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排序方式: 共有894条查询结果,搜索用时 62 毫秒
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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
3.
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
4.
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
5.
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
6.
It has been suggested that there is a widespread abnormality of the capillaries in the skin of patients with psoriasis. This study was carried out to obtain more evidence on this point. Lesions of 20 patients with typical psoriasis, and uninvolved skin 3 cm from these lesions, were biopsied and compared with biopsies from 10 normal healthy control subjects. The dermal microvasculature was quantified in all these biopsies with regard to endothelial and luminal volume relative to the volume of dermal components of skin using stereological point counting methods utilizing the Delesse principle. The values for endothelial volume in specimens taken from the centre of the lesions did not differ significantly from those taken from the margins (33.6 x 10(-3) and 35.8 x 10(-3), respectively). The same was true for the luminal volume from the two sites (9.1 x 10(-3) and 10.0 x 10(-3), respectively). There was a highly significant difference, however, between the value for endothelial volume in biopsies from psoriatic patients compared to controls (P less than 0.001) and specimens from uninvolved psoriatic skin also showed a highly significant difference (P less than 0.001) from involved areas. There was no significant difference between uninvolved areas in psoriasis patients and control specimens. Significant differences were also found between values for control subjects and those for both involved and uninvolved psoriatic skin for luminal volume (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Unilateral bullous pemphigoid in a hemiplegic pagtient 总被引:1,自引:0,他引:1
A 78-year-old man with a long-standing left-sided hemiplegia presented with bullous pemphigoid which affected his paralysed side only. Although the rash was unilateral, direct immunofluorescence demonstrated IgG antibody at the dermo-epidermal junction on both sides of the body. Indirect immunofluorescence was also positive. A suction-blister test showed increased skin fragility on the affected side. 相似文献
8.
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
9.
Identification of genes associated with ovarian cancer metastasis using microarray expression analysis 总被引:1,自引:0,他引:1
J.M. LANCASTER H.K. DRESSMAN†‡ J.P. CLARKE§ R.A. SAYER M.A. MARTINO J.M. CRAGUN A.H. HENRIOTT J. GRAY¶ R. SUTPHEN A. ELAHI R.S. WHITAKER M. WEST# J.R. MARKS J.R. NEVINS†‡ & A. BERCHUCK 《International journal of gynecological cancer》2006,16(5):1733-1745
Although the transition from early- to advanced-stage ovarian cancer is a critical determinant of survival, little is known about the molecular underpinnings of ovarian metastasis. We hypothesize that microarray analysis of global gene expression patterns in primary ovarian cancer and metastatic omental implants can identify genes that underlie the metastatic process in epithelial ovarian cancer. We utilized Affymetrix U95Av2 microarrays to characterize the molecular alterations that underlie omental metastasis from 47 epithelial ovarian cancer samples collected from multiple sites in 20 patients undergoing primary surgical cytoreduction for advanced-stage (IIIC/IV) serous ovarian cancer. Fifty-six genes demonstrated differential expression between ovarian and omental samples (P < 0.01), and twenty of these 56 differentially expressed genes have previously been implicated in metastasis, cell motility, or cytoskeletal function. Ten of the 56 genes are involved in p53 gene pathways. A Bayesian statistical tree analysis was used to identify a 27-gene expression pattern that could accurately predict the site of tumor (ovary versus omentum). This predictive model was evaluated using an external data set. Nine of the 27 predictive genes have previously been shown to be involved in oncogenesis and/or metastasis, and 10/27 genes have been implicated in p53 pathways. Microarray findings were validated by real-time quantitative PCR. We conclude that gene expression patterns that distinguish omental metastasis from primary epithelial ovarian cancer can be identified and that many of the genes have functions that are biologically consistent with a role in oncogenesis, metastasis, and p53 gene networks. 相似文献
10.