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71.
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
72.
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
73.
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
74.
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
75.
P. Lekic D. Kenny H. K. Moe E. Barrettt C. A. G. McCulloch 《Journal of periodontal research》1996,31(4):294-300
The survival rate of avulsed permanent teeth following replantation is affected primarily by the duration of the extra-alveolar period and the nature of the storage conditions. These factors are believed to strongly affect the viability of periodontal ligament (PL) cells but in vitro assays of cell viability based on vital dye assays are only weakly correlated with the tooth survival rate after replantation. The aim of the present study was to examine the relative dependence of cell membrane integrity, attachment and clonogenic capacity of human PL cells on the temperature and duration of the extra-alveolar period and the type of storage medium. Twenty-four premolar teeth were extracted for orthodontic reasons from 9 patients 11–18 years of age. Teeth were maintained at 4°C or 23°C for 15, 30, 60 or 120 min in either milk or dry conditions. Cell membrane integrity was determined by BCECF/AM dye inclusion. Plating efficiency was determined by measurement of cell attachment at 3 and 6 h. The clonogenic capacity of progenitor cells was estimated by limiting dilution and colony counts. For all assays teeth stored in milk at 4°C showed the highest percentages of BCECF positive, attached cells with clonogenic capacity. Increased storage time (15–120 min) was associated with a 50% relative reduction of BCECF staining and a 5-fold relative reduction of cell attachment regardless of storage conditions. However, the clonogenic capacity of progenitor cells decreased 25-fold over the same duration of storage. These data demonstrate that in vitro assays of clonogenic capacity are much more sensitive to extra-oral storage time and storage conditions than dye inclusion or cell attachment. We suggest that in comparison with in vitro measures of cell membrane integrity, the clonogenic capacity of PL cells is more closely linked to tooth survival rate, probably reflecting the capacity of PL progenitor cells to recolonize the root surface after replantation. 相似文献
76.
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
77.
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
78.
Yasunori Utsunomiya Toshiyuki Imasawa Aya Abe Keita Hirano Tetsuya Kawamura Ryuji Nagasawa Tetsuya Mitarai Naoki Maruyama Osamu Sakai 《Clinical and experimental nephrology》1997,1(2):83-91
Background The purpose of this study was to examine the effects of bacterial suporantigens, which can derange the immune response and
contribute to the renal lesions of immunoglobulin A (lgA) nephropathy.
Methods Twenty-five micrograms of a bacterial superantigen, staphylococcal enterotoxin B (SEB), was injected into IgA nephropathy-prone
ddY mice intrathymically when they reached 6 weeks of age. Evaluation included measurement of albumin excretion in urine,
immunoglobulin concentration, and lymphokine production in vitro, as well as analysis of T-cell receptor expression in splenic
T-cell subsets and examination of renal histology by light and fluorescence microscopy.
Results At 40 weeks of age, the serum level of IgA in these mice was substantially increased and the number of Vβ8+ CD4+splenic T-cells was significantly decreased compared with measurements in untreated controls. Both control and SEB-treated
mice excreted less than 30 μg/mL of urinary albumin. In mice given SEB, the amount of interleukin 2 (IL-2) and tumor necrosis
factor-α (T helper 1 [Th1]-type cytokines) produced by the in vitro-stimulated lymphocytes significantly decreased. whereas
that of interleukin 4 (IL-4) and interleukin 6 (IL-6) (Th2-type cytokines) markedly increased compared with measurements in
control mice. At 40 weeks of age, mice given SEB showed marked glomerular hypercellularity and enhanced glomerular C3 deposition
by renal histology, compared with control mice.
Conclusion These results suggest that bacterial superantigen SEB may modify glomerular lesions through activating Th2 cells, while inducing
deletion of Th1 cells in this experimental model. 相似文献
79.
Y Abe S Ogino M Irifune T Matsunaga I Imamura H Fukui H Wada 《Nihon Jibiinkoka Gakkai kaiho》1991,94(8):1113-1122
Histamine (HA) is the most important mediator of nasal allergy and nasal hypersensitivity. To investigate HA metabolism, HA content and activities of its synthetic enzyme, histidine decarboxylase (HDC) and degrading enzymes, histamine-N-methyltransferase (HMT) and diamine oxidase (DAO) in nasal mucosa of human and toluene diisocyanate (TDI) sensitized guinea-pigs were measured. In human nasal mucosa and nasal polyps, HA content and HDC activity were 80-200 nmol/g tissue, 20-30 fmol/min/mg protein respectively. Among two degrading enzymes, HMT activity was 20-200 times higher than that of DAO. In the nasal mucosa of guinea-pigs, HA content was significantly increased by TDI sensitization, and was decreased immediately after TDI provocation. In 24 hours after provocation, HA content recovered to 80% of pre-provocation level. HDC activity increased by TDI sensitization significantly. Though HMT activity increased slightly by TDI sensitization and provocation, DAO activity was unchanged. The data suggest that, increase in turnover rate of HA is present in allergic nasal mucosa. 相似文献
80.
H Saito K Kishi M Narita T Furukawa E Nagura T Maekawa T Abe A Shibata 《Leukemia research》1992,16(3):217-226
To test the relationship between DMs and drug resistance in newly established AML cell lines, KY821, and its clone KY821A3, the latter had lost DMs during cloning, were cultured in increasing concentrations of MTX. KY821 became resistant against 2 x 10(-4) M MTX, whereas KY821A3 did against 2 x 10(-5) M MTX in a same period. Enhanced enzyme activities of DHFR were correspondent to the increased DMs numbers and DHFR gene amplification in both resistant clones. The amplified DHFR gene was located on DMs by in situ hybridization. These data indicated that the presence of DMs in KY821 would facilitate the acquisition of drug resistance. 相似文献