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71.
72.
Marlene S. See M. R. Foxton N. A. Miedzianowski-Sinclair C. E. Roberts C. Nduka 《European journal of plastic surgery》2007,29(8):387-393
The nasolabial fold is a significant facial landmark. Its size, shape, and symmetry are important in facial reanimation surgery,
while effacement is an important goal in rejuvenation surgery. However, quantitative data for the nasolabial fold volume (NLFV)
and depth is still unavailable. We present a new method of measurement using 3D color speckle stereophotogrammetry and its
application in the assessment of NLFV. The VECTRA-3D system was validated to determine its minimum resolution and accuracy.
Normal volunteers aged 13–84 years (n = 87) were imaged in repose. Mother–daughter pairs (n = 15, aged 13–61) were imaged in the upright and supine positions. All data were processed using custom software and analyzed
by linear regression and nonparametric tests as appropriate. NLFV varied from 0.0026 to 0.2306 ml. There was significant correlation
between NLFV and age (r = 0.7269, p < 0.0001). Men had significantly higher NLFV than women across all ages. There was no significant difference between the
left and right NLFV. NLFV altered significantly from upright to supine in all subjects (p = 0.0012). However, the mothers increased their NLFV by 32% from supine to upright postures, which was a greater change than
observed in their daughters. We have demonstrated a rapid, objective, and non-invasive assessment tool for facial reanimation
and rejuvenation surgery. We have quantified the effects of age and posture on NLFV, and the efficacy and longevity of rejuvenation
procedures are currently under investigation. 相似文献
73.
74.
Jessica Swoboda DDS H. Asuman Kiyak MA PhD Rigmor E. Persson DDS MSD G. Rutger Persson DDS PhD David K. Yamaguchi PhD Michael I. MacEntee LDS FRCD© PhD Christopher C.L. Wyatt BSc DMD MSc 《Special care in dentistry》2006,26(4):137-144
There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role. 相似文献
75.
76.
JANET E. PRITCHARD MSc APD MDAA CARYL A. NOWSON PhD MDAA JOHN D. WARK MBBS PhD FRACP 《Journal of the American Dietetic Association》1997,97(1):37-42
Objective To compare changes in total and regional body composition using dual energy X-ray absorptiometry (DEXA) after subjects lost weight through change in diet or exercise.Design A 12-month, randomized, controlled study of two weight-loss interventions — low-fat diet ad libitum or moderate, unsupervised exercise — in free-living, middle-aged men. Compliance was determined at monthly measurement sessions through food records and activity logs; DEXA scans were performed every 3 months.Subjects/setting Fifty-eight overweight men (mean body mass INDEX=29.0±2.6; mean AGE=43.4±5.7 years) recruited from a national corporation were assigned randomly to diet, exercise, or control groups.Interventions One group reduced dietary fat to 26.4% of energy intake but kept activity unchanged; another group self-selected aerobic exercise (three sessions per week at 65% to 75% maximum heart rate) but kept diet unchanged. A control group maintained weight.Main outcome measures At 12 months, measurements of weight, total and regional fat mass and lean mass, energy intake, and percentage dietary fat; physical activity indexes. Statistical analyses Results were analyzed using paired t tests and analysis of variance.Results Mean weight loss was 6.4±3.3 kg in dieters and 2.6+3.0 kg in exercisers; control subjects maintained weight. DEXA scans revealed that 40% of dieters’ weight loss was lean tissue; more than 80% of weight lost by exercisers was fat. Exercisers maintained limb lean tissue and lost fat mass.Conclusions Greater total weight and lean tissue loss occurred when subjects lost weight through a low-fat diet consumed ad libitum than when subjects participated in unsupervised aerobic exercise. Use of DEXA enabled identification of progressive total and regional changes in fat and lean tissue. J Am Diet Assoc. 1997; 97:37–42. 相似文献
77.
Twin study of genetic and environmental effects on lipid levels 总被引:4,自引:0,他引:4
D L O'Connell R F Heller D C Roberts J R Allen J C Knapp P L Steele D Silove 《Genetic epidemiology》1988,5(5):323-341
A study of 106 pairs of monozygotic (MZ) and 94 pairs of dizygotic (DZ) twins tested the hypothesis that part of the previously described genetic influence on blood lipid levels can be ascribed to closer similarities among MZ than among DZ twin pairs in environmental factors that affect lipid levels. Participants were adult twin volunteers (age 17-66; 64 male and 136 female pairs) who were selected from the NH & MRC Twin Registry or were respondents to advertisements. They completed a 4-day weighed food diary from which mean nutrient intake was derived. Information on lifestyle and demographic variables was obtained by questionnaire and a nonfasting blood sample was taken for measures of total, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol and the HDL2 and HDL3 subfractions. Height and weight were measured, and body mass index (BMI) was calculated (kg/m2). Estimates of the heritability of sex-adjusted lipid levels were 0.72 for total cholesterol, 0.79 for HDL cholesterol, 0.69 for HDL2, 0.20 for HDL3, 1.06 for LDL cholesterol, and 0.44 for sex-adjusted BMI. In all cases except for HDL3, genetic variance was statistically significant. After adjusting for the effects of environmental variables in three different ways, the estimates of heritability were somewhat lower for total cholesterol, HDL2, and BMI, and those for HDL cholesterol (borderline) and LDL cholesterol (definitely) remained statistically significant but were decreased. A genetic influence on HDL3 was not found. Adjusted heritability estimates obtained from one method of analysis were 0.35 for total cholesterol, 0.49 for HDL, 0.04 for HDL2, -0.34 for HDL3, 0.66 for LDL, and 0.32 for BMI. These results suggest that the assumptions made in the classical twin study approach are not appropriate when examining genetic effects on lipid levels or BMI, or indeed on any biological variable that may be affected by environmental factors that tend to be more similar in MZ twins than in DZ twins. In these circumstances, more complex models may be needed to differentiate between genetic and environmental influences. 相似文献
78.
Williams C. A. Jones H. D. Freeman R. W. Wernke M. J. Williams P. L. Roberts S. M. James R. C. 《Regulatory toxicology and pharmacology : RTP》1994,20(3)
Reference doses (RfDs) and reference concentrations (RfCs) developed by the United States Environmental Protection Agency (USEPA) are typically used in the quantitation of risk of potential adverse human health effects from exposure to environmental chemicals. For a large number of chemicals, however, USEPA RfDs and RfCs have not yet been determined. Thus, for risk assessments that involve a large number of chemicals, there is insufficient toxicity information with which to evaluate potential adverse human health effects for all chemicals present at a particular site. Due to this insufficiency, the risk assessor must either (1) ignore potential exposures on the assumption that omitting these exposures does not significantly alter decisions concerning the remediation of the site or (2) undertake a lengthy and costly analysis to generate the necessary RfDs or RfCs. A potential solution to this problem is to develop estimated permissible concentrations (EPCs), values which represent permissible environmental concentrations or related acceptable daily dosages derived from occupational exposure limits. In the present analysis, acceptable daily dosages determined using the EPC method were compared to USEPA RfDs or RfCs which were converted to dosages based on standard exposure assumptions. Based on a comparative analysis of EPCs and USEPA reference values for 103 chemicals, it was found that EPC daily dosages represent a reasonably conservative surrogate value when USEPA or state reference values are unavailable. Given that there are hundreds of chemicals with occupational exposure limits but no state or USEPA reference values, acceptance of the EPC methodology would provide an interim solution for the problem of insufficient toxicity information for a substantial number of environmental chemical contaminants. 相似文献
79.
David A Todd MSc PhD John Kennedy FRACO † Sharyn Roberts RN Jane Watts RN Kim Psaila RN BApplSc Elizabeth John MD FRACP 《Clinical & experimental ophthalmology》1994,22(1):19-23
From January 1986 to December 1991 we examined the eyes of 206 infants born at Westmead Hospital, Neonatal Intensive Care Unit who were less than 29 weeks' gestation at birth to determine the incidence of retinopathy of prematurity. Eighty-five infants (41.3%) had no retinopathy of prematurity (ROP) in either eye, 82 infants had stages 1 or 2 ROP (39.8%), 29 had stage 3 ROP (14.1%) and 11 had stage 4 ROP (5.3%). Of these, cryotherapy was performed in 18; six now have bilateral retinal detachment and are blind The more severe stages of ROP were significantly associated with an increase in the number of days of oxygen supplementation, an increase in the number of days of mechanical ventilation and the presence of patent ductus arteriosus. Infants receiving steroids for mechanical ventilator dependence had a significantly greater chance of requiring cryotherapy (11 or 22 receiving steroids versus seven of 43 without steroids; P < 0.01). 相似文献
80.
J A SCUDAMORE MA MB BChir P J H Tooley MBBS MRCGP DRCOG R J Allcorn BSc DPhil MRPharmS 《International journal of clinical practice》1992,46(4):260-263
Vaginal candidosis is one of the most common infections of the vagina and the first accredited record of the disease appeared in 1849. Over the years the terms ‘candidiasis’ and ‘candidosis’ have been used, but it is generally accepted now that the terms are synonymous, and the term most commonly in use today is ‘candidosis’. Mainly caused by the yeast Candida albicans, the condition is characterised by intense inflammation of the vaginal mucosa and a curdy, off-white discharge; it is often associated with severe vulval itching and possibly burning pain. The severity of symptoms seems to vary greatly from patient to patient and the reason for this is unclear. It is suggested that in some patients there may be an element of hypersensitivity. Vaginal candidosis may occur in children but is most common in adults and only sometimes affects the elderly. The majority of women will suffer at least one attack of vaginal candidosis during their lifetime, and there are several predisposing factors such as diabetes, pregnancy and antibiotics. Some authorities consider the condition more frequent in those taking oral contraceptives or other hormones. 相似文献