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71.
In a prospective study, the systemic inflammatory consequences of surgery-induced lung tissue injury were evaluated using biochemical markers. The aim was to examine whether this type of injury produces a specific pattern of prostanoid plasma levels (prostacyclin, thromboxane, PGE2, PGF, and PGM). We, therefore, compared 18 patients (group 1) who underwent thoracotomy without injury to the lung with 26 patients (group 2) that had a resection of pulmonary tissue due to benign diseases. Group 2 patients clearly revealed increased plasma levels of C-reactive protein as well as of the granulocyte-specific PMN-elastase. In particular, there was a pronounced release of prostacyclin and its antagonist thromboxane A2 following lung tissue resection. In contrast to group 1 patients, lung tissue damage resulted in immediately elevated plasma levels of PGF and PGE2. When, however, taking into account the time course of PGM, the stable cleavage product of PGF, there was no hint of an altered pulmonary metabolic capacity. Presumably, this pattern of elevated prostanoid levels in group 2 is the result of the surgical damage to the lung tissue. Therefore, it can be suggested to be specific for that type of injury. Thus, the release of prostanoids following surgery-induced lung tissue damage may indicate the importance of these mediators, particularly in thoracic injuries associated with lung damage since those may lead to post-traumatic pulmonary dysfunction. These substances may also be useful in evaluating both the severity and the extent of lung tissue damage following major trauma.  相似文献   
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The objective of the study was to assess scintigraphic patterns and femoral shortening after femoral neck fracture in order to select predictive parameters for late complications. Eighty-eight patients with osteosynthesized femoral neck fractures were followed for 2 years with regular scintigraphic evaluations and orthoradiographic measurements of femoral length shortening. Four different patient categories were identified with regard to the late outcome: two different groups with uneventful healing and two different groups with late complications. Accordingly, a high scintigraphic uptake at 1 month may eiher point to an uneventful healing if combined with minor femoral shortening or indicate failure if combined with a high degree of femoral shortening. In contrast, low scintigraphic uptake may either reflect primary fracture healing if accompanied by minor femoral shortening or predict failure if a high degree of femoral shortening is present. Compared with using scintigraphy alone, combined scintigraphic evaluation and assessment of femoral shortening increased the accuracy for prediction of late failures from 80% to 93%. Early scintigraphic patterns after osteosynthesis of femoral neck fractures have to be validated with care. Radiographic assessment of femoral shortening, which is less invasive, gives better prognostic accuracy and should therefore be preferred for this purpose.  相似文献   
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The intramedullary tibial nail with a proximal angle according to Herzog was developed in order to facilitate implantation. However, the modified technique of unreamed nailing also required a shift of the point of insertion; as a consequence the proximal angle required a considerable increase in the force necessary to introduce the nail. In a study using four cadaver bones and five commercially available unreamed femoral and tibial nails, the authors demonstrate this considerable increase in insertion force and the development of pressure in the medullary cavity. The measurements made with our experimental setup clearly show that the proximal angle of the unreamed tibial nails available for our series does not have a favourable influence on insertion behaviour. As it appears, it results in an increase in the force required for insertion of the nail, thus also causing a greater strain on the bone and an increase in pressure in the medullary cavity. In contrast, the continuous bend of the nail results in a much smoother course of pressure development in the medullary cavity, which does not reach the same high values as with the unreamed tibial nails, despite the fact that less time is required for insertion of the nail. In our opinion, modification of the axial shape of the nail would result both in better implantability and easier removal. We therefore advocate such a modification of the axial shape of intramedullary tibia nails.  相似文献   
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A wide variety of biological and alloplastic injectable biomaterials are available for soft tissue augmentation, but the ideal material has not yet been discovered. Biological materials such as collagen and hyaluronan yield temporary results, while injectable alloplasts are apt to cause varying degrees of foreign body reactions that may result in lumps and chronic inflammation.We present two cases (one is the first filed case in the world) of migratory subcutaneous inflammatory masses secondary to injection of acrylic hydrogel (DermaLive), which is an alloplastic biomaterial recently introduced into the market in Europe. Histology revealed foreign body reaction to acrylic hydrogel with granuloma formation containing multinucleated giant cells. Following this, further reports on complications have been reported elsewhere in Europe. The use and development of injectable materials, as well as alternative methods and future directions are reviewed.  相似文献   
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Zusammenfassung Einleitung: Das Ziel dieser Studie war die Entwicklung eines spezifischen Schweregradklassifizierungssystems für die Beurteilung und Vorhersage von Organfunktionsstörungen und Überleben bei herzchirurgischen Intensivpatienten. Methoden: Hierzu wurden konsekutiv alle erwachsenen Patienten nach einem herzchirurgischen Eingriff unter Einsatz der Herzlungenmaschine über einen Zeitraum von 3 Jahren in die Studie aufgenommen. Im Konstruktionsset erfolgte die Auswahl der Variablen mit Hilfe der Patienten, die mindestens 24 Stunden auf der Intensivstation verbrachten. Die Ergebnisse wurden dann in zwei Validierungssets mit allen Intensivpatienten überprüft. Die Qualität des Scores wurde mit dem Hosmer-Lemeshow-Test (HL) sowie der ROC-Analyse beurteilt, und mit dem APACHE-II- und dem MODS-Score verglichen. Ergebnisse: Insgesamt wurden 3230 Patienten über einen Zeitraum von 3 Jahren auf unserer Intensivstation aufgenommen. Die HL-Werte für den neuen Score waren 5,8 (APACHE-II: 11,3; MODS: 9,7) für das Konstruktionsset, 7,2 (APACHE-II: 8,0; MODS: 4,5) für das Validierungsset I und 5,9 für das Validierungsset II. Die Fläche unter der ROC-Kurve war 0,91 (APACHE-II: 0,86; MODS: 0,84) für den neuen Score im Konstruktionsset, 0,88 (APACHE-II: 0,84; MODS: 0,84) in dem Validierungsset I, und 0,92 in dem Validierungsset II. Schlussfolgerung: Der neue CASUS (Cardiac Surgery Score) zeigt für herzchirurgische Intensivpatienten eine exzellente Kalibrierung und Diskriminierung bezüglich der 30-Tage-Letalität. Die Variablen des CASUS sind einfach, reproduzierbar und werden routinemäßig in herzchirurgischen Intensivstationen erfasst. Der CASUS könnte als Expertensystem für das Diagnostizieren von Organfunktionsstörungen, der Entscheidungsfindung, der Ressourcenauswertung und Vorhersage der Letalität für herzchirurgische Intensivpatienten dienen.  相似文献   
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