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1.
Andrew M Briggs John D Wark Susan Kantor Rayson Teh Alison M Greig Nicola L Fazzalari Kim L Bennell 《Journal of clinical densitometry》2005,8(3):314-319
Analysis of apparent bone mineral density (BMD) in the lumbar spine is commonly based on anteroposterior (AP) scanning using dual-energy X-ray absorptiometry (DXA). Although not widely used, clinically important information can also be derived from lateral scanning. Vertebral bone density, and therefore strength, can may vary in different subregions of the vertebral body. Therefore, subregional BMD measurements might be informative about fracture risk. However, the intrarater and interrater precision of in vivo subregional BMD assessments from lateral DXA remains unknown. Ten normal, young (mean: 24 yr) and 10 older (mean: 63 yr) individuals with low BMD were scanned on one occasion using an AP/lateral sequence. Each lateral scan was reanalyzed six times at L2 by three raters to determine the intrarater and interrater precision in selecting seven regions of interest (subregions). Precision was expressed using percentage coefficients of variation (% CV) and intraclass correlation coefficients (ICC). Intrarater precision ranged from ICC(1,1) 0.971 to 0.996 (% CV: 0.50-3.68) for the young cohort and ICC(1,1) 0.934 to 0.993 (% CV: 1.46-5.30) for the older cohort. Interrater precision ranged from ICC(2,1) 0.804 to 0.915 (% CV: 1.11-2.35) for the young cohort and ICC(2,1) 0.912 to 0.984 (% CV: 1.85-4.32) for the older cohort. Scanning a subgroup of participants twice with repositioning was used to assess short-term in vivo precision. At L2, short-term in vivo precision ranged from ICC(1,1) 0.867 to 0.962 (% CV: 3.38-9.61), at L3 from ICC(1,1) 0.961 to 0.988 (% CV: 2.02-5.57) and using an L2/L3 combination from ICC(1,1) 0.942 to 0.980 (% CV: 2.04-4.61). This study demonstrated moderate to high precision for subregional analysis of apparent BMD in the lumbar spine using lateral DXA in vivo. 相似文献
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J L Woolley G R Barker W K Jacobsen G A Gingrich S C Stewart B A Briggs R D Martin R A Melashenko 《Critical care medicine》1988,16(1):48-51
The ability of the calcium entry blocker verapamil to ameliorate the effects of renal ischemia was studied in ten sheep. Postanesthesia, bilateral cutaneous ureterostomies were placed in each sheep to facilitate urine collection and analysis. Both kidneys were made ischemic for one hour by occluding each renal artery. However, immediately before occlusion of the right renal artery, 0.05 mg/kg of verapamil was injected into the artery. Comparison of urinary creatinine excretion and urine volume for 72 h after reversal of ischemia demonstrated that those kidneys pretreated with verapamil had greater functional preservation (p less than .05). In this study, verapamil appeared to provide protection against renal damage after an ischemic insult. 相似文献
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S Gunasti† SS Marakli† I Tuncer‡ N Ozpoyraz§ VL Aksungur† 《Journal of the European Academy of Dermatology and Venereology》2007,21(6):811-817
BACKGROUND: We have seen several patients with itchy lichenified plaques located bilaterally on the elbows and/or knees and have named this condition 'psoriatic neurodermatitis' (PN). OBJECTIVE: The purpose of this study was to compare clinical and histopathological characteristics of these patients to those of patients with typical lichen simplex chronicus (LSC). METHODS: Nineteen patients with PN and 34 patients with typical LSC were included. Besides clinical dermatological evaluation, the prick test was carried out on 49 patients; the Phadiatop test on 40 patients; the patch test with European standard series on 47 patients; histopathological evaluation on 39 patients; and clinical psychiatric examination on 38 patients. RESULTS: Almost exclusively, PN was seen in females and was located on the extremities. It caused more plaques than typical LSC did. In PN, the plaques were smaller, sharper, more keratotic and less excoriated, and had fewer lichenoid papules around them. Itching was usually more severe in the evening, while resting and in a hot environment in typical LSC, but not in PN. In plaques of PN, microabscesses in the horny layer, hypogranulosis, regular acanthosis and thinning of the suprapapillary plates were more frequent, and hyperpigmentation in the basal layer was less. In patients with PN, depressive disorder was found more frequently; and generalized anxiety disorder or psychosomatic characteristics, less. There were no significant differences in the results of prick, Phadiatop and patch tests between patients with PN and those with typical LSC. CONCLUSION: In our opinion, it is most likely that the so-called PN is itchy psoriasis superimposed by LSC. 相似文献
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Specific MR imaging of human lymphocytes by monoclonal antibody-guided dextran-magnetite particles. 总被引:4,自引:0,他引:4
J W Bulte Y Hoekstra R L Kamman R L Magin A G Webb R W Briggs K G Go C E Hulstaert S Miltenyi T H The 《Magnetic resonance in medicine》1992,25(1):148-157
Human lymphocytes were labeled with biotinylated anti-lymphocyte-directed monoclonal antibodies, to which streptavidin and subsequently biotinylated dextran-magnetite particles were coupled. This labeling resulted in a strong and selective negative contrast enhancement of lymphocyte suspensions at 2.0 T, caused predominantly by the specific increase of R2 with a small but significant specific increase of R1. The R1 was found to decrease with increasing field strength. The immunolabeling procedure described here may be used for the selective signal depletion of target cells in MR imaging. 相似文献
7.
Shelby D Reed Peter W Dillingham Andrew H Briggs David L Veenstra Sean D Sullivan 《Medical decision making》2003,23(3):252-264
Pharmacy and therapeutics committees commonly cite a lack of generalizability as a reason for not incorporating cost-effectiveness information into decision making. To address this concern, many committees undertake site-specific economic evaluations, which are often limited by small sample sizes and nonrandomized designs. We show how 2 complementary approaches were used to minimize these limitations in an economic evaluation of abciximab at 1 institution. Using a propensity score methodology, we selected patients who did not receive abciximab for the comparison cohort. Then, we adopted a Bayesian, hierarchical, random-effects model to integrate site-specific and clinical trial data. We applied the posterior distributions of effectiveness with local cost data in a traditional decision-analytic model. In 74% of the simulations, abciximab was cost-effective at 1 institution at the $50,000 per life year saved threshold, assuming a 50:50 split of patients undergoing coronary stenting and angioplasty. Among patients undergoing coronary stenting, the cost-effectiveness ratio of the addition of abciximab was at or below the $50,000 per life year saved threshold in 66.0% of the simulations. 相似文献
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Marc Philippon Mara Schenker Karen Briggs David Kuppersmith 《Knee surgery, sports traumatology, arthroscopy》2007,15(7):908-914
Femoroacetabular impingement (FAI) occurs when an osseous abnormality of the proximal femur (cam) or acetabulum (pincer) triggers
damage to the acetabular labrum and articular cartilage in the hip. Although the precise etiology of FAI is not well understood,
both types of FAI are common in athletes presenting with hip pain, loss of range-of-motion, and disability in athletics. An
open surgical approach to decompressing FAI has shown good clinical outcomes; however, this highly invasive approach inherently
may delay or preclude a high level athlete’s return to play. The purpose of this study was to define associated pathologies
and determine if an arthroscopic approach to treating FAI can allow professional athletes to return to high-level sport. Hip
arthroscopy for the treatment of FAI allows professional athletes to return to professional sport. Between October 2000 and
September 2005, 45 professional athletes underwent hip arthroscopy for the decompression of FAI. Operative and return-to-play
data were obtained from patient records. Average time to follow-up was 1.6 years (range: 6 months to 5.5 years). Forty two
(93%) athletes returned to professional competition following arthroscopic decompression of FAI. Three athletes did not return
to play; however, all had diffuse osteoarthritis at the time of arthroscopy. Thirty-five athletes (78%) remain active in professional
sport at an average follow-up of 1.6 years. Arthroscopic treatment of FAI allows professional athletes to return to professional
sport. 相似文献