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61.
Fehrenbach A Wittwer T Cornelius J Ochs M Fehrenbach H Wahlers T Richter J 《The Journal of surgical research》1999,82(2):285-293
Ischemia/reperfusion-induced increase in pulmonary microvascular permeability was shown to be reduced after preservation with Celsior. We investigated reimplantation-induced lung injury in isolated, reperfused rat lungs after preservation via the pulmonary artery with Celsior, Celsior + prostacyclin, and reduced-potassium (40 mmol) Euro-Collins solution (40 ml/kg/body wt each) followed by 2 h of cold ischemia. Arterial and veneous oxygen tensions were recorded during 50 min of in vitro reperfusion after which the lungs (10 right lungs per experimental group) were fixed by vascular perfusion. The tissue was further processed for microscopy, and histological changes were quantified stereologically. Lung preservation with Celsior resulted in a significantly higher volume of air-filled alveolar space with a large proportion of widely distended alveoli compared with the other groups. In the Euro-Collins group the fraction of atelectatic alveoli exceeded that observed in Celsior-preserved lungs. In accordance, the difference between arterial and venous oxygen tensions was significant among Euro-Collins- and Celsior-protected lungs, with improved oxygenation values in the Celsior group. In contrast, addition of prostacyclin to Celsior treatment resulted in rather variable structural as well as functional data. There were no differences in the volumes of intraalveolar edema among the groups tested. However, the volume of alveolar tissue was increased in the Euro-Collins group. In conclusion, compared with Euro-Collins and Celsior + prostacyclin solutions, preservation with Celsior resulted in improved structural characteristics which in combination with improved oxygenation parameters supports the prospective advantage of Celsior in clinical organ preservation. 相似文献
62.
The official drug Sennae folium (obtained from Cassia angustifolia and/or C. acutifolia) was found to contain small amounts of volatiles (0.047% based on dry weight) which were analyzed in detail by GC and GC/MS. More than 200 compounds could be detected, 122 of them were identified, representing about 90.7% of the peak area of the total mixture. The volatile constituents can be classified into monoterpenoids (8.8% for sample A and 34.6% for B), sesquiterpenoids (4.2% and 4.0%, respectively), phenylpropanoids (4.2%/15.2%), fatty acids and esters (54.3%/14.2%), and miscellaneous compounds (19.3%/22.7%). Apart from hexadecanoic acid which was strong in both samples (36.8%/9.7%), the occurrence of menthol, geranylacetone, and (E)-anethole is of interest. 相似文献
63.
Gabor F Haberl I Wirth M Richter K Theyer G Baumgartner G Wenzl E Hamilton G 《International journal of oncology》1996,9(3):527-531
The pseudoautosomal encoded MIC2 glycoprotein is a tumor-associated antigen of Ewing's sarcoma (ES) and closely related tumors of unknown function. To investigate the use of this protein as selective drug carrier recombinant MIC2 was coupled to doxorubicin by a two step glutaraldehyde method (molar ratio DOX/MIC2 of 32 and 16). The conjugates showed dose-dependent cytostatic activity against the ES cell line SK-ES1, the peripheral neuroectodermal line KAL and the prostate cancer cell line PC-3 concurrent with reduced toxicity against normal lymphoblasts. In comparison to free doxorubicin the MIC2-doxorubicin conjugates exhibited highest activity against the PC-3 cell line. Confocal microscopy showed intracellular accumulation of MIC2 conjugates. 相似文献
64.
Sixty-two children with operated congenital heart disease (34 with tetralogy of Fallot and 28 with coarctation) ranging in age from 9 to 16 years underwent a detailed psychological examination. The results were compared with children without structural heart disease and with test norm values. The aim of the study was to check findings on intelligence and explore aspects which had been hardly considered previously (for instance learning capability, concentration, mental work-up of disease etc.). We had assumed that there were differences between the Fallot group and that of coarctation, since the former had been handicapped physically prior to surgery. There were differences in terms of logical thinking, where children with coarctation turned out to be better. As far as other variables were concerned there was no significant difference (such as behavioural features), nor was there any difference between boys and girls. The results show that psychic "problems" of cardiac children do not resolve automatically after surgery, but there may be children with persisting psychological peculiarities who require guidance, occasionally even psychotherapy. 相似文献
65.
The focus group is a qualitative research method that involves group interaction based on a selected topic. It generally involves eight to 12 individuals who discuss a particular topic under the direction of a moderator who promotes interaction and guides the discussion on the topic of interest. This paper presents theoretical perspectives and a review of focus group methodology applied in related disciplines. A research project, which applied the focus group methodology, is described to illustrate important principles in utilizing this qualitative research technique. Information related to preparation for focus group sessions, structure, setting, participants, principles related to conducting the session and analysis are presented. The relevance of this methodology for research and practice in mental health also is discussed. 相似文献
66.
Patterns of structural deterioration due to ischemia in Purkinje fibres and different layers of the working myocardium 总被引:1,自引:0,他引:1
P A Schnabel J Richter A Schmiedl F Bach U Bartels B Ramsauer M M Gebhard H J Bretschneider 《The Thoracic and cardiovascular surgeon》1991,39(4):174-182
Cellular and mitochondrial swelling are regarded as typical intra-ischemic alterations ("IIA"), contraction band lesions (CBL), in contrast, as products of post-ischemic reperfusion. The occurrence of both types of structural deterioration was investigated in Purkinje fibres and subendocardial and intramural working myocardium: initially after St. Thomas- or HTK cardioplegia, then during ensuing global ischemia up to the "practical limit of resuscitability", and following post-ischemic reperfusion. Generally, Purkinje fibres are not better preserved than neighbouring working myocardium. Comparing St. Thomas- and HTK cardioplegia, considerable quantitative, but not qualitative differences in the reaction patterns of different cell types or layers arise. Immediately after cardioplegia, CBL are completely lacking in both cell types. During ischemia, CBL occur occasionally in Purkinje fibres and seldom in subendocardial working myocardium, "IIA" predominate. During post-ischemic reperfusion "IIA" tend to reverse in all layers, whereas CBL are found to remain in the subendocardial cell types. In intramural layers, CBL occur only during reperfusion. Thus, we deduce that cardioplegia only modulates the severity of "IIA" and the frequency of CBL, but cannot abolish the particular sensitivity of subendocardial Purkinje fibres to global ischemia. Prerequisites for the development of irreversible CBL are on the one hand ischemic metabolic alterations and corresponding energy deficits, and, on the other hand, a supply of oxygen. The oxygen may be inadequately supplied via diffusion during ischemia or may be subsequently provided by reperfusion. 相似文献
67.
Dr. Dr. E. May Prof. med. W. A. Laabs Priv. -Doz. Dr. K. -D. Richter H. J. Höhling J. Althoff P. Quint A. Hansjürgens 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1982,356(4):231-241
Zusammenfassung Zusätzlich wurden physikalische und chemische Untersuchungen über den Einfluß von dynamischem Interferenzstrom (DIC) auf die Knochenheilung durchgeführt, nachdem bei 24 Schwarzkopfschafen eine Querosteotomie des Radius vorgenommen worden war. Nach instabiler Osteosynthese wurde die Osteotomiezone wiederholt mit DIC verschiedener mA—Stärken behandelt. (Methodische Einzelheiten sind in Teil I beschrieben). Die Behandlung mit dynamischem Interferenzstrom führte im behandelten Gewebe zu steigenden Temperaturen, die von den mA—Stärken abhängig waren. Weiterhin wurden Zusammenhänge zwischen DIC—mA—Intensität und dem Vorkommen von Hydroxyprolin, einer kollagenspezifischen Aminosäure, nachgewiesen, welches eine erhöhte Calcifizierungsaktivität zur Folge hatte. Messungen des Calcium— und Phosphorgehaltes im neugebildeten Knochengewebe wiesen bei den mit DIC behandelten Tieren vollständige Mineralisation zu einem viel früheren Zeitpunkt als bei den unbehandelten, nach gleichem Verfahren operierten Kontrolltieren auf. Ob DIC einen spezifischen Reiz auf die Knochenneubildung heilender Knochen ausübt, ist noch nicht vollständig geklärt.
Bone healing and Dynamic Interferential Current (DIC)
Summary In the course of supplementary physical and chemical investigations of the influence ofDynamicInterferential Current (DIC) on bone healing 24 black-head sheep were subjected to transversal osteotomy of the radius. After an instable osteosynthesis the site was exposed to repeated therapy with DIC of varying mA intensity. (Methodological details are described in part 1.) DIC therapy resulted in altering the temperatures in the treated tissue, dependent on the mA intensity. Further associations were verified between DIC intensity and the occurrence of hydroxyprolin, an amino acid specific collagen, which also reflected increased calcifying activity. Measurements of the calcium and phosphorus levels in the regenerated (newly forming) bone tissue documented full mineralization in the DIC-treated animals at a much earlier date than in the untreated controls that had undergone similar operations. Whether DIC specifically stimulates osteogenesis within healing bones is still unclear.相似文献
68.
Summary Diazepam was metabolized by human foetal liver microsomes to N-desmethyldiazepam and N-methyloxazepam as early as the 13th week of gestation. The metabolic activity was lower than that of microsomes from adult human liver. Diazepam was shown mainly to be hydroxylated to N-methyloxazepam at substrate concentrations higher than 0.1 mM. Diazepam levels above 1.0 mM were inhibitory to the overall metabolic reaction. SKF 525-A inhibited diazepam metabolism by foetal liver microsomes at a concentration of 0.1 mM. The addition of diazepam to foetal and adult human liver microsomes resulted in a type II spectral change. Its inhibition by carbon monoxide indicated that biotransformation of diazepam was performed by the cytochrome P-450-linked mono-oxygenase system. 相似文献
69.
70.
Timmann D Richter S Bestmann S Kalveram KT Konczak J 《Journal of neurology, neurosurgery, and psychiatry》2000,69(3):345-352
OBJECTIVES: To examine changes in predictive control of early antagonist responses to limb perturbations in patients with defined lesions of the cerebellum. METHODS: Eight cerebellar patients and eight sex and age matched control subjects participated. Subjects held a handle that was rotated around the elbow joint. They were instructed to hold the forearm at 90 degrees flexion against a mechanical perturbation. Extensor torque (5 Nm) was applied for 140 ms (pulse), or for 1400 ms (step) through an external motor. Motor responses were tested under two different conditions of anticipatory information. In the expected condition, subjects anticipated and received a pulse. Under the unexpected condition, subjects expected steps, but received unexpected pulses. Biceps and triceps EMG as well as angular kinematics were compared between expected and unexpected pulse perturbations to quantify possible effects of prediction. RESULTS: In all healthy subjects, the degree of overshoot in the return flexion movement was significantly less in expected pulse perturbations compared with unexpected trials. The degree of amplitude reduction was significantly smaller in the patient group than in the control group (22.8% v 40.0%). During the expected trials, latency of peak triceps activity was on average 20% shorter in the control group, but 4% larger in the cerebellar patients. CONCLUSIONS: In the expected condition, controls achieved a significant reduction in angular amplitude by generating triceps activity earlier, whereas the ability to use prediction for adjusting early antagonist responses after limb perturbation was impaired in cerebellar patients. 相似文献