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81.
K Sawada H Yamamoto K Matsumoto H Yago S Suehiro C Tahara H Ishii M Kazama T Abe 《Thrombosis research》1992,65(2):199-209
Changes in the plasma thrombomodulin (TM) level were examined in endotoxin-infused rabbits. The plasma TM level in normal rabbits was 143.8 +/- 8.4 ng/ml (n = 67) and the molecular weight of the major TM was about 55 kd. Endotoxin (lipopolysaccharide, LPS, E. Coli B8:0127) was intravenously infused. LPS infusion increased the plasma TM level dose-dependently between 0.2 mg/kg and 5 mg/kg. When 5 mg/kg LPS was infused, the plasma TM level started to increase immediately and was 2.3 times higher than the control value within 1 hr. The molecular weight of the major TM was about 75 kd. This rapid increase in TM occurred before the decrease in fibrinogen content and the prolongation of prothrombin time. To examine the effect of circulating leukocytes on the TM increase in endotoxin-infused rabbits, 5 mg/kg LPS was infused into rabbits with leukocytopenia induced by X-ray irradiation. The maximum plasma level of TM was significantly lower than in the untreated rabbits given LPS. These data suggest that the increase in plasma TM is caused by LPS-stimulated leukocyte's prior to hemostaseological changes. It is well known that endothelial cells can be injured by stimulated leukocytes, so this increase in plasma TM probably reflects the deterioration of endothelial cells. This deterioration decreases the ability of endothelial cells to inhibit thrombosis, which would, in turn, contribute to the development of disseminated intravascular coagulation in endotoxin-infused rabbits. 相似文献
82.
Kazuhiko Nishizaki Toshio Seki Takehisa Abe 《Annals of thoracic and cardiovascular surgery》2006,12(4):293-296
This reports a case of a 68-year-old woman who had undergone coronary artery bypass 5 years previously. Magnetic resonance angiography (MRA) revealed that the ascending aorta was dilated to about 8 cm in diameter, with type A dissection, and with a patent left internal thoracic artery (LITA) graft to the left anterior descending artery (LAD). Angiography at the ascending aorta did not reveal a coronary artery, nor did it show the sequential saphenous vein graft (SVG) to the obtuse marginal and posterolateral branches. Although the risk of surgical treatment via repeat median sternotomy was very high, we successfully performed the reoperation using profound hypothermic circulatory arrest. The dissection in the mediastinum was facilitated by a sternum retractor for ITA-graft dissection, intraoperative surface echocardiography, and ultrasonic scalpel, with a widely opened bilateral pleural cavity. Furthermore, assuming that most of the myocardium was maintained by perfusion from the in-situ, patent, ITA graft, it was thought that cardioplegia was not necessary during profound hypothermic circulation. 相似文献
83.
Shinji Nakashima Masayuki Morikawa Kanshi Komatsu Akihiro Matsuura Noriyuki Sato Tomio Abe 《The Journal of heart and lung transplantation》2005,24(4):462-469
OBJECTIVE: NKH477 was recently identified as a water-soluble forskolin derivative and was reported to prolong survival of murine cardiac allografts. However, the mechanism of the efficacy is not clear in vivo. The aim of this study was to investigate the immunosuppressive effects of NKH477 on acute lung allograft rejection in the rat model and its mechanism of action in vivo. METHODS: Left lungs were transplanted orthotopically from Brown-Norway donors to Lewis recipients. Recipient rats were untreated or treated daily with different doses of NKH477. Grafts were excised on Day 3 or Day 5 to determine histopathological rejection and expressions of interleukin (IL)-2, IL-4, IL-10, and interferon (IFN)-gamma by enzyme-linked immunosorbent assay. The cytokine expression at Day 3 or Day 5 was also evaluated in recipient spleens by immunohistochemistry. Furthermore, mesenteric lymph node cells from recipients at Day 5 were cultured alone or stimulated with donor antigens for 72 hours to determine cell proliferation by means of thymidine incorporation. RESULTS: NKH477 significantly extended allograft survival time in a dose-dependent manner and reduced histopathological rejection. Treatment with NKH477 inhibited IFN-gamma and IL-10 expression, whereas expression of these cytokines were markedly upregulated in the untreated allografts. Expression of IL-2 and IL-10 also increased in the spleen of untreated allorecipients. NKH477 suppressed expression of both cytokines in the spleen. In addition, lymphocyte proliferation was inhibited in NKH477-treated recipients as compared with untreated recipients. CONCLUSION: These results suggest that NKH477 exerts an antiproliferative effect on lymphocytes in vivo with an altered cytokine profile in rat recipients of lung allografts. 相似文献
84.
Nobuyoshi Kawaharada Kiyofumi Morishita Johji Fukada Yoshikazu Hachiro Yasuaki Fujisawa Tatsuya Saito Yoshihiko Kurimoto Tomio Abe 《European journal of cardio-thoracic surgery》2005,27(4):622-625
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms. 相似文献
85.
Takashi Yamauchi Takafumi Masai Koji Takeda Satoshi Kainuma Yoshiki Sawa Kazuo Abe 《Annals of thoracic and cardiovascular surgery》2007,13(6):410-412
We report a rare case of constrictive pericarditis that stimulated a large mediastinal tumor obstructing the right ventricular inflow tract. A 58-year-old woman was referred to our hospital because of a recent increase of dyspnea and facial edema. Computed tomography revealed severely thickened calcification, including a low-density area, presenting as a mediastinal tumor, compressing the right ventricular inflow tract. A complete resection was performed, and her symptoms dramatically improved. Idiopathic constrictive pericarditis was diagnosed pathologically. 相似文献
86.
A Tsuchiya K Sekikawa Y Ando S Suzuki I Kimijima R Abe 《The Japanese journal of surgery》1990,20(5):510-514
Abnormal DNA content has been considered as an additional criterion for determining the biological behavior of a tumor. Flowcytometric DNA analysis was done on 121 patients with thyroid carcinoma encountered during the period between 1975 and 1987. Tumor tissues were sampled from paraffin-embedded blocks and the histology of thyroid carcinoma found to consist of 91 papillary, 23 follicular, 2 medullary, 1 squamous cell and 4 anaplastic carcinomas. The incidence of aneuploidy in thyroid carcinoma was 7.4 per cent (9 patients) while that of diploidy was 92.6 per cent (112 patients). The aneuploid specimens consisted of 6 papillary, 1 follicular, 1 medullary and 1 anaplastic carcinomas and, of 4 anaplastic carcinoma patients with subsequent death within 6 months, only 1 was aneuploid. As an indicator of proliferative potential, S-phase fraction (SPF) was also determined by flow cytometry, but this could not be used as an independent prognostic factor. The aneuploid patients showed a significantly decreased survival rate (p less than 0.01). Thus, although DNA measurement proved useful for predicting the survival of aneuploid patients, there is some discrepancy between DNA content and the biological behavior of the tumor. 相似文献
87.
Increased accumulation of iodine-123-IMP in the pulmonary inflammatory lesion surrounding a lung cancer 总被引:1,自引:0,他引:1
Masayuki Nakajo Noriaki Uchiyama Yoshiyuki Hiraki Yoshihiko Miyata Atsuhisa Iriki Yasunobu Hirotsu Joeji Wakimoto Yoshimasa Norimatsu 《Annals of nuclear medicine》1988,2(1):49-53
In a patient with primary lung cancer, increased accumulation of I-123-IMP was observed in a pulmonary inflammatory lesion surrounding a lung cancer which was delineated as a photon deficient area. Ga-67-citrate uptake was observed in both the inflammatory and cancerous areas. These findings suggest that I-123-IMP may have the potential to accumulate differently in a variety of pathological conditions of the lung and thus may be a clinically useful lung imaging agent. 相似文献
88.
Y. Watanabe M. Sato T. Lee Y. Abe Y. Nakata H. Kashu S. Iseki Y. Mizukami S. Kimura 《HPB surgery》1996,9(2):107-111
A 75-year-old man who was diagnosed as having mucin-producing pancreatic cystic lesion ofthe
main pancreatic duct by duodenoscopic examination was reported. Because of the low
malignant potential of such lesions, duodenum-preserving resection of the head of the pancreas
was performed, and the intra-operative histological examination showed no malig-nancy of the
resected pancreatic head and no other surgical procedures, such as lymph-adenectomy nor
pancreato-duodenectomy were necessary. The significance of this case report lies in that a less
invasive operation should be selected at first to diagnose whether the lesion is malignant or not,
and als0 that the selected operation itself must be sufficient to resect an adequate part of the
pancreatic tissue involving the cystic lesion, ifnot malignant. Here, we report the process to select
the procedure and the surgical technique. 相似文献
89.
Atsushi Yokota Munekazu Doi Hisashi Ohtsuka Muneaki Abe 《Journal of orthopaedic research》2003,21(1):36-43
To clarify how the peripheral nerve adapts to elongation during gradual limb lengthening, electrophysiological and histomorphometric examinations were performed on the sciatic nerves in 18 rabbits. External fixators were used to lengthen the right femora by 30 mm (30%), at a daily rate of 0.5 mm (Group 1) or 2.0 mm (Group 2). Examinations were performed immediately after the limb lengthening procedure. Electrophysiologically, mild conduction slowing was observed in Group 1; a conduction block was evident in Group 2. Histologically, the mean diameter of myelinated fibers was unchanged in Group 1, but a significantly decreased diameter was observed in Group 2. Electron microscopy revealed that mild degenerative change of unmyelinated axons occurred sporadically in two cases in Group 2, but neither group showed evidence of thinning of myelin sheath of myelinated fibers. The mean internodal length (between nodes of Ranvier) of teased fibers was 1216+/-295 microm in the control contralateral side, 1484+/-347 microm in Group 1, and 1467+/-322 microm in Group 2. Thus the internodes were lengthened by 22.1% (Group 1) and 20.7% (Group 2) in comparison with those of the controls. Straightening of the geometry of paranodal myelin sheath was significantly correlated with the rate of distraction. These results indicate that myelinated nerve fibers adapt to gradual elongation by lengthening each Schwann cell body, not by proliferation of Schwann cells. 相似文献
90.
We investigated the expression of adhesion molecules of lymphocyte function-associated antigen-1 alpha (LFA-1 alpha) and its ligand intercellular adhesion molecule-1 (ICAM-1) on 74 well-characterized B cell lymphomas. The LFA-1 was expressed on B cell lymphomas (21/74; 28 per cent), but to a lesser degree than ICAM-1 which was highly expressed (48/74 cases; 64 per cent). From the results of bone marrow examination of 39 cases with B cell lymphomas, 13 of 16 cases with a lack of ICAM-1 molecule showed a higher incidence of marrow involvement, but nine of 23 cases with the expression of ICAM-1 molecule showed a lower incidence. These findings suggest that the lack of expression of the ICAM-1 molecule by B cell lymphomas correlates with bone marrow involvement by lymphoma cells (p < 0.05). Expression of the LFA-1 molecule appears not to correlate with marrow involvement (p < 0.05). 相似文献