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61.
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
62.
Kazutoshi Hori Kunio Uematsu Hitoshi Yasoshima Aklhiko Yamada Kazunari Sakurai Munehiko Ohya 《Pathology international》1997,47(9):592-599
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma. 相似文献
63.
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
64.
T Tokunaga M Shigemori M Katayama S Kuramoto H Hayashi K Yamada K Nonaka Y Sasaguri 《No shinkei geka. Neurological surgery》1990,18(2):183-188
Lymphocytic adenohypophysitis is considered to be an inflammatory disease of the adenohypophysis that is commonly present with visual disturbance and hypopituitarism. Its etiology remains unclear but it is often related to an autoimmune disorder involving other organs, such as the thyroid, parathyroid, or adrenal glands. We encountered a rare case of lymphocytic adenohypophysitis associated with sarcoidosis of the lung and eye during the follow-up period. A 23-year-old woman was hospitalized in July 1986, with a one-month history of headache and visual disturbances which began three days after her second normal delivery. On admission, she showed slight visual impairment and had a left temporal superior quadrantanopia. Endocrinological evaluation revealed thyroid and adrenal hypofunction, and low response of human growth hormone to the loading test. A skull X-ray showed normal shaped sella with some erosion of the dorsum. CT scan showed a rounded contrast-enhanced intrasellar mass extending into the suprasellar cistern. MRI (SR: 500/30) showed a homogeneous low intensity mass which contained a small high intensity area on the relative T2-weighted image (2000/50). A biopsy was performed via right frontotemporal craniotomy. The consistency of the resected tissue was firmer than that of pituitary adenoma. Histologically, the tissue showed diffuse lymphocytic infiltration with some normal adenohypophysis. Her postoperative course was uneventful and the visual impairment improved two months later after the operation. Six months after the operation, she was readmitted with complaints of general fatigue and breathlessness. Chest X-ray showed diffuse infiltration throughout both lung fields, but there was no bilateral hilar lymphadenopathy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
Accommodative intraocular lens with spring action. Part 1. Design and placement in an excised animal eye 总被引:2,自引:0,他引:2
We designed an intraocular lens (IOL) with spring action, which we call the Spring IOL, with the idea of providing a slight but adequate accommodative power. The Spring IOL consists of two 6.0-mm optics, held 4.38 mm apart, and four flexible loops. The optics are made of polymethylmethacrylate (PMMA) and the loops of polyvinylidene fluoride. The lens's refractive power is provided by the anterior optic; the posterior optic acts as a footplate to restrict the anteroposterior movement of the anterior optic. By torsionally compressing the obliquely arranged loops, a 10.0-mm 3-dimensional IOL can be reduced to 6.0 mm and inserted in the capsular bag through a 3.5-mm capsular opening. Because the Spring IOL is made of the same materials as conventional IOLs, most of the problems hindering the development of a refilling material (which could also provide accommodation) are avoided. In this first report we discuss the design of the lens, the refractive theory involved, and our experience inserting it in an excised animal eye. 相似文献
66.
J Iemura T Yamada M Ueda F Ando H Suzuki 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(11):908-911
A 67-year-old man with positive serum reaction for syphilis had been followed by cardiologist for his moderate-sized saccular ascending aortic aneurysm and small-sized abdominal aortic aneurysm. Because of his transient ischemic attack probably secondary to the thrombo-embolism of the aneurysm and rapid growing of its size, surgical treatment was recommended. Resection of the saccular aneurysm with patch plasty of the ascending aorta was performed under the cardiopulmonary bypass associated with right side cerebral perfusion. At the time of operation, the mildly dilated ascending aorta and arch with multiple intimal ulceration were noted. Although his postoperative hemodynamic condition was stable, he suffered from multiple cerebral infarction, probably due to embolism migrated from the fragile aortic intima. His neurological condition was improved promptly, trivial hemi-paralysis was remained. The specimen of resected aneurysmal wall revealed syphilitic changes microscopically. We concluded that the extent of the aortic replacement with prosthetic graft should be deceived not only with its external appearance, but also with the changes of its inside. 相似文献
67.
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
68.
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
69.
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
70.
In the medical field, Korotkoff sounds have been explained as sounds generated by the disturbed blood flow in the artery. However, in the biomechanics field, Korotkoff sounds are considered to be produced and/or modified by the self-excited oscillation of a collapsed artery. The self-excited oscillation is an oscillation of the arterial wall. In addition, it is influenced by the nonlinear pressure–flow relationships in the artery and the arterial compliance. In this paper, we proposed an arterial-compliance-measuring method, using Korotkoff sounds. We constructed a circulatory simulator with a brachial model that mimics the physiological circulation, because in vivo resolution of nonlinear pressure–flow relationships is very difficult. The simulator was utilized to generate artificial Korotkoff sounds similar to those in auscultation in the brachial model. Additionally, we prepared latex tubes as artificial brachial arteries. In the experiment, we investigated the relationship between the self-excited oscillation and Korotkoff sounds by the distinguishing its frequency characteristics. The frequency of the sounds was changed by the variation of the tube compliance. As a result, we have found that the changes of the sounds largely depended on the difference of the tube compliance in this simulator. In conclusion, Korotkoff sounds contain useful information for predicting brachial arterial compliance. These experiments indicate the effectiveness of noninvasive measurement for brachial arterial compliance using Korotkoff sounds. 相似文献