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991.
Jack E Richman Kathleen Golden McAndrew Donald Decker Stephen C Mullaney 《Optometry》2004,75(3):175-182
BACKGROUND: The Drug Evaluation and Classification (DEC) program was developed to detect, arrest, and convict drivers impaired by drugs other than alcohol. The DEC program is a training program designed to prepare police officers and other qualified persons to serve as Drug Recognition Experts (DREs). PURPOSE: The purposes of this study were: (1) to determine normative values and ranges for pupillary responses using the specific DEC program protocols for pupil testing in nonimpaired persons, and (2) to appraise the suitability of the 3.0- mm to 6.5-mm pupil range as a potential sign of impairment under three conditions. METHODS: Trained DRE officers measured pupi sizes using standardized DEC protocols. Pupil measurements were taken under three light levels: room light, near-total darkness, and direct light. The subjects were 250 volunteers, with an average age of 29.2 years (+/-6.1). All subjects were healthy, nonimpaired, and free of visual, and/or neurological problems. RESULTS: For each pupil measured (N= 500), the mean (SD) for each of the three test conditions were: room light 3.86 (0.93) mm; near-total darkness 6.41(1.55) mm; and direct light 3.35 (0.72) mm. CONCLUSIONS: This study determined normative values and potential ranges for pupillary responses using the specific DEC program protocols for pupil testing in non-impaired persons. When the presently approved DEC program pupil size range (3.0 to 6.5 mm) is compared with the results of this study, it appears that the DEC range for pupil size might be too sensitive. However, when determining impairment related to drug(s), the DRE reviews the results of all tests and draws a conclusion based on the totality of the evidence, not only on a variation in the pupil size. 相似文献
992.
Kish L. Golden Heidi L. Collins Alfred M. Loka 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(8):593-604
Gender disparities in cardiac function have been described. Yet the extent to which gender related differences in cardiac performance are due to the presence of sex-specific biological factors are unclear. We used a longitudinal study aimed at examining whether castration and androgen replacement affects cardiac performance in conscious adult male rats. Adult male rats were implanted with Piezoelectric transit-time gauges and radio telemetry devices to measure regional myocardial segment length and hemodynamic variables before and after castration and after androgen replacement. Androgen withdrawal accelerated average heart rates by 7% (p = 0.010). Heart rate was lowered to intact values when androgens were restored to normal physiological levels (p = 0.004). Mean arterial pressure was not affected by androgen deprivation and androgen replacement. However, androgen withdrawal produced a 40% decrease in the velocity of circumferential shortening and a 46% reduction in the rate of myocardial relaxation. Androgen supplementation completely restored contractile function. These results provide the first evidence that androgen withdrawal and androgen replacement produces dramatic alterations on cardiac performance in conscious animals and demonstrates the significance of androgens as a cardioregulatory hormone in males. Sex steroids are likely contributors to gender-related differences in cardiac function. 相似文献
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A longitudinal study of serotonergic function in depression. 总被引:1,自引:0,他引:1
Robert N Golden Amy Durr Heine R David Ekstrom Joseph M Bebchuk Martha E Leatherman James C Garbutt 《Neuropsychopharmacology》2002,26(5):653-659
Several reports have described abnormal neuroendocrine responses to serotonergic challenge tests in depression, but few have studied depressed patients followed longitudinally. In order to determine whether blunted prolactin responses to clomipramine challenge is a "state" vs. "trait" marker in depression, we applied this challenge paradigm to 20 patients with Major Depression prior to treatment and at three additional time points following response to desipramine: at the completion of acute treatment; at the end of the continuation phase of treatment; and after a minimum of three weeks "washout" following the discontinuation of treatment. The prolactin response to clomipramine challenge was blunted in depressed patients compared with matched healthy control subjects, at each time point over the longitudinal course of their illness and recovery. Challenge test results in depressed patients did not change after response to acute desipramine therapy, at the conclusion of the continuation phase of treatment, or while in a medication-free state of remission. Blunted prolactin response to clomipramine challenge persists in depressed patients after recovery from acute illness, and may reflect an underlying biological vulnerability. 相似文献
995.
Fairman RM Velazquez OC Carpenter JP Woo E Baum RA Golden MA Kritpracha B Criado F 《Journal of vascular surgery》2004,40(6):1074-1082
OBJECTIVE: This study was undertaken to determine whether a complicated aortic neck is associated with unfavorable outcome after abdominal aortic aneurysm (AAA) endografting. METHODS: In a prospective pivotal clinical trial, 237 consecutive patients underwent implantation of the bifurcated Talent Low Profile System. Patients were divided into 2 groups, those with complicated aortic necks (short, <15 mm; very short, < or =10 mm; dilated, >28 mm; angulated, >45 degrees; calcified; and thrombus-lined) versus those with uncomplicated neck anatomy. Major outcome parameters included procedure time, operative blood loss, transfusion requirements, volume of contrast medium used during the implant procedure, endoleaks, migration, limb patency, AAA regression, conversion to open repair, morbidity, and mortality. Mean follow-up was 620.5 days. RESULTS: Overall, 32% of aortic necks were short, 19% were very short, 20% were dilated, 18% were calcified, 8.5% were thrombus-lined, and 19.9% were angulated. Thirty percent and 70% of patients, respectively, were stratified to the uncomplicated and complicated groups ( P < .01. Procedure time, operative blood loss, transfusions, volume of contrast medium used in the implant procedure, migration, endograft patency, AAA sac regression, conversion to open repair, and mortality were not significantly different in necks with complicated versus uncomplicated anatomy. At 21 months, sacs were regressing or stable in 98% (complicated) versus 96% (uncomplicated). Primary graft limb patency was 100% in both groups. The endoleak rate was 4.3% (complicated) versus 17% (uncomplicated) at 18 months, but this difference was not statistically significant. Adverse renal events, however, occurred in 27.5% (complicated) versus 13.6% (uncomplicated; P = .04). CONCLUSIONS: Complicated aortic neck is not associated with unfavorable outcome at midterm follow-up after AAA endografting. However, statistically more adverse renal events occur in patients with complicated neck anatomy. 相似文献
996.
Originally developed in the context of publicly traded for-profit companies, theory of constraints (TOC) improves system performance through leveraging the constraint(s). While the theory seems to be a natural fit for resource-constrained publicly funded health systems, there is a lack of literature addressing the modifications required to adopt TOC and define the goal and performance measures. This paper develops a system dynamics representation of the classical TOC’s system-wide goal and performance measures for publicly traded for-profit companies, which forms the basis for developing a similar model for publicly funded health systems. The model is then expanded to include some of the factors that affect system performance, providing a framework to apply TOC’s process of ongoing improvement in publicly funded health systems. Future research is required to more accurately define the factors affecting system performance and populate the model with evidence-based estimates for various parameters in order to use the model to guide TOC’s process of ongoing improvement. 相似文献
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