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51.
52.
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis.  相似文献   
53.
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction.  相似文献   
54.
Talar dome lesions greater than 1 cm in diameter are often treated with ankle joint mosaicplasty. The purpose of this article is to present the use of a noninvasive ankle distractor that can improve access to the talus when used with a malleolar osteotomy. The use of the distractor allows for graft insertion at a more appropriate angle in relationship to the talar cartilage, avoidance of invasive distractor usage, and potential use of a smaller osteotomy.  相似文献   
55.
OBJECTIVE: Persistent vertigo and imbalance can occur after surgery for vertigo regardless of surgical approach. This study explored for factors affecting outcome of vertigo surgery. STUDY DESIGN: Patient survey and chart review. SETTING: Tertiary referral neurotologic private practice. PATIENTS/INTERVENTION: Of 111 patients (57.7% female; mean age, 52.3 yr), 59 underwent vestibular nerve section (middle fossa, retrolabyrinthine, and translabyrinthine), 25 underwent transmastoid labyrinthectomy, and 27 underwent endolymphatic sac shunt. Eighty-three percent had Ménière's disease. Mean follow-up was 4.3 years. MAIN OUTCOME MEASURES: Primary outcomes included American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) vertigo score and class, number of spells per month, current and change in AAO-HNS disability rating, vertigo and imbalance severity ratings, and frequency of imbalance. RESULTS: Three preoperative factors were consistently related to outcome: AAO-HNS disability rating, imbalance frequency rating, and duration of first symptom ([rho] = 0.19-0.51; all p's < 0.05). Greater disability and more frequent imbalance related to poorer outcome, but longer duration of disease related to better outcome. Presurgery vertigo characteristics were generally not related to outcome. Ménière's patients were more likely to have improvement in imbalance, as were those with no other significant disease and no allergy. The presence of tinnitus in the contralateral ear was associated with poorer outcomes, including a lower rate of results of Classes A and B (p = 0.023). Vertigo as a first symptom and the presence of eye disease also showed relationships to poorer outcome. CONCLUSION: Those rating themselves as more disabled before surgery are less likely to achieve the best outcomes, whereas frequency and severity of preoperative vertigo are not predictive. Several possible prognostic factors were identified that warrant future prospective study.  相似文献   
56.
57.
Isteoporosis-pseudoglioma syndrome (OPPG) is a rare heritable entity that features severe osteoporosis and many variable ophthalmic findings leading to congenital or juvenile blindness. These include microphthalmos, cataracts, bilateral pseudogliomatous retinal detachments, and phthisis bulbi. OPPG is usually not suspected until fractures occur, frequently after seemingly minor trauma. We report the ophthalmic findings of an infant girl with OPPG.  相似文献   
58.
Abstract Prevention of caries in exposed root surfaces constitutes an important clinical problem. It is thus important that clinicians involved with periodontology have an insight into fluoride prophylaxis. The understanding of the cariostatic mechanism of fluoride has improved during recent years. The aim of the present review is to give a short account of the present concept. Calcium fluoride appears to be the only product which is formed on enamel, dentin or cementum during brief topical treatments with fluoride or use of toothpaste containing fluoride. This calcium fluoride is stable in the oral environment: this is contrary to what was believed until recently. The calcium fluoride constitutes a pH-dependant reservoir of fluoride which releases fluoride when pH drops. The practical consequences of this concept is discussed.  相似文献   
59.
OBJECTIVES. The purposes of the study were to assess the potential impact of the North American Free Trade Agreement (NAFTA) on medical care in Mexico and to identify internal measures Mexico could take to increase the benefits and minimize the risks of free trade. METHODS. The dual nature of the health sector is examined; the Mexican, Canadian, and US health care systems are compared; and modes and consequences of international exchange of health services are analyzed. RESULTS. Four issues require immediate attention: accreditation of health care facilities, licensing and certification of professionals, technology assessment, and financial equity. CONCLUSIONS. NAFTA offers opportunities for positive developments in Mexico, provided risks can be anticipated and preventive measures can be taken to avoid negative impacts on the health system. Medical services, like other elements of the Mexican economy, must be modernized to respond to the demands of global competition. The Mexican National Academy of Medicine has recommended to the Mexican government (1) internal strengthening of the Mexican health care system to improve its ability to respond to the new conditions created by NAFTA and (2) a gradual process to facilitate equitable and mutually beneficial interactions among the three countries.  相似文献   
60.
Endocarditis secondary to Hemophilus parainfluenzae is an uncommon entity that appears to be increasing in frequency, perhaps due to improved laboratory isolation techniques. Although controversial, most of the published literature recommends a penicillin, with or without concomitant gentamicin, as definitive therapy. We report the first successful use of the third-generation cephalosporin ceftizoxime in an ampicillin-allergic patient. A 55-year-old white female was hospitalized after 5 days of experiencing fever, chills, nausea, and vomiting. A cardiac echocardiogram revealed a large mitral valve vegetation, and the patient was treated with intravenous ampicillin, gentamicin, and clindamycin. Two weeks after emergency mitral valve replacement the patient developed spiking fevers and a macular, erythematous rash while receiving ampicillin. Ceftizoxime was initiated and continued to complete a 4-week period of intravenous antibiotics. Follow-up at 14 months showed no further evidence of infection. Ceftizoxime appears efficacious in eradicating H. parainfluenzae in patients allergic to penicillin.  相似文献   
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