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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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Zusammenfassung Grundlagen Die pulmonale Thrombendarterektomie stellt eine effektive Therapie zur Behandlung von Patienten mit chronisch thromboembolischer pulmonalar Hypertonie dar. Wir berichten über unsere Erfahrungen mit dieser Operationstechnik bei den ersten 9 Patienten. Methodik Zwischen 1992 und Oktober 1994 wurde bei 9 Patienten eine pulmonale Thrombendarterektomie durchgeführt. über eine mediane Sternotomie wurden die Pulmonalarterien beider Seiten bis in ihre subsegmentalen Aufzweigungen im Sinne einer echten Endarterektomie vom organisierten thromboembolischen Material befreit. Zumeist waren Perioden des totalen Kreislaufstillstandes in tiefer Hypothermie notwendig, wobei diese zunehmend verkürzt werden konnten und 3 Patienten vollst?ndig ohne Kreislaufstopp operiert wurden. Ergebnisse Die perioperative Mortalit?t betrug 11%, wobei der 1. Patient am 14. postoperativen Tag an den Folgen eines Reperfusions?dems verstarb. Alle anderen Patienten sind 4 bis 22 Monate (im Mittel 13 Monate) nach dem Eingriff am Leben und zeigen eine Hochsignifikante Verbesserung ihrer h?modynamischen Situation (mean PAP pr?operativ: 62 mm Hg, postoperativ: 30 mm Hg p<0,001; Cardiac Index pr?operativ: 2,1 1/min/m2, postoperativ: 3,6 l/min/m2 p=0,001). W?hrend pr?operativ alle Patienten in NYHA-Klasse III oder IV waren, sind die 8 überlebenden jetzt alle in Klasse I oder II. Schlu?folgerungen Die pulmonale Thrombendarterektomie bietet eine erfolgreiche Therapiem?glichkeit für Patienten mit chronisch thromboembolischer pulmonaler Hypertonie mit einer in Anbetracht fehlender konservativer Altermativen akzeptablen Mortalit?t und ausgezeichneten funktionellen Langzeitergebnissen.   相似文献   
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We analyzed the changes in lateral ligament forces during anterior drawer and talar tilt testing and examined ankle joint motion during testing, following an isolated lesion of the anterior talofibular ligament (ATFL) or a combined lesion of the ATFL and calcaneofibular ligament (CFL). 8 cadaver specimens were held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantarflexion and supination-pronation) could be varied in a controlled manner. Ligament forces were measured with buckle transducers, and joint motion was measured with an instrumented spatial linkage. An anterior drawer test was performed using an 80 N anterior translating force, and a talar tilt test was performed using a 5.7 Nm supination torque with intact ligaments, after sectioning of the ATFL, and again after sectioning of the CFL. The tests were repeated at 10° dorsiflexion, neutral, and 10° and 20° plantarflexion. In the intact ankle, the largest increases in ATFL force were observed during testing in plantarflexion, whereas the largest increases in CFL force were observed in dorsiflexion. Isolated ATFL injury caused only small laxity changes, but a pronounced increase in laxity was observed after a combined CFL and ATFL injury.  相似文献   
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Intermediate filaments derived from different cell types are antigenically distinct. Monoclonal antibodies to human intermediate filament proteins can, therefore, be used as tissue-specific reagents capable of distinguishing cell type in poorly differentiated neoplasms. We report a case demonstrating the specificity of antiintermediate filament protein antibodies in establishing a difficult orbital diagnosis of esthesioneuroblastoma.  相似文献   
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In fulminant hepatic failure, the use of bioartificial liver support (BAL) with porcine hepatocytes is the subject of a current and controversial debate.1 Specifically, the issue of cross-species physiological incompatibilities has not been addressed so far. We therefore investigated the effects of species-specific cytokines in single and cocultures on hepatocyte function. Hepatocyte cultures were isolated from human resection specimens and from Landrace pigs. Single and cocultures were exposed to porcine and human interleukin (IL)-6 or tumor necrosis factor (TNF)-alpha. Changes in expression of C-reactive protein (CRP), albumin, CCAAT enhancer binding protein (C/EBP)-alpha and C/EBP-beta and metabolic competence of cultured cells was studied by measuring testosterone metabolite production. After human or porcine IL-6 dosing, CRP was induced up to 100-fold in human hepatocyte cultures, while porcine hepatocytes responded marginally (2- to 5-fold). Treatment with human or porcine IL-6 or TNF-alpha resulted in reduced albumin production, albeit at different levels when human and porcine hepatocytes were compared (P = 0.001). Unlike human, porcine hepatocytes produced less of 6alpha-hydroxytestosterone (6alpha-HT) (P < 0.001) and 7alpha-HT (P < 0.001) after human or porcine IL-6 dosing and treatment with species-specific TNF-alpha induced (human hepatocytes) or decreased (porcine hepatocytes) 6beta-HT production (P = 0.021). In coculture with free exchange of metabolites, porcine hepatocytes produced less 6alpha-HT (P = 0.048) and 16alpha-HT (P = 0.033), whereas after treatment with human IL-6 reduced CRP gene and protein expression was observed with human hepatocytes (P = 0.013). In conclusion, species-specific responses of hepatocytes to cytokines and interactions with xenobiotic metabolites may limit the clinical effectiveness of porcine hepatocytes in BAL.  相似文献   
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Hydranencephaly is defined as the replacement of a previously normal brain, in whole or in part, by membranous fluid-filled sacs. The etiology is not well understood, and the time course of development is unknown. Fifteen ovine fetuses were chronically cannulated and had both carotid arteries ligated at 100 days of gestation (term is 145–150 days). They were killed at 1 (n = 4), 2 (n = 6) and 4 (n = 5) weeks post-surgery, and the findings compared with those of 25 age-matched controls. By 2 weeks post-surgery the entire cerebral hemispheres and diencephalon had been replaced by fluid closely resembling cerebrospinal fluid. The choroid plexus, pituitary and brain stem remained outwardly normal, but the cerebellum showed signs of damage. Fetuses maintained normal values for blood gases and hematocrit up to 4 weeks post-surgery, and grew normally. Light microscopy of the brain stem showed significant losses of cell populations in the medulla by 4 weeks. Vascular casting and acute blood flow studies in an additional group of fetuses showed that the entire brain was perfused via the vertebral-occipital anastomosis immediately after acute bilateral carotid clamping, but that the blood flow rate was insufficient to maintain adequate oxygen delivery. Received: 4 August 1995 / Revised, accepted: 30 November 1995  相似文献   
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