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991.
Claudia E E Noffke Erich J Raubenheimer Ntombizonke J Chabikuli Michael M R Bouckaert 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(1):101-109
OBJECTIVE: The purpose of the study was to analyze the clinical and radiographic features of central odontogenic myxomas (OM) of the jaws diagnosed over 23 years in a black South African patient sample. STUDY DESIGN: Records of 30 cases of OMs with radiographs of diagnostic quality were retrieved from 52 cases of histopathologically verified OMs from the archives of the Oral Health Center at the University of Limpopo, South Africa. The age, sex, size, location, and radiographic features were compared with the literature. RESULTS: The study consisted of 21 females and 9 males. The correlation between age and size of the tumor was found to be statistically significant (P = .004). Septa were shown to be either reorientated cortical bone or sheets of dense fibrous connective tissue. Indistinct borders mimicked malignancy. The most common radiographic feature was the tennis-racket appearance. CONCLUSIONS: Variations in radiographic presentation make a radiological differential interpretation of OM challenging because the radiographic features overlap with those of other benign and malignant neoplasms. 相似文献
992.
K Parsi T Exner D E Connor D D F Ma J E Joseph 《European journal of vascular and endovascular surgery》2007,34(6):731-740
OBJECTIVES: To investigate the in vitro effects of Sodium Tetradecyl Sulphate (STS) and Polidocanol (POL) on clotting tests, clotting factors, platelets and microparticles. MATERIALS AND METHODS: Platelet rich (PRP) and platelet poor (PPP) plasmas were incubated with varying concentrations of STS and POL. Clotting tests, platelet/plasma turbidity, and microparticle studies were performed. Specimens were mixed with individual factor deficient plasmas and clotting factor activities were studied. RESULTS: STS at high concentrations (>0.3%) destroyed platelets, microparticles and the clotting factors V, VII and X. It prolonged all clotting tests including prothrombin time (PT), activated partial thromboplastin time (APTT), non-activated partial thromboplastin time (NAPTT), thrombin time (TT), factor Xa clotting time (XACT) and surface activated clotting time (SACT). Higher concentrations of POL were required to achieve some anticoagulant activity. Low sclerosant concentrations shortened XACT and SACT, and induced release of procoagulant platelet derived microparticles. Increased exposure time resulted in increased procoagulant activity. STS at concentrations higher than 0.5% precipitated a complex containing apolipoprotein b and fibrinogen. CONCLUSIONS: Detergent sclerosants affect the clotting mechanism by interfering with clotting factor activities, procoagulant phospholipids and platelet derived microparticles. STS has more anticoagulant activity than POL in high concentrations. Low concentration sclerosants demonstrate procoagulant activity. 相似文献
993.
BACKGROUND: According to the Center for Disease Control and Prevention (CDC), an estimated 30 million people ride horses each year in the United States. Horseback riding related injuries are common, with an estimated 50,000 emergency room visits annually. The popularity of recreational horseback riding has increased in South Florida and the incidence of associated traumatic injuries is a reflection of this. MATERIAL AND METHODS: Retrospective review of patients admitted to a state designated Level I trauma center that sustained horseback riding associated injuries between January 2000 and December 2003. Information extracted from the Trauma Center's data base included demographics, mechanism of injury and toxicology screening. RESULTS: During the review period, twenty-seven patients were identified. There were 12 men and 15 women. The average age was 36 years. The injuries occurred during pleasure riding in 23 patients and thoroughbred related activities in 4 patients. Multiple severe injuries were common and documented in 24 patients. All patients required hospitalization with an average stay of 5 days. Five patients had a positive toxicology screen on admission. No deaths were documented in this review. CONCLUSION: Horseback riding related injuries tends to be serious. Alcohol and recreational drugs may contribute to exacerbate the extent of these injuries. The use of proper protective equipment, instructions for safe riding, and discouraging drug and alcohol use during riding activities should be emphasized. 相似文献
994.
R. A. Wolfe F. B. LaPorte A. M. Rodgers E. C. Roys G. Fant A. B. Leichtman 《American journal of transplantation》2007,7(S1):1404-1411
Turndowns of offers of deceased donor kidneys for transplantation can contribute to inefficiencies in the organ distribution system and inequality in access to donated organs. Match run data were obtained for 4967 'good' kidneys placed and transplanted in 2005 after fewer than 50 offers. These kidneys were not recovered from donation after cardiac death or expanded criteria donors, or from donors with a history of substance abuse. On average, these good kidneys were not accepted until after seven offers to candidates and after offers to 2.4 programs. Models for the likelihood of acceptance found several donor and candidate characteristics to be significantly related to acceptance rates (p < 0.05). After accounting for these variables, there remained 2- to 3-fold differences among transplant programs in acceptance rates. These models could be used to identify kidney transplant centers with exceptional acceptance practices. Several strategies might be employed to increase acceptance rates for good organs. 相似文献
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The case record of a seventy-three year old man with congenital dextrocardia and situs inversus viscerum complicated by hypertension, coronary artery disease and myocardial infarction is presented. Electrocardiographic recordings of the limb leads, with and without reversal of the arm lead wires, and of the precordial leads of the V series derived from both right and left chest areas are presented. In this instance the electrocardiographic findings in precordial leads taken over the right chest point to fresh anteroseptal infarction; those leads recorded from the left chest were not informative. This serves to emphasize the fact that precordial leads should be recorded from the right side of the chest rather than the left in order that the exploring precordial electrode may overlie the area of cardiac damage, and thus manifest maximal changes in the electrocardiogram. We agree that the electrocardiogram may best be interpreted by application of the usual criteria to the limb leads taken with the arm lead wires reversed although in this case the limb leads yielded no information of diagnostic significance. 相似文献