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941.
The early institution of enteral nutrition is now accepted as the preferred route of feeding in critically ill patients with a functioning gastrointestinal tract. It is particularly important to establish early enteral nutrition in mechanically ventilated patients because of the metabolic demands associated with mechanical ventilation. The options for enteral access in mechanically ventilated patients are reviewed, with an emphasis on those techniques that may be performed at the bedside. The advantages, disadvantages, and complications of the different techniques will be considered. 相似文献
942.
943.
Jean-Yves Driot Gary D Novack Kay D Rittenhouse Chris Milazzo P Andrew Pearson 《Journal of ocular pharmacology and therapeutics》2004,20(3):269-275
PURPOSE: The present study was designed to examine the pharmacokinetics of a fluocinolone acetonide (FA) intravitreal implant in pigmented rabbits. METHODS: Pigmented rabbits were randomly assigned to receive either a 0.5 mg or 2.0 mg FA intravitreal implant (Retisert). Four animals were sacrificed per time point (2 hours; 2 weeks; and 3, 6, 9, and 12 months after implantation) for FA intraocular levels determination. RESULTS: In the vitreous, concentration of FA was relatively constant from the first time point, 2 hours, through 1 year, and dose-related, approximately seven- to eight-fold greater in the 2-mg implant. Concentrations of FA were generally higher in the vitreous (11-18 and 75-146 ng/g) and retina (42-87 and 224-489 ng/g) than in the aqueous humor (0.21-1.1 and 2.6-13.0 ng/g) for the 0.5- and 2-mg implants, respectively. Urine and plasma values were below the lower limit of quantitation (200 pg/mL) for all observations, indicating no evidence of systemic absorption. CONCLUSIONS: In this rabbit study, the Retisert provides relatively constant levels of FA in the posterior pole, which is consistent with previous reports of its clinical utility. 相似文献
944.
Repeatability of IOLMaster biometry in children. 总被引:3,自引:0,他引:3
Andrew Carkeet Seang-Mei Saw Gus Gazzard Wilfred Tang Donald T H Tan 《Optometry and vision science》2004,81(11):829-834
AIMS: This study compares the repeatability of IOLMaster (Zeiss, Oberkochen, Germany) axial dimension measurements and conventional ultrasonography in children. METHODS: A series of IOLMaster (partial coherence interferometry, optical pachometry) and Echoscan (US 800, Nidek, Tokyo, Japan) (ultrasound) measurements were taken on 179 Chinese children (mean age, 10.6 +/- 0.8 years) taking part in a longitudinal study of myopia development, and the measurements were repeated on 37 of these subjects. RESULTS: IOLMaster axial length measurements showed better repeatability (95% limits of agreement for repeatability, -0.047 to 0.038 mm) than Echoscan axial length measurements (95% limits of agreement for repeatability, -0.85 to 0.67 mm). IOLMaster anterior chamber depth measurements also showed better repeatability (95% limits of agreement for repeatability, -0.053 to 0.073 mm) than Echoscan anterior chamber depth measurements (95% limits of agreement for repeatability, -0.57 to 0.49 mm). IOLMaster measurements were, on average, slightly larger than Echoscan measurements for axial length (by 0.14 mm) and anterior chamber depth (0.09 mm). CONCLUSION: Partial coherence interferometry techniques, such as that used by IOLMaster, should be considered as the standard technique for axial length measurement in children because they are noninvasive, highly precise, and easy to use. 相似文献
945.
946.
John Kirkland David Bimler Andrew Drawneek Margaret McKim Axel Sch lmerich 《Early child development and care》2004,174(7):701-719
Attachment Q-Sort (AQS) is a tool for quantifying observations about toddler/caregiver relationships. Previous studies have applied factor analysis to the full 90 AQS item set to explore the structure underlying them. Here we explore that structure by applying multidimensional scaling (MDS) to judgements of inter-item similarity. AQS items are arranged in the MDS solution along three easily interpretable axes: a model that is compatible with but more parsimonious than factor analysis solutions. This geometrical approach suggests ways to modify the AQS—primarily a research tool—to make it more practical for clinical applications. Sets of AQS data are represented and interpreted in the three-dimensional model as vectors. Summaries at a finer-grained level are obtained by finding points in the model where variability across datasets is greatest. We report re-analyses of archival (published) data, and also data collected with streamlined procedures more suitable in the field. Although not reported here, collection and analysis can both be performed online via a website. The general methodology is not restricted to the current application of toddler attachment. 相似文献
947.
948.
Randal D Beaten Andrew Stevermer Julie Wicklund David Owens Janice Boase Mark W Oberle 《JPHMP》2004,10(1):77-85
On January 24, 2002, the Washington State Department of Health, in collaboration with local and federal agencies, conducted an exercise of the Centers for Disease Control and Prevention's National Pharmaceutical Stockpile dispensing portion of the Washington State plan. This exercise included predrill planning, training, and the orchestration of services of more than 40 dispensary site workers. These workers provided education and post-exposure prophylaxis for over 230 patient volunteers in the aftermath of a simulated exposure to B. anthracis. This article discusses findings of a postdrill questionnaire completed by 90% of these dispensary site workers who provided triage, education, dispensary, security and other services during this exercise. In general, this dispensing drill promoted confidence in the worker participants and provided an opportunity for these participants to coordinate their activities. This mock bioterrorist preparedness exercise allowed worker participants and observers to review and evaluate the Washington State plan for dispensing the National Pharmaceutical Stockpile. This article is apparently the first published account of dispensary site workers' subjective impressions and quantitative analysis of their postdrill opinions following a simulated bioterrorist post-exposure chemoprophylaxis dispensing exercise. 相似文献
949.
目的对8例HIV长期感染不进展(LTNP)及病程进展缓慢(SP)患者的病毒特异性细胞毒性T细胞(CTL)特征进行研究。方法设立队列研究,从中随机选出8例患者(4例LTNPs,4例SP)。通过采用重叠肽技术组建HIV-1B亚型全序列肽段,组建成三维肽库进行ELISPOT分析8例患者的HIV-1特异性细胞免疫反应。结果在大多数患者中存在较强的T细胞反应,特别对HIV-1病毒的pol、gag、nef蛋白的免疫反应比其他蛋白强。结论病毒特异性CTL免疫反应在HIV-1 LTNPs有较强并且很广泛的反应,这对于有效抑制病毒在人体内的生存有可能起到很大的作用,很可能是这些LTNPs及SP病程进展缓慢的主要原因之一。 相似文献
950.
Michael von Brevern Tanja Schmidt Uwe Sch?nfeld Thomas Lempert Andrew H Clarke 《Otology & neurotology》2006,27(1):92-96
OBJECTIVE: The objective of this study was to test the hypothesis that utricular function is impaired in patients with idiopathic benign paroxysmal positional vertigo. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary dizziness clinic and vestibular research laboratory. PATIENTS: Twelve patients with unilateral idiopathic benign paroxysmal positional vertigo were examined 1 week and 1 month after successful treatment with positioning maneuvers and compared with 24 healthy subjects. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Otolith function was assessed with estimation of the subjective visual vertical and analysis of the torsional otolith-ocular reflex. Unilateral stimulation of the utricle was performed on a rotator that allowed eccentric lateral displacement of the patient during earth-vertical rotation with constant velocity. The otolith-ocular reflex was recorded with three-dimensional video-oculography. RESULTS: There was no difference in the estimation of the subjective visual vertical between patients and controls. The peak-to-peak amplitude of the otolith-ocular reflex torsional eye position was smaller in patients than in the control group. The gain of the unilateral otolith-ocular reflex was reduced in patients on both sides on first testing. After several weeks, only the affected labyrinth showed a reduced otolith-ocular reflex gain. CONCLUSION: Our findings document otolith dysfunction in patients with idiopathic benign paroxysmal positional vertigo possibly secondary to degeneration of the utricular macula. This finding may account for the transient mild imbalance and dizziness that some patients with benign paroxysmal positional vertigo experience even after resolution of positional vertigo. 相似文献