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261.
Validation and calibration of physical activity monitors in children 总被引:11,自引:0,他引:11
OBJECTIVE: This study was designed to validate accelerometer-based activity monitors against energy expenditure (EE) in children; to compare monitor placement sites; to field-test the monitors; and to establish sedentary, light, moderate, and vigorous threshold counts. RESEARCH METHODS AND PROCEDURES: Computer Science and Applications Actigraph (CSA) and Mini-Mitter Actiwatch (MM) monitors, on the hip or lower leg, were validated and calibrated against 6-hour EE measurements by room respiration calorimetry, activity by microwave detector, and heart rate by telemetry in 26 children, 6 to 16 years old. During the 6 hours, the children performed structured activities, including resting metabolic rate (RMR), Nintendo, arts and crafts, aerobic warm-up, Tae Bo, treadmill walking and running, and games. Activity energy expenditure (AEE) computed as EE - RMR was regressed against counts to derive threshold counts. RESULTS: The mean correlations between EE or AEE and counts were slightly higher for MM-hip (r = 0.78 +/- 0.06) and MM-leg (r = 0.80 +/- 0.05) than CSA-hip (r = 0.66 +/- 0.08) and CSA-leg (r = 0.73 +/- 0.07). CSA and MM performed similarly on the hip (inter-instrument r = 0.88) and on the lower leg (inter-instrument r = 0.89). Threshold counts for the CSA-hip were <800, <3200, <8200, and > or = 8200 for sedentary, light, moderate, and vigorous categories, respectively. For the MM-hip, the threshold counts were <100, <900, <2200, and > or = 2200, respectively. DISCUSSION: The validation of the CSA and MM monitors against AEE and their calibration for sedentary, light, moderate, and vigorous thresholds certify these monitors as valid, useful devices for the assessment of physical activity in children. 相似文献
262.
Anticoagulant activity of heparin following oral administration of heparin-loaded microparticles in rabbits 总被引:4,自引:0,他引:4
Jiao Y Ubrich N Hoffart V Marchand-Arvier M Vigneron C Hoffman M Maincent P 《Journal of pharmaceutical sciences》2002,91(3):760-768
Heparin-loaded microparticles, prepared according to the double emulsion method with biodegradable (PCL and PLGA) and nonbiodegradable (Eudragit RS and RL) polymers used alone or in combination, with or without gelatin, were characterized in vitro and in vivo after oral administration in rabbits. The entrapment efficiency and the release of heparin were determined by a colorimetric method with Azure II. The antifactor Xa activity of heparin released in vitro after 24 h was assessed. After oral administration of heparin-loaded microparticles in rabbits, the time course of modification of the clotting time estimated by the activated partial thromboplastin time (APTT) was followed over 24 h. Microparticles with a size ranging from 80 to 280 microm were obtained. Heparin entrapment efficiency as well as heparin release depended on both the nature of the polymers and the presence of gelatin. The Eudragit polymers increased the drug loading but slowed down the heparin release, whereas gelatin accelerated the release. No change in clotting time was observed after oral administration of gelatin microparticles. Heparin-loaded microparticles prepared with blends of PLGA and Eudragit displayed a prolonged duration of action characterized by a twofold increase in APTT and a enhancement of absorption. This study demonstrated the feasibility of encapsulating heparin within polymeric particles, and the significant increase in APTT confirmed the oral absorption of heparin released from polymeric microparticles. 相似文献
263.
264.
Four new flavonol 3-O-glycosides were isolated from the leaves of Astragalus caprinus. Their structures were elucidated by spectroscopic methods as rhamnocitrin-3-O-[3-hydroxy-3-methylglutaroyl(1-->6)][beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (1), rhamnetin-3-O-[3-hydroxy-3-methylglutaroyl(1-->6)][beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (2), kaempferol-3-O-[beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)]-beta-D-galactopyranoside (3), and quercetin-3-O-[beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)][beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (4). 相似文献
265.
Cardiac metastases from renal cell carcinoma are a well-recognized entity. However, this phenomenon is extremely rare in the absence of vena caval extension. The authors report a patient who after successful resection of renal cell carcinoma presented with left ventricular mass causing left ventricular outflow tract obstruction. There was also metastatic pericardial and intramyocardial involvement. Such a unique combination of cardiac metastasis, in the same patient, has not been reported previously. 相似文献
266.
In patients with valvular regurgitation, the regurgitation jet can be observed by Doppler color flow imaging. Vena contracta
is defined as the narrowest part of the jet, just distal to the regurgitant orifice. Vena contracta dimensions reflect the
severity of regurgitation. Vena contracta diameter, usually easy to measure in clinical practice, is well correlated with
the effective regurgitant orifice area and the regurgitant volume. Cutoff values have been determined to identify severe regurgitation
for mitral, aortic, and tricuspid valves. In clinical practice, determination of vena contracta diameter is a useful and simple
method for assessment of valvular regurgitation. In the future, assessment of complex jet regurgitations will probably benefit
from the contribution of three-dimensional Doppler flow imaging, which should improve the performances of the method. 相似文献
267.
Tarnow D Elian N Fletcher P Froum S Magner A Cho SC Salama M Salama H Garber DA 《Journal of periodontology》2003,74(12):1785-1788
BACKGROUND: As patient demand increases for more natural restorations in the esthetic zone, clinicians must have the highest level of skill and knowledge to maintain or reform the interdental papilla between teeth, between implants and teeth, and between adjacent implants. To date, there are no reports that have measured the distance from the contact point to the bony crest between implants. One reason for this may be the fact that, with two adjacent implants, the contact point of the crown can be established at any distance from the gingival margin according to the restorative dentist's specifications. Therefore, in this study, the height of the soft tissue to the crest of bone was measured between two adjacent implants independent of the location of the contact point. The purpose of this study was to determine the range and average height of tissue between two adjacent implants. METHODS: A total of 136 interimplant papillary heights were examined in 33 patients by eight different examiners in five private dental offices. After administration of appropriate local anesthesia, a standardized periodontal probe was placed vertically from the height of the papilla to the crest of bone. The measurements were rounded off to the nearest millimeter. RESULTS: The mean height of papillary tissue between two adjacent implants was 3.4 mm, with a range of 1 mm to 7 mm. CONCLUSIONS: Clinicians should proceed with great caution when placing two implants adjacent to each other in the esthetic zone. In most cases, only 2, 3, or 4 mm of soft tissue height (average 3.4 mm) can be expected to form over the interimplant crest of bone. These results showed that modification of treatment plans may be necessary when esthetics are critical for success. 相似文献
268.
The effects of breathing-related sleep disorders on mood disturbances in the general population 总被引:4,自引:0,他引:4
Ohayon MM 《The Journal of clinical psychiatry》2003,64(10):1195-200; quiz, 1274-6
BACKGROUND: Results of clinical studies suggest that there may be a relationship between breathing-related sleep disorders and depressive disorders. This study aims to assess the impact of breathing-related sleep disorder on major depressive disorder in the general population. METHOD: A cross-sectional telephone survey was carried out between 1994 and 1999 in the general population of the United Kingdom, Germany, Italy, Portugal, and Spain. A total of 18,980 randomly selected subjects aged 15 to 100 years and representative of the general population of their respective countries participated in the study. The questionnaire included a series of questions about sleep quality, breathing-related sleep disorder symptoms, mental disorders, and medical conditions. Data are presented using point prevalence. RESULTS: 2.1% of the subjects were found with obstructive sleep apnea syndrome at the time of the interview, and 2.5% had some other type of DSM-IV breathing-related sleep disorder diagnosis. The association of DSM-IV breathing-related sleep disorder diagnosis and major depressive disorder diagnosis was found in 0.8% of the sample. As many as 18% of individuals with a major depressive disorder diagnosis also have a DSM-IV breathing-related sleep disorders diagnosis, and 17.6% of subjects with a DSM-IV breathing-related sleep disorders diagnosis have a major depressive disorder diagnosis. Multivariate models showed that even after controlling for obesity and hypertension, the odds of having a DSM-IV breathing-related sleep disorders diagnosis was 5.26 for individuals with a major depressive disorder diagnosis. CONCLUSION: About 800 of 100,000 individuals have both a breathing-related sleep disorder and a major depressive disorder. The identification of 1 of these 2 disorders should prompt the investigation of the other disorder since nearly a fifth of them have the other disorder. 相似文献
269.
Behavioral data management using Visual Basics for Applications to automate data capture and analysis 总被引:2,自引:0,他引:2
Many researchers are familiar with the spreadsheet capabilities of Microsoft Excel, but have never explored using customized VISUAL BASIC FOR APPLICATIONS (VBA) macros embedded in the program. At the United States Army Medical Research Institute of Chemical Defense (USAMRICD), the implementation of VBA program code to carry out repetitive operations has resulted in a tremendous savings in both the time and manpower required to reliably capture, analyze, and plot data from research protocols. A set of "template" workbooks was developed and is used to organize data from different types of studies. At the heart of the concept is a "setup information" worksheet onto which the user enters information about the study (i.e. the number of subjects, groups, graphs). Clicking a control button on this worksheet launches the VBA code that creates worksheets for each subject, group and chart specified. A "pairmatch" function allows the user to create groups either randomly or by pair matching based on user-specified variables. Controls are provided that run VBA program code to parse subject data files into the proper worksheets and perform group averages. Charts are updated automatically whenever group averages change so that the researcher always has an up-to-date plot available. The ability to reformat the captured data onto a "statistical output" worksheet allows data to be imported easily to statistical software packages. The concept is being used for several different types of studies at USAMRICD and has significantly reduced not only amount of time spent on data management, but also the number of data entry errors. Readers interested in acquiring an electronic copy of the startle workbook example, which contains the complete VBA code, should send the request to the authors at reseco@erols.com or maurice.sipos@us.army.mil. 相似文献
270.
Senard M Joris JL Ledoux D Toussaint PJ Lahaye-Goffart B Lamy ML 《Anesthesia and analgesia》2002,95(2):444-9, table of contents
Ropivacaine (ROPI), which is less toxic and produces less motor block than bupivacaine (BUPI), seems attractive for epidural analgesia. Few data are available concerning dose requirements of epidural ROPI when combined with morphine. In this study, we compared the dose requirements and side effects of ROPI and BUPI combined with small-dose morphine after major abdominal surgery. Postoperatively, 60 patients were randomly allocated (double-blinded manner) to four groups: patient-controlled epidural analgesia with the same settings using 0.1% or 0.2% solution of ROPI or BUPI combined with an epidural infusion of 0.1 mg/h of morphine. Pain scores, side effects, motor block, and local anesthetic consumption were measured for 60 h. Pain scores and the incidence of side effects did not differ among the groups. Consumption of ROPI and BUPI were similar in both 0.1% groups. Doubling the concentration significantly reduced the consumption (milliliters) of BUPI (P < 0.05) but not of ROPI. Consequently, using ROPI 0.2% significantly increased the dose administered as compared with ROPI 0.1% (ROPI 0.1% = 314 +/- 151 mg and ROPI 0.2% = 573 +/- 304 mg at Hour 48; P < 0.05). Patient-controlled epidural analgesia with the 0.1% or 0.2% solution of ROPI or BUPI combined with epidural morphine resulted in comparable analgesia. As compared with ROPI 0.1%, the use of ROPI 0.2% increased consumption of local anesthetic without improving analgesia. IMPLICATIONS: Small-dose (0.1%) ropivacaine and bupivacaine have similar potency and result in comparable analgesia and incidence of side effects. 相似文献