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991.
Pulse inversion sonography in the early phase of the sonographic contrast agent Levovist: differentiation between benign and malignant focal liver lesions. 总被引:12,自引:0,他引:12
Alexandra von Herbay Christoph Vogt Dieter Hussinger 《Journal of ultrasound in medicine》2002,21(11):1191-1200
OBJECTIVE: To determine whether examination of focal liver lesions by pulse inversion sonography in the early perfusion phase of the contrast agent Levovist (SH U 508A; Schering AG, Berlin, Germany) enables distinction between benign and malignant lesions. METHODS: Seventy-two patients were examined. The cause of the lesion was confirmed by liver biopsy, computed tomography, or both or by hepatic iminodiacetic acid-enhanced scintigraphy. Forty-two patients had malignant liver lesions, and 30 had benign liver lesions. After injection of 2 g of Levovist intravenously, analysis of Levovist arrival was performed by the interval delay imaging technique for 60 seconds. RESULTS: The early arrival of Levovist less than 30 seconds after injection was used as an indicator for malignancy and had specificity of 67% and sensitivity of 60% (P < .05). The central starlike fill-in as a sign for focal nodular hyperplasia had specificity of 100% and sensitivity of 67% (P < .001). The rimlike pattern followed by centripetal fill-in as a sign for hemangioma had specificity of 100% and sensitivity of 18% (P < .01). In contrast, the early diffuse stippled arrival pattern was found in 60% of malignant lesions and also in 33% of cases of focal nodular hyperplasia and in 1 patient with an adenoma. CONCLUSIONS: Analysis of Levovist arrival time cannot distinguish between a malignant or benign lesion in individual cases. However, the central starlike arrival pattern is characteristic of focal nodular hyperplasia. 相似文献
992.
Hans von Baeyer 《Therapeutic apheresis》2002,6(4):320-328
Current reimbursement policy of health insurance for therapeutic plasmapheresis requires proof of efficacy using the concept of evidence-based medicine. The aim of this paper is to review the outcome of plasmapheresis used to treat thrombotic microangiopathy (TMA)-associated syndromes in the last decade to provide scientific evidence to back up reimbursement applications. The strength of evidence of each reviewed study was assessed using the five levels of evidence criteria as defined by the American Society of Hematology in 1996 for assessment of the treatment of immune thrombocytopenia. The level Experimental indication was added for situations where only case reports or small series supported by pathophysiological reasoning are available. The definitions of evidence used in this paper are as follows: Level I, randomized clinical trial with low rates of error (p < 0.01); Level II, randomized clinical trial with high rates of error (p < 0.05); Level III, nonrandomized studies with concurrent control group; Level IV, nonrandomized studies with historical control group; Level V, case series without a control group or expert opinion; and Experimental, case reports and pathophysiological reasoning. The results of this analysis based on the published data is summarized as follows: The indication of plasmapheresis is assigned to Level IV evidence for thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS); cancer/chemotherapy-associated TTP/HUS is assigned to Level V evidence; and TTP/HUS refractory to standard plasma exchange and post-bone marrow transplantation TTP/HUS are assigned to Experimental indication. For both subsets, protein A immunoadsorption is reportedly successful. The other TMA-associated syndromes, hemolysis elevated liver enzymes low platelets and HUS in early childhood, are no indication of plasmapheresis. Two randomized clinical trials were performed in order to demonstrate the superiority of plasma exchange/fresh frozen plasma (PEX/FFP) over plasma transfusion in the management of TTP/HUS. The results prove the greater clinical success of the latter type of plasma administration. Standard PEX/FFP has reduced the mortality of TTP/HUS from 94.5% to 13%. 相似文献
993.
Construct and predictive validity of a self-reported measure of preclinical mobility limitation 总被引:1,自引:0,他引:1
Mänty M Heinonen A Leinonen R Törmäkangas T Sakari-Rantala R Hirvensalo M von Bonsdorff MB Rantanen T 《Archives of physical medicine and rehabilitation》2007,88(9):1108-1113
OBJECTIVES: To validate self-reported preclinical mobility limitation concept and self-report assessment method against muscle power and walking speed, and to study the predictive validity of preclinical mobility limitation with respect to future risk of manifest mobility limitation. DESIGN: Observational prospective cohort study and cross-sectional analysis. SETTING: Research laboratory and community. PARTICIPANTS: A total of 632 community-living (age range, 75-81 y) women and men took part in the baseline assessments and 302 persons in the semi-annual interviews on mobility limitation over 2 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Walking speed, muscle power, and self-reported preclinical and manifest mobility limitation. Preclinical mobility limitation was defined as self-reported tiredness or modification of task performance without task difficulty. At baseline, 4 subgroups were created according to self-reported preclinical mobility limitation in any of 3 mobility tasks (walking 2 km, walking 0.5 km, climbing up stairs): no limitation, preclinical limitation, and minor and major manifest limitation. RESULTS: At baseline, participants with preclinical mobility limitation showed intermediate levels of walking speed and muscle power, compared with those with no limitation or manifest mobility limitation. Participants reporting baseline preclinical mobility limitation had 3- to 6-fold higher age- and sex-adjusted risk of progressing to major manifest mobility limitation during the 2-year follow-up compared with participants with no limitation at baseline, whereas the risk among those with minor limitation at baseline was 14- to 18-fold higher compared with those with no limitation. CONCLUSIONS: The self-report assessment tool proved to be a valid measure to capture the early signs of disability and may serve as an inexpensive tool for identifying those nondisabled persons at high risk for future disability. 相似文献
994.
Kullberg J von Below C Lönn L Lind L Ahlström H Johansson L 《Clinical physiology and functional imaging》2007,27(3):148-153
OBJECTIVES: The first objective was to investigate the correlations between anthropometrical measurements and visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in two cohorts differing in age using magnetic resonance imaging (MRI) as reference. A second objective was to investigate the potential usage of abdominal diameters in practical estimation of adipose tissue compartments using these cohorts. METHODS: Measurements of body mass index, waist circumference, sagittal abdominal diameter (sagittal AD) and transverse abdominal diameter (transverse AD) were obtained from 336 volunteers of age 14-70 years. Manual measurements of VAT and SAT from single slice MRI at the L4-L5 level were used as reference. The abdominal diameters were measured from the MR images. Linear correlations between the anthropometrical measurements and the reference were studied. RESULTS: Sagittal AD showed the strongest correlation to VAT (r >or= 0 x 780, P<0 x 0001) and transverse AD was found to give information about the amount of SAT (r >or= 0 x 866, P<0 x 0001). The ellipse spanned by the sagittal AD and the transverse AD was strongly correlated to the total amount of adipose tissue (r >or= 0 x 962, P<0 x 0001). CONCLUSION: Strong correlations were found between sagittal and transverse abdominal diameters, assessed using MRI, and VAT and SAT, respectively. These results suggest the use of abdominal diameters in practical estimations of VAT and SAT depots. 相似文献
995.
Zhang Dafang Janssen Stein J. Tarabochia Matthew von Keudell Arvind Chen Neal 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(2):359-365
European Journal of Orthopaedic Surgery & Traumatology - The primary objective of this study is to determine whether time from injury to fasciotomy is associated with increased risk for death... 相似文献
996.
Gillian R. Lauder Mark Thomas Britta S. von Ungern‐Sternberg Thomas Engelhardt 《Paediatric anaesthesia》2020,30(3):209-220
Anesthesia for pediatric airway procedures constitutes a true art form that requires training and experience. Communication between anesthetist and surgeon to establish procedure goals is essential in determining the most appropriate anesthetic management. But does the mode of anesthesia have an impact? Traditionally, inhalational anesthesia was the most common anesthesia technique used during airway surgery. Introduction of agents used for total intravenous anesthesia (TIVA) such as propofol, short‐acting opioids, midazolam, and dexmedetomidine has driven change in practice. Ongoing debates abound as to the advantages and disadvantages of volatile‐based anesthesia versus TIVA. This pro‐con discussion examines both volatiles and TIVA, from the perspective of effectiveness, safety, cost, and environmental impact, in an endeavor to justify which technique is the best specifically for pediatric airway procedures. 相似文献
997.
Xingyu Wang Roumen Parapanov Anne Debonneville Yabo Wang Etienne Abdelnour‐Berchtold Michel Gonzalez Fabrizio Gronchi Jean‐Yannis Perentes Hans‐Beat Ris Philippe Eckert Lise Piquilloud Jrme Lugrin Igor Letovanec Thorsten Krueger Lucas Liaudet 《American journal of transplantation》2020,20(4):967-976
Ex vivo lung perfusion (EVLP) with pharmacological reconditioning may increase donor lung utilization for transplantation (LTx). 3‐Aminobenzamide (3‐AB), an inhibitor of poly(ADP‐ribose) polymerase (PARP), reduces ex vivo lung injury in rat lungs damaged by warm ischemia (WI). Here we determined the effects of 3‐AB reconditioning on graft outcome after LTx. Three groups of donor lungs were studied: Control (Ctrl): 1 hour WI + 3 hours cold ischemia (CI) + LTx; EVLP: 1 hour WI + 3 hours EVLP + LTx; EVLP + 3‐AB: 1 hour WI + 3 hours EVLP + 3‐AB (1 mg.mL?1) + LTx. Two hours after LTx, we determined lung graft compliance, edema, histology, neutrophil counts in bronchoalveolar lavage (BAL), mRNA levels of adhesion molecules within the graft, as well as concentrations of interleukin‐6 and 10 (IL‐6, IL‐10) in BAL and plasma. 3‐AB reconditioning during EVLP improved compliance and reduced lung edema, neutrophil infiltration, and the expression of adhesion molecules within the transplanted lungs. 3‐AB also attenuated the IL‐6/IL‐10 ratio in BAL and plasma, supporting an improved balance between pro‐ and anti‐inflammatory mediators. Thus, 3‐AB reconditioning during EVLP of rat lung grafts damaged by WI markedly reduces inflammation, edema, and physiological deterioration after LTx, supporting the use of PARP inhibitors for the rehabilitation of damaged lungs during EVLP. 相似文献
998.
999.
1000.
The COVID-19 pandemic marks an extraordinary global public health crisis unseen in the last century, with its rapid spread worldwide and associated mortality burden. The longevity of the crisis and disruption to normality is unknown. With COVID-19 set to be a chronic health crisis, clinicians will be required to maintain a state of high alert for an extended period. The support received before and during an incident is likely to influence whether clinicians experience psychological growth or injury. An abundance of information is emerging on disease epidemiology, pathogenesis and infection control prevention. However, literature on interventions for supporting the psychological well-being of healthcare workers during disease outbreaks is limited. This article summarises the available management strategies to increase resilience in healthcare workers during the COVID-19 pandemic and beyond. It focuses on self-care and organisational justice. It highlights various individual as well as organisational strategies. With the success of slowing disease spread in many countries to date, and reduced work-load due to limitations on elective surgery in many institutions, there is more time and opportunity to be pro-active in implementing measures to mitigate or minimise potential adverse psychological effects and improve, restore and preserve the well-being of the workforce now and for years to come. The purpose of this review is to review available literature on strategies for minimising the psychological impact of the COVID-19 pandemic on clinicians and to identify pro-active holistic approaches which may be beneficial for healthcare workers both for the current crisis and into the future. 相似文献