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991.
Zusammenfassung
Videofluorographie und Kinematographie gelten derzeit als Goldstandard für die Abkl?rung von Schluckst?rungen. Methodisch
bedingt ist jedoch keine überlagerungsfreie Darstellung der anatomisch wichtigen Strukturen des Pharynx m?glich, so da? bei
manchen St?rungen nicht unterschieden werden kann, ob diese pathoanatomisch oder funktionell-neurogen bedingt sind. Anhand
von 3 Fallbeispielen wird dargelegt, ob und in welchem Umfang die Elektronenstrahlcomputertomographie mit ihrem hohen r?umlichen
und zeitlichen Aufl?sungsverm?gen (Millisekundenbereich) diese Nachteile kompensiert. Es ist uns gelungen zu zeigen, da? die
vollst?ndige und symmetrische nasopharyngeale Abdichtung durch den Passavantschen Wulst und den weichen Gaumen gew?hrleistet
wird. Durch die EBT konnte die genaue anatomische Lokalisation und Ausbreitung eines lateralen hypopharyngealen Pouches dargestellt
werden. Durch den Nachweis einer Kompression des oberen ?sophagussphinkters durch einen kleinen zervikalen Spondylophyten
konnte eine scheinbar nur funktionell bedingte Dysfunktion weiter abgekl?rt werden. Diese Beispiele zeigen, da? die Elektronenstrahlcomputertomographie
die sich funktionell ?ndernde Anatomie w?hrend des Schluckens in der Transversalschicht darstellen kann, und legen es nahe,
ihre Wertigkeit auf der Basis systemischer interdisziplin?rer Untersuchungen zu evaluieren.
相似文献
992.
M. Ïmer T. Okar S. Çobanoğlu R. Kayapinar M. Memiş K. Hepgül K. Kutlu 《Acta neurochirurgica》1996,138(10):1246-1249
Summary Modification of a type of end-to-side anastomosis that has been described before is studied. The recipient artery is occluded for only 3–4 minutes to complete the anastomosis by using only the running suture. The anastomotic site was studied by inspection and Scanning Electron Microscope (SEM) at different times after the operation on 30 rats. 相似文献
993.
Jörg Bohmeyer Andreas Heller Christine Hartig Margaretha Westenberger-Treumann Hans Huchzermeyer Heinz-Günter Otte Rudolf Stadler 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1996,47(2):106-108
Zusammenfassung
Trotz der H?ufigkeit der Erkrankung liegen nur wenige gesicherte Erkenntnisse über die ?tiologie der chronischen Urtikaria
vor. Bei 10 Patienten, bei denen keine anderweitige Ursache für die Erkrankung ermittelt werden konnte, führten wir eine Gastroskopie
durch. Bei 8 der 10 Patienten konnte eine Besiedlung der Magenschleimhaut mit Helicobacter pylori gesichert werden. Die Urtikaria
heilte innerhalb weniger Tage bei allen Patienten ab, nachdem wir eine Therapie mit Amoxicillin und Omeprazol einleiteten.
Eingegangen am 6. Februar 1995 Angenommen am 12. Mai 1995 相似文献
994.
Prof Dr. Siegfried E. Miederer MD Peter Grübel MD 《Digestive diseases and sciences》1996,41(5):944-949
The effect of pH onH. pylori urease activity in its ecological niche was studied in gastric antral biopsy specimens. Specimens were incubated in 10 mmol/liter urea solutions at pH range 3.3–8.2. Activity of urease was studied by measuring production of ammonia and change in pH of the solutions. Urease activity was reduced at pH 8.2 (1424 ± 218 µmol/liter) but decreasing initial pH to neutral and acidic values resulted in significant maximal 6.5-fold increase in ammonia production (9491 ± 1073 µmol/liter,P<0.0005), which considerably raised the pH of the test solutions. Peak urease activity was between pH 5.0 and 7.0. In contrast to specimens incubated initially at pH 8.0, reincubation of washed specimens from solutions with initial pH 7.0 showed eightfold decreased urease activity. It is concluded that urease activity is markedly pH dependent with pH optima below the physiological mucosal surface pH. Furthermore, availability of urease is limited. Thus, an impaired gastric mucosal integrity allowing back diffusion of hydrogen ions may release urease activity, which might further weaken the mucus barrier and damage the gastric epithelium.This study was supported by the Deutsche Forschungsgemeinschaft (Mi 190/3). 相似文献
995.
H. Klüter I. Dörges E. Maass T. Wagner H. Bartels H. Kirchner 《Annals of hematology》1996,73(2):85-89
Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method
for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis.
PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus.
PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC
(day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion,
corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic
patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly
were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased
with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy
coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference
from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient
platelet increment even when stored for up to 5 days.
Received: 28 December 1995 / Accepted: 14 May 1996 相似文献
996.
A. Schlüter 《Der Radiologe》1998,38(5):450-453
Ohne Zusammenfassung 相似文献
997.
The effects of left- and right-sided hemispheric brain infarction on variability in circadian blood pressure and cardiovascular measures were investigated in 35 patients to test for asymmetry of the sympathetic consequences of stroke. No significant differences regarding age, size of infarction or extent and frequency of damage to the insular cortex could be detected between the two groups. Patients with right-sided infarction showed a significantly reduced circadian blood pressure variability [diastolic: -1% (95% CI -4 to 1) vs -6% (-9 to -2);P < 0.05] and a higher frequency of nocturnal blood pressure increase (47% vs 35%;P < 0.05) as compared with patients with left-sided infarction. Right-sided infarction was also associated with higher serum noradrenaline concentrations [546 pg/ml (95% CI 415–677) vs 405 pg/ml (266–544);P < 0.05], and ECG more frequently showed QT prolongation (53% vs 35%;P < 0.05) and cardiac arrhythmias (67% vs 20%;P < 0.005). However, irrespective of the hemisphere damaged, patients with insular infarction showed the most pronounced changes of these parameters. In addition, two patients with right-sided strokes (13%) involving the insula, but none with a left-sided infarction, developed myocardial infarction. These findings suggest lateralization of sympathetic activation with right-sided dominance for sympathetic effects following hemispheric stroke.Supported by the Friedrich-Schiedel-Stiftung 相似文献
998.
999.
G. Hege-Scheuing K. Michaelsen A. Bühler J. Kustermann W. Seeling 《Der Anaesthesist》1995,44(5):351-358
Previous studies investigating the peripheral action of locally instilled morphine after arthroscopic knee surgery found evidence for an analgesic effect. Follow-up studies have lead to conflicting results.We used patient-controlled analgesia (PCA) to test the analgesic potency of intraarticular morphine. Methods. Patients undergoing arthroscopic knee surgery under general anaesthesia received, after written informed consent and in double-blind and randomised manner, 1?mg morphine diluted in 10?ml saline either intraarticularly or intravenously at the end of the surgical procedure. A control injection of 10?ml saline was given at the other site. The pain intensity on a visual analogue scale (VAS) and the cumulative morphine consumption were recorded at 1, 2, 3, 4, 6, 8 and 24?h after the end of general anaesthesia. Statistics: Wilcoxon rank sum test with P<0.05. Results. A total of 59?patients were included in the study; 29 received morphine intraarticularly (verum group), 30 intravenously (control group). There was no difference in gender, age, duration of arthroscopy or anaesthesia. There were more than 60% diagnostic arthroscopies in both groups; other types of surgery were comparable, with the exception of cruciate band repair procedures only in the control group. We found no difference in morphine consumption or pain intensity between the two groups throughout the study period. Median overall consumption of morphine after 24?h was 14?mg in the verum group and 15?mg in the control group, with wide interindividual variation. Pain intensities were remarkably low. The peak pain intensity of both groups was found at 1?h postoperatively, with median 16/100 on the VAS in both groups. Blinding was robust. Conclusion. We found no reduction in postoperative morphine supplementation after 1?mg morphine intraarticularly compared to 1?mg intravenously given at the end of knee arthroscopies. There were also no differences in pain intensities on a VAS. We conclude that titration of postoperative pain with a morphine-filled PCA pump was unable to show a difference in analgesic potency between intraarticular and intravenous morphine. 相似文献
1000.
The mode of action and the structure of a herbicide in complex with its target: binding of activated hydantocidin to the feedback regulation site of adenylosuccinate synthetase. 总被引:4,自引:0,他引:4 下载免费PDF全文
R Fonné-Pfister P Chemla E Ward M Girardet K E Kreuz R B Honzatko H J Fromm H P Sch?r M G Grütter S W Cowan-Jacob 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(18):9431-9436
(+)-Hydantocidin, a recently discovered natural spironucleoside with potent herbicidal activity, is shown to be a proherbicide that, after phosphorylation at the 5' position, inhibits adenylosuccinate synthetase, an enzyme involved in de novo purine synthesis. The mode of binding of hydantocidin 5'-monophosphate to the target enzyme was analyzed by determining the crystal structure of the enzyme-inhibitor complex at 2.6-A resolution. It was found that adenylosuccinate synthetase binds the phosphorylated compound in the same fashion as it does adenosine 5'-monophosphate, the natural feedback regulator of this enzyme. This work provides the first crystal structure of a herbicide-target complex reported to date. 相似文献