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OBJECTIVE: The aim of the current study was to test the impact of dentin powder on the antimicrobial efficacy of bioactive glass S53P4 (BAG). STUDY DESIGN: BAG was suspended (preincubated) in saline at 37 degrees C for different time periods with or without human dentin powder, hydroxylapatite, or decalcified dentin. Subsequently, Enterococcus faecalis ATCC 29212 cells were added to these suspensions and bacterial recovery measured with and without the use of gentle sonication. Furthermore, survival of bacteria in test and control suspensions was assessed over time. Supernatants of suspensions were analyzed for their element contents using atomic absorption spectrophotometry. The effects of pH, silica, and osmolarity on E faecalis viability were assessed using specifically prepared solutions. RESULTS: BAG preincubated with dentin powder caused a significant (P < .05) decrease in viability compared to pure BAG suspensions. This was not based on adherence of bacteria to solid particles or agglutination of the cells, because sonication did not increase bacterial yields. Hydroxylapatite and decalcified dentin did not increase BAG killing efficacy. The additive effect of BAG + dentin powder was dose dependent, occurred only with solids in suspension, and increased with suspension time. An augmented dissolution of glass components, especially silicon, was measured in BAG + dentin powder compared to pure BAG suspensions or counterparts containing hydroxylapatite or decalcified dentin. High osmolarity per se did not affect E faecalis viability, whereas high pH and silica levels did. CONCLUSION: The observed phenomenon was related to an increased BAG dissolution triggered by dentin powder, causing elevated local pH and silica levels.  相似文献   
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The exposure to Aspergillus organisms/spores is likely common, but disease caused by tissue invasion with these fungi is uncommon and occurs primarily in the setting of immunosuppression. We report a case of rapidly advancing invasive endomyocardial aspergillosis secondary to prolonged usage of multiple broad-spectrum antibiotics in a nonimmunocompromised host. A 36-year-old cotton textile worker presented to our institution with a 3-month history of weight loss and fatigue. He reported receiving prolonged use of multiple broad-spectrum antibiotic treatment. The echocardiogram demonstrated multiple endomyocardial vegetations and a mass in the left atrium. Myocardial biopsy specimen revealed an invasive endomyocardial aspergillosis. The patient was investigated for immune deficiency including HIV, and this workup was negative. Treatment was started with amphotericin B and heparin for presumed left atrial thrombus. The patient died because of a rupture of mycotic aneurysm that resulted in cerebral hemorrhage. This case illustrates the risk of an invasive fungal infection in a nonimmunocompromised host who is a prolonged user of antibiotics in the setting of environmental exposure of opportunistic invasive fungal infections.  相似文献   
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During lower extremity amputation, the objective is to provide a functional residual limb that permits maximum patient mobility and independence. Preservation of length of the fore part of the foot using salvageable tissue from the amputated part in young patients prevents equines deformity and revision of amputation to a higher level. This can be achieved using tissue available from the amputated part. The spare part concept in reconstructive surgery should be integrated into the trauma algorithm to avoid additional donor site morbidity. Reported here is a young adult patient with crush injuries to both feet, which resulted in amputations. A fasciocutaneous flap raised from one extremity was used to facilitate transmetatarsal amputation stump length preservation of the other extremity.  相似文献   
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Rabbits are the experimental animals of choice in many studies including flaps, wounds, and topical trials for new pharmacological agents. Because the topical drugs and other materials used for dressing are irritating to the animal, they tend to remove dressings, bandages, drapes, insensate flaps, and also topical drugs by scratching, licking, and biting if they are within the reach of the animal. In this study, we report an easy to prepare, user-friendly, comfortable, and cheap dressing protector called a dressing shield to prevent these problems.  相似文献   
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A study of the angiographic findings in consecutive civilian patients with cranial gunshot wounds examined in the acute stage has not been done. Most prior clinical studies have evaluated the findings in survivors in the subacute or chronic stages and have often been of war-time casualties. We determined the clinicoradiologic features of six cases of posttraumatic intracranial aneurysm, vascular occlusion, or arteriovenous fistula caused by penetrating missiles among 12 civilian patients who were examined in the acute posttraumatic stage (within 48 hr of injury) during a 1-year period. Three internal carotid/vertebral artery aneurysms, one external carotid artery aneurysm, one combined aneurysm/arteriovenous fistula of the vertebrobasilar circulation, and one cerebral venous occlusion were identified. The 50% overall prevalence of major vascular lesions in this series of civilian patients with penetrating missile injuries examined in the acute stage suggests these injuries are more common than previously suspected. It may indicate that selective cerebral angiography should be considered in the evaluation of the cranial vascular system of such persons.  相似文献   
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PURPOSE: To compare the analgesic effects of dexmedetomidine/morphine with those of tramadol/midazolam in patients undergoing extracorporeal shockwave lithotripsy (ESWL) for urinary calculi. METHODS: Sixty patients were randomized to receive either dexmedetomidine 1 micro g*kg(-1) iv followed by 0.5 micro g*kg(-1)*hr(-1) infusion together with morphine patient-controlled analgesia [(PCA); 2 mg bolus, five minutes lockout, 2 mg*hr(-1) infusion; (Group DEX)], or tramadol 1.5 mg*kg(-1) pre-mixed with midazolam 30 micro g*kg(-1) iv followed by tramadol PCA [20 mg bolus, five minute lockout, 20 mg*hr(-1) infusion; (Group TRA)]. Pain was assessed at baseline and every 15 min thereafter. Patients' and urologist's satisfaction with analgesia and sedation were determined on a seven-point scale ranging from 1 (extremely dissatisfied) to 7 (extremely satisfied). Patient's discharge time was also documented. RESULTS: Visual analogue scale scores over time were consistently lower in Group DEX compared with Group TRA (P = 0.001). Patients' satisfaction with analgesia (5 +/- 1 vs 4 +/- 2, P = 0.012) and with sedation (6 +/- 1 vs 5 +/- 1, P = 0.020), and urologist's satisfaction (6 +/- 1 vs 4 +/- 2, P = 0.001) were all higher amongst Group DEX patients compared with Group TRA. There was no difference between discharge times of patients in Group DEX compared with those in Group TRA [85 (60,115) min vs 65 (40,95) min, P = 0.069]. CONCLUSION: Dexmedetomidine in combination with morphine PCA provided better analgesia for ESWL and was associated with higher patients' and urologist's satisfaction when compared with a tramadol/midazolam PCA combination.  相似文献   
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