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Summary Eight patients with malignant gliomas verified on CT scan, received an intravenous injection of 50 mg of Adriamycin R, 24 hours prior to surgical removal of the tumour. Peroperatively, both tumour and surrounding tissue specimens were obtained for determination of the tissue concentrations of Adriamycin and its reduced metabolite Adriamycinol. It was found that Adriamycin could be detected in tumour tissue from all patients. The concentration varied between 0,9 and 4,6 nmol/g tissue. In contrast, Adriamycin could only be detected in surrounding brain tissue from one patient.In anin vitro study a human malignant glioma cell line (U-251 MG) was exposed to various concentrations of Adriamycin for 24 hours. It was found that an intracellular drug concentration above 30 nmol/g cells caused a concentration dependent inhibition of cell growth. Thus, it is likely that the poor effect of Adriamycin on patients with malignant gliomas is due to an ineffective drug accumulation in the tumour tissue.  相似文献   
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A case of a pedunculated arachnoid cyst within the third ventricle is presented. The cyst was small so as not to appear as a significant expanding lesion on CT. The clinical history, however, suggested intermittent increase of the intracranial pressure. On CT there was some widening of the lateral and third ventricles, while the fourth ventricle had normal width. This finding in combination with the clinical history prompted further neuroradiologic examinations, including pneumoencephalography and ventriculography. The presence of a pedunculated mobile cystic lesion within the third ventricle was shown and its nature further elucidated by stereotactic puncture combined with contrast injection into the cyst. After emptying of the cyst, the patient has been free of symptoms during an observation time of 2 years. The diagnostic and differential diagnostic aspects are discussed and the value of traditional neuroradiologic methods emphasized.  相似文献   
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Ecotoxicity of copper to aquatic biota: a review   总被引:3,自引:0,他引:3  
The toxic effects of copper on numerous aquatic flora and fauna has been studied intensely over the past 10 years. In general, there is a consensus that free cupric ions are more toxic if compared with other chemical forms such as organically complexed copper. Biological indicators exhibit a tremendously wide range of sensitivity to copper with toxic effects noted at pCu as low as 10 for some algae, while aquatic macrophytes appear to have a much higher tolerance for copper (pCu less than 5.0). The sensitivity of various groups of organisms seems discrepant and anomalous with accepted standards for drinking water and industrial discharges, and recommended rates of copper sulfate application to water bodies. The toxicity of copper, however, is mitigated by the presence of naturally occurring organic compounds in waters through complexation. The regulatory function of dissolved humic matter will continue to be a vital one for as long as copper is discharged into aquatic environments.  相似文献   
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Metallic taste has been reported from divers working with underwater electric welding and cutting. An in vitro model was designed to simulate the intraoral situation of the divers with respect to the magnetic field. Potentiostatic analyses were performed on amalgam samples exposed to AC and DC magnetic fields. Morphologic changes were analyzed using differential interference light microscopy and scanning electron microscopy. Chemical changes on the surface of the amalgam samples were analyzed with secondary ion mass spectrometry. Results demonstrated that dental amalgams exposed to a specific AC magnetic field underwent morphologic and chemical changes in the superficial amalgam layers.  相似文献   
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 Supportive treatment of patients with haematological disorders mainly takes the form of transfusions of blood and platelets, and sometimes palliative chemotherapy is given. Most patients are treated in hospital or at the outpatient clinic. However, it is often difficult for the patients to arrange to come to the hospital, as they need transport by ambulance or taxi and sometimes a relative to help them. Throughout 1996 we offered such patients supportive treatment at home. A nurse was employed on the project, who was supplied with a car and a mobile telephone. Treatment was given at home. In all, 17 patients were treated, with a total of 90 blood and 40 platelet transfusions. At three visits chemotherapy was administered. No complications were seen, and the patients felt safe and content. We conclude that supportive treatment at home is safe and well accepted by patients and their relatives. In addition, the costs for transportation and hospital care of this patient group were reduced.  相似文献   
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Summary Fourty-two consecutive patients with craniopharyngioma were treated by stereotactic approach, i.e. preferentially stereotactic puncture and installation of colloid isotope into cystic tumours and external stereotactic single dose irradiation to solid tumour parts. In a minority of cases, such treatment was less suitable, and surgical removal and/or radiotherapy was used. There was no peroperative mortality. A long-term follow up (observation time 10–23 years) of the 31 patients alive indicated that they were socially well adapted with a high rate of fulltime work and a low rate of intercurrent disease. In spite of substitution therapy for pituitary insufficiency in most cases, the patients were subjectively seldom disturbed by their disease.Our results support a change in the choice of therapy for craniopharyngioma patients, from open neurosurgery to the less invasive stereotactic techniques.  相似文献   
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Rivkin  Hadassah  Mor  Michael  Chejanovsky  Nor 《Virus genes》1998,17(1):11-19
A local strain of Helicoverpa armigera baculovirus was isolated from infected H. armigera larvae. Infectivity to Helicoverpa cells, restriction enzyme analysis and electron microscopy allowed its identification as a single embedded nucleopolyhedrovirus, designated HaSNPV-IS. Analysis of DNA replication, protein synthesis and polyhedrin expression in HaSNPV-infected cells located the late and very late phases of the viral cycle at 24 and 48 h after infection, respectively. The viral polyhedrin gene was isolated and characterized. It encoded for a polypeptide of 246 amino acid residues. A 32 kDa polypeptide was identified by immunoblot analysis using anti-polyhedrin antiserum. The HaSNPV-IS polyhedrin DNA sequence revealed 99.4% of homology to the HzSNPV polyhedrin. The availability of this efficient replication system and the above knowledge paves the way to future genetic engineering of the HaSNPV. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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