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51.
Two cases are reported in which, after ACL reconstruction with autologous hamstring grafts, tibial polylactide interference
screws migrated into the knee joint. Clinically, both patients presented with recurrent locking of the joint. In one case,
a broken 15 mm-long tip of the screw was found intra-articularly. In the other case, the whole screw had migrated into the
joint cavity. The degradation process of polylactic acid, operative technique and bone quality are discussed as possible reasons
for these complications. 相似文献
52.
Ohne Zusammenfassung 相似文献
53.
Zusammenfassung Hintergrund: Bei Patienten mit stumpfem Thoraxtrauma muss mit einer Contusio cordis gerechnet werden. Das Spektrum der Symptomatik variiert von einer leichten regionalen myokardialen Funktionsstörung bis hin zur Ruptur und zum plötzlichen Herztod. Fallbeschreibung: Ein 27-jähriger Patient wurde nach einem Fußtritt gegen die Brust bei Kammerflimmern reanimiert. Das EKG sowie das Enzymmuster entsprachen denen eines akuten Myokardinfarkts, echokardiographisch zeigte sich eine Hypokinesie apikal und anteroseptal bei mittelgradig reduzierter Pumpfuktion. Die 10 Tage nach dem Trauma durchgeführte Koronarangiographie und Lävokardiographie ergaben einen unauffälligen Befund. Schlussfolgerung: Als Ursache des primären Kammerflimmerns und der initialen elektro- und echokardiographischen Befunde muss aufgrund der Anamnese eine Contusio cordis diskutiert und in der Therapie berücksichtigt werden. Abstract Background: Patients with a blunt chest trauma often sustain myocardial contusion. The spectrum of symptoms varies from regional myocardial dysfunction to myocardial rupture of sudden cardiac death. Case Report: After a kick against his chest, a 27-year-old patient was resuscitated because of ventricular fibrillation. ECG and enzymatic pattern corresponded to an acute myocardial infarction, the echocardiogram revealed an apical and anteroseptal hypokinesia. 10 days after the acute event, coronary arteriography and ventriculography did not show any abnormalities. Conclusion: On the basis of the anamnesis, a myocardial contusion must be discussed as reason for the ventricular fibrillation and the pathologic findings in ECG and echocardiogram. This has to be considered in the therapy. 相似文献
54.
Karl Lehner M.D. Maximilian Reiser Ulrich Gebhardt Andreas Heuck Jürgen Schaff 《Cardiovascular and interventional radiology》1987,10(2):71-74
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized
by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic
agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining
aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific
details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only. 相似文献
55.
Can we predict the outcome of a partial rupture of the anterior cruciate ligament?
A prospective study of 43 cases 总被引:2,自引:0,他引:2
D. Fritschy Andreas Panoussopoulos Richard Wallensten Robin Peter 《Knee surgery, sports traumatology, arthroscopy》1997,5(1):2-5
The concept of partial rupture of the anterior cruciate ligament (ACL) has been confirmed by arthroscopic examination and
palpation. We present a prospective study of 43 patients who were diagnosed arthroscopically as suffering from a partial rupture
of the ACL by the same surgeon. The patients followed a rehabilitation protocol and were examined by an independant observer
after 5 years. Twenty-five patients had a stable knee, whereas 18 eventually suffered a complete ACL rupture. ACL partial
rupture is easily recognizable with arthroscopy, but the quantity and state of the still intact fibres is difficult to assess.
Received: 20 April 1996 Accepted: 17 December 1996 相似文献
56.
Gerhard Adam Jrg Neuerburg Elmar Spüntrup Andreas Mühler Kira Scherer Vet Surg Rolf W. Günther 《Journal of magnetic resonance imaging : JMRI》1994,4(3):462-466
Gadolinium-DTPA (diethylenetriaminepentaacetic acid)-cascade-polymer, a potential new blood pool contrast agent for magnetic resonance (MR) imaging, was compared with a known blood pool agent, Gd-DTPA-polylysine, in an animal model. The relative signal intensities of liver, renal cortex, pancreas, and trunk muscle were assessed in 12 pigs between 4 seconds and 120 minutes after injection of a 20 μmol/kg dose of each contrast agent, by using a FLASH (fast low-angle shot) sequence. Except for muscle, all tissues showed visible enhancement after injection of either contrast agent. After injection of Gd-DTPA-polymer, enhancement patterns in the liver, renal cortex, and pancreas were similar to those seen after injection of Gd-DTPA-polylysine. No statistically significant differences in enhancement between the two contrast agents were found at any time point. The authors conclude that the contrast kinetics of Gd-DTPA-cascade-polymer are similar to those of Gd-DTPA-polylysine and that this agent may also be used as a blood pool contrast agent for MR imaging. 相似文献
57.
Matthias Bollow Wolfgang Knauf Agnieszka Korfel Matthias Taupitz Andreas Schilling Karl-Jürgen Wolf Bernd Hamm 《Journal of magnetic resonance imaging : JMRI》1997,7(1):241-250
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio. 相似文献
58.
Volkmar Heppert Christof Wagner Ulrich Glatzel Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(1):114-120
Osteomyelitis patients feel their social and professional existence is threatened. Health insurances are faced with total treatment costs for each patient with osteomyelitis, which can reach 500.000,00 EUR. We must therefore make every effort, from the first onset of infection, to prevent the condition from becoming chronic and thus keep the potential problems to patients and insurance companies to a minimum: once the condition has become chronic there is absolutely no guarantee that treatment will be successful. Treatment must start with the removal of absolutely all necrotic tissue – soft tissue and bone – and of all implants. As in tumor surgery, en bloc resection is best. Up to now there is still no means of determining the exact limits of the infection. The surgeons's personal experience with osteomyelitis is the most important factor both in the treatment of these cases and therefore in the containment of treatment costs. Bone reconstruction is attempted after the soft tissue defects have been treated, either by bone grafting (defect < 3 cm) or by segment transfer. Modern techniques of reconstruction surgery can yield quite good results even in chronic oxteomyelitis, providing management has been optimum throughout. Patients with osteomyelitis should therefore be treated in specialist hospitals. 相似文献
59.
Pamela Husmann Christoph Bourauel Michael Wessinger Andreas J?ger 《Journal of orofacial orthopedics》2002,22(5):199-211
Background: The vast range of orthodontic wires made of different alloys makes it increasingly difficult for orthodontists to judge them. Coated orthodontic wires form a group of innovative guiding archwires. Material and Methods: In the present in vitro study the frictional behavior of eight coated wires of different dimensions was investigated in archwire-guided canine retraction in the upper jaw. For this purpose five superelastic nickel titanium alloy wires (Titanol/reg; Low Force River Finish Gold and Gold 2: Forestadent®, Pforzheim Germany; Titanol® Superelastic tooth Sentalloy Ionguard: GAC, Central Islip, NY, USA; NITI Imagination: GAC, Central Islip, NY, USA), two #-titanium wires (TMA® Low Friction Ionguard: Ormco, Glendora, CA, USA; TMA® Low Friction Ionguard Purple: Ormco, Glendora, CA, USA) and one steel wire (Stainless steel Imagination: GAC, Central Islip, NY, USA) were selected. The coatings were made of Teflon® or polyethylene, and by ion implantation. Three uncoated archwires (Rematitan® Lite Dimple; Dentaurum, Pforzheim, German; Titanol® Low Force River Finish: Forestadent®, Pforzheim, Germany; BioForce Sentalloy: GAC, Central Islip, NY, USA) were used for comparison purposes. The force losses due to friction were measured using the Orthodontic Measurement and Simulation System (OMSS). Results: The results indicated that all coatings can reduce frictional losses compared with an uncoated reference wire by the same manufacturer. Measured frictional losses ranged from 48.3-6.1% with the Teflon® coatings reducing the frictional losses to less than 10% in some cases. Conclusion: An unequivocal correlation between the surface roughness and frictional forces of the wires could not be verified by scanning electron microscopy. Zusammenfassung Hintergrund: Die Vielzahl an orthodontischen Drähten aus diversen Legierungen macht es die Kieferorthopäden immer schwerer, sie zu beurteilen. Eine Gruppe von neu angebotenen Führungsbögen stellen die beschichteten orthodontischen Drähte dar. Material und Methode: In der vorliegenden In-vitro-Studie wurde das Reibungsverhalten von acht beschichteten Drähten unterschiedlicher Dimension bei den bogengeführten Eckzahnretraktion im Oberkiefer untersucht. Neben fünf Nickel-Titan-Drähten (Titanol® Low Force River Finish Gold und Gold 2: Fa. Forestadent®; Titanol® Superelastic zahnfarben: Fa. Forestadent®; BioForce Sentalloy Ionguard: Fa. GAC; NiTi Imagination: Fa. GAC) wurden zwei #-Titan- (TMA Low Friction Iongard: Fa. Ormco; TMA Low Friction Ionguard Purple: Fa. Ormco) und ein Stahldraht (Stainless Steel Imagination: Fa. GAC) ausgewählt. Die Beschichtungen bestanden aus Teflon®, Polyethylen oder Ionenimplantation. Als Referenz wurden drei unbeschichtete Drähte (Rematitan® Lite Dimple: Fa. Dentaurum; Titanol® Low Force River Finish: Fa. Forestadent®; BioForce Sentalloy: Fa. GAC) in die Untersuchung einbezogen. Die Reibungsverluste wurden mit dem Orthodontischen Mess- und Simulations-System (OMSS) bestimmt. Ergebnisse: Die Ergebnisse zeigten, dass alle Beschichtungen, verglichen mit einem unbeschichteten Referenzdraht desselben Herstellers, eine Reduktion der Reibungsverluste bewirken. Die gemessenen Reibungsverluste lagen zwischen 48,3% und 6,1%, wobei bei Teflon®-Beschichtungen der Reibungsverlust zum Teil auf unter 10% sank. Schlussfolgerung: Ein eindeutiger Zusammenhang zwischen der Oberflächenrauheit und den Friktionswerten der Drähte konnte anhand von rasterelektronenmikroskopischen Aufnahmen nicht bestätigt werden. 相似文献
60.
Johannes Irsch Rudolf Hendriks Hans Tesch Ruud Schuurman Andreas Radbruch 《European journal of immunology》1993,23(2):481-486
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes. 相似文献