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Osvaldo Chiara Stefania Cimbanassi Alessio Pitidis Sergio Vesconi 《World journal of emergency surgery : WJES》2006,1(1):12-7
Preventable trauma deaths are defined as deaths which could be avoided if optimal care has been delivered. Studies on preventable
trauma deaths have been accomplished initially with panel reviews of pre-hospital and hospital charts. However, several investigators
questioned the reliability and validity of this method because of low reproducibility of implicit judgments when they are
made by different experts. Nevertheless, number of studies were published all around the world and ultimately gained some
credibility, particularly in regions where comparisons were made before and after trauma system implementation with a resultant
fall in mortality. During the last decade of century the method of comparing observed survival with probability of survival
calculated from large trauma registries has obtained popularity. Preventable trauma deaths were identified as deaths occurred
notwithstanding a high calculated probability of survival. In recent years, preventable trauma deaths studies have been replaced
by population-based studies, which use databases representative of overall population, therefore with high epidemiologic value.
These databases contain readily available information which carry out the advantage of objectivity and large numbers. Nowadays,
population-based researches provide the strongest evidence regarding the effectiveness of trauma systems and trauma centers
on patient outcomes. 相似文献
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We have studied the effects of semi-synthetic diets rich in either n-9 (olive oil, OO) or n-6 (corn oil, CO), or n-3 (fish oil, FO, as MaxEPA) fatty acids on the levels of major PUFA in platelet lipids, on the generation of inositol phosphates by [3H]inositol labelled platelets after stimulation with thrombin and of thromboxane B2 (TxB2) by platelet rich plasma (PRP) after stimulation with collagen. The predicted elevations of oleic (OA), linoleic (LA) and eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were observed in platelet lipids of each animal group, but in the MaxEPA fed group accumulation of EPA was associated with depletion of linoleic acid (LA) rather than of arachidonic acid (AA). Basal levels of inositol-tris-phosphate (IP3) in platelets were lowest in the OO group and highest in the CO group, whereas the increment after thrombin stimulation (1 unit/ml NIH) was maximal in the OO group and minimal in the FO group. Instead, when generation of TxB2 by stimulated platelets was evaluated, no appreciable difference among the various groups could be detected, in accordance with the limited modifications of platelet AA content induced by the diets. The overall data indicate that dietary fatty acids modulate the pathway of inositol phosphate generation in rabbit platelets, independently of modifications of TxB2 production. 相似文献
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Alessio Pigazzi Minia Hellan Douglas R. Ewing Benjamin I. Paz Garth H. Ballantyne 《Journal of gastrointestinal surgery》2007,11(6):778-782
Laparoscopic colectomy is a difficult procedure with a long learning curve. We describe in this study our technique for right-
and left-sided laparoscopic medial-to-lateral colectomy. The medial approach involves division of the vascular pedicle first,
followed by mobilization of the mesentery toward the abdominal wall, and finally freeing of the colon along the white line
of Toldt. This approach allows immediate identification of the plane between the mesocolon and the retroperitoneum and renders
the dissection fast and safe. Our series of 50 consecutive laparoscopic colectomies supports this concept. We believe that
surgeons familiar with this technique will have an important tool in their armamentarium to circumvent some of the challenges
of laparoscopic colectomy. 相似文献
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Lupus anticoagulant IgG's (LA) are not directed to phospholipids only, but to a complex of lipid-bound human prothrombin. 总被引:25,自引:0,他引:25
Plasmas from 16 patients that were found to be positive both for anticardiolipin antibodies (ACA) and lupus anticoagulants (LA) were incubated with liposomes that contained anionic phospholipids. In 11 of these plasmas, ACA could be cosedimented with the liposomes in a dose-dependent manner, whereas LA activity of the remaining supernatant was unaffected. LA activity of purified total IgG from 6 patients was measured in three different coagulation tests, using normal plasmas from different species. Prolongation of the aPTT, KCT and dRVV clotting times was observed only with normal plasma from human origin, not with bovine, rat or sheep plasma. Highly purified coagulation factors Xa, Va and prothrombin, both of human and bovine origin, were used to establish for two patient IgG's the effect of LA on the rate of thrombin formation in the presence and absence of lipid vesicles composed of 20 mole% phosphatidylserine and 80 mole% phosphatidylcholine. A strong and dose dependent inhibition by LA was observed only when human prothrombin was used as substrate in the prothrombinase complex in the presence of lipids. No inhibition was found when bovine prothrombin was used as substrate. The inhibitory effect observed in the presence of human prothrombin was independent of the source of factors Xa and Va, and was not found in the absence of lipid. Preliminary binding studies suggest that LA only associate with a lipid surface, provided that human prothrombin and calcium ions are present. These data indicate that LA are not directed to phospholipids alone, but presumably recognize an epitope which becomes exposed upon Ca(2+)-mediated binding of human prothrombin to phospholipids. 相似文献
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We studied the significance of free erythrocyte protoporphyrin (FEP) in relation to iron status, aluminum levels and anemia in uremic patients on chronic dialysis. All but 1 patient showed high FEP values closely related to the degree of anemia. Increased FEP levels are due to a defective heme synthesis, not related to iron deficiency or aluminum overload. Treatment of anemia with recombinant human erythropoietin reduced FEP values. We therefore hypothesize that recombinant human erythropoietin ameliorates an enzymatic defect in heme synthesis. 相似文献
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Livio Presutti Matteo Alicandri Ciufelli Daniele Marchioni Domenico Villari Alessio Marchetti Francesco Mattioli 《Otolaryngology--head and neck surgery》2007,136(3):369-372
OBJECTIVE: The aim of this paper was to describe our surgical technique for the treatment of nasal septal perforations. STUDY AND DESIGN: We studied 31 patients with nasal septal perforation treated with an endoscope-assisted technique, based on a bilateral dissection of monopedicled mucosal flaps from the nasal fossa floor, sutured at the edge of the perforation previously unstuck, without any graft interposed between the two mucosal layers. RESULTS: In our experience with 31 patients, the use of this technique led to the persistent closing (with follow-up for at least one year) of 96.3% of the perforations smaller than 3 cm. CONCLUSIONS: Our technique has the advantage of an endonasal approach, without any external incision, and the use of monopedicled flaps from the nasal fossa floor without any graft interposition, avoiding any other surgical procedure and morbidity in the donor site of the graft. The use of nasal endoscopy permits superior precision in all surgical steps. SIGNIFICANCE: The high success rate in perforations smaller than 3 cm seems to confirm the effectiveness of this technique. 相似文献