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991.
The aim of this study was the clinical, radiographic, and histologic evaluation of the tissue surrounding SLA (sandblasted and acid-etched) implants loaded with a continuous and constant force for 52 weeks, after a healing period of 6 weeks, after implant insertion. SLA implants were placed in the maxilla of 3 dogs and the mandible of 5 dogs after a 12-week healing period after extraction. Abutments were attached to the 6 test implants (2 in the maxilla, 4 in the mandible). Superelastic nickel-titanium coil springs were activated between the SLA implants and the canines, producing a force of 200 g (2 N). Two unloaded implants (1 in the maxilla, 1 in the mandible) served as controls. Histologic analysis showed a corticalization of bone trabeculae, thicker at the loaded than at the unloaded implants. New bone formation at the level of the crest was slightly superior in the test implants. A difference between the tension and compression areas could not be observed in the test implants. The mean bone-implant contact values of the test implants for the maxilla and mandible were 40.23% and 49.33%, respectively. In the control implants, the bone-implant contact value was 67.91% for the maxilla and 49.23% for the mandible. SLA implants can be used as an anchorage unit with confidence, in spite of a short healing period and a prolonged force application. Further studies with different force magnitudes and healing periods are required to clarify the effects of healing period and force magnitude on bone quality and quantity.  相似文献   
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Improvised explosive devices have created a new class of casualties that presents a unique surgical challenge for oral and maxillofacial surgeons. The injury pattern and severity are different from those seen in conventional trauma patients. Because of battlefield circumstances, patients are sometimes delayed significantly in their transport to a trauma center, and they frequently arrive at a trauma center with hypotension, hypothermia, and acidosis. Definitive care is delayed while the hemodynamic status and life-threatening injuries are stabilized. Hospital triage protocols must be well established in advance to prepare a timely response to the mass casualty event. Proper resource use is an ever-evolving challenge for hospital staff during these times.  相似文献   
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The purpose of this study was to evaluate the retinal toxicity of vancomycin and ceftazidime combined into an infusion solution that was intraoculary given after or during vitrectomy. Forty albino rabbits were divided into 4 groups of 10 each. Vitrectomized right eyes of groups 1, 2, and 3 were given recommended doses of vancomycin and ceftazidime alone or combined, while right eyes in the fourth group were vitrectomized using an infusion solution to which was added ceftazidime and vancomycin combination. Toxicity was tested with electroretinography (ERG) and light microscopy. ERG and light microscopy did not show any toxicity signs associated with vancomycin or ceftazidime alone or with combined therapy. Vancomycin and/or ceftazidime can reliably and effectively be used combined in an infusion solution at recommended doses after and during vitrectomy. This treatment modality does not have any toxic effects to retinal structures and is an alternative method to separate injections of the two antimicrobial agents.  相似文献   
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Background and study aimsLiving-related liver transplantation has helped to solve the problem of shortage of deceased organ donors. However, studies showed significant donor complications occurring with adult living liver donation. This study aims at assessing different causes of exclusion of potent living donor transplantation in Egypt.Patients and methodsThe data of 158 living donors (corresponding to 50 consecutive transplanted cases) were retrospectively studied.ResultsOnly 50 donors were found to meet all the preoperative assessment criteria while 108 potential donors were excluded at various assessment steps. Majority of the excluded potential donors were due to anatomical variations (52/108) followed by hepatic steatosis (19/108) and positive hepatitis B or C virus serology (11/108). Regarding the anatomic variations, biliary anomalies were ranked as the first cause to exclude donors with the majority of them having the type C biliary variant. Portal vein variations were the second most common cause of exclusion due to portal vein trifurcation. Hepatic artery variations were detected in a lesser number of excluded donors. No donors were excluded for hepatic vein anomalies.ConclusionAnatomical variations are the most common causes to exempt living liver donors. Preoperative evaluation of anatomical variations, viral serology and hepatic steatosis plays the major role to accept or exclude the potential donors.  相似文献   
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