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21.
Basant Pant M. D. Masayuki Sumida Kaoru Kurisu Kazunori Arita Fusao Ikawa Keisuke Migita Munenori Kutsuna Tohru Uozumi 《Neurosurgical review》1997,20(2):108-113
Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery, and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions. 相似文献
22.
T Shimura S Tabata T Terasaki Y Deguchi A Tsuji 《The Journal of pharmacy and pharmacology》1992,44(7):583-588
The transport of ebiratide, a novel adrenocorticotropic hormone (ACTH) analogue, [H-Met-(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8-NH2], through the blood-brain barrier was directly demonstrated in-vivo. [125I]Ebiratide (16.9 MBq mL-1) or [14C]sucrose (29.2 MBq mL-1) known to be restrictively transported through the blood-brain barrier was infused into the rat internal carotid artery at a flow rate of 50 microL min-1 for 10 min, and after 15 min infusion the distribution volume of each compound in the brain parenchyma was determined by the capillary depletion method. The distribution volume of [125I]ebiratide was 167.8 +/- 62.2 microL (g brain)-1, which was about seven times higher than that of [14C]sucrose (24.9 +/- 4.0 microL g brain)-1, indicating the uptake of ebiratide into brain parenchymal cells. During the infusion into the internal carotid artery, brain microdialysis was simultaneously performed to directly collect the brain interstitial fluid as the dialysate. Radioactivity was detected in the dialysate during the [125I]ebiratide infusion and HPLC analysis of the dialysate revealed that the intact ebiratide accounted for greater than or equal to 80% total radioactivity. The concentrations of [125I]ebiratide and [14C]sucrose in the brain interstitial fluid were estimated based on the relative recovery obtained in the in-vitro recovery study. The brain interstitial fluid/internal carotid arterial blood concentration ratio for [125I]ebiratide was determined to be 1.47 x 10(-2) +/- 0.17 x 10(-2) and was about eight times higher than that for [14C]sucrose (1.92 x 10(-3) +/- 0.36 x 10(-3)), indicating significant transport of ebiratide to the brain interstitial fluid.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
23.
Toshio Kawai Kazunori Mizunuma Tomojiro Yasugi Shun'ichi Horiguchi Masayuki Ikeda 《International archives of occupational and environmental health》1994,66(5):309-315
The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels. 相似文献
24.
Patients who have lost a transplanted kidney are widely recognized as high-risk patients for retransplantation. We have found a profound difference in cadaver kidney regraft survival associated with the age and sex of the donor. Kidneys from male cadaver donors yielded significantly higher graft survival rates than kidneys from female donors. The difference in graft survival at one year was 7% for all first transplants (n = 2974), 14% if the recipient was sensitized, and 18% in 688 patients being regrafted. The difference was even more striking in regraft recipients of kidneys from young male donors (72% one-year graft survival) as compared with recipients of kidneys from older female donors (44% one-year graft survival). The donor age and sex effects correlated well with the cause of donor death. Young male donors accounted for 59% of trauma deaths whereas older female donors made up only 7%. Nontrauma donors, on the other hand, were 38% older female and 14% younger male. The survival of trauma-death donor kidneys in regrafted patients was 69% at one year and 37% for nontrauma donor kidneys, a 32% difference (P less than 0.001). These results indicate that regraft survival could be significantly increased through the use of cadaver kidneys from trauma death donors. 相似文献
25.
Abstract: This case report describes a patient with a rectal ulcer who had an unusual defecation habit. Complete healing was recognized colonoscopically after the patient was instructed to break this habit. A polyp of the ascending colon was detected by a barium enema in a 37-year-old man complaining of anal bleeding. He was admitted to our division to undergo a polypectomy. At the time of the polypectomy, a round ulcer, measuring 1 cm in diameter, was detected on the right wall of the rectum 3 cm from the anal verge. A diagnosis of mucosal prolapse syndrome of the rectum could not be made because the patient did not exhibit the characteristic habit of excessive “straining” mentioned by patients with this syndrome, and no characteristic finding of fibromuscular obliteration was found on histological examination of biopsied specimens taken endoscopically from the lesion. Repeated history taking, however, revealed that the patient had the unusual habit of inserting his finger into his rectum after defecation. He broke this habit following instruction to do so. As a result, on colonoscopic examination 15 month later, the ulcer was found to have become a scar: 相似文献
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29.
Satoshi Tobe Kazunori Yoshida Masahiro Yamaguchi Haruko Nishimura Masahito Kawata 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(7):308-310
Papillary fibroelastoma (PFE) is a rare and benign cardiac tumor typically found on the valvular endocardium. In most cases,
PFE is identified incidentally on echocardiography or during cardiac surgery. The patient was a 73-year-old man who had been
treated for hepatocellular carcinoma for 5 years. On echocardiography, a 2.5-cm diameter mass was detected in the pulmonary
trunk just above the pulmonary valve. Through a transpulmonary arterial approach with cardiopulmonary bypass, the mass identified
on the commissure of the right and posterior pulmonary cusp was surgically excised together with the attached endocardium.
Despite the benign histology of PFE, lethal embolic events such as stroke, myocardial infarction, and pulmonary embolism are
reported in some cases. To prevent such complications, tumor identification and surgical excision are essential. 相似文献
30.
Shin-ichi Imamura Tatsui Nagado Yuji Toyomitsu Shigeya Tanaka Kazunori Arita 《Brain and nerve》2006,58(2):151-154
We reported a 57-year-old female patient recently suffering from frequent seizures such as motionless staring and oral automatism. Electroencephalograms showed spikes in the right sphenoidal derivation and magnetic resonance images revealed an abnormal region, most likely related with a migration disorder such as a focal cortical dysplasia. She was diagnosed as mesiotemporal lobe epilepsy associated with a migration disorder. Seizure disappeared after medication therapy was done. No previous literature has described such a case, thus this is the first report of an epilepsy associated with migration disorder newly onset in a patient older than 50 years old. 相似文献