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1.
LARRY A. TUCKER PhD GARY T. SELJAAS MS RONALD L. HAGER MS 《Journal of the American Dietetic Association》1997,97(9):981-986
Objective To ascertain the association between diet composition and body fat percentage in 9- and 10-year-old children. Also, to examine the influence of gender, total energy intake, fitness, physical activity, and parental body mass on the relationship between diet composition and adiposity.Design Diet composition was assessed using the National Cancer Institute food frequency questionnaire, and adiposity was measured using the average of results determined using two skinfold equations. Fitness levels and physical activity were ascertained using the 1-mile run/walk test and a self-report 15-item scale, respectively.Subjects A sample of 262 children (162 boys and 100 girls, mean age=9.8±0.5 years) participated.Statistical analysis Regression analysis was used to determine the extent to which diet composition contributed to adiposity without statistical control for any potentially confounding variables. Partial correlations were calculated to assess the relationship between macronutrient intake and adiposity after potential confounders (gender, total energy intake, physical fitness, and parental body mass) were controlled statistically.Results Energy intake was positively related to adiposity. Fat intake, calculated as a percentage of total energy, was also positively related to adiposity, before and after control for potential confounding variables. Percentage of energy derived from carbohydrate was inversely related to adiposity, before and after controlling for potential confounders.Applications These findings indicate that the macronutrient intake of children, particularly dietary fat and carbohydrate intake, may play a role in adiposity, independent of the influence of total energy intake, gender, physical fitness, and parental body mass index. 相似文献
2.
JOHN P. BOURKE LYNNE HOWELL ALAN MURRAY WILLIAM E. HILL J. CAMPBELL COWAN KEVIN BEATT JOAN ERRINCTON STUART JAMESON RONALD G. GOLD 《Pacing and clinical electrophysiology : PACE》1989,12(8):1419-1425
A randomized prospective study was undertaken to compare the electrical performances of three permanent, endocardial, tined pacing leads with different electrode designs--sintered platinum, vitreous carbon, and porous carbon. Ninety-nine patients received one of the leads (S80 31; 423S 32; S100 36). Acute R wave amplitude and ST elevation of the native endocardial electrogram, voltage threshold, impedance, and current flow at four pulse durations (0.25-1.0 msec) were measured. Voltage thresholds were measured noninvasively at each of four pulse durations at 2 days and 1, 3, and 6 months after implantation. No significant differences were found in sensing properties, or current flow at threshold at 0.5 msec pulse duration. The 423S lead had a significantly higher impedance at threshold and both a higher impedance and lower current flow at 5 V. No significant differences in threshold voltages were found between the three leads at any pulse duration, at any of the assessed times after implantation. Six-month thresholds for the S80, 423S, and S100 leads were 1.18 +/- 0.35, 1.17 +/- 0.29, and 1.06 +/- 0.38 V respectively at 0.5 msec pulse duration. Differences between 'high performance' pacing leads need to be of a greater order of magnitude before they can be exploited to give any real clinical advantage to patients. 相似文献
3.
STEVEN N. VASLEF LYLE F. MOCKROS KEITH E. COOK RONALD J. LEONARD JEFFREY C. SUNG ROBERT W. ANDERSON 《Artificial organs》1994,18(11):813-817
Abstract: A semiempirical mathematical model of convective oxygen transport is used to design a new, low pressure loss, implantable artificial lung that could be used as a bridge to lung transplantation in patients with advanced respiratory failure. The mass transfer and flow friction relations pertinent to the design of a cross–flow hollow fiber membrane lung are described. The artificial lung is designed to transfer over 200 ml/min of oxygen at blood flow rates up to 5 L/min. A compact design and a blood-side pressure loss of <15 mm Hg allows the device to be implanted in the left chest without the need for a prosthetic blood pump. Surgical implantation of the artificial lung would require the creation of inflow and outflow anastomoses. Oxygen would be supplied via an external source. Blood properties, operating conditions, and empirically determined mass transfer and flow properties are all specified and input into a computer program that numerically solves the design equations. Computer–generated values for the device frontal area, blood path length, and fiber surface area are thereby obtained. The use of this computer–assisted design minimizes the need for extensive trial–and–error testing of prototype devices. Results from in vitro tests of a prototype implantable lung indicate that the mathematical model we describe is an accurate and useful tool in the design of hollow fiber artificial lungs. 相似文献
4.
KANKIPATI SHANTI RAJU Lecturer/Senior Registrar RONALD W. TAYLOR Professor of Obstetrics Gynaecology 《BJOG : an international journal of obstetrics and gynaecology》1986,93(12):1259-1261
Summary. Seventy patients with abnormal vaginal bleeding were examined with a Storz hysteroscope. The examination took an average of only 5 min. Sixty patients had the examination under general anaesthesia, five under paracervical block and five had no form of anaesthesia. All tolerated the procedure well. There were no complications directly related to the hysteroscopic examination. There was complete correlation between the histology of the endometrium obtained at subsequent curettage and the hysteroscopic findings. 相似文献
5.
It is well known that prevalence and incidence rates of cardiovasculardisease (CVD) and CVD risk factors are not equally distributedamong socioeconomic groups. Known risk factors account for part,but not all of unequally distributed CVD rates. Socioeconomicconditions and psychosocial dynamics may explain another pareof the increased CVD rates. Theoretically, it may be possibleto lower CVD rates and CVD risk factor prevalence among lowersocioeconomic status (SES) groups by using a community development(socio-environment) strategy directed towards changes in socioenvrronmentalrisk conditions and psychosocial risk factors, rather than CVDrisk factors per Se. This article describes a protocol for sucha strategy based upon the planning work of Canadian health professionals,loosely organized under a project titled Heart HealthInequalities in Canada This protocol incorporates baselinedata on CVD and CVD risk factor prevalence, but is premisedon actions negotiated between community organizations and healthauthorities, rather than defined unilaterally by health authorities.As such, program design activities and evaluation will differfrom a more general population-based risk factor reduction strategy. 相似文献
6.
BRUCE J. ROUNSAVILLE KENDALL BRYANT THOMAS BABOR HENRY KRANZLER RONALD KADDEN 《Addiction (Abingdon, England)》1993,88(3):337-348
This report presents results of a field trial of Substance Use Disorders as defined by DSM-III-R, DSM-IV (proposed) and ICD-10. Diagnoses based on the three systems were derived from interviews using the Composite International Diagnostic Interview (CIDI) in a heterogeneous sample of 521 adults drawn from clinical and community settings. Two issues are addressed: (1) cross system agreement; and (2) syndrome coherence of proposed criterion sets for Substance Dependence in each of the three systems. Findings were as follows: (1) Cross system agreement for Dependence was generally high, especially between DSM-III-R and DSM-IV. (2) Cross system agreement was lower for DSM-III-R and DSM-IV Abuse and very low for DSM-IV Abuse and ICD-10 Harmful Use. (3) Agreement varied across drug categories with lowest DSM-III-R/DSM-IV agreement for alcohol abuse and DSM-IV/ICD-10 agreement for marijuana use disorders. (4) Overall prevalence differed for the three systems with DSM-IV yielding highest rates followed by DSM-III-R and ICD-10 in that order. (5) Factor analysis of Dependence criteria showed high loadings of all items on a single factor across the three diagnostic systems and for all categories of drugs. Implications for validity of the dependence syndrome construct and for revisions in DSM-IV are discussed. 相似文献
7.
In Vivo and in Vitro Percutaneous Absorption and Skin Decontamination of Arsenic from Water and Soil 总被引:1,自引:1,他引:0
WESTER RONALD C.; MAIBACH HOWARD I.; SEDIK LENA; MELENDRES JOSEPH; WADE MICHAEL 《Toxicological sciences》1993,20(3):336-340
The objective was to determine the percutaneous absorption ofarsenic-73 as H3AsO4 from water and soil. Soil (Yolo County65-California-57-8) was passed through 10-, 20-, and 48-meshsieves. Soil retained by 80 mesh was mixed with radioactivearsenic-73 at a low (trace) level of 0.0004 µg/cm2 (microgramsarsenic per square centimeter skin surface area) and a higherdose of 0.6 µg/cm2. Water solutions of arsenic-73 at alow (trace) level of 0.000024 µg/cm2 and a higher doseof 2.1 µg/cm2 were prepared for comparative analysis.In vivo in Rhesus monkey a total of 80.1 ± 6.7% (SD)intravenous arsenic-73 dose was recovered in urine over 7 days;the majority of the dose was excreted in the first day. Withtopical administration for 24 hr, absorption of the low dosefrom water was 6.4 ± 3.9% and 2.0 ± 1.2% fromthe high dose. In vitro percutaneous absorption of the low dosefrom water with human skin resulted in 24-hr receptor fluid(phosphate-buffered saline) accumulation of 0.93 ± 1.1%dose and skin concentration (after washing) of 0.98 ±0.96%. Combining receptor fluid accumulation and skin concentrationgave a combined amount of 1.9%, a value less than that in vivo(6.4%) in the Rhesus monkey. From soil, receptor fluid accumulationwas 0.43 ± 0.54% and skin concentration was 0.33 ±0.25%. Combining receptor fluid plus skin concentrations gavean absorption value of 0.8%, an amount less than that with invivo absorption (4.5%) in the Rhesus. These absorption valuesdid not match current EPA default assumptions. Washing withsoap and water readily removed residual skin surface arsenic,both in vitro and in vivo. The partition coefficient of arsenicin water to powdered human stratum corneum was 1.1 x 104andfrom water to soil it was 2.5 x 104. This relative similarityin arsenic binding to powdered human stratum corneum and soilmay indicate why arsenic absorption was similar from water andsoil. This powdered human stratum corneum partition coefficientmodel may provide a facile method for such predictions. 相似文献
8.
THOMAS PETER; RATAJCZAK HELEN; DEMETRAL DENISE; HAGEN KAREN; BARON RONALD 《Toxicological sciences》1990,15(2):221-230
Aldicarb Immunotoxicity: Functional Analysis of Cell-MediatedImmunity and Quantitation of Lymphocyte Subpopulations. THOMAS,P., RATAJCZAK, H., DEMETRAL, D., HAGEN, K., AND BARON, R. (1990).Fundam. Appl. Toxicol. 15, 221230. Adult female B6C3F1mice received distilled water only or water containing 1.0,10, or 100 ppb of aldicarb daily for 34 days. The target concentrationof aldicarb present in the 100 ppb dosing solution was analyticallyverified. To further develop an immune profile of this compound,following aldicarb exposure, the ability of splenic naturalkiller cells and specifically sensitized cytotoxic T-lymphocytesto lyse YAC-1 lymphoma and P815 tumor cells, respectively, wasevaluated. To supplement the functional assays, the impact ofaldicarb exposure on the percentages and absolute numbers oftotal T-cells, T-suppressor, T-helper, and B-cells was evaluated.The absence of statistically significant effects on any of theseparameters supports earlier reports that aldicarb does not resultin adverse effects on the immune system of mice. 相似文献
9.
10.
Chronic Dietary Toxicity/Oncogenicity Studies on 2,4-Dichlorophenoxyacetic Acid in Rodents 总被引:1,自引:1,他引:0
CHARLES JEFFREY M.; BOND DENISE M.; JEFFRIES TONI K.; YANO BARRY L.; STOTT WILLIAM T.; JOHNSON KEITH A.; CUNNY HELEN C.; WILSON RONALD D.; BUS JAMES S. 《Toxicological sciences》1996,33(2):166-172
Forms of 2,4-dichlorophenoxyacetic acid (collectively knownas 2,4-D) are herbicides used to control a wide variety of broadleafand woody plants. Doses in the 2-year chronic/oncogenicity ratstudy were 0, 5, 75, and 150 mg/kg/day. The chronic toxicityparalleled subchronic findings, and a NOEL of 5 mg/kg/day wasestablished. A slight increase in astrocytomas observed (inmales only) at 45 mg/kg/day in a previously conducted chronicrat study was not confirmed in the present study at the highdose of 150 mg/kg/day. Doses in the 2-year mouse oncogenicitystudies were 0, 5, 150, and 300 mg/kg/day for females and 0,5, 62.5, and 125 mg/kg/day for males. No oncogenic effect wasnoted in the study. In summary, the findings of these studiesindicate low chronic toxicity of 2,4-D and the lack of oncogenicresponse to 2,4-D following chronic dietary exposure of 2,4-Din the rat and mouse. 相似文献