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61.
Tracer experiments were carried out to compare the plant uptake behavior of Tc and Re from nutrient solutions. Radish plants, transplanted to nutrient solution including various tracers, showed the same uptake and distribution of 95mTc and 183Re. The trend was the same when the 99Tc and stable-Re concentrations were increased in nutrient solution. The behavior of other elements was different from that of Tc and Re. These findings suggest the possible use of Re as the chemical analogue of Tc in soil solution to plant uptake experiments.  相似文献   
62.
63.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
64.
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences].  相似文献   
65.
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors.  相似文献   
66.
The first acute case of methylmercury (MeHg) poisoning by the consumption of fish arose in Minamata, Japan, in 1953. It was officially recognized and called Minamata disease (MD) in 1956. There are still arguments about the definition of MD in terms of its associated clinical symptoms and lesions even 50 years after the initial recognition of MD. Studies on this MD epidemic are reviewed along with its historical background. Since MeHg dispersed from Minamata to the Shiranui Sea, residents living around the sea had been exposed to low-dose MeHg through fish consumption for about 20 years (at least from 1950 to 1968). These chronic MeHg poisoning patients complained of paresthesia at the distal parts of their extremities and around the lips even 30 years after the cessation of exposure to MeHg of anthropogenic origin. The persisting somatosensory disorders after the discontinuation of exposure to MeHg were induced by diffuse damage to the somatosensory cortex, but not by damage to the peripheral nervous system, as previously believed. Based on these findings, symptoms and lesions in MeHg poisoning are reappraised.  相似文献   
67.
Effects of cueing on visuospatial processing in unilateral spatial neglect   总被引:2,自引:0,他引:2  
Patients with typical left unilateral spatial neglect bisected lines after cueing to the left end-point, the fixation point being monitored with an eye camera. They persisted with the point of initial fixation made after cueing and placed the mark there without searching leftwards again. The rightward shift of fixation to the initial point of fixation thus determined the location of the subjective midpoint. We consider that rightward attentional bias increased the amplitude of this shift that was planned on the basis of the perception of the whole line while cueing. This hypothesis may explain smaller but obvious rightward bisection errors found in the cueing condition.  相似文献   
68.
69.
Summary: Matrix metalloproteinases (MP) are important candidates for the degradation of extracellular matrix, but the role of MP in the diseased kidney remains poorly understood. to examine the significance of urinary MP, we first investigated the characteristics of MP in normal rat urine and renal cortex, and then evaluated the urinary MP activity in anti-thymocyte induced glomerulonephritis (Thy.1 GN). Metalloproteinase activity was measured as the EDTA-inhibitable degradation of [3H] gelatin. the enzyme was purified from urine and the renal cortex homogenate in normal Wistar rats by using several chromatographic and gel filtration methods. Both materials contained the identical molecular weight (Mr 126 kDa by gel permeation method) of gelatin-degrading enzymes, the activity of which was inhibited by metal chelating agents and reactivated by ZnC12 but not by other proteinase inhibitors. Thy.1 GN was induced by intravenous injection of rabbit anti-thymocyte serum into rats, and daily urine was collected at sequential time points. Urinary MP activity was markedly reduced soon after the serum injection, and returned to the control level in 9 weeks. Conversely, urinary MP-inhibitor activity (Mr 30 kDa), determined as inhibiting activity against MP derived from renal cortex, showed serial changes strikingly reflected as urinary MP activity. These findings suggested that rat urine contained the MP which seemed to be derived from the renal cortex, and the urinary MP activity was decreased in Thy.1 GN model, probably due to the presence of MP-inhibitor. As urinary MP is likely to reflect intra-renal MP, the evaluation of urinary MP may be useful to search metabolic alteration of extracellular matrix in the diseased kidney.  相似文献   
70.
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   
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