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Normal and disrupted lumbar longitudinal ligaments: correlative MR and anatomic study 总被引:2,自引:0,他引:2
Grenier N; Greselle JF; Vital JM; Kien P; Baulny D; Broussin J; Senegas J; Caille JM 《Radiology》1989,171(1):197-205
The posterior and anterior longitudinal ligaments of the lumbar spine appear on magnetic resonance (MR) images as thin lines of very low signal intensity in all spin-echo sequences. They cover the periphery of the outer fibers of the anulus fibrosus on sagittal images. The lumbar spine of 17 patients with 19 disk herniations was prospectively evaluated with MR imaging, and these findings were correlated with surgical findings. At surgery the posterior ligament was found to be disrupted in eight cases and intact in 11. Absence of a low-signal peripheral line around the herniated nucleus pulposus (HNP) was the most reliable sign of ligament rupture (no false-negative or false-positive findings). The peripheral line appeared to be interrupted in four cases, two of which were falsely positive. The two false-positive cases were related to a chemical shift artifact between epidural fat and the HNP. Presence of a normal and continuous peripheral line outlining the HNP excluded ligament disruption. The overall sensitivity for detecting disruption was 100%, and the specificity was 78%. 相似文献
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Arianne MJ Elissen Dorijn FL Hertroijs Nicolaas C Schaper Hubertus JM Vrijhoef Dirk Ruwaard 《International journal of integrated care》2016,16(2)
Background:This article presents the design of PROFILe, a studyinvestigating which (bio)medical and non-(bio)medical patient characteristicsshould guide more tailored chronic care. Based on this insight, the project aimsto develop and validate ‘patient profiles’ that can be used inpractice to determine optimal treatment strategies for subgroups of chronicallyill with similar healthcare needs and preferences.Methods/Design:PROFILe is a practice-based research comprising fourphases. The project focuses on patients with type 2 diabetes. During the firststudy phase, patient profiles are drafted based on a systematic literatureresearch, latent class growth modeling, and expert collaboration. In phase 2,the profiles are validated from a clinical, patient-related and statisticalperspective. Phase 3 involves a discrete choice experiment to gain insight intothe patient preferences that exist per profile. In phase 4, the results from allanalyses are integrated and recommendations formulated on which patientcharacteristics should guide tailored chronic care.Discussion:PROFILe is an innovative study which uses a uniquelyholistic approach to assess the healthcare needs and preferences of chronicallyill. The patient profiles resulting from this project must be tested in practiceto investigate the effects of tailored management on patient experience,population health and costs. 相似文献
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LJ Hale GI Welsh CM Perks JA Hurcombe S Moore I Hers MA Saleem PW Mathieson AJ Murphy M Jeansson JM Holly SN Hardouin RJ Coward 《The Journal of pathology》2013,230(1):95-106
Podocytes are crucial for preventing the passage of albumin into the urine and, when lost, are associated with the development of albuminuria, renal failure and cardiovascular disease. Podocytes have limited capacity to regenerate, therefore pro‐survival mechanisms are critically important. Insulin‐like growth factor‐II (IGF‐II) is a potent survival and growth factor; however, its major function is thought to be in prenatal development, when circulating levels are high. IGF‐II has only previously been reported to continue to be expressed in discrete regions of the brain into adulthood in rodents, with systemic levels being undetectable. Using conditionally immortalized human and ex vivo adult mouse cells of the glomerulus, we demonstrated the podocyte to be the major glomerular source and target of IGF‐II; it signals to this cell via the IGF‐I receptor via the PI3 kinase and MAPK pathways. Functionally, a reduction in IGF signalling causes podocyte cell death in vitro and glomerular disease in vivo in an aged IGF‐II transgenic mouse that produces approximately 60% of IGF‐II due to a lack of the P2 promoter of this gene. Collectively, this work reveals the fundamental importance of IGF‐II in the mature podocyte for glomerular health across mammalian species. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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Henk R van Buuren Marijke C Rasch Piet L Batenburg Clemens JM Bolwerk Jan J Nicolai Sjoerd DJ van der Werf Joost Scherpenisse Lidia R Arends Jan van Hattum Erik AJ Rauws Solko W Schalm 《BMC gastroenterology》2003,3(1):1-10
Background
Since esophageal variceal bleeding is associated with a high mortality rate, prevention of bleeding might be expected to result in improved survival. The first trials to evaluate prophylactic sclerotherapy found a marked beneficial effect of prophylactic treatment. These results, however, were not generally accepted because of methodological aspects and because the reported incidence of bleeding in control subjects was considered unusually high. The objective of this study was to compare endoscopic sclerotherapy (ES) with nonactive treatment for the primary prophylaxis of esophageal variceal bleeding in patients with cirrhosis.Methods
166 patients with esophageal varices grade II, III of IV according to Paquet's classification, with evidence of active or progressive liver disease and without prior variceal bleeding, were randomized to groups receiving ES (n = 84) or no specific treatment (n = 82). Primary end-points were incidence of bleeding and mortality; secondary end-points were complications and costs.Results
During a mean follow-up of 32 months variceal bleeding occurred in 25% of the patients of the ES group and in 28% of the control group. The incidence of variceal bleeding for the ES and control group was 16% and 16% at 1 year and 33% and 29% at 3 years, respectively. The 1-year survival rate was 87% for the ES group and 84% for the control group; the 3-year survival rate was 62% for each group. In the ES group one death occurred as a direct consequence of variceal bleeding compared to 9 in the other group (p = 0.01, log-rank test). Complications were comparable for the two groups. Health care costs for patients assigned to ES were estimated to be higher. Meta-analysis of a large number of trials showed that the effect of prophylactic sclerotherapy is significantly related to the baseline bleeding risk.Conclusion
In the present trial, prophylactic sclerotherapy did not reduce the incidence of bleeding from varices in patients with liver cirrhosis and a low to moderate bleeding risk. Although sclerotherapy lowered mortality attributable to variceal bleeding, overall survival was not affected. The effect of prophylactic sclerotherapy seems dependent on the underlying bleeding risk. A beneficial effect can only be expected for patients with a high risk for bleeding. 相似文献998.
Clinical,microbiological and cytomorphometric evaluation of low‐level laser therapy as an adjunct to periodontal therapy in patients with chronic periodontitis 下载免费PDF全文
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GB Boylan L Burgoyne C Moore B O’Flaherty JM Rennie 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(8):1150-1155
Objective: To examine the extent of EEG monitoring in neonatal intensive care units (NICUs), and to survey the level of experience and training of those using it. Study design: A web‐based survey, the link to which was circulated via e‐mail, personal contact, specialist societies and professional groups. Survey data were exported to SPSS for analysis. Results: In total 210 surveys were analysed; 124 from Europe, 54 from the US. Ninety percent of respondents had access to either EEG or aEEG monitoring; 51% had both. EEG was mainly interpreted by neurophysiologists (72%) whereas aEEG was usually interpreted by neonatologists (80%). Only 9% of respondents reported that they felt ‘very confident’ in their ability to interpret aEEG/EEG with 31% reporting that they were ‘not confident’. Half had received no formal training in EEG. Conclusion: Both aEEG and conventional EEG were used extensively in the NICUs surveyed for this study. Most of the survey respondents were not confident in their ability to interpret EEGs despite the fact that they used monitoring routinely. There is an urgent need for a structured and appropriately targeted training programme in EEG methodologies and EEG interpretation for neonatal intensive care unit staff. 相似文献