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971.
972.
973.
Abdul Ghafur Muhammad Raza Wendy Labbett Anuradha Chawla Colette Smith Siew Lin Ngui Andrew Davenport Anna Maria Geretti 《Nephrology, dialysis, transplantation》2007,22(9):2640-2644
BACKGROUND: It has been proposed that hepatitis C virus (HCV)-infected patients with end-stage renal disease undergoing maintenance haemodialysis may lack HCV antibody (anti-HCV) despite chronic HCV viraemia. This carries important implications for the design of surveillance policies. METHODS: To characterize the prevalence of antibody-negative/RNA-positive HCV infection, patients attending seven haemodialysis units underwent anti-HCV testing using a third-generation assay and HCV RNA testing using real-time PCR. RESULTS: At screening, anti-HCV prevalence was 12/360 (3.3%; 95% CI 1.7-5.8%); 7/12 (58.3%) anti-HCV positive samples were HCV RNA positive. Among anti-HCV-negative samples, 2/348 (0.6%; 95% CI 0.2-2.1%) tested HCV RNA positive (genotype 1a). Retrospective testing of stored sera dated the infections to a period of holiday in the Indian subcontinent. The two infections were unrelated by HCV-NS5B sequencing. Only one of the two newly infected persons showed raised transaminases. Both developed anti-HCV within 8-13 weeks of follow-up. Prospective surveillance of travellers to resource-limited countries returning to the units showed a HCV incidence of 4/153 travel episodes (2.6%; 95% CI 0.7-6.6%) among 131 persons (3.1%; 95% CI 0.8-7.6%). CONCLUSIONS: Among haemodialysis patients in the United Kingdom, antibody-negative/RNA-positive HCV status is associated with newly acquired infection, rather than lack of antibody responses in chronic HCV infection. There is a significant risk of HCV infection associated with travel to resource-limited countries. Given that transaminase levels may be normal, HCV RNA testing is recommended in patients re-entering a dialysis unit following haemodialysis in settings where suboptimal infection control policies pose a risk of exposure to blood-borne viruses. 相似文献
974.
Joseph K. Muhammad Michael A. O. Lewis St. John Crean 《Journal of oral pathology & medicine》2002,31(2):121-124
There have been few reports describing the occurrence of pemphigus vulgaris (PV) during pregnancy. The patient described in this case report is interesting because the PV that developed during her pregnancy was confined to her mouth. It has been suggested that prompt treatment with systemic steroids prevents development of PV in cutaneous tissues. In this case, early control of the condition is believed to have eliminated the need for high dose steroids throughout the remainder of the pregnancy. In addition, this therapeutic approach could have contributed to the birth of a baby free of PV. Resolution of the presenting oral symptoms allowed the mother to resume a normal diet, allaying her anxiety about the possible effects of poor nutritional intake on foetal development. Aspects of clinical management considered in this report include the choice of immunosuppressive therapy and the multidisciplinary care involving both dental and obstetric specialists. 相似文献
975.
Intravascular ultrasonography: validation studies and preliminary intraoperative observations 总被引:1,自引:0,他引:1
R F Neville R W Hobson Z Jamil G B Breitbart R J Anderson A L Bartorelli M B Leon 《Journal of vascular surgery》1991,13(2):274-82; discussion 282-3
Intravascular ultrasonography is emerging as an important imaging modality to assess the presence, distribution, and extent of atherosclerotic vascular disease. To determine the accuracy and clinical utility of intravascular ultrasonography, a flexible catheter-based system was used to generate two-dimensional, cross-sectional vascular images. In 23 arteries of 11 sheep 206 in vivo images demonstrated an echo-free lumen surrounded by three distinct concentric acoustic transitions corresponding to intima, media, and adventitia. Ultrasound measurements of lumen diameter and area correlated significantly with those of corresponding arteriographic measurements obtained by use of digital calipers (r = 0.91, r = 0.86). To evaluate clinical feasibility, intraoperative images (n = 160) were obtained in 10 patients undergoing vascular bypass or hemodialysis access procedures. The images depicted luminal configuration and arterial wall morphologic characteristics. Measurements of lumen diameter and lumen area correlated closely with corresponding intraoperative arteriography (r = 0.81, r = 0.79). The ultrasound images demonstrated arterial stenoses, intimal hyperplasia, intraluminal thrombus, polytetrafluoroethylene graft material, and anastomotic sites. We conclude that flexible catheter-based ultrasonography produces images that accurately demonstrate arterial wall architecture, lumen diameter, and area. Intraoperative application can produce images that provide unique information thus expanding the clinical potential of ultrasonography as a guidance system for vascular procedures. 相似文献
976.
977.
978.
William S. Linn MA Edward B. Rappaport MPH Kiros T. Berhane PhD Tracy M. Bastain MPH Muhammad T. Salam MD MS Frank D. Gilliland MD PhD 《Pediatric pulmonology》2009,44(10):1033-1042
Extended exhaled nitric oxide (eNO) analysis can distinguish proximal and distal airway contributions to FeNO. Thus, it has the potential to detect effects of different environmental influences, allergic phenotypes, and genetic variants on proximal and distal airways. However, its feasibility in field surveys has not been demonstrated, and models for estimating compartmental NO contributions have not been standardized. In this study we verified that extended NO tests can be performed by children in schools, and assessed different analytical models to estimate bronchial flux and alveolar NO concentration. We tested students at a middle school, using EcoMedics NO analyzers with ambient NO scrubbers, at flows of 50 (conventional), 30, 100, and 300 ml/sec, with 2–3 trials at each flow. Data from 65 children were analyzed by two linear and four nonlinear published models, plus a new empirical nonlinear model. Bronchial NO flux estimates from different models differed in magnitude but were strongly correlated (r ≥ 0.95), and increased in subjects with allergic asthma. Alveolar concentration estimates differed among models and did not consistently show the same effects of allergy or asthma. A novel index of nonlinear behavior of NO output versus flow was significantly related to asthma status, and not strongly correlated with bronchial flux or alveolar concentration. Field‐based extended NO testing of children can yield useful information about NO in different regions of the respiratory tract that is not obtainable from conventional FeNO. Extended NO analysis holds promise for investigating environmental and genetic determinants of regional airway inflammatory states. Pediatr Pulmonol. 2009; 44:1033–1042. ©2009 Wiley‐Liss, Inc. 相似文献
979.
Rahman F Banerjee S Ahmed CM Jamil AA Uddin MS Alam S Bhattcharjo B Azam G Sarker H Shamim K Rashid H Diva F Jaman M Hossain Z Ahsan SA Siddique AB Khalil M Haque SS Uddin MJ Hasan KA Khaleque MA Rashid M 《Mymensingh medical journal : MMJ》2007,16(2):197-203
In this ongoing prospective study conducted in University Cardiac Center, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, from July 2004 to January 2006. Fifty (50) patients (mean age 56+/-7.2 years) underwent stentangioplasty were evaluated. The study group of 50 patients consisted of 42 (84%) men and 08 (16%) women. The aim of this study was to evaluate in-hospital success, failure and complications during the procedures. About risk factors 19(38%) had hypertension, 13(26%) were smoker, 11(22%) suffered from diabetes mellitus, 05(10%) had family history of ischaemic heart disease. Average left ventricular ejection fraction was 54+/-7. Target vessel percutaneous coronary angioplasty (PTCA) were done in 61 vessel, intracoronary stent implanted in 58 vessels, direct stenting were done in 35 cases, failed PTCA were in 03(6%) cases and two had dissection. The native vessels had a mean reference diameter of 2.91 mm and their luminal diameter increased significantly after percutaneous coronary intervention (PCI). All the patients were discharged by one to three days of the procedure with improvement of their clinical condition. In conclusion, intracoronary stent deployment in coronary artery stenosis following balloon angioplasty is a valid and beneficial strategy with good in-hospital results. 相似文献
980.
Sleilaty G Yazigi A El Asmar B Hajj-Chahine J Nakad J Madi-Jebara S Aoun-Bacha Z Badaoui G 《Le Journal médical libanais. The Lebanese medical journal》2007,55(2):101-103
Cardiac surgery in patients with previous pneumonectomy is infrequently reported. We report a case of combined coronary artery bypass grafting and aortic valve replacement in a patient with left ventricular ejection fraction less then 35% and a previous right pneumonectomy. All steps in operative management of this rare condition are discussed. 相似文献