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61.
Clinical Course and Autopsy Findings of a Patient with Clival Chordoma Who Underwent Multiple Surgeries and Radiation during a 10-Year Period.
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Masashi Tamaki Masaru Aoyagi Toshihiko Kuroiwa Masaaki Yamamoto Seiji Kishimoto Kikuo Ohno 《Skull base》2007,17(5):331-340
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques. 相似文献
62.
A. Mori S. Urabe M. Asada Y. Tanaka H. Tazaki I. Yamamoto N. Kimura T. Ozawa S. T. Morris R. Hickson P. R. Kenyon H. Blair C. B. Choi T. Arai 《Transboundary and Emerging Diseases》2007,54(7):342-345
Concentrations of metabolites and immunoreactive insulin (IRI) and activities of enzymes related to energy metabolism were measured in plasma of Korean and Japanese beef cattle, which were raised by the indoor feeding system programmed to feed larger amount of roughage in their growing periods and larger amount of concentrate diet in their finishing periods (Japanese feeding system), and grazing New Zealand beef cattle. By the Japanese beef grading system, Korean and Japanese beef cattle showed high beef quality score, average grade 3.3 and 3.6, respectively. The plasma free fatty acid and lactate concentrations and lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and aspartate aminotransferase (AST) activities in Korean beef cattle were significantly higher than those in Japanese beef cattle. The plasma lactate concentration in Korean beef cattle was 8.40 mmol/l, which was similar to the values observed in lactic acidosis. The higher activities of plasma LDH, MDH and AST may indicate slight liver damage by slightly acidotic conditions in Korean beef cattle. New Zealand beef cattle fed on pasture which they harvest by grazing showed significantly lower plasma glucose, cholesterol, lactate and IRI concentrations and enzyme activities than those in Korean and Japanese beef cattle fed on larger amount of concentrate diets. Plasma metabolite concentrations and energy metabolism‐related enzyme activities may be good indicators for evaluating metabolic conditions of beef cattle raised by different feeding systems. 相似文献
63.
Masashi Hamada Ritsuko Hanajima Yasuo Terao Noritoshi Arai Toshiaki Furubayashi Satomi Inomata-Terada Akihiro Yugeta Hideyuki Matsumoto Yuichiro Shirota Yoshikazu Ugawa 《Clinical neurophysiology》2007,118(12):2672-2682
OBJECTIVE: Repetitive paired-pulse transcranial magnetic stimulation (TMS) at I-wave periodicity has been shown to induce a motor-evoked potential (MEP) facilitation. We hypothesized that a greater enhancement of motor cortical excitability is provoked by increasing the number of pulses per train beyond those by paired-pulse stimulation (PPS). METHODS: We explored motor cortical excitability changes induced by repetitive application of trains of four monophasic magnetic pulses (quadro-pulse stimulation: QPS) at 1.5-ms intervals, repeated every 5s over the motor cortex projecting to the hand muscles. The aftereffects of QPS were evaluated with MEPs to a single-pulse TMS, motor threshold (MT), and responses to brain-stem stimulation. These effects were compared to those after PPS. To evaluate the QPS safety, we also studied the spread of excitation and after discharge using surface electromyograms (EMGs) of hand and arm muscles. RESULTS: Sizes of MEPs from the hand muscle were enhanced for longer than 75min after QPS; they reverted to the baseline at 90min. Responses to brain-stem stimulation from the hand muscle and cortical MEPs from the forearm muscle were unchanged after QPS over the hand motor area. MT was unaffected by QPS. No spreads of excitation were detected after QPS. The appearance rate of after discharges during QPS was not different from that during sham stimulation. CONCLUSIONS: Results show that QPS can safely induce long-lasting, topographically specific enhancement of motor cortical excitability. SIGNIFICANCE: QPS is more effective than PPS for inducing motor cortical plasticity. 相似文献
64.
Masaaki Kohta Hiroaki Minami Kazuhiro Tanaka Keiichi Kuwamura Takeshi Kondoh Eiji Kohmura 《Journal of clinical neuroscience》2007,14(2):167-170
A 52-year-old man fell from standing and a computed tomography (CT) scan revealed traumatic intracerebral haematoma and subarachnoid haemorrhage in the temporal cortex. He was treated without surgery and discharged. On day 30 after the accident, he had no neurological deficit. On day 37 he complained of headache and urinary incontinence, and on day 39 he was hospitalized due to progressive neurological deterioration (reduced conciousness, dilated pupils, and left hemiplegia). A CT scan revealed a diffuse low-density in the right cerebral hemisphere with marked midline shift. Emergency decompressive craniectomy and right temporal lobectomy were performed. Angiography after surgery revealed moderate vasospasm in the right middle and anterior cerebral arteries. The patient remained severely disabled. Delayed onset neurological deterioration can be caused by brain oedema and vasospasm after traumatic brain injury, despite an intervening period of improvement. 相似文献
65.
By use of a double-labeling immunofluorescence method with a confocal laser scanning microscope, we have examined whether a calcium-binding protein, calretinin, is localized in magnocellular oxytocin and vasopressin neurons of the rat hypothalamus. In the supraoptic nucleus, all oxytocin-labeled cells were stained for calretinin. However, in the magnocellular part of the paraventricular nucleus, almost all oxytocin-stained cells were devoid of calretinin immunoreactivity. All vasopressin-positive cells of both the supraoptic nucleus and the magnocellular part of the paraventricular nucleus lacked calretinin immunoreactivity. No calretinin immunoreactivity was found in oxytocin-labeled cells of the the anterior commissural nucleus or in vasopressin-labeled cells of the suprachiasmatic nucleus. We previously showed that another calcium-binding protein, calbindin-D28k, was localized in magnocellular oxytocin neurons of the supraoptic nucleus but not in those of the paraventricular nucleus. These findings suggest that, in general, magnocellular oxytocin neurons of the supraoptic nucleus and those of the paraventricular nucleus can be chemically distinguished, that is, the former contain both calretinin and calbindin-D28k but the latter lack the two calcium-binding proteins. 相似文献
66.
A case of quadricuspid aortic valve with aortic regurgitation 总被引:2,自引:0,他引:2
A 67-year-old man with grade 3 aortic valve regurgitation was found to have a quadricuspid aortic valve. The aortic valve consisted of 1 large, 2 intermediate and 1 small sized cusp. An accessory cusp located between the right and noncoronary cusps, and shaped like a hammock which sling by the fibrous strings originating from the both commissures to the aortic wall. Aortic valve replacement was successfully performed with a 23 mm St. Jude Medical prosthetic valve, and the patient is asymptomatic five months post-operatively. Histological examination of the resected cusps showed fibrous thickening and no rheumatic valvulitis or infective endocarditis. 相似文献
67.
Takemoto N; Koyano-Nakagawa N; Arai N; Arai K; Yokota T 《International immunology》1997,9(9):1329-1338
68.
Michiko Kawaguchi Masaaki Techigawara Takako Ishihata Tsukasa Asakura Fujiko Saito Kazuhira Maehara Yukio Maruyama 《Heart and vessels》1997,12(6):267-274
Summary The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological
changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial
changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural
changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls
without hypertension or diabetes mellitus (n=6), and patient with hypertension (n=3), diabetes mellitus (n=8), and diabetes with hypertension (n=8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures
were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials
showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement
membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater
in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in
the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective
of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial
cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells
and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately,
to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension. 相似文献
69.
S Arai C Arai M Fujimaki Y Iwamoto M Kawarada Y Saito Y Nomura T Suzuki 《Journal of comparative pathology》1991,104(4):439-441
Cutaneous tumour-like growths were observed on the face and other areas of the body surface of young Chilean flamingos. In the cells of these lesions, avian pox-specific cytoplasmic inclusion bodies were observed by light microscopy and virus particles were detected under an electron-microscope. It was diagnosed as avian pox. 相似文献
70.
Clinical effects of percutaneous cardiopulmonary support in severe heart failure: early results and analysis of complications. 总被引:2,自引:0,他引:2
Shigeru Sakamoto Junichi Matsubara Toshiaki Matsubara Yasuhiro Nagayoshi Shinji Shono Hisateru Nishizawa Masaaki Kanno Katsunori Takeuchi Toshimichi Nonaka Jun Kyosawa 《Annals of thoracic and cardiovascular surgery》2003,9(2):105-110
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage. 相似文献