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21.
Frank Diesner Dr. med. Dag Moskopp Christoph Schul Hansdetlef Wassmann 《Neurosurgical review》1997,20(4):274-277
A 21-year-old man was injured by a tailboard of a truck. He suffered a severe head injury with bilateral depressed skull fractures necessitating surgical decompression. On admission to the hospital the patient showed bending to pain stimuli (Glasgow Coma Score 5). Anisocoria was noticed from the beginning. Initial intracranial pressure (ICP), measured 3 hours after injury, was 30 mm Hg, and the cerebral perfusion pressure (CPP) was 70 mm Hg. During surgical elevation of the skull fracture on the right side an unexplainable rise of ICP to values of 100 mm Hg occurred, which corresponded to the mean arterial blood pressure (MAP). At the same time both pupils were dilated and fixed indicating a lack of cerebral perfusion. Due to immediate trephination of the opposite side, the ICP was lowered to values below 20 mm Hg, and sufficient cerebral perfusion (above 50 mm Hg) was regained. The patient showed a good recovery and was transferred to a rehabilitation center 5 weeks after injury.This case report emphasizes the importance of early and continuous intracranial pressure monitoring for adequate therapy in neurosurgical emergencies. 相似文献
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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
27.
Dr. Hans-Albert Schumacher Christoph Bourauel Dieter Drescher 《Journal of orofacial orthopedics》1998,59(3):139-149
In orthodontic treatment employing arch guided tooth movement, rectangular wires are usually used to achieve three-dimensional controlled tooth movement. In the intention to optimize sliding mechanics and to improve the comfort of patients, edge beveled rectangular orthodontic wires are offered by different manufacturers. The objective of the study presented was to investigate the influence of differing but defined wire roundings on sliding mechanics of canine retraction. Employing the 0.018″ slot system, 0.016″×0.022″ standard steel wires (Remaloy and Remanium, Dentaurum Comp.) were tested. Force loss due to friction during canine retraction was determined using the Orthodontic Measurement and Simulation System (OMSS). In the arch guided distalization of canines, the average loss of force caused by friction was determined to be approximately 50%. Comparing wires with different edge bevel, the rounded wire in contrast to the wire with sharpest edge configuration results in a reduction of friction. Even a moderate wire rounding of the 0.016″×0.022″ steel wire results in about 10% reduction in frictional losses. However, dynamic analysis of tooth movement with the OMSS shows that there is no further improvement of sliding mechanics using wires with edge bevel exceeding the standard rounding of rectangular wires. In contrast, a strong edge bevel may result in a considerable loss of leveling. 相似文献
28.
Laparoscopic (vs. Open) Live Donor Nephrectomy: A UNOS Database Analysis of Early Graft Function and Survival 总被引:8,自引:0,他引:8
Christoph Troppmann Debra B. Ormond Richard V. Perez 《American journal of transplantation》2003,3(10):1295-1301
The impact of laparoscopic (lap) live donor nephrectomy on early graft function and survival remains controversial. We compared 2734 kidney transplants (tx) from lap donors and 2576 tx from open donors reported to the U.S. United Network for Organ Sharing from 11/1999 to 12/2000. Early function quality (>40 mL urine and/or serum creatinine [creat] decline >25% during the first 24 h post-tx) and delayed function incidence were similar for both groups. Significantly more lap (vs. open) txs, however, had discharge creats greater than 1.4 mg/dL (49.2% vs. 44.9%, p = 0.002) and 2.0 mg/dL (21.8% vs. 19.5%, p = 0.04). But all later creats, early and late rejection, as well as graft survival at 1 year (94.4%, lap tx vs. 94.1%, open tx) were similar for lap and open recipients. Our data suggests that lap nephrectomy is associated with slower early graft function. Rejection rates and short-term graft survival, however, were similar for lap and open graft recipients. Further prospective studies with longer follow up are necessary to assess the potential impact of the laparoscopic procurement mode on early graft function and long-term outcome. 相似文献
29.
Kari T Kivist? Olaf Grisk Ute Hofmann Konrad Meissner Klaus-Uwe M?ritz Christoph Ritter Katja A Arnold Dieter Lutj?ohann Klaus von Bergmann Ingrid Kl?ting Michel Eichelbaum Heyo K Kroemer 《Drug metabolism and disposition》2005,33(11):1593-1596
The aim of this study was to characterize the role of the efflux transporter Mrp2 (Abcc2) in the pharmacokinetics of orally and intravenously administered pravastatin in rats. Eight Mrp2-deficient TR- rats and eight wild-type rats were given an oral dose of 20 mg/kg pravastatin. Four TR- animals and four wild-type animals were studied after intravenous administration of pravastatin (5 mg/kg). The TR(-) rats showed a 6.1-fold higher mean area under the plasma concentration-time curve (AUC) of pravastatin (p < 0.001) after oral administration and a 4.7-fold higher AUC (p < 0.01) after intravenous administration of pravastatin as compared with the wild-type animals. The mean systemic (total) clearance of pravastatin was 4.6-fold higher (39.2 versus 8.50 l/h/kg, p < 0.001) and the mean V 4.3-fold higher (14.1 versus 3.29 l/kg, p < 0.01) in the wild-type rats. The mean renal clearance of pravastatin in the TR(-) rats was 16.5-fold increased as compared with the wild-type animals (0.695 versus 0.042 l/h/kg, p < 0.05). The increased systemic exposure to oral pravastatin in the TR- rats was associated with a greater inhibitory effect on 3-hydroxy-3-methylglutaryl CoA reductase, as shown by smaller lathosterol to cholesterol concentration ratios. These results suggest that the reduced biliary pravastatin excretion in the Mrp2-deficient TR- rats is partly compensated for by increased urinary excretion of pravastatin. Furthermore, intestinal Mrp2 does not appear to play a major role in the oral absorption of pravastatin in normal rats. 相似文献
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