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991.
Samonakis DN Cholongitas E Triantos CK Griffiths P Dhillon AP Thalheimer U Patch DW Burroughs AK 《Journal of hepatology》2005,43(6):1091-1093
Immunosuppression is a main determinant for the increased Hepatitis C Virus (HCV) replication after liver transplantation and the accelerated course of recurrent HCV liver disease. We present two patients both with diabetes, renal dysfunction with proteinuria converted to sirolimus therapy, who cleared serum HCV RNA without antiviral treatment. This is a potentially important observation that should stimulate study into factors that may help viral clearance from blood. 相似文献
992.
High-altitude-related pulmonary disease is a spectrum of acute and chronic illnesses with a well-described epidemiology. The risk for these illnesses is related to well-known environmental risk factors and lesser-known but important genetic factors. Prevention of acute high-altitude illness is possible in most visitors from lower elevations. Chronic high-altitude illnesses have an important worldwide impact. 相似文献
993.
Scheibl K Schreyer AG Kullmann F Reichle A Bolder U Schölmerich J Feuerbach S Herfarth H Seitz J 《Investigative radiology》2005,40(3):164-172
OBJECTIVES: We sought to demonstrate the feasibility of depicting gastric tumors using magnetic resonance imaging (MRI) while applying the dark lumen technique. The findings were correlated with conventional gastroscopy. In addition, we evaluated the screening for lymph nodes and liver metastases during the same session to identify potential tumor spread. MATERIALS AND METHODS: The study included 15 patients with known malignant gastric disease. Conventional gastrointestinal endoscopy was performed in all patients as gold standard. All patients were examined with computed tomography for tumor staging. MRI was performed using 1 L of tap water as oral contrast agent for all protocols. The MRI program included an axial T1-weighted (T1w; 2D-FLASH) sequence, an axial STIR and T2w (TSE) sequence, and 2 postcontrast T1w (3D coronal /2D axial FLASH) sequences using 0.2 mmol/kg gadolinium diethylenetriaminepenta-acetic acid as intravenously injected contrast agent. Qualitative analysis and comparison with conventional gastroscopy were performed. RESULTS: The images obtained with the postcontrast 3D coronal T1w-FLASH sequence were the most suitable in identifying gastric tumors. Complete correlation with conventional gastroscopy was achieved in 80% of the cases and partial correlation in 13% of the cases. The same imaging sequence was also appropriate for the evaluation of lymph nodes. For the identification of liver metastases, the images obtained with the axial postcontrast T1w 2D-FLASH sequence provided a higher diagnostic confidence as compared with other imaging protocols. CONCLUSIONS: Applying the dark lumen technique through MRI is suitable for imaging gastric tumors and has the potential to become a "one-stop shopping" method because of the possibility for lymph node evaluation and screening for metastases during the same session based on the same images. 相似文献
994.
PURPOSE: To prospectively assess myocardial perfusion before and after successful intervention in patients suspected of having single-vessel coronary artery disease by using a steady-state free precession (SSFP) perfusion magnetic resonance (MR) imaging sequence. MATERIALS AND METHODS: Local ethics committee approval and informed consent were obtained. Rest-stress perfusion MR imaging studies were performed in 18 patients with coronary artery disease (12 men, six women; mean age, 58.6 years +/- 13.6 [standard deviation]; range, 30-79 years) at 1.5 T with a multisection saturation-recovery SSFP sequence and 0.025 mmol gadopentetate dimeglumine per kilogram of body weight. MR studies were performed before (n = 18), several days after (n = 18), and 8 months after (n = 10) coronary intervention. Nine patients underwent percutaneous transluminal coronary angioplasty (PTCA) alone, and nine patients underwent PTCA with stent placement. Myocardial perfusion reserve index (MPRI) was calculated by dividing results of myocardial perfusion at maximal vasodilation by results at rest. The standard for myocardial perfusion was technetium 99m tetrofosmin single photon emission computed tomography. Statistical significance was tested with univariate variance analysis and Student t tests. RESULTS: In the area of the stenosed vessel, MPRI was 1.04 +/- 0.24 before treatment and 2.18 +/- 0.57 several days afterward (P < .001). In remote areas, MPRI was 2.42 +/- 0.44. In the stent group, MPRI increased by 156%, from 0.99 +/- 0.20 before stent placement to 2.53 +/- 0.53 after (P < .001). Similarly, in the PTCA only group, MPRI increased by 72%, from 1.08 +/- 0.27 before PTCA to 1.87 +/- 0.39 after (P < .001). At follow-up in patients without recurring chest pain, MPRI was 2.14 +/- 0.37 in the area of the treated artery and 2.29 +/- 0.47 in remote areas (P = .06). CONCLUSION: The MPRI, derived from rest-stress examinations, can provide information on success of interventional procedures in stenosed coronary arteries. 相似文献
995.
Angioplasty and stent therapy for stenoses of the renal artery have long been part of the everyday life of interventional radiologists. Newer studies, however, challenge the clinical significance of the method. A decisive advantage of endovascular techniques for the treatment of arterial hypertension as opposed to therapy with modern antihypertensives could not be proven in individual randomized studies, even though blood pressure control was observed to be facilitated by PTA (percutaneous transluminal angioplasty). Renal function often did not show any sustainable improvement following elimination of the renal artery stenosis. However, progression of kidney insufficiency could be slowed down. There is still no general justification from the existing data for the treatment of incidental stenoses. Many questions remain open regarding the technique. Whereas fibromuscular dysplasia can be treated by balloon angioplasty as a general rule, a metallic endoprosthesis must often be used for atherosclerotic stenoses. The outstanding morphologic results of stent therapy in the short and medium term course are often simply used to justify primary stent implantation in ostial stenoses. 相似文献
996.
Hyperbaric Oxygen and Radiotherapy 总被引:3,自引:0,他引:3
Ramona Mayer Martin R. Hamilton-Farrell Adrian J. van der Kleij Jörg Schmutz Gösta Granström Zdzislaw Sicko Yehuda Melamed Ulrich M. Carl K. Axel Hartmann Erik C. Jansen Luciano Ditri Peter Sminia PhD 《Strahlentherapie und Onkologie》2005,181(2):113-123
BACKGROUND: Hyperbaric oxygen (HBO) therapy is the inhalation of 100% oxygen at a pressure of at least 1.5 atmospheres absolute (150 kPa). It uses oxygen as a drug by dissolving it in the plasma and delivering it to the tissues independent of hemoglobin. For a variety of organ systems, HBO is known to promote new vessel growth into areas with reduced oxygen tension due to poor vascularity, and therewith promotes wound healing and recovery of radiation-injured tissue. Furthermore, tumors may be sensitized to irradiation by raising intratumoral oxygen tensions. METHOD: A network of hyperbaric facilities exists in Europe, and a number of clinical studies are ongoing. The intergovernmental framework COST B14 action "Hyperbaric Oxygen Therapy" started in 1999. The main goal of the Working Group Oncology is preparation and actual implementation of prospective study protocols in the field of HBO and radiation oncology in Europe. RESULTS: In this paper a short overview on HBO is given and the following randomized clinical studies are presented: a) reirradiation of recurrent squamous cell carcinoma of the head and neck after HBO sensitization; b) role of HBO in enhancing radiosensitivity on glioblastoma multiforme; c) osseointegration in irradiated patients; adjunctive HBO to prevent implant failures; d) the role of HBO in the treatment of late irradiation sequelae in the pelvic region. The two radiosensitization protocols (a, b) allow a time interval between HBO and subsequent irradiation of 10-20 min. CONCLUSION: Recruitment of centers and patients is being strongly encouraged, detailed information is given on www.oxynet.org. 相似文献
997.
Primary lymphoma of bone: MRI and CT characteristics during and after successful treatment 总被引:3,自引:0,他引:3
Mengiardi B Honegger H Hodler J Exner UG Csherhati MD Brühlmann W 《AJR. American journal of roentgenology》2005,184(1):185-192
OBJECTIVE: Our aim was to describe MRI and CT characteristics of primary lymphoma of bone during and after successful treatment. CONCLUSION: MRI showed a rapid decrease of tumor volume with complete disappearance of the soft-tissue component. Minor signal abnormalities of bone marrow without clinical relevance persisted for up to 2 years. CT showed bone remodeling within months with a persistent architecture similar to that of Paget's disease of the bone. 相似文献
998.
Dental aesthetics, self-awareness, and oral health-related quality of life in young adults 总被引:5,自引:0,他引:5
The aim of the present study was to explore the putative relationship between dental aesthetics and oral health-related quality of life (OHRQoL), taking into consideration the potential direct and moderating influence of private and public self-consciousness. The subjects of this cross-sectional survey were 148 university students. Dental aesthetics were assessed by means of the aesthetic component (AC) of the Index of Orthodontic Treatment Need (IOTN). OHRQoL was estimated using a modification of the scales 'social appearance concern' and 'appearance disapproval', and a novel dental self-confidence scale. In addition, the private and public self-consciousness scales were used. Two-factor analyses of variance were carried out with high and low levels of dental aesthetics and private and public self-consciousness as the independent variables and the OHRQoL scales as the dependent variables. It was found that dental aesthetics had a direct effect on all OHRQoL scale values. Private self-consciousness was related to social appearance concern, while public self-consciousness was associated with both social appearance concern and appearance disapproval. An interaction effect was identified which showed that the impact of dental aesthetics on social appearance concern was stronger in respondents with high private and public self-consciousness than in low scoring subjects. The findings of the study suggest that minor differences in dental aesthetics may have a significant effect on perceived OHRQoL. This effect was more significant in subjects with high self-consciousness. 相似文献
999.
1000.
Comparison of clinical characteristics of influenza and respiratory syncytial virus infection in hospitalised children and adolescents 总被引:1,自引:1,他引:0
While significant morbidity due to respiratory syncytial virus (RSV) infection in the paediatric population has been well acknowledged, little is known about the burden of influenza in primarily healthy children in Europe. In our institution, a University Childrens Hospital in Switzerland, medical staff were encouraged to take nasopharyngeal specimens for multiplex polymerase chain reaction assays for influenza A and B, RSV and several other pathogens from patients hospitalised with respiratory symptoms. We took advantage of this strategy and performed a retrospective study to compare specific characteristics of influenza virus infections with those of RSV during two consecutive winter seasons. Overall, 126 patients were positive for RSV and 60 patients were positive for influenza (type A: 45; type B: 15). The median age of children with RSV, influenza A, and influenza B infection was 4 months; 2 years and 4 months; and 6 years and 2 months, respectively (P<0.001). Fever and cough predominated in children with influenza infection whereas cough, rhinorrhoea, feeding difficulties and dyspnoea were the major symptoms in children with RSV infection. Of patients with influenza, 41% suffered from lower respiratory tract infection compared to 91% of those with RSV infection (P<0.001). Of 60 patients hospitalised with influenza, 12 (20%) experienced febrile convulsions. None of the patients with influenza had been immunised in the respective winter season, although 27% of them had at least one underlying medical condition that would have counted as an indication for immunisation in Switzerland. Conclusion: influenza virus infections, like respiratory syncytial virus infections, are a major cause of hospitalisation in children with respiratory illness during the winter season. Since it is impossible to make an aetiological diagnosis on clinical grounds, it is important to apply specific diagnostic tools in children hospitalised with respiratory illness in order to better characterise the relative burden of disease caused by the respective agents.Abbreviations LRTI lower respiratory tract infection - NPS nasopharyngeal specimens - RAT rapid antigen test - RSV respiratory syncytial virusThis work forms the medical thesis of Susanne Meury at the Medical Faculty, University of Basel, Switzerland. 相似文献