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101.
Nakahara T Togawa T Nagata M Kikuchi K Hatano K Yui N Kubo A 《Annals of nuclear medicine》2003,17(7):583-591
The aims of this study were to compare the results of thallium-201 (Tl-201) SPECT, barium swallow and CT in the assessment of the effect of preoperative chemoradiotherapy. This study consisted of 28 patients with advanced esophageal squamous cell carcinoma (AESCC) who underwent the three imaging modalities before and after preoperative chemoradiotherapy. The results were quantified using the bidimensional method for barium swallow and contrast-enhanced CT and the tumor-to-lung ratio for SPECT. The percent decrease in these quantitative values after therapy was defined as %Dba, %Dct and %Dtl respectively. The histological effect of the chemoradiotherapy was determined from the resected surgical specimen of the esophagus: grade 0, 100% viable tumor cells; grade 1a, 99-67%; grade 1b, 66-34%; grade 2, 33-1%; grade 3, no viable cells. A statistically significant difference of %Dtl between the subgroups of each grade was evident (p = 0.0433), whereas no significant differences were evident for %Dba (p = 0.1778) or %Dct (p = 0.7377). However, the overlap of %Dtl between these groups was marked. Although thallium-201 SPECT cannot be used to evaluate the therapeutic effect with acceptable accuracy, SPECT may be of additional value to barium swallow and CT in assessing the response of AESCC to preoperative chemoradiotherapy. 相似文献
102.
Murakami M Tono T Imazato M Takemoto H Asaoka T Okada K Kanoh T Iwazawa T Ohnishi T Nakano Y Yano H Kinuta M Okamura J Monden T 《Gan to kagaku ryoho. Cancer & chemotherapy》2003,30(11):1665-1668
A 38-year-old man had multiple recurrence of hepatocellular carcinoma (HCC) with portal vein thrombosis after hepatectomy and postoperative transcatheter arterial chemotherapy with 5-fluorouracil (5-FU). He was treated by trans hepatic arterial embolization (TAE) with 100 mg of cisplatin (CDDP) and degrable starch microspheres (DSM). After 3 courses were administered, the recurrent lesions almost disappeared on CT, and the postoperative rise in PIVKA-II level and AFP level normalized. There were no side effects except slight fever and general fatigue. We recognized a partial response, and the patient is still alive 14 months after hepatectomy. This case suggests that TAE with CDDP and DSM might be useful for prolonging the survival of advanced HCC patients. 相似文献
103.
A self-regulated degradation system using polyion complexation through oxidation reaction from degradation products was preliminarily studied. 1,4-Dihydronicotinamide-modified dextran (NAH-Dex) with different molecular weights was prepared, and NAH moiety in NAH-Dex was oxidized by H2O2 to the dehydrated form (NA+-Dex). The dependence of stoichiometry, concentration, and molecular weight on polyion complexation with carboxymethyl dextran (CMD) were examined. NA+-Dex with a molecular weight above 40000 formed an insoluble complex with CMD, and the complexation was found to proceed stoichiometrically. The extent of polyion complexation was dependent on the concentration of NA+-Dex and CMD, whereas the time to reach complexation was dependent on H2O2 concentration. When H2O2 and dextranase were added to the solution containing NAH-Dex, CMD, and dextran, transmittance dropped and then increased again. From these results, the addition of dextran into the system of H2O2, NAH-Dex, CMD, and dextranase can regulate formation and dissociation of the polyion complex between NA+-Dex and CMD. The antagonistical inhibition of the degradation of the polyion complex is a key parameter of the self-regulated degradation system. 相似文献
104.
K Yui 《Nihon shinkei seishin yakurigaku zasshi》1999,19(3):101-110
The treatment of schizophrenic patients who fail adequate trials of typical neuroleptics is a major challenge. For these patients, the availability of atypical antipsychotics is a useful therapeutic advance. Olanzapine shows a superior and broader spectrum of efficacy in the treatment of schizophrenia, particularly its negative symptoms, with a substantially more favorable safety profile than conventional antipsychotic agents (e.g., haloperidol). However, little information on the clinical effects of olanzapine is available in Japan. This article provides information on the efficacy of olanzapine for various symptoms of schizophrenic patients and drug safety. Olanzapine is significantly superior to haloperidol in positive, negative, and depressive symptoms of patients, and for tardive dyskinesia and extrapyramidal symptoms. Significantly greater improvement in avolition-apathy is achieved with olanzapine as compared to risperidone. These advantages are related to high affinity at the 5-HT2 binding site, no association with an alteration in dopamine A9 firing rates, and lower D2 striatal receptor blockade of olanzapine. Treatment with 10 mg/day olanzapine is more appropriate for positive symptoms, and 12.5-17.5 mg/day olanzapine is more effective for negative symptoms. Patients will need help adapting to a new level of functioning after a successful switch to olanzapine, and overcoming the disappointment that eventually occurs when the limitations of olanzapine become apparent. 相似文献
105.
K Iwasaki Y Komuro N Masumoto K Asaoka K Ishitani 《Gan to kagaku ryoho. Cancer & chemotherapy》1999,26(10):1483-1486
We report a case of stage IV ovarian clear cell adenocarcinoma successfully controlled by a combination of cisplatin-cyclophosphamide (CP) and paclitaxel-carboplatin (TJ). A 64-year-old female with advanced ovarian cancer and pleural effusion underwent 4 courses of combination chemotherapy with CP. The giant ovarian tumor showed a relative reduction in size and the pleural effusion disappeared. Serum CA-125 levels and CA 19-9 levels markedly decreased. Thus, the patient underwent a total hysterectomy and bilateral salphingoophorectomy. During the operation, a giant ovarian clear cell adenocarcinoma was found, but there was no peritoneal dissemination and no cancer cells in her peritoneal fluid. Thereafter, she underwent 3 courses of combination chemotherapy with TJ. She has had 13 months of stable, tumor-free survival since the operation and normal serum CA-125 and CA 19-9 levels. Ovarian clear cell adenocarcinoma generally responds poorly to cisplatin and carboplatin, but in combination chemotherapy with paclitaxel-carboplatin these may be effective. 相似文献
106.
107.
Michael Li M.D Hester Yui Shan CHEUNG M.D Cliff Chi Chiu CHUNG M.D 《Asian journal of endoscopic surgery》2008,1(1):15-20
Laparoscopic colorectal surgery in Asia has gone a long way since 1992. In this article, the authors attempted to unfold the history of laparoscopic colorectal surgery in Asia, and report on the latest development. It is concluded that laparoscopic colorectal surgery will continue to flourish in Asia, and we will be entering a new era of endo‐laparoscopic surgery and robotic assisted laparoscopic surgery. 相似文献
108.
Transient and residual stress in a porcelain-metal strip 总被引:2,自引:0,他引:2
Porcelain-fused-to-metal (PFM) restorations may develop cracks during processing or in-mouth service if the relative physico-mechanical properties of the porcelain and metal are highly mismatched. Precise conditions when this might occur are not known. Many processing and property variations can affect the stresses developed throughout a porcelain-metal system. To understand this, we conducted a computer simulation of stress developed in a PFM beam. The simulation considers cooling from temperatures higher than the porcelain sagpoint. The following temperature-dependent factors were incorporated: the elastic modulus, shear viscosity (porcelain), and coefficients of thermal expansion. The cooling rate dependencies of the glass transition temperature, (Tg), and the temperature distribution during cooling were also included. The results suggest that transient tensile stress at the porcelain alloy interface may result in cracks in the porcelain during cooling. Occlusal forces may set up stresses to cause cracking at the surface of the porcelain if the compressive residual stress is not high enough. PFM restorations with an alloy of high thermal expansion coefficient require rapid cooling; on the contrary, PFM restorations with the alloys of lower coefficients require slow cooling. A high cooling rate can make up for thermal expansion mismatches between the alloy and the porcelain up to 2 x 10(-6)/degrees C. Finally, the results indicated that curvature was not a sensitive indication of stress for a multimaterial beam when visco-elastic relaxation and high cooling rates are involved. For the case modeled here, curvature varied inversely with a 1/2 to 1/7th power of the stress. 相似文献
109.
Origin and selection of peripheral CD4-CD8- T cells bearing alpha/beta T cell antigen receptors in autoimmune gld mice 总被引:1,自引:0,他引:1
S Wadsworth K Yui R M Siegel D E Tenenholz J A Hirsch M I Greene 《European journal of immunology》1990,20(4):723-730
We have analyzed the origin and development of unusual CD4-CD8- alpha/beta T cell receptor-positive peripheral T cells produced in large numbers by mice homozygous for the gld mutation (C3H-gld/gld). These mice may be an important model for investigating processes controlling T cell development. Bone marrow transfers demonstrated that the gld defect was intrinsic to bone marrow-derived cells. Clonal deletion of potentially autoreactive cells was observed in peripheral gld CD4-CD8-, CD4+CD8-, and CD4-CD8+ T cells, as well as mature thymocytes. This suggests that gld CD4-CD8- T cells have passed through the thymus in ontogeny and that gld autoimmunity does not result from a general defect in elimination of self-reactive thymocytes. These observations, combined with demethylation of the CD8 gene in the CD4-CD8- population, support prior expression of CD4 and/or CD8 in gld CD4-CD8- T cell ontogeny, perhaps at a CD4+CD8+ stage. Steroid sensitivity of gld thymocytes and CD4-CD8- T cells was normal. Therefore, we found no gross abnormalities in two major mechanisms of inducible cell death in the gld thymus, the clonal deletion process associated with tolerance and the steroid-inducible endogenous endonuclease thought to be involved in apoptosis of unselected thymocytes. The data suggest that if gld CD4-CD8- T cells arise via escape from normal elimination in the thymus, they must do so by a novel defect in thymic selection (perhaps related to aberrant positive signals) and/or are expanded by an extrathymic process which allows clonal deletion to occur. 相似文献
110.
S Suzuki M Saito N Suzuki H Kato N Nagaoka S Yoshitake H Mizuo T Yuzuriha Y Yui C Kawai 《Journal of cardiovascular pharmacology》1991,17(5):738-746
The thrombolytic properties of a novel modified human tissue plasminogen activator (E6010), in which cystein 84 in the epidermal growth factor domain is replaced by serine and that has a prolonged biological half-life, were examined. The thrombolytic efficacies of E6010 and recombinant human tissue plasminogen activator (rt-PA) on the duration of coronary artery thrombus were evaluated in a canine model (123 anesthetized dogs) with copper coil-induced left anterior descending coronary artery thrombus. Thrombi established for periods of 1, 3, or 6 h, as documented by coronary arteriography, were employed. A single bolus i.v. injection of E6010 or rt-PA and an i.v. infusion of rt-PA over 60 min were compared (n = 6). Thrombolytic efficacy was evaluated by three criteria: time to reperfusion (TR), reperfusion rate at 60 min (RR), and reocclusion rate at 60 min after reperfusion (OR). With a bolus i.v. injection of E6010 at a dose of 0.2 mg/kg or an i.v. infusion of rt-PA at a dose of 0.6 mg/kg/h, these parameters were as follows: TR, 30.0 +/- 15.3 and 27.5 +/- 4.8 min; RR, 100 and 100%; OR, 17 and 33% for 1-h aged thrombi; TR, 30.0 +/- 9.5 and 35.0 +/- 8.2 min; RR, 83 and 50%; OR, 20 and 67% for 6-h aged thrombi. These data indicate that a bolus injection of E6010 is almost equally efficacious in lysing thrombi aged both 1 and 6 h. On the other hand, in the case of rt-PA, the thrombi aged 6 h were lysed significantly less than the thrombi aged 1 h. Plasma half-lives of E6010 were t1/2 alpha, 4.8 +/- 0.95 (estimated by antigen level) and 3.0 +/- 0.78 min (estimated by activity), and t1/2 beta, 51 +/- 5.4 (antigen level) and 22 +/- 7.0 min (activity). The half-lives of rt-PA were t1/2 alpha, 3.6 +/- 0.23 (antigen level) and 2.1 +/- 0.61 min (activity), and t1/2 beta, 36 +/- 2.3 (antigen level) and 7.0 +/- 3.5 min (activity). We conclude that a bolus injection of E6010 may have a more potent and longer-lasting effect than i.v.-infused rt-PA in clot lysis therapy. 相似文献