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排序方式: 共有6732条查询结果,搜索用时 93 毫秒
41.
Hajime Kazamatsuri M.D. Tetsuya Hirose M.D. Osamu Kanno M.D. Nobumasa Kato M.D. Hiromoto Yasuda 《Psychiatry and clinical neurosciences》1994,48(4):869-879
Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases. 相似文献
42.
43.
Ventilatory responses at the onset of passive and active exercise with different amount of exercising muscle mass were studied in 10 healthy male subjects. Four exercise tests were performed for each subject with appropriate intervals on the same day, i.e., two voluntary exercises of one leg or both legs and two passive exercises of one leg or both legs. Inspiratory minute volume (VI), end-tidal CO2 and O2 partial pressures (PETCO2, PETO2) were measured breath-by-breath using a hot-wire flowmeter, infrared CO2 analyzer, and a rapid O2 analyzer. Average values of VI were obtained from 5 breaths at rest preceding exercise and the first and second breaths after the onset of exercise. The ventilatory response to exercise was calculated as the difference (delta) between the mean of exercise VI and mean of resting VI. In this study, the PETCO2 decreased by about 0.5 Torr in four exercise tests, though the decrement of PETCO2 was not statistically significant. The average values and standard deviation of delta VI were 4.22 +/- 1.63 l/min for the one leg and 6.46 +/- 1.80 l/min for the two legs in the active exercise, and were 2.46 +/- 1.12 l/min for the one leg and 3.44 +/- 1.55 l/min for the two legs in the passive exercise, respectively. These results suggest that in awake conditions, the ventilatory response at the onset of passive or active exercise does not increase additively with the increasing amount of muscle mass being exercised. 相似文献
44.
Toshifumi Murashita Keishu Yasuda Yoshiro Matsui Norihiko Shiiya Shigeyuki Sasaki Makoto Sakuma 《Surgery today》1997,27(4):368-372
A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders. 相似文献
45.
We compared peroxidizability of neonatal and adult lipoproteins exposed to oxidative stress initiated by an azo-compound. Oxygen uptake showed a two-phase pattern, with slow oxygen uptake in the first phase and faster uptake in the second phase. During the first phase, tocopherol was consumed progressively, inhibiting lipid peroxidation by scavenging peroxy radicals. After the tocopherol concentration fell below a critical level, extensive propagation of chain oxidative reactions produced the rapid oxygen uptake in the second phase. In the first phase of neonatal lipoprotein oxidation, a faster oxygen uptake was observed and the length of this phase was shorter than in adults. The oxygen uptake rate in the second phase was smaller in the neonatal lipoproteins. In other words, neonatal lipoproteins were more susceptible to oxidative stress than were adult ones when tocopherol remained in lipoproteins, but after tocopherol depletion the reverse was true. These results were consistent with the finding that in neonatal lipoproteins the tocopherol/lipid ratio was significantly lower (length of the inhibitory phase was closely correlated to the lipoprotein tocopherol content). In addition, the average number of active bisallylic hydrogen atoms, which are considered to determine the relative susceptibility of polyunsaturated fatty acids to oxidation, was significantly smaller (oxygen uptake rate in the second phase was closely correlated to the active bisallylic hydrogen number) in neonatal lipoproteins, and the ratio of active bisallylic hydrogen to tocopherol content (which closely correlated to oxygen uptake rate in the first phase) was also significantly lower compared with the adult ratio. Under physiologic conditions, an intensive oxidation of lipoproteins sufficient to cause lipoprotein tocopherol to fall below critical levels is unlikely to occur.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
46.
Shigeyuki Sasaki Keishu Yasuda James D. McCully Joseph LoCicero III 《Surgery today》1997,27(12):1154-1159
The purpose of this study was to develop an isolated, pulsatile blood-perfused rat lung model that allows us to evaluate the
preserved lung functions. Lungs isolated from Sprague-Dawley rats, were perfused with venous whole blood by either a pulsatile
or constant flow. The effuent was continuously deoxygenated with a 95% N2/5% CO2 gas mixture. Airway resistance, lung compliance, elastic work, flow resistive work, pulmonary vascular resistance, and blood
gas analysis were assessed. Pressor responses toN
G
-monomethyl-l-arginine (l-NMMA) were compared between pulsatile and constant blood flow. At a flow of 0.1 ml/g body weight/min, pulsatile perfusion
allowed for stable perfusion at least for 2h (mean 162.5±15.1 min) with stable aerodynamic and hemodynamic variables including
blood gas tensions, whereas constant perfusion resulted in immediate lung failure. Whenl-NMMA was added to the perfusate, the mean pulmonary artery pressure did not show any change in the constant flow (6.0±2.6%
increase), but did show a significant increase in the pulsatile flow (45±11% increase). Pulsatile blood flow reduced the pulmonary
vascular resistance relative to the constant flow and allowed for a 2-h perfusion period to evaluate the lung function. The
vasorelaxant mechanism in the pulsatile perfusion is related in part to the endothelial-dependent relaxation observed in the
nitric oxide pathway.
Presented in part at the 79th, Annual Clinical Congress of the American College of Surgeons (ACS) held in San Francisco, CA
USA, 1993. 相似文献
47.
Human GLUT4/muscle-fat glucose-transporter gene. Characterization and genetic variation. 总被引:5,自引:0,他引:5
J B Buse K Yasuda T P Lay T S Seo A L Olson J E Pessin J H Karam S Seino G I Bell 《Diabetes》1992,41(11):1436-1445
48.
Papillo-Choledochectomy in the Operative Management of Mucosal Neoplasms of the Periampullary Region
Kogoro Kasahara Ken Saito Yasuo Kondo Toshihiko Yasuda Yoshikazu Yasuda Masatoshi Nakada Hideo Nagai Kyotaro Kanazawa 《HPB surgery》1993,6(3):211-217
Two patients with mucosal cancer of the periampullary region were treated with papillocholedochectomy,
which entails removal of the papilla of Vater and the whole length of the common bile duct. The neoplasm is dissected out through the plane between the duodenal circular and longitudinal muscles, deep to the sphincter of Oddi and the fibromuscular layer of the bile duct. Pathological examination showed that cancer was confined to the mucosal layer without stromal invasion, and that the operation achieved radical cure. For mucosal cancer, papillo-choledochectomy is
an alternative to pancreatoduodenectomy, provided that repeated frozen-section studies confirm the
completeness of excision. 相似文献
49.
S Sasaki H Yoshida Y Matsui M Sakuma K Yasuda T Tanabe H Chouji 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(2):106-113
The diagnostic value of cine magnetic resonance imaging (cine-MRI) was evaluated in 10 patients with disease of great vessels. The parameters necessary to decide the appropriate treatment, such as presence and extension of intimal flap, DeBakey type classification, identification of the entry, differentiation between true and false lumen, and between thrombosis and slow flow were demonstrated in all patients with dissecting aortic aneurysm. However, abdominal aortic branches could not be demonstrated enough by cine-MRI, therefore conventional AOG was necessary to choose the operative procedure in these cases. In patients with thoracic aortic aneurysm (TAA), cine-MRI was valuable in demonstrating both blood flow and thrombus in the lumen of aneurysm, and AOG was thought to be unnecessary in most cases. Cine-MRI is a promising new technique for the evaluation of diseases of great vessels. 相似文献
50.
Increased MR signal intensity due to cervical myelopathy. Analysis of 29 surgical cases 总被引:6,自引:0,他引:6
Y Matsuda K Miyazaki K Tada A Yasuda T Nakayama H Murakami M Matsuo 《Journal of neurosurgery》1991,74(6):887-892
The cases of 29 patients with cervical myelopathy, who had been treated by anterior spine fusion, were reviewed. The relationship between pre- and postoperative magnetic resonance (MR) images was investigated with special reference to increased signal intensity in the spinal cord on the T2-weighted images and the relevance of this finding to clinical conditions. Preoperatively, there were areas of increased signal intensity in 12 patients whereas there were no areas of increased signal intensity in the other 17. The lesions were not clearly demonstrated on T1-weighted images. The pre- and postoperative clinical condition of the patients whose preoperative MR images showed areas of increased signal intensity in the spinal cord on T2-weighted images was worse than that of the patients who did not have areas of increased signal intensity. Of the 12 patients with regions of increased signal intensity preoperatively, five showed decreased signal intensity postoperatively compared to the preoperative levels and seven had no change. The postoperative recovery of the five patients who showed decreased signal intensity postoperatively was better than that of the seven patients who exhibited no change. The areas of increased MR signal in the spinal cord might be due to edema, cord gliosis, demyelination, or microcavities. 相似文献