGF/Akt signaling pathway. 相似文献
65.
66.
Kojima H Uemura M Sakurai S Ann T Ishii Y Imazu H Yoshikawa M Ichijima K Fukui H 《Journal of gastroenterology》2002,37(8):617-625
Background:
Background: Liver disturbance in rheumatoid diseases results not only from liver disease associated with the rheumatoid diseases themselves
but also from various other causes. This study aimed to elucidate the clinical features of liver disturbance in rheumatoid
diseases, focusing on the cause of this disturbance.
Methods: A clinicopathological study was performed in 306 patients (106 with systemic lupus erythematosus, 71 with Sj?gren's syndrome,
59 with rheumatoid arthritis, 27 with scleroderma, 30 with polymyositis, and 13 with polyarteritis nodosa).
Results: Liver disturbance occurred in 43% of these patients and resulted from various causes. Its degree and duration varied from
one cause to another. Liver disease associated with rheumatoid diseases was the leading cause of the liver disturbance in
these patients and was characterized by mild and transient liver disturbance (maximum alanine aminotransferase [ALT] level
during the study period, 68 ± 8 IU/ml; maximum alkaline phosphatase [ALP] level, 410 ± 31 IU/ml; duration of liver disturbance,
6 ± 2 months). Most patients with this type of liver disease showed minimal change in liver histology, although two-thirds
of those evaluated by the international scoring system for autoimmune hepatitis (AIH) were classified as “probable” or “definite”.
Eight of 14 patients with histologically proven chronic hepatitis or cirrhosis were infected with hepatotropic virus (7 with
hepatitis C virus [HCV] and 1 with hepatitis B virus [HBV]). Five of 9 patients in whom the hepatic lesion progressed had
hepatotropic virus infection (4 with HCV and 1 with HBV), and the other 4 patients suffered from autoimmune liver diseases.
Conclusions: Liver disease associated with rheumatoid diseases was the leading cause of liver disturbance in these patients and was characterized
by mild and transient liver disturbance, whereas progressive liver diseases were often associated with hepatotropic virus,
mainly HCV, or autoimmune liver diseases. Liver histology is indispensable for differentiating AIH from liver disease associated
with rheumatoid diseases.
Received: August 27, 2001 / Accepted: January 7, 2002 相似文献
67.
Takahashi H Takeishi Y Seidler T Arimoto T Akiyama H Hozumi Y Koyama Y Shishido T Tsunoda Y Niizeki T Nozaki N Abe J Hasenfuss G Goto K Kubota I 《Circulation》2005,111(12):1510-1516
68.
69.
70.
Volume rendering (VR) is a technique commonly used for the reconstruction of three-dimensional (3D) digital subtraction angiography (DSA) images, and the rendering parameters greatly affect the characteristics of the 3D image. This study aimed to test whether the optimal VR parameters for 3D DSA could be estimated from the contrast effects in rotational two-dimensional (2D) DSA images acquired using 3D DSA. Simulated blood vessels filled with various concentrations of contrast medium were scanned, and the 3D DSA data sets were reconstructed. The syngo AX vessel analysis software that was able to analyze 3D DSA VR image was used for objective measures. Raw data projection images of the 3D DSA data sets in which the mean diameter was calculated as a true value by the software at nine different thresholds for vessel segmentation were selected. In each image set, five images of all 133 rotational 2D DSA images were selected, and the contrast-enhanced area was extracted using a region-growing algorithm. Mean values and standard deviations of each contrast-enhanced area were calculated, and as the thresholds for vessel segmentation of the software increased by 500 every time, significant differences were observed in the mean values (P < 0.01). This optimal threshold can be applied to the window settings of the VR technique. Therefore, the optimal VR parameters for 3D DSA may be determined by analyzing the contrast effects of the raw data projection images, and user-dependent over- and underestimations of 3D DSA VR images also may be prevented. 相似文献