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51.
Yuko Takeyama Keiki Ogino Hiroyuki Segawa Haruo Kobayashi Taizo Uda Tatsuya Houbara 《Basic & clinical pharmacology & toxicology》1995,76(1):50-55
Abstract: The effects of zinc on the production of active oxygen species were investigated in rat neutrophils by chemilumi-nescence and spectrophotometric assays. The luminol-dependent chemiluminescence in unstimulated neutrophils showed a single peak. Zinc at concentrations lower than 0.1 mM augmented the intensity of chemiluminescence and showed a bimodal pattern, the first peak of which was inhibited by superoxide dismutase and catalase, while the second peak disappeared in the presence of catalase, but was unaffected by superoxide dismutase. At the same concentrations of zinc, O2? and H2O2 production increased, but secretion and activity of myeloperoxidase were not affected. Zinc at 0.1 mM enhanced the second peak of luminol-dependent chemiluminescence, and concomitantly O2? and H2O2 production of neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine. Homogenized neutrophils showed a bimodal pattern on induction by zinc, the second peak of which was inhibited slightly by catalase and completely by sodium azide, but was not inhibited by superoxide dismutase. Zinc-induced O2? production was inhibited by pertussis toxin, but was not significantly inhibited by a protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), or a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). These results suggest that zinc can augment luminol-dependent chemiluminescence by increasing O2? production through the classical signal transduction pathway, and by increasing H2O2 not via O2?. 相似文献
52.
Kentaro Yamashita Hiroyuki Tsukuda Yasuyo Mizukami Jun Ito Shigeo Ikuta Yoshihiro Kondo Hiroshi Kinoshita Yasunori Fujisawa Kohzoh Imai 《Journal of gastroenterology》1997,32(5):684-688
A case of hepatic infarction with portal thrombosis is reported. A 63-year-old woman with liver cirrhosis and esophageal varices
was admitted for treatment of the esophagel varices. Endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy
(EIS) were performed. Two months later, she experienced right hypochondralgia and right flank pain. Serum transaminase levels
were suddenly elevated, and computed tomography scans of the liver showed multiple small nodular lesions. Her condition worsened,
and she died of hepatic failure. Autopsy revealed splenic and portal vein thrombosis, multiple hepatic infarction, and evidence
of chronic pancreatitis. We believe that liver cirrhosis and chronic pancreatitis were the main risk factors for the portal
thrombosis, and the treatment for esophageal varices appeared to have triggered the thrombosis. The hepatic infarction was
caused by the portal thrombosis. 相似文献
53.
Tsutomu Saito Hiroyuki Horimi Tsuguo Hasegawa Toshiro Kamoshida 《Surgery today》1993,23(12):1081-1084
We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause. 相似文献
54.
In the liver ischemia-reperfusion model, the lipid peroxide level increased during ischemic periods, while a greater increase was observed during reflow periods. The increase in the cytochrome b5 content was observed during ischemia and reflow periods. On the contrary, the cytochrome P-450 content remained unchanged during ischemic periods, but decreased during reflow periods. Bifemelane suppressed the elevation of the lipid peroxide level, the cytochrome b5 content and the decrease in cytochrome P-450 content during the period of reperfusion. 相似文献
55.
K Nagai H Hiyoshi J S Liu H Okitsu N Hayashi R Amemiya K Oho Y Hayata 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(2):222-226
A total of 26 lung cancer cases accompanied by pleural dissemination were resected between June 1977 and June 1988. Of these 16 cases were male and 10 cases were female. Their age was 34-78, and the average age was 56.7 years. The histologic type was adenocarcinoma in 23 cases, 1 was large cell carcinoma, 1 was combined adenosquamous cell carcinoma, and 1 was combined adeno-small cell carcinoma. Of these 23 adenocarcinoma cases, 15 were well differentiated, 7 were moderately differentiated, and 1 was poorly differentiated. There was no correlation between tumor size and pleural dissemination. Pleural effusion was observed in 8, 5 had bloody effusion and the other 3 had yellow effusion. Exact preoperative diagnosis and evaluation of extent was very difficult in pleural dissemination cases except for the pleural effusion cases. Concerning the operation method in these cases pleuropneumonectomy was performed in 10, pleurolobectomy in 6, and lobectomy in 10. Prognosis of cases of resected pleural dissemination was very poor. The median survival time was 16 months, The 1-year survival rate was 56.3%, the 2-year survival rate was 23.2%, the 3-year survival rate was 15.4%, and the 4-year survival rate was 7.7%. There was no 5-year survivor in lung cancer cases of this group. Malignant pleural effusion cases had a poorer prognosis, with 6 of 8 cases dying within 1 year from operation. No remarkable therapeutic effects were achieved by adjuvant chemotherapy. In the single case of preoperative hyperthermia, histological therapeutic effect (Ef 2) was recognized. These results suggest that there is no indication of operation in malignant pleural effusion cases.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
56.
Statistical evaluation of determinants of progression of superficial bladder cancer by proportional hazards model 总被引:2,自引:0,他引:2
M Takashi T Sakata T Murase Y Takagi T Nagai M Sahashi T Shimoji K Miyake N Hamajima 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(1):116-121
To evaluate clinical and pathological factors present at the initial consultation which affect disease progression, we reviewed data from 223 patients with superficial bladder cancer (pTa and pT1) who were initially treated at Nagoya University Hospital between January 1973 and December 1987. The factors included in the present analysis were age, sex, symptoms, interval between initial symptoms and first consultation, location of tumor, size, number, endoscopic shape, histological pattern of growth, grade and stage. The median duration of the follow-up after initial treatment was 46 months. Of the 223 patients, 17 died: 8 (3.6%) of bladder cancer and the remaining 9 (4.0%) of unrelated causes. Disease progression developed in 12 patients (5.4%): muscle invasion of the bladder wall in 11 and lung metastasis in one. The interval between initial treatment and progression ranged from 4 to 108 months, with a median of 11.5 months. Of the 12 patients, 9 (75%) had disease progression within 2 years. Progression was significantly associated with poor prognosis (p less than 0.001): the 5-year actuarial survival rates were 47.1% and 92.8% in patients with and without progression, respectively. Univariate analysis by Cox's proportional hazards model demonstrated that characteristics such as irritative bladder symptoms, higher-grade tumors, invasion into lamina propria, and nonpapillary growth seen at initial consultation were significantly related to disease progression. Cox's proportional hazards model produced hazard ratios of 10.2 in irritative bladder symptoms (yes vs. no), 6.3 in histological grade (grade 3 vs. grades 0-2), 4.9 in stage (pT1 vs. pTa), and 4.7 in pattern of growth (papillary vs. nonpapillary).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
Hiroyuki Ishizu Masatoshi Takahashi Yukifumi Kondo Akihiko Kataoka Takashi Nakamura Kuniaki Okada Hiroyuki Masuko Yasunori Nishida Hideaki Ogawa Ryoji Yokoyama Yutaka Kimura 《Surgery today》1997,27(3):285-287
Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyroluspreserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system. 相似文献
58.
Japan Pancreatoduodenectomy Study Group Ryo Hosotani Masafumi Kogire Tadahiro Takada Hiroyuki Kato Takahiko Funabiki Masumasa Horisawa Takeshi Morimoto Takukazu Nagakawa Toshimichi Nakayama Itsuo Miyazaki Masayuki Imamura 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):295-303
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity
the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy
(JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery,
and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning
tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion;
the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection
was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic
resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant
tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative
resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic
factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection
with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor.
This study was carried out as a group project. The authors' institutions are as follows 相似文献
59.
OBJECTIVE: The aim of this investigation was to establish the association between left-sided gallbladders and right-sided round ligaments. SUMMARY BACKGROUND DATA: The left-sided gallbladder is a rare anomaly and has been classified into two types: 1) gallbladder migration to the left side and 2) development of a second gallbladder with atrophy of the original one. Recently, left-sided gallbladders were reported to be associated with right-sided round ligaments. METHODS: The authors reviewed 3 patients treated in their departments and 15 patients reported in the literature diagnosed as having left-sided gallbladders accompanied by right-sided round ligaments. RESULTS: Although the gallbladders of all 18 patients were located at the normal site, they were diagnosed as being left sided because of the right-sided round ligaments. This anomaly was accompanied by abnormal intrahepatic portal venous branching, which could be classified into two types. In eight patients, the first branch of the portal vein ran to the posterior segment and then the portal vein formed a trunk of the left and right anterior portal veins. The latter portal vein formed the umbilical portion and finally joined the right-sided round ligament (trifurcation type). In five, the portal vein diverged normally to form the left and right portal veins, then the latter branched to form the anterior and posterior segments, and finally the anterior branch joined the round ligament (bifurcation type). In the other five, the branching type could not be determined. CONCLUSIONS: A right-sided round ligament causes a gallbladder at the normal site to be located on the left side. This anomaly should not be diagnosed as a left-sided gallbladder but as a right-sided round ligament. Recognition of this anomaly clinically is important when performing hepatectomy, because it is always associated with abnormal intrahepatic portal venous branching. 相似文献
60.
Iwao Fukui Kazunori Kihara Hideaki Sekine Yuichi Tachibana Tsuneo Kawai Daisuke Ishiwata Hiroyuki Oshima 《Cancer chemotherapy and pharmacology》1992,30(Z1):S37-S40
Between November 1986 and April 1989, 101 patients with superficial bladder cancer were treated with intravesical instillations of mitomycin C on day 1 and doxorubicin on day 2 of each week for 5 consecutive weeks. Of 61 complete responders, 23 patients with carcinoma in situ and 28 with papillary cancer were randomly assigned to a non-maintenance group or to a group receiving maintenance therapy consisting of monthly instillations of the same drugs for 12 months. The 2-year non-recurrence rate calculated for patients with carcinoma in situ was significantly better in the maintenance group than in the non-maintenance group. A similar tendency was observed for patients with papillary cancer, although the difference was not significant. Side effects were considerable, with moderate to severe bladder irritation occurring in approximately half of the patients. In addition to our previous findings, the present results indicate that this intravesical combination chemotherapy is effective in eliminating superficial bladder cancers and that since the effect is not durable, even in complete responders, maintenance therapy is necessary to reduce subsequent tumor recurrence.Presented at the 4th International Conference on Treatment of Urinary Tract Tumors with Adriamycin/Farmorubicin, 16–17 November 1990, Osaka, Japan 相似文献