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991.
In order to define precisely the relation between descending monoaminergic systems and the motor system, we measured in the ventral horn of spinal cord of adult rats the variations of extracellular concentrations of 5-HT, 5-HIAA, DA and MHPG. Measurements were performed during rest, endurance running on a treadmill, and a post-exercise period, with microdialysis probes implanted permanently for 45 days. We found a slight decrease in both 5-HT and 5-HIAA during locomotion with a more marked decrease during the post-exercise period compared to the mean of rest values. In contrast, the concentration of DA and MHPG increased slightly during the exercise and decreased thereafter. These results, when compared with those of a previous study, which measured monoamines in the spinal cord white matter [C. Gerin, D. Bécquet, A. Privat, Direct evidence for the link between monoaminergic descending pathways and motor activity: I. A study with microdialysis probes implanted in the ventral funiculus of the spinal cord, Brain Res. 704 (1995) 191–201], highlight the complex regulation of the release of monoamines that occurs in the ventral horn. 相似文献
992.
993.
Klaus-Dietmar Merboldt Gunnar Krüger Wolfgang Hnicke Andreas Kleinschmidt Jens Frahm 《Magnetic resonance in medicine》1995,34(4):639-644
Functional mapping of human brain activation has been accomplished at high spatial and temporal resolution (voxel size 4.9 μl, temporal increment 100 ms). The approach was based on oxygenation-sensitive long-echo time FLASH MRI sequences synchronized to multiply repeated cycles of visual stimulation in a CINE acquisition mode. This high temporal resolution revealed that stimulus-related signal intensity changes in human visual cortex display an initial latency followed by increases extending over several seconds. Furthermore, the temporal characteristics of the complete CINE MRI signal time course depended on the absolute and relative durations of activation and control periods and, for example, caused an apparent absence of a poststimulation “undershoot” phenomenon. Complementing hyperoxygenation due to rapid hemodynamic adjustments, these results suggest signal intensity modulation by enhanced oxygen consumption and concomitant deoxygenation during prolonged and/or repetitive stimulation. 相似文献
994.
Kazunari Okada Yang Il Kim Kimihiro Nakashima Izuru Tada Takanori Yoshida Michio Kobayashi Shigeo Yokoyama 《Surgery today》1993,23(7):626-631
A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease. 相似文献
995.
L. Barkholt F. P. Reinholt N. Teramoto M. Enbom H. Dahl A. Linde 《Transplant international》1998,11(5):336-344
A nested polymerase chain reaction (nPCR) for Epstein-Barr virus (EBV) DNA, RNA in situ hybridization (EBER-ISH), and immunostaining
against the ZEBRA EBV protein for diagnosis of EBV hepatitis were performed on 43 liver biopsy specimens obtained from 18
patients in the 1st year after liver transplantation (LTX). The findings were related to liver histology and results of EBV-nPCR
on concomitantly obtained serum samples. EBV DNA was detected in 30 % and RNA in 34 % of the liver biopsy specimens using
nPCR and EBER-ISH, respectively, giving a significant correlation between the two methods (P = 0.003). All but one patient had detectable EBV DNA in serum samples obtained within 1 month of the biopsy. More than 90
% of the nPCR and EBER-ISH-positive biopsy specimens were obtained 3 months or less post-LTX. There was no significant difference
in EBV genome findings in biopsy specimens with or without lymphocytic-immunoblastic infiltrates, either in nPCR (P = 0.73) or in ISH (P = 0.73). Two of three biopsy specimens with these histological changes suggesting a viral genesis were positive in EBV-nPCR
but negative in ISH. Histopathological changes in EBV hepatitis may be nonspecific and masked by other complications. The
use of EBV-nPCR and EBER-ISH in liver graft biopsy specimens of heavily immunosuppressed patients may give an early indication
of EBV-related disease and can be used to guide therapeutic intervention.
Received: 5 January 1998 Received after revision: 21 April 1998 Accepted: 20 May 1998 相似文献
996.
We studied the correlation between renal function and pharmacokinetic parameters of inorganic fluoride following sevoflurane
anesthesia. In 30 neurosurgical patients aged 40–70 years, anesthesia was induced with midazolam and sevoflurane and maintained
with sevoflurane and nitrous oxide in oxygen. Serum and urine inorganic fluoride (F−) levels and β2-microglobulin (BMG), blood urea nitrogen (BUN), and serum creatinine (Cr) were measured during and after anesthesia. The
decrease rate of serum F− level and the area under the curve (AUC) of serum F− were calculated. Correlations among sevoflurane dosage, duration of administration, peak serum F− level, AUC, the decrease rate of serum F− level, and the maximum values in BUN, Cr, and urine BMG during the study were investigated. Urine BMG increased significantly
after surgery but returned to the preoperative level in a week. BUN, Cr, and serum BMG remained within normal ranges during
the study. Sevoflurane dosage and duration of administration were significantly correlated with AUC and the maximum value
of urine BMG, but not with the peak serum F− level or the decrease rate of serum F−. AUC was significantly correlated with the maximum value of urine BMG. In sevoflurane anesthesia, sevoflurane dosage, duration
of administration, and AUC affected urine BMG level, but not peak serum F−. 相似文献
997.
超声导向肝组织微波固化的实验研究 总被引:2,自引:0,他引:2
目的:探讨不同穿刺方案形成的肝组织微波凝固区的大小、形态,为临床治疗,特别是大肝癌的治疗,提供实践基础。方法:利用离体新鲜牛肝,比较UMC-I型微波仪单针、两针及多针组合所形成凝固区的大小、形态。结果:单针穿刺可形成3.0cm×4.0cm头宽尾窄的滴水状凝固区。两针组合,距离在2.5~3.0cm之间造成的完全凝固区最大。不同穿刺方案,可形成8cm以下不同直径的球形凝固区。结论:适当的穿刺方案可使8cm以下的球形区域完全凝固 相似文献
998.
Aaro Leinonen Topi Siniluoto Markku Päivänsalo Ari Karttunen Matti I. Kairaluoma Ilkka Suramo 《European radiology》1993,3(3):213-218
Nineteen patients with 49 symptomatic non-neoplastic non-parasitic simple hepatic cysts were subjected to ultrasonographically guided percutaneous aspiration and temporary injection of 99% ethanol into the cyst. Small cysts were treated twice, the large ones three times at the same sitting. The volume of alcohol per injection varied from 20 to 100 ml, depending on the size of the cyst. A cure was usually achieved with one ethanol sclerotherapy treatment. Only minor side effects such as transient pain and temperature elevation occurred. Forty-seven of the 49 cysts could be treated adequately, and did not recur during a follow-up period af 12–40 months. The results indicate that aspiration an and ethanol sclerotherapy is the treatment of choice in patients with symptomatic non-neoplastic simple hepatic cysts or polycystic liver disease.
Correspondence to: A. Leinonen 相似文献
999.
1000.
A. Muñoz-Hoyos I. Amorós-Rodríguez A. Molina-Carballo J. Uberos-Fernández D. Acuña-Castroviejo 《Journal of neural transmission (Vienna, Austria : 1996)》1996,103(7):833-842
Summary To characterize the pineal response to pyridoxine, plasma melatonin was measured in one hundred and twenty children 3 hours after vitamin B6 administration. The children, aged between 1.5 and 8 years, were divided in four groups as follows: a) control day group, grouping 27 children sampled at 9:00 and at 12:00; b) control night group, grouping 29 children sampled at 21:00 and at 24:00; c) pyridoxine day group, grouping 30 children sampled at 9:00, then intravenously (i.v.) injected with 3mg/kg of pyridoxine, and sampled at 12:00; and d) pyridoxine night group, grouping 34 children sampled at 21:00, i.v. injected with 3mg/kg of pyridoxine, and sampled at 24:00. Melatonin concentration was measured by radioimmuno assay. The data obtained showed a significant increase in melatonin levels after pyridoxine administration in the pyridoxine night group (39.87 ± 8.02pg/ml basal vs 88.45 ± 9.21 pg/ml after pyridoxine, p < 0.001). The other groups did not showed significant differences in melatonin concentrations. Statistical analysis shows that the administration of pyridoxine during the nocturnal hours represents a stimulating factor to increase the pineal production of melatonin in children. 相似文献