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41.
We evaluated three solutions used for preserving lungs, namely, University of Wisconsin (UW), Euro-Collins (E-C), and low potassium dextran (LPD), by measuring the high energy phosphates in the preserved lung tissue. The left lungs of Sprague-Dawley rats were excised and flushed with 5 ml of one of the solutions at 10°C through the pulmonary artery, after which they were deflated and immersed in the solution at 10°C for 24 h. The tissue adenosine triphosphate (ATP) concentration in mol/g tissue wet weight after 24 h of storage was 2.55 ± 0.48 (n = 7) in the UW lungs, 1.98 ± 0.25 (n = 6) in the E-C lungs, and 1.53 ± 0.32 (n = 4) in the LPD lungs, being significantly higher in the UW lungs than in either the E-C or LPD lungs (P < 0.05). The histopathological findings of the E-C lungs were more deteriorated, with marked interstitial edema, septal hypertrophy, and perivascular hyaline degeneration, than either the UW or LPD lungs. Thus, the findings of this study indicate the superiority of UW solution for lung preservation. 相似文献
42.
Karube Y Katsuno K Ito S Matsunaga K Takata J Kuroki M Murakami M Matsuoka Y 《Annals of nuclear medicine》1999,13(6):407-413
The method for subtracting the initial image from the localization image was evaluated for radioimmunoscintigraphy of tumors with technetium-99m (Tc-99m) labeled antibodies. Monoclonal antibodies were parental mouse and mouse-human chimeric antibodies to carcinoembryonic antigen (CEA), designated F11-39 and ChF11-39, respectively, both of which have been found to discriminate CEA in tumor tissues from the CEA-related antigens. After reduction of the intrinsic disulfide bonds, these antibodies were labeled with Tc-99m. In vivo studies were performed on athymic nude mice bearing the human CEA-producing gastric carcinoma xenografts. Though biodistribution results showed selective and progressive accumulation of Tc-99m labeled antibodies at the tumor site, high radioactivity in blood was inappropriate for scintigraphic visualization of the tumors within a few hours. We examined the subtraction of the initial Tc-99m image from the Tc-99m localization image after a few hours. Subtracted images of the same count reflected the in vivo behavior of the Tc-99m radioactivity. The subtracted scintigrams revealed excellent tumor images with no significant extrarenal background. Visualization of the tumor site was dependent on antigen-specific binding and nonspecific exudation. These results demonstrate that a method of subtraction of the initial image may serve as a potentially useful diagnostic method for an abnormal site for agents with a low pharmacokinetic value. 相似文献
43.
Nakajima K Kinuya K Mizutani Y Hwang EH Michigishi T Tonami N Kobayashi K 《Annals of nuclear medicine》1999,13(1):5-11
Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function. 相似文献
44.
Delayed image of iodine-123 iomazenil as a relative map of benzodiazepine receptor binding: The optimal scan time 总被引:2,自引:0,他引:2
Yoshihiro Onishi Yoshiharu Yonekura Fumiko Tanaka Sadahiko Nishizawa Hidehiko Okazawa Koichi Ishizu Toru Fujita Junji Konishi Takao Mukai 《European journal of nuclear medicine and molecular imaging》1996,23(11):1491-1497
Delayed single-photon emission tomograpic (SPET) images after an intravenous bolus injection of iodine-123 iomazenil have been used as a relative map of benzodiazepine receptor binding. We determined the optimal scan time for obtaining such a map and assessed the errors of the map. SPET and blood data from six healthy volunteers and five patients were used. A three-compartment kinetic model was employed in simulation studies and analyses of actual data. The simulation studies suggested that, in the normal brain, the scan time at which a single SPET image best represented the relative receptor binding was 3.0–3.5 h post-injection. This finding was supported by actual data from the volunteers. The simulation studies also suggested that the optimal scan time was not greatly changed by the variability of the input functions, and that the error in the SPET image contrast in the vicinity of the optimal scan time was not increased by changes in the tracer kinetics in the entire brain. The SPET image contrast in the patients at 3.0 h post-injection agreed well with the reference receptor binding estimated by kinetic analysis, with a mean error of 3.6%. These findings support the use of a single SPET image after bolus injection of [123I]iomazenil as a relative map of benzodiazepine receptor binding. For this purpose, a SPET scan time of 3.0-3.5 h post-injection is recommended. 相似文献
45.
Yoshinori Ebato Yoshinori Kato Hiraku Onishi Tsuneji Nagai Yoshiharu Machida 《Drug development research》2003,58(3):253-257
A simple method for the preparation of the inner liposomes for double liposomes (DL) was developed. The encapsulation efficiency of erythrosine in liposomes prepared by this new method is superior to that of the previous method because of the concentration of the drug in the lipid membrane. To evaluate the usefulness of DL prepared by the glass‐filter method modified in this study as an oral dosage form of salmon calcitonin (SCT), a suspension of liposomes containing SCT was administered to rats at a dose of 10 μg SCT/kg. Each type of DL showed better efficacy than its inner liposomes alone. The decrease in plasma calcium level was dependent on the electrical charge and particle size of the inner liposomes. The hypocalcemic efficacy of DL encapsulating SCT‐loading cationic liposomes relative to that after subcutaneous administration of SCT at a dose of 1 μg/kg was 6.47%, which was the largest value obtained. These results indicated that not only the particle size but also the electrical charge of inner liposomes affect intestinal absorption. This study verified that the efficacy was increased because of the decrease in diameter of the inner liposomes and the use of lipid with a positive charge. These findings concluded that DL might be useful as an oral dosage form of SCT. Drug Dev. Res. 58:253–257, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
46.
Yoshihito Yokoyama M.D. Hidetoshi Maruyama M.D. Shigemi Sato M.D. Yoshiharu Saito M.D. 《Gynecologic oncology》1997,64(3):411-417
The purposes of this study were to analyze the relationship between retroperitoneal lymph node (RLN) metastasis and clinical and pathologic risk factors in endometrial cancers, and to clarify the correlation between RLN metastasis and survival of patients with the disease. This analysis included 63 patients with endometrial cancer who underwent simultaneous pelvic lymph node (PLN) and paraaortic lymph node (PAN) dissection between April 1988 and December 1995. Patients with stage Ia grade 1 and stage IV disease were excluded from this analysis. Both PLN and PAN metastases were found in 10.0% (4/40) of patients with stage I (FIGO, 1988) disease. Of 14 cases with PLN metastases, 8 (57.1%) had PAN metastases simultaneously, whereas 4 (8.2%) of 49 cases without PLN metastases had PAN metastases. There was no significant relationship between the sites or numbers of positive PLN and PAN metastases. Multivariate analysis revealed that poor grade and deep myometrial invasion had an independent relationship with PAN metastases, whereas vascular space invasion and cervical invasion were independently associated with PLN metastases. When divided into the groups of stage I–II and stage III, the prognosis of patients with RLN metastases was significantly poorer than that of patients without RLN metastases in each stage. Furthermore, survival of patients with PAN metastases was significantly worse compared with that of patients with only PLN metastases (44.4 and 80.0%, respectively,P< 0.05). These results reveal that PLN and PAN metastases occur frequently even in early-stage endometrial cancer, and that RLN metastases, especially PAN metastases, have a serious impact on patient survival. In conclusion, systemically simultaneous pelvic and paraaortic lymphadenectomy is essential for all the patients with endometrial cancer except those with stage Ia grade 1 and stage IV to provide prognostic information and select suitable postoperative treatment as well as to perform accurate FIGO staging, provided the condition of the patient permits. 相似文献
47.
Yoshihito Yokoyama M.D. Morio Sagara M.D. Shigemi Sato M.D. Yoshiharu Saito M.D. 《Gynecologic oncology》1998,68(3):280-287
Objective.To examine the relationship between the expressions of glutathioneS-transferase π (GST-π) and four oncogene products, c-Jun, c-Fos, c-H-Ras, and c-Myc, and clinicopathological prognostic factors and patients' prognosis in endometrial carcinomas, and to assess their prognostic value in endometrial carcinomas.Methods.Specimens of endometrial carcinoma obtained from 63 patients were investigated immunohistochemically using respective specific antibodies.Results.The overall positive rates in 63 carcinoma specimens were 34.9% for GST-π, 44.4% for c-Jun, 34.9% for c-Fos, 47.6% for c-H-Ras, and 54.0% for c-Myc. Multivariate analysis revealed that GST-π expression correlated independently with paraaortic lymph node (PAN) metastasis, and c-Jun expression was independently related to pelvic lymph node (PLN) and PAN metastasis. The prognosis of patients with a GST-π-positive tumor was significantly poorer than that of those with a GST-π-negative tumor (P< 0.05). The patients with c-Jun-positive tumor also had a significantly worse prognosis than those with c-Jun-negative tumor (P< 0.05). No significant relationship between the expressions of the remaining three oncogene products, c-Fos, c-H-Ras, and c-Myc, and the examined prognostic factors and clinical outcome was apparent.Conclusion.These results suggest that the expressions of GST-π and c-Jun may reflect the metastatic potential of endometrial carcinomas and that their expressions of endometrial carcinoma may be useful as a prognostic indicator for predictive testing. 相似文献
48.
49.
Nobuaki Hoshino Kenji Kawada Koya Hida Saori Goto Ryuji Uozumi Suguru Hasegawa Kenichi Sugihara Yoshiharu Sakai 《Medical oncology (Northwood, London, England)》2017,34(8):138
One of the reasons for the underuse of adjuvant chemotherapy in elderly patients with stage III colorectal cancer is a small survival benefit. This retrospective study sought to identify the predictive factors for elderly patients who could obtain a sufficient survival benefit. We reviewed the data of 1354 elderly patients (aged ≥70 years) with stage III colorectal cancer who underwent complete resection between January 1997 and December 2006. The efficacy of adjuvant chemotherapy was assessed, and the risk factors for recurrence were determined. The efficacy of adjuvant chemotherapy was also assessed after stratification for the above-mentioned risk factors for recurrence. There was a tendency for adjuvant chemotherapy to be effective in elderly patients (hazard ratio 0.84; 95% CI 0.70–1.01). Age, tumor location, pathology findings, tumor depth, venous invasion and lymph node metastasis were identified to be independent risk factors for recurrence by univariate and multivariate analyses. Among these factors, adjuvant chemotherapy was much effective in the elderly patients with high venous invasion (v2-3) (hazard ratio 0.69; 95% CI 0.52–0.91). High venous invasion (v2-3) was identified to be a predictive factor for elderly patients with stage III colorectal cancer who gained a sufficient survival benefit. 相似文献
50.
Masahide?EbiEmail author Shoko?Nakagawa Yoshiharu?Yamaguchi Yasuhiro?Tamura Shinya?Izawa Yasutaka?Hijikata Takaya?Shimura Yasushi?Funaki Naotaka?Ogasawara Makoto?Sasaki Takashi?Joh Kunio?Kasugai 《International journal of colorectal disease》2018,33(12):1703-1708