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991.
A case of a 16-year-old girl who showed selective impairment of higher cortical functions and very slight lowering of initiative activity without overt disturbance of consciousness, during prolonged generalized spike-and-wave discharges with a parietal predominance, is reported. Neuropsychological investigations during the episode revealed a disturbance of parietal cortical functions, such as constructional apraxia, ideational or ideomotor apraxia, finger agnosia, acalculia, right-left disorientation, disturbance of visual-spatial orientation, and agraphia. The transient impairment of parietal cortical functions associated with the parietal-dominant spike-and-wave discharges was suggested as a principal pathophysiology of the clinical picture. Emphasis is placed on the importance of neurophysiological assessment in such a case.  相似文献   
992.
Polymeric micelles have potential utility as drug carriers. To this end, polymeric micelles based on AB block copolymers of polyethylene oxide (PEG) and poly(aspartic acid) [p(Asp)] with covalently bound Adriamycin (ADR) were prepared. The micelle forming polymer–drug conjugates [PEO-p(Asp(ADR)] were radiolabeled and their biodistribution was investigated after intravenous injection in mice. Long circulation times in blood for some compositions of PEO-p[Asp(ADR)] conjugates were evident, which are usually atypical of colloidal drug carriers. This was attributed to the low interaction of the PEO corona region of the micelles with biocomponents (e.g., proteins, cells). Low uptake of the PEO-p(Asp(ADR)] conjugates in the liver and spleen was determined. The biodistribution of the PEO-p[Asp(ADR)] conjugates was apparently dependent on micelle stability; stable micelles could maintain circulation in blood, while unstable micelles readily formed free polymer chains which rapidly underwent renal excretion. Long circulation times in blood of PEO-p(Asp(ADR)] conjugates are thought to be prerequisite for enhanced uptake at target sites (e.g., tumors).  相似文献   
993.
A simple and highly reproducible culture method of aortic endothelial cells from cadaver is herein reported. Major bacterial contamination could be prevented by administration of an antibiotic cocktail consisting of gentatnicin, ampicillin, and amphotericin B. Endothelial cells from the thoracic aorta were viable up to 17 hours postmortem and successfully culturable from the aorta by dispase desquamation from the subendothelial substrate. The cultured cells varied in size and shape depending on the degree of individual atherosclerotic severity and could be divided into two major subtypes. The first type is a small and polygonal uniform cell (typical endothelial cell) and the second type is a mixture of spindle and giant bizarre cells often associated with multinuclei (variant endothelial cell). Both types of endothelial cells have characteristics specific for endothelium, such as factor VIII related surface antigen, Weibel-Palade body, and high productivity of prostacyclin.  相似文献   
994.
995.
996.
This report concerns the presence and distribution of Lewy bodies in the peripheral nervous system of three patients with Parkinson's disease and ten age-matched nonparkinsonian individuals. We examined the paravertebral and celiac ganglia as representatives of the sympathetic system; the submandibular ganglion as representative of the parasympathetic system; the esophagus, stomach, duodenum, jejunum, ileum and colon as representatives of the enteric system, and the trigeminal and dorsal spinal ganglia as representatives of the somatic sensory system. Lewy bodies were observed in the peripheral sympathetic and enteric systems of two of the three patients with Parkinson's disease. These two patients had numerous Lewy bodies in the submandibular ganglia. The third patient did not have Lewy bodies in the peripheral autonomic nervous system, nor did the ten control individuals studied. Lewy bodies were not detected in the somatic sensory system of any of the three parkinsonian patients. Our findings indicate that the peripheral autonomic system, including the parasympathetic system is affected in Parkinson's disease.  相似文献   
997.
Abstract: We developed a rotatable, highly durable clipping device (rotatable clip-device) and a long clip which can be used to effectively grasp a large bite of tissue. However, application of the long clip required a special reinforced clipping device. The new rotatable clip-device can be appropriately used in combination with the long clip because of its improved strength and rotatability. The rotatable clip-device was used for endoscopic treatment of 133 patients, including 43 requiring hemostasis of gastrointestinal bleeding, 43 with prophylactic clipping following polypectomy, 39 with mucosal closure following endoscopic mucosal resection (EMR), and 10 undergoing prophylactic ligation of esophageal varices. The long clips were used mainly for mucosal closure after EMR. The rotatable clip-device was found to be especially useful for hemostasis of soft bleeding lesions. Prophylactic clipping following polypectomy prevented complications in 40 out of 41 patients. Mucosal closure by means of clipping following EMR prevented complications in all 39 patients, and the rotatability of the rotatable clip-device and the large bite capacity of the long clip greatly facilitated closing mucosal defects, especially large defects. In the 10 patients who underwent prophylactic clipping of esophageal varices, the rotatable clip-device allowed the varices to be grasped securely and ligated effectively. During endoscopic treatment, three of the four clip-devices functioned normally despite frequent auto-claving and clipping procedures.  相似文献   
998.
Abstract: A new endoscopic drug delivery system was developed by the authors. This system allows for drugs in the form of solid pills, grains, and powders to be delivered to target sites using an air gun propulsion system. Following initial in vitro trials, in vivo studies were performed on dogs, using steel pills, grains of activated carbon, and of sucralfate, and bovine thrombin powder. The depth of pill penetration increased linearly with increases in air pressure. The extent of grain distribution increased in relation to the distance from the tip of the endoscope to the target. Propulsion pressures over certain thresholds (which varied according to the materials propelled) produced bleeding in the stomach wall, but no clearly observed ulceration was observed at any of the pressures tested. The targets were adequately covered by the grains and powder. This drug delivery system shows promise for the treatment of malignant lesions, ulcers and bleeding, and other applications where localized delivery, of drugs is indicated.  相似文献   
999.
Morphological changes in rabbit VX-2 tumor and its vascular permeability to ferritin following hyperthermia, radiotherapy and thermoradiotherapy were investigated by light and electron microscopy. Tumors treated by thermoradiotherapy successively showed a decrease in volume compared with those treated by hyperthermia or radiotherapy. Light microscopically, degenerative or necrotic changes progressed more widely in tumors treated by thermoradiotherapy than in those treated by hyperthermia or radiotherapy alone. When vascular permeability to ferritin was examined, an increase in tumor vascular permeability occurred at 1 day after hyperthermia or thermoradiotherapy, and at 3 days after radiotherapy. These results suggest that the early reaction of tumor microvasculature is a factor contributing to delayed cell death in tumors after thermoradiotherapy or hyperthermia. Acta Pathol Jpn 40: 79–84, 1990.  相似文献   
1000.
Although cancer cachexia has been shown to involve several cytokines, the tumor necrosis factor- (TNF) has rarely been detected in such patients. In this study, sera from 21 patients with cancer cachexia were examined for the presence of TNF and the anti-TNF antibody using an enzyme-linked immunosorbent assay (ELISA) and Western blotting, respectively. All of the patients had recurrent cancer and manifested the characteristics of progressive body weight loss. TNF was found in the sera of four patients (20%) at levels ranging from 10.4 to 53.1 pg/ml, while a positive reaction for the anti-TNF antibody was detected in the sera from six patients (30%), two of whom showed both TNF and its antibody. Thus, either TNF or the anti-TNF antibody was present in the sera from 8 of 21 patients (40%). The results of this study indicate that TNF may be present in the circulation of at least 40% of cachexic patients, and suggest that it may be one of the main mediators of cancer-associated cachexia.  相似文献   
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