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991.
Steady flattening of the tumor, increasing reflectivity and decreasing vascularity are echographic signs of successful irradiation treatment. The specific example of an irradiated choroidal melanoma shows that the absence of echographic changes by no means excludes tumor destruction. Because of a dense vitreous body hemorrhage, the melanoma could only be evaluated echographically. Since the echogram lacked evidence of regression, the tumor was locally resected 5 months later. Histology, however, revealed an amorphous mass of dead tissue pervaded by intact vessels. Apparently a successfully irradiated melanoma may generate an echo typical of vital melanoma tissue. The authors therefore draw the conclusion that only a steady tumor growth, as substantiated by an echogram, may be considered an unambiguous sign of tumor vitality.  相似文献   
992.
Uveal melanoma radiation. 125I brachytherapy versus helium ion irradiation   总被引:4,自引:0,他引:4  
The optimum radiation therapy for uveal melanoma is uncertain. Both helium ion irradiation and 125I brachytherapy have been used to treat this neoplasm. This investigation analyzed the control and complication rates of uveal melanomas treated with helium ions of 125I plaques. In both a retrospective and a prospective dynamically balanced study, the control rates appeared to be similar. There were more posterior segment complications after 125I plaques and more anterior segment complications, including neovascular glaucoma, after helium ion irradiation. The follow-up period is too short to draw definitive conclusions on the radiation complications. Overall, approximately 89% of eyes were retained and less than 4% of treated eyes were removed because of failure to control the tumor.  相似文献   
993.
Two patients with a history of glaucoma and a propensity for uveitis developed ciliochoroidal effusions following Nd:YAG laser posterior capsulotomy. Both patients experienced a waxing and waning course with eventual resolution of symptoms after a steroid regimen. The ciliochoroidal effusions were presumed to be secondary to uveitis induced by the YAG laser surgery. The role of glaucoma, previous surgeries, and an open posterior capsule is uncertain but may have predisposed these patients to ciliochoroidal detachment. We advise caution in performing YAG posterior capsulotomy in patients with glaucoma and a known propensity for uveitis.  相似文献   
994.
995.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.  相似文献   
996.
In the cat synapses between vesicle containing profiles were observed in ventral and dorsolateral pontine nuclei. The presynaptic elements consisted of two types of axon terminals: axon terminals characterized by a population of small (38-40 nm) round synaptic vesicles (SSV) and axon terminals containing pleomorphic synaptic vesicles (PSV). The postsynaptic pale elements (PP) had pleomorphic vesicles and some features attributed to dendrites. In the dorsolateral pontine nucleus most of PP profiles took part in serial synapses, usually as an intermediate component, they were rarely observed in triads. On the basis of their electron microscopical appearance and synaptic relations they might be considered to represent a dendritic part of putative interneurons.  相似文献   
997.
998.
Skin Granulomas due to Mycobacterium gordonae   总被引:2,自引:0,他引:2  
A 38-year-old woman presented with small, ulcerated, red or bluish nodules on the right hand, clinically resembling mycobacterial granulomas; these appeared a few months after a bite by a rat, while the patient was collecting frogs in a pond in the Belgian Ardennes. The histopathologic picture was compatible with a diagnosis of mycobacterial infection and rare acid-fast bacilli could be found. Repeated bacteriologic investigations were performed and these led to the identification of a strain displaying characteristics of Mycobacterium gordonae. The skin condition responded well to rifampicin (300 mg/day) within 6 months.  相似文献   
999.
In the upper limb, diffuse cavernous haemangiomas occur infrequently but their treatment is often unsatisfactory and the result of surgical excision disappointing. Four cases of these diffuse haemangiomas are described and their management discussed.  相似文献   
1000.
Effectiveness of dental health educational programs in schools   总被引:1,自引:0,他引:1  
The largest and most important group that may be reached by health education is found in the school system. Children not only are fast learners and anxious to acquire new skills but also are at risk for the development of dental health problems. Therefore, regardless of the equivocal nature of the evidence regarding the effectiveness of school dental health educational programs, it is important that they continue to be developed. The programs created should have objectives, pretesting, participatory and cognitive experiences, periodic review of dental health program by an advisory committee, a liaison between school personnel and health professionals, and realistic models to assess the effects of the program on health. Because dental disease preventive programs and regimens such as water fluoridation, topical fluorides, dental sealants, and oral hygiene regimens are available that have the potential to eliminate dental disease, effort should be made to increase the awareness of the children who can benefit from them.  相似文献   
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