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81.
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83.
Oberass. Dr. rer. nat. P. Lotz Dr. med. K. D. Kuhl 《European archives of oto-rhino-laryngology》1970,197(2):129-133
Zusammemfassung Die sauren Hydrolysate der cochleären Abschnitte des häutigen Labyrinths von Hausschweinen und Meerschweinchen wurden säulen-chromatographisch zur Differenzierung des Glucos- und Galaktosaminanteils getrennt. In beiden Tierspecies ergab sich ein Überwiegen des Glucosamins gegenüber dem Galaktosamin. Unter Berücksichtigung histochemischer und quantitativer biochemischer Befunde lassen die Analysen den Schluß zu, daß stark saure MPS am Aufbau des häutigen Hörorgans in erheblichem Maße beteiligt sind. Neben dem Keratosulfat als Hauptkomponente sind auch Chondroitinsulfate vertreten. Die stark sauren Eigenschaften dieser Mucopolysaccharide unterstreicht die Theorie ihrer wesentlichen Rolle als Ionenaustauscher bei der Bildung der Innenohrpotentiale.
Herrn Prof. Dr. Dr. h. c. A. Eckert-Möbius zum 80. Geburtstag gewidmet.
Technische Mitarbeit: Frau W. Lehmann. 相似文献
Differentiation of mucopolysaccharide in the inner ear by separation of hexosamine with column-chromatography
Summary The glucose- and galactose-amino components were separated by columnchromatographic differentiation from the hydrolyzed cochlear sections of the membranous labyrinth of the pig and the guinea-pig. They showed in both species more glucosamine than galactosamine. Taken consideration of the histochemical and biochemical findings these analysis may be concluded that a considerable amount of the strong acid mucopolysaccharide is contributed in construction of the membranous hearing organ. In addition to keratosulphate as main components, the chrondroitinsulphate was also present. The strong acidic qualities of the mucopolysaccharide underlined the theory of their important role as ionic exchange upon the formation of the inner ear potential.
Herrn Prof. Dr. Dr. h. c. A. Eckert-Möbius zum 80. Geburtstag gewidmet.
Technische Mitarbeit: Frau W. Lehmann. 相似文献
84.
85.
O.Ass. Dr.rer. nat. P. Lotz Dr. Med. K. -D. Kuhl Dr. Med. D. Brauer Dr. Med. J. Hanson 《European archives of oto-rhino-laryngology》1969,193(4):351-357
Zusammenfassung Das LDH-Isoenzymmuster von 40 menschlichen Tonsillen wurde elektrophoretiseh untersucht. Im Durchschnitt ergibt sich bei den Tonsillen eine etwa gleichstarke Beteiligung des aeroben wie anaeroben Energiestoffwechsels. Eine geschlechtliche Differenzierung war nicht zu erkennen. Mit zunehniendem Alter tritt im paratonsillaren Gewebe and im Kryptenepithel eine leichte Verschiebung zugunsten des anaeroben Stoffwechsels ein In Fallen chronisch rezidivierender Tonsillitis mit Fokalerkrankung war der aerobe Charakter des Energiestoffwechsels besonders im paratonsillaren Gewebe deutlich erhöht, bei Paratonsillitiden deutlich vermindert, ebenso im Kryptenepithel letzterer. Wesentliche Abweichungen von der Norm wurden bei einem Patienten mit einem Morbus Langdon-Down gefunden.
Technische MitarbeitE. Del Mestre u.W. Lehmann. 相似文献
The LDH-isoenzymes distribution in human tonsils and its consequence for the energy-metabolism
Summary The distribution of the LDH isoenzymes of 40 human tonsils has been investigated electrophoretically. The aerobic and anaerobic metabolism was observed without any sex predominance. With the advance of age the paratonsil tissue and the epithelial crypts showed a small displacement towards the anaerobic metabolism. In cases of chronic relapsing tonsillitis with vocal disease the aerobic character especially in the paratonsil tissue was distinctly increased, and in paratonsillitiden and their epithelial crypts were distinctly decreased. Abnormal results were obtained in one patient who suffered from Langdon-Down's disease.
Technische MitarbeitE. Del Mestre u.W. Lehmann. 相似文献
86.
87.
E Beutler W Kuhl J Sorge 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(20):6506-6510
Glucocerebrosidase is the enzyme that is deficient in Gaucher diseases. Four monoclonal antibodies reacting with at least two different epitopes of this enzyme have been produced. The amounts of glucocerebrosidase in fibroblasts of patients with all three types of Gaucher disease were investigated by radioiodinating two of the antibodies and measuring their binding to fibroblast extracts immobilized on nitrocellulose filters. The amount of glucocerebrosidase antigen was decreased in all cases of Gaucher disease, particularly in the fibroblasts of patients with the more severe neuronopathic forms of the disorder, types II and III. The catalytic activity was reduced to a greater extent than the amount of antigen in all cases, so that the specific activity of the residual enzyme was found to be diminished. Although measurements in individual cases were quite reproducible and the amount of antigen detected by monoclonal antibodies reacting with different epitopes was quite similar, there was considerable variation between patients. This finding is consistent with the apparent within-type genetic heterogeneity of Gaucher disease, even within the Ashkenazi Jewish population in which it is most prevalent. 相似文献
88.
Tarsal navicular stress fractures: radiographic evaluation 总被引:3,自引:0,他引:3
Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated. 相似文献
89.
Magnetic resonance imaging of the breast prior to biopsy 总被引:15,自引:0,他引:15
Bluemke DA Gatsonis CA Chen MH DeAngelis GA DeBruhl N Harms S Heywang-Köbrunner SH Hylton N Kuhl CK Lehman C Pisano ED Causer P Schnitt SJ Smazal SF Stelling CB Weatherall PT Schnall MD 《JAMA》2004,292(22):2735-2742
Context Breast magnetic resonance imaging (MRI) has been shown to have high sensitivity for cancer detection and is increasingly used following mammography to evaluate suspicious breast lesions. Objective To determine the accuracy of breast MRI in conjunction with mammography for the detection of breast cancer in patients with suspicious mammographic or clinical findings. Design, Setting, and Patients Prospective multicenter investigation of the International Breast MR Consortium conducted at 14 university hospitals in North America and Europe from June 2, 1998, through October 31, 2001, of 821 patients referred for breast biopsy for American College of Radiology category 4 or 5 mammographic assessment or suspicious clinical or ultrasound finding. Interventions MRI examinations performed prior to breast biopsy; MRI results were interpreted at each site, which were blinded to pathological results. Main Outcome Measures Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of breast MRI. Results Among the 821 patients, there were 404 malignant index lesions, of which 63 were ductal carcinoma in situ (DCIS) and 341 were invasive carcinoma. Of the 417 nonmalignant index lesions, 366 were benign, 47 showed atypical histology, and 4 were lobular carcinoma in situ. The AUC pooled over all institutions was 0.88 (95% confidence interval [CI], 0.86-0.91). MRI correctly detected cancer in 356 of 404 cancer cases (DCIS or invasive cancer), resulting in a sensitivity of 88.1% (95% CI, 84.6%-91.1%), and correctly identified as negative for cancer 281 of 417 cases without cancer, resulting in a specificity of 67.7% (95% CI, 62.7%-71.9%). MRI performance was not significantly affected by mammographic breast density, tumor histology, or menopausal status. The positive predictive values for 356 of 492 patients was 72.4% (95% CI, 68.2%-76.3%) and of mammography for 367 of 695 patients was 52.8% (95% CI, 49.0%-56.6%) (P<.005). Dynamic MRI did not improve the AUC compared with 3-dimensional MRI alone, but the specificity of a washout pattern for 123 of 136 patients without cancer was 90.4% (95% CI, 84%-95%). Conclusions Breast MRI has high sensitivity but only moderate specificity independent of breast density, tumor type, and menopausal status. Although the positive predictive value of MRI is greater than mammography, MRI does not obviate the need for subsequent tissue sampling in this setting. 相似文献
90.
Neurochemical imaging is one of the most established "molecular" imaging techniques. There have been tremendous efforts expended to develop radioligands specific to each neurochemical system. Investigational applications of neurochemical imaging in dementing disorders are extensive. Cholinergic, dopaminergic, and serotonergic systems, as well as benzodiazepine receptors, opioid receptors, and glutamatergic receptors have been imaged in Alzheimer disease and other dementing disorders. These investigations have provided important insights into disease processes in living human patients. The clinical diagnostic use of neurochemical imaging for dementing disorders is currently limited, but this technique is used to help develop therapeutic drugs at multiple levels. 相似文献