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Philipp Metzler Cornelius von Wilmowsky Robert Zimmermann Jörg Wiltfang Karl Andreas Schlegel 《Journal of cranio-maxillo-facial surgery》2012,40(5):409-415
The aim of this study was to investigate de novo bone formation following ectopic site implantation of bone substitutes covered by periosteum, with and without the application of autologous platelet-rich plasma (PRP). Twenty-four weeks after subcutaneous implantation of various bone substitutes (bovine hydroxyapatite (bHAP), phycogenic hydroxyapatite (pHAP), and bioglass (BG)) in 35 mini-pigs, bone regeneration rates were compared microradiographically and histologically. Without PRP, bHAP showed a mean de novo bone formation of 32.41% ± 29.99, in contrast to the other substitute materials where no mineralization could be detected. In combination with PRP, in the bHAP (63.61% ± 12.98; p ± 0.03) and pHAP (34.37 ± 29.38; p = 0.015) group, significantly higher de novo bone formation was ascertained than without PRP. No ossification could be detected in the BG group. In conclusion, bHAP and pHAP bone substitutes in combination with PRP showed a significant positive effect on periosteal cells by de novo bone formation after ectopic, subcutaneous, low-vascular site implantation. 相似文献
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Patients with congenital supravalvar aortic stenosis (SVAS) with associated biventricular outflow tract obstruction and coronary artery abnormalities have a tenuous myocardial oxygen supply/demand relationship. They are at increased risk of acute myocardial ischemia and sudden death, especially during anesthesia. Furthermore, resuscitation during cardiac arrest is frequently unsuccessful. We report a case of perioperative cardiac arrest due to an unexpected cause in a 2 month old with SVAS during a laparoscopic Nissen fundoplication. 相似文献
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OBJECTIVE: To evaluate the effect of a miniaturized extracorporeal circulation system (MECC System) compared to conventional extracorporeal circulation (ECC) regarding liver function in cardiac surgical patients. METHODS: Double indicator dilution measurements were achieved by bolus injection of indocyanine green (ICG) for assessment of cardiac index (CI) and plasma disappearance rate of ICG (PDRig). Measurements were simultaneously performed preoperatively after induction of anaesthesia (T1), following admission on the ICU (T2) and 6 h postoperatively (T3). RESULTS: CI and PDRig were markedly increased after cardiac surgery without significant differences between groups. The percentage increase in CI was significantly correlated to the percentage increase in PDRig in both groups. CONCLUSION: Liver function improved after cardiac surgery in both groups of patients, which may partly be explained by an increase in CI under mild inotrope support. Differences between the extracorporeal circuits with respect to PDRig appear to be minimal in a group of patients without pre-existing liver injury. 相似文献
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Confirmation or exclusion of recent heroin consumption is still one of the major challenges for forensic and clinical toxicologists. A great variety of biomarkers is available for heroin abuse confirmation, including various opium alkaloids (eg, morphine, codeine), street heroin impurities (eg, 6‐acetylcodeine [6‐AC], noscapine, papaverine) as well as associated metabolites (eg, 6‐monoacetylmorphine [6‐MAM], morphine glucuronides). However, the presence of most of these biomarkers cannot solely be attributed to a previous heroin administration but can, among other things, also be due to consumption of poppy seed products (‘poppy seed defense’), opium preparations or specific medications, respectively. A reliable allocation is of great importance in different contexts, for instance in the case of DUID (driving under the influence of drugs) investigations, in driving licence re‐granting processes, in workplace drug testing (WDT), as well as in post‐mortem identification of illicit opiate use. Additionally, differentiation between illicit street heroin abuse and pharmaceutical heroin administration is also important, especially within the frame of heroin‐assisted treatments. Therefore, analysis of multiple biomarkers is recommended when illicit opiate consumption is assumed to obtain the most reliable results possible. Beyond that, interpretation of positive opiate test results requires a profound insight into the great variety of biomarkers available and their validity regarding the alleged consumption. This paper aims to provide an overview of the wide variety of heroin abuse biomarkers described in the literature and to review them regarding their utility and reliability in daily routine analysis. 相似文献
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