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排序方式: 共有1194条查询结果,搜索用时 15 毫秒
1.
Oluwatobi O Onafowokan Nicola F. Fine Francis Brooks Oliver M. Stokes Timothy WR Briggs Mike Hutton 《European spine journal》2020,29(3):564-578
To examine the strength of evidence available for multiple facet joint injections (FJIs) and medial branch blocks (MBBs), and to report on the variations in the NHS England framework using the getting it right first time (GIRFT) data. Systematic review using patient, intervention, comparison, outcome and study strategy. The literature search using Cochrane, MEDLINE and EMBASE databases using MeSH terms: lumbar spine, spinal injection and facet joint (“Appendix A”). Three studies were identified that investigated the efficacy of multiple FJIs or MBBs. None of these studies reported sustained positive outcomes at long-term follow-up. There is a paucity of levels I and II evidence available for the efficacy of multiple FJIs and MBBs in treating low back pain. GIRFT data show a high degree of variation in the use of multiple FJIs, which would not be supported by the literature. These slides can be retrieved under Electronic Supplementary Material. 相似文献
2.
Joshua Hiatt Godfrey Mukwada Michael Barnes Hans Lynggaard Riis Du Huynh Pejman Rowshanfarzad 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2018,41(4):945-955
Multileaf-collimator (MLC) defined small fields in radiotherapy are used in high dose, ultra-conformal techniques such as stereotactic radiotherapy and stereotactic radiosurgery. Proximity to critical structures and irreversible damage arising from inaccurate delivery mean that correct positioning of the MLC system is of the utmost importance. Some of the existing techniques for MLC positioning quality assurance make use of electronic portal imaging device (EPID) images. However, conventional collimation verification algorithms based on the full width at half maximum (FWHM) fail when applied to small field images acquired by an EPID due to overlapping aperture penumbrae, lateral electron disequilibrium and radiation source occlusion. The objective of this study was to investigate sub-pixel edge detection and other techniques with the aim of developing an automatic and autonomous EPID-based method suitable for MLC positional verification of small static fields with arbitrary shapes. Methods investigated included derivative interpolation, Laplacian of Gaussian (LoG) and an algorithm based on the partial area effect hypothesis. None of these methods were found to be suitable for MLC positioning verification in small field conditions. A method is proposed which uses a manufacturer-specific empirically modified FWHM algorithm which shows improvement over the conventional techniques in the small field size range. With a measured mean absolute difference from planned position for Varian linacs of 0.01?±?0.26 mm, compared with the erroneous FWHM value of 0.70?±?0.51 mm. For Elekta linacs the proposed algorithm returned 0.26?±?0.25 mm, in contrast to the FWHM result of 1.79?±?1.07 mm. 相似文献
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Evaluation of collagen/hydroxylapatite for augmenting deficient alveolar ridges: a preliminary report 总被引:2,自引:0,他引:2
D R Mehlisch T D Taylor D G Leibold R Hiatt D E Waite P D Waite D M Laskin S T Smith M M Koretz 《Journal of oral and maxillofacial surgery》1987,45(5):408-413
A multicenter study was undertaken to evaluate a new alveolar ridge augmentation material composed of purified fibrillar collagen and particulate hydroxylapatite (PFC/HA). In a study of 77 patients and 99 reconstructed ridges, this material provided superior handling properties over HA alone as evidenced by its ease of surgical placement and manipulation, and the rarity of particle migration or displacement. Moreover, the rapid development of ridge firmness and stability allowed for the loading of dentures within three to six weeks. Prosthodontist evaluations and surveys of patient satisfaction showed great satisfaction with denture fit, comfort, esthetics, speech, and ability to masticate. 相似文献
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During an 18-month period, 148 children examined in the emergency room at the University of Mississippi Medical Center were suspected of having been the victims of child abuse. Physical abuse was suspected in 42.5%, sexual abuse in 38.5%, and neglect in 24.0%. The high prevalence of sexual abuse, particularly rape, and the severity of the various injuries associated with physical abuse indicate the need for primary prevention. 相似文献
8.
A new suction catheter, designed to deliver alternately oxygen or suction, prevented episodes of hypoxia and hyperoxia in a group of infants during endotracheal suctioning. Twenty infants received both conventional endotracheal suctioning and suctioning by the new catheter. The infants had a maximal change from a presuctioning transcutaneous oxygen (PtcO2) of 12 +/- 8 torr and required 3.1 +/- 2 min to regain their presuctioning oxygenation level compared to a maximal change of 21 +/- 10 torr (p less than .05) and a stabilization time of 5.3 +/- 2.6 min (p less than .05) in the conventionally treated group. Three study infants experienced an abnormal PtcO2 (either less than 40 or greater than 90 torr), while 13 control infants suffered these abnormalities (p less than .01). The use of this new suction device effectively reduced the exposure of this group of infants to episodes of aberrant oxygen states and allowed for a shorter recovery time. 相似文献
9.
Percutaneous radiofrequency ablation of hepatocellular carcinoma as a bridge to liver transplantation 总被引:28,自引:0,他引:28
Lu DS Yu NC Raman SS Lassman C Tong MJ Britten C Durazo F Saab S Han S Finn R Hiatt JR Busuttil RW 《Hepatology (Baltimore, Md.)》2005,41(5):1130-1137
Orthotopic liver transplantation (OLT) can be a definitive treatment for patients with hepatocellular carcinoma (HCC). Prolonged waiting times for cadaveric livers, however, may lead to dropout from the waiting list or worsened post-OLT prognosis as a result of interval tumor progression. Percutaneous radiofrequency ablation (RFA) is widely used for local control of small unresectable HCC, but its pretransplant role remains unclear. We studied the outcome of 52 consecutive patients accepted for OLT bearing 87 HCC nodules and treated with percutaneous RFA. On initial staging, the tumor burden exceeded the Milan criteria in 10 patients. Complete tumor coagulation was observed in 74 of 87 (85.1%) nodules based on postablation imaging. After a mean of 12.7 months (range: 0.3-43.5) on the waiting list, 3 of 52 patients (5.8%) had dropped out due to tumor progression. Forty-one patients had undergone transplantation, with 1- and 3-year post-OLT survival rates of 85% and 76%, respectively. No patient developed HCC recurrence. There were three major complications in 76 RFA procedures (hepatic arterial hemorrhage, small bowel perforation, and liver decompensation salvaged by OLT), without resultant death or dropout. In conclusion, percutaneous RFA is an effective bridge to OLT for patients with compensated liver function and safely accessible tumors. Tumor-related dropout rate and post-OLT outcome compared favorably with published controls of patients with early-stage disease. This can be attributed to the efficacy of RFA in producing local cure or curbing tumor progression during the waiting period. 相似文献
10.
Alena V Savonenko Tatiana Melnikova Andrew Hiatt Tong Li Paul F Worley Juan C Troncoso Phil C Wong Don L Price 《Neuropsychopharmacology》2012,37(1):261-277
Over the past three decades, significant progress has been made in understanding the neurobiology of Alzheimer''s disease. In recent years, the first attempts to implement novel mechanism-based treatments brought rather disappointing results, with low, if any, drug efficacy and significant side effects. A discrepancy between our expectations based on preclinical models and the results of clinical trials calls for a revision of our theoretical views and questions every stage of translation—from how we model the disease to how we run clinical trials. In the following sections, we will use some specific examples of the therapeutics from acetylcholinesterase inhibitors to recent anti-Aβ immunization and γ-secretase inhibition to discuss whether preclinical studies could predict the limitations in efficacy and side effects that we were so disappointed to observe in recent clinical trials. We discuss ways to improve both the predictive validity of mouse models and the translation of knowledge between preclinical and clinical stages of drug development. 相似文献