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991.
Chin JL Downey DB Elliot TL Tong S McLean CA Fortier M Fenster A 《The Canadian journal of urology》1999,6(2):720-726
PURPOSE: A three-dimensional ultrasound system (3-D US) was evaluated for its clinical utility in transrectal prostate imaging, in comparison with the current standard 2-dimensional transrectal ultrasound (TRUS) imaging system. METHODS AND MATERIALS: The computer program developed in our laboratory was coupled with a commercially available ultrasound transducer. Geometric validation and volumetric assessment was performed with "stretched-string" wire models and solution-containing balloons respectively. Anatomic correlation of 3-D TRUS images was performed with cadaveric prostates. Intraprostatic lesion localization by 3D-TRUS was assessed clinically by 2 observers in 11 patients prior to radical prostatectomy and the data compared with those yielded by 2-D TRUS. RESULTS: Geometric assessment by 3D TRUS in comparison with the "between strings in the phantom" model (true dimensions) had an error of up to 1.2%. Volume measurement by 3-D TRUS had an error, compared to the true volume, of 0.9%. The correlation coefficient (r) was 0.99985 for the end-firing probe and 0.978 for side firing. The 3-D images provided accurate representation of the true anatomy in the sagittal, transverse and most uniquely, the coronal plane. Two observers achieved better diagnostic accuracies with intraprostatic abnormalities using 3-D instead of standard 2-D TRUS. The negative predictive value and the specificity were improved. CONCLUSION: 3-D TRUS appears to provided accurate representation of the true anatomy with geometric and volumetric validation. Areas of potential clinical application of 3-D TRUS include treatment monitoring with volume measurements and various intervention and therapeutic procedures for both benign and malignant prostatic disorders. 相似文献
992.
Comparison of the antidepressants reboxetine, fluvoxamine and amitriptyline upon spontaneous pupillary fluctuations in healthy human volunteers 总被引:3,自引:0,他引:3
Rationale: Spontaneous fluctuations in the size of the pupil in darkness are a recognised index of ”sleepiness”. Objective: To evaluate the effects of single oral doses of three antidepressants: reboxetine (4 mg), a selective noradrenaline reuptake
inhibitor, fluvoxamine (100 mg), a selective serotonin reuptake inhibitor, and amitriptyline (100 mg), a tricyclic antidepressant
of known sedative property, upon spontaneous pupillary fluctuations in healthy male volunteers (n=16). Methods: Using the recently developed pupillographic sleepiness test (PST), resting pupil diameter was recorded and two measures
of pupillary fluctuations were obtained: total power obtained from a fast Fourier transform and spectral analysis, and the
pupillary unrest index (PUI), a cumulative measure of changes in pupil size. Subjects also rated themselves on a battery of
visual analogue scales for ”alertness”, ”anxiety” and ”contentedness”. Results: Resting pupil diameter was enhanced by reboxetine, but remained unaffected by the other two antidepressants. Amitriptyline,
consistent with its sedative property, increased the total power of pupillary fluctuations and showed a tendency to increase
PUI. These pupillary effects of amitriptyline were paralleled by reduced scores on the ”alertness”, ”contentedness” and ”anxiety”
self ratings. Neither fluvoxamine nor reboxetine affected pupillary fatigue waves or subjective ratings of ”alertness”. Reboxetine
caused a small reduction in subjectively rated ”anxiety”. Conclusions: The mydriatic effect of reboxetine may be due to noradrenaline reuptake blockade in the iris and/or in the central nervous
system. The enhancement of pupillary fatigue waves by the sedative antidepressant amitriptyline, but not by the non-sedative
antidepressants fluvoxamine and reboxetine, indicates that the PST is a suitable quantitative objective test for the detection
of drug-induced changes in the level of arousal.
Received: 9 July 1999 / Final version: 26 October 1999 相似文献
993.
Background/ObjectivesTo determine the predictors of narrow angle detection in a United States population-based cohort.Materials and methodsThis was a retrospective cohort study using the Massachusetts All-Payer Claims Database. Demographic information of all patients and eye care provider information during the years 2011–2015 were extracted from Massachusetts All Payers Claims Data. All payers who received eye care during 1/1/2012–12/31/2015 without any previous eye visit during 2011 were included in the analyses. Laser peripheral iridotomy was identified by Current Procedural Terminology code 66761. Narrow angle detection was defined as the diagnosis of narrow angles by diagnosis code followed by a laser peripheral iridotomy procedure. Different predictors of narrow angle detection were evaluated using Kaplan–Meier curves with the log rank and Cox regression modeling.ResultsA total of 1,082,144 patients were included. The hazard ratio of narrow angle detection increased with age compared to the reference group of 0–10 years: 21–30 years of age (hazard ratio = 4.5), 31–40 (10.5), 41–50 (27.9), 51–60 (46.1), 61–70 (68.4), 71–80 (56.8) (all p < 0.0002), was 1.47 times higher in women and 1.85 times higher if evaluated by ophthalmologists compared to optometrists, after controlling for provider × time interaction.ConclusionOlder age and female sex are associated with narrow angles. The rate of narrow angle detection was significantly higher if patients are seen by ophthalmologists compared to optometrists only. Evaluation with an ophthalmologist may be important for patients at high risks for developing primary angle closure glaucoma.Subject terms: Physical examination, Health occupations, Epidemiology 相似文献
994.
995.
Aaron Wallace Timothy E. Cooney Richard Englund John D. Lubahn 《Journal of orthopaedic research》2011,29(9):1437-1442
This study examined the impact of an interleukin‐6 (IL‐6) knockout on fracture healing in terms of histological and biomechanical responses. Following IACUC approval, tibial fractures were produced in 4‐ to 6‐week‐old IL‐6 knockouts (n = 35) and wild‐type mice (n = 36) and harvested along with contralateral limbs at 2 and 6 weeks postsurgery. Histology quantified stage of healing, lymphocyte infiltration, TRAP+ cells, and osteocalcin deposition. Bend testing established maximum load and stiffness. Based on normality assessments, Mann–Whitney U or independent t‐tests were used for data analysis using a p‐value threshold of 0.05. Stage of healing, lymphocyte infiltration, and osteocalcin deposition were similar for all time points (p ≥ 0.243). TRAP+ cell counts were reduced approximately 10‐fold in the knockout at 2 weeks (p = 0.015) but were similar at 6 weeks (p = 0.689). Force‐to‐failure in knockouts was approximately 40% that of wild‐type mice at 2 weeks (p = 0.040) but similar at 6 weeks (p = 0.735). Knockout bone was about 25% less stiff at 2 weeks but approximately 60% stiffer at 6 weeks (p ≥ 0.110). The absence of IL‐6 during early fracture healing significantly reduced osteoclastogenesis and impaired callus strength. By 6 weeks, most histological and biomechanical parameters were similar to fractures in wild‐type bone. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1437–1442, 2011 相似文献
996.
997.
Thomas Gilmore Gerald F. O’Malley Wayne Bond Lau David R. Vann Adam Bromberg Aaron Martin Andrea Gibbons Evan Rimmer 《Journal of medical toxicology》2013,9(1):16-20
Lead-contaminated ceramics can be a clinically significant source of lead poisoning, with the potential to cause illness in children and adults; one death in a child has been described. We hypothesized that the prevalence of lead-contaminated ceramics would be higher within Chinatown versus outside of Chinatown. The study was a prospective observational cross-sectional study. Two areas were defined geographically as being within and outside of Philadelphia''s Chinatown, and a predefined number of items were purchased in each area. Each item was screened for lead utilizing a colorimetric testing swab. Positive items were leached for lead using the ASTM C738-94 protocol for lead level quantification. The primary outcome was the prevalence of ceramics not compliant with the FDA standard for leachable lead within and outside of Philadelphia''s Chinatown. A total of 132 items were purchased, 46 outside of and 86 within Chinatown. More lead-positive items originated within Chinatown than outside of Chinatown [five positive items, 5.8 % prevalence within Chinatown (95 % confidence interval, CI, 2.5–12.9 %), and zero positive, 0 % prevalence outside of Chinatown (95 % CI 0–7.5 %)]. However, this difference was not found to be statistically significant (P = 0.1624). The leachable lead-positive items were up to 40-fold the acceptable FDA levels. Testing a larger number of items may demonstrate a significant source of lead exposure. 相似文献
998.
999.
Sarah Cusworth Walker Suzanne E.U. Kerns Aaron R. Lyon Eric J. Bruns T.J. Cosgrove 《The Journal of adolescent health》2010,46(3):251-257
PurposeThe purpose of this study was twofold: (1) to examine the effects of School-Based Health Center (SBHC) use on academic outcomes for high school students, using a well-controlled, longitudinal model, and (2) to examine whether SBHC medical and mental health service use differentially impacts academic outcomes.MethodsAnalyses used a latent variable growth curve modeling approach to examine longitudinal outcomes over five school semesters for ninth grade SBHC users and nonusers from Fall 2005 to Fall 2007 (n = 2,306). Propensity score analysis was used to control for self-selection factors in the SBHC user and nonuser groups.ResultsResults indicated a significant increase in attendance for SBHC medical users compared to nonusers. Grade point average increases over time were observed for mental health users compared to nonusers. Discipline incidents were not found to be associated with SBHC use.ConclusionsSBHC use was associated with academic improvements over time for a high-risk group of users. The moderating effect of type of use (medical and mental health) reinforces the importance of looking at subgroups when determining the impact of SBHC use on outcomes. 相似文献
1000.