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101.
John A. Morrison Philip R. Khoury Barbara N. Campaigne W. M. Cameron Chumlea Bonny Specker Barbara N. Campaign Shumei S. Guo 《American journal of human biology》1994,6(4):481-490
The purpose of this study was to compare estimates of body composition in two ethnic groups, 31 black and 38 white girls 10 through 16 years of age, to establish accurate and precise laboratory standards for field measures of body composition in the NHLBI Growth and Health Study HC 55025. The dual energy X-ray absorptiometry (DXA) measures of fat free mass (FFM) and % body fat (%BF) were made using Hologic QDR-1000/W. Corresponding values of FFM and %BF from underwater weighing (UWW) were determined using the two-component model of Siri, and these were corrected using the model of Lohman for white girls only. In the comparison of the different models and methods, the two-component model overestimated FFM compared to estimates from DXA for black girls, as did the corrected Lohman model for white girls. The two-component model significantly overestimated %BF in both white and black girls compared to corresponding estimates from DXA. The ratio of bone mineral content (BMC)/FFM affected the degree of %BF differences in black girls but not in white girls. Also, as the density of FFM increased or approached adult status in black girls (BMC/FFM increased), differences between the two-component model and estimates from DXA decreased. In both groups of girls, the relationship of %BF from UWW and DXA are a function of the level of body fatness. DXA values of %BF are greater than those from UWW under about 24% body fat, but the converse occurs above 25% body fat. The inability of UWW using the two-component model to account for the body composition in these girls can be corrected in part by measuring the variables for a multicomponent model or more easily by using DXA estimates of body composition. © 1994 Wiley-Liss, Inc. 相似文献
102.
103.
Birch S 《Health and social service journal》1985,95(4947):576-577
104.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献
105.
To determine whether a food's acceptability changes with time of day and degree to which a food is appropriate for a given mealtime, preferences were obtained both in the morning and the afternoon for a set of foods which included items appropriate "for breakfast", "for dinner", or for either mealtime. A second purpose of the study was to determine whether such cultural rules regarding food appropriateness had been acquired by preschool children and whether the pattern of shifting acceptability with time of day predicted for adult subjects would also appear in the preference data of the children. Participants included 25 adults and 30 three- and four-year-old children. All subjects were seen twice, once in the morning and once in the late afternoon for two identical sessions. Half of the subjects in each age group were seen first in the morning, half were seen first in the afternoon. In these sessions food preferences for the set of foods varying in mealtime appropriateness were assessed and the foods were categorized as "for breakfast" of "for dinner". The preference data of both the adults and the children showed significant preference shifts with time of day, with breakfast items more preferred in the morning than the afternoon and dinner items more preferred in the morning than the afternoon. These shifts were larger for adults than for children but not significantly so. 相似文献
106.
Dalia Khoury Alexander Preiss Paul Geiger Mohd Anwar Kevin Paul Conway 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundThe opioid crisis in the United States may be exacerbated by the COVID-19 pandemic. Increases in opioid use, emergency medical services (EMS) runs for opioid-related overdoses, and opioid overdose deaths have been reported. No study has examined changes in multiple naloxone administrations, an indicator of overdose severity, during the COVID-19 pandemic.ObjectiveThis study examines changes in the occurrence of naloxone administrations and multiple naloxone administrations during EMS runs for opioid-related overdoses during the COVID-19 pandemic in Guilford County, North Carolina (NC).MethodsUsing a period-over-period approach, we compared the occurrence of opioid-related EMS runs, naloxone administrations, and multiple naloxone administrations during the 29-week period before (September 1, 2019, to March 9, 2020) and after NC’s COVID-19 state of emergency declaration (ie, the COVID-19 period of March 10 to September 30, 2020). Furthermore, historical data were used to generate a quasi-control distribution of period-over-period changes to compare the occurrence of each outcome during the COVID-19 period to each 29-week period back to January 1, 2014.ResultsAll outcomes increased during the COVID-19 period. Compared to the previous 29 weeks, the COVID-19 period experienced increases in the weekly mean number of opioid-related EMS runs (25.6, SD 5.6 vs 18.6, SD 6.6; P<.001), naloxone administrations (22.3, SD 6.2 vs 14.1, SD 6.0; P<.001), and multiple naloxone administrations (5.0, SD 1.9 vs 2.7, SD 1.9; P<.001), corresponding to proportional increases of 37.4%, 57.8%, and 84.8%, respectively. Additionally, the increases during the COVID-19 period were greater than 91% of all historical 29-week periods analyzed.ConclusionsThe occurrence of EMS runs for opioid-related overdoses, naloxone administrations, and multiple naloxone administrations during EMS runs increased during the COVID-19 pandemic in Guilford County, NC. For a host of reasons that need to be explored, the COVID-19 pandemic appears to have exacerbated the opioid crisis. 相似文献
107.
JC Bos R Stoeckart AIJ Klooswijk B van Linge R Bahadoer 《Surgical and radiologic anatomy : SRA》1994,16(3):253-258
Summary In view of the increasing popularity of the direct lateral approach to the hip joint for hemi- or total hip arthroplasty, the location of the superior gluteal nerve (SGN) was studied. This nerve is in danger when using a transgluteal incision. In 20 embalmed specimens the relation of the SGN to the tip of the greater trochanter (TT) was studied as well as the relation to the iliac crest. For this purpose macroscopy, microscopy and CT were used. In 13 hips a so-called most inferior branch was found at an average of 1 cm distal to the inferior branch, the main trunk of the nerve. There was substantial variation in the course of both the inferior and the most inferior branch of the SGN. In order to prevent nerve damage, proximal extension of the transgluteal incision should be limited to 3 cm cranial to TT. Furthermore the incision has to be confined to the distal one third of the distance TT-iliac crest. In tall people extra care should be taken.
Anatomie chirurgicale du nerf glutéal supérieur et bases anatomo-radiologiques de l'abord latéral direct de la hanche
Résumé Les recours de plus en plus fréquent à la voie latérale directe de la hanche pour les prothèses totales ou cervico céphaliques nous a conduit à étudier la localisation du nerf glutéal supérieur (SGN) qui est exposé lors de l'incision transglutéale. Les rapports du SGN avec le sommet du grand trochanter (TT) et avec la crête iliaque ont été étudiés sur 20 cadavres embaumés. Nous avons eu recours à l'étude macroscopique, microscopique ainsi qu'au scanner. Dans 13 cas nous avons mis en évidence une branche très inférieure, donc plus distale, située 1 cm en moyenne en dessous de la branche inférieure habituelle de bifurcation du tronc principal. Il existait des variations importantes dans les trajets de ces deux branches inférieures. Afin de prévenir une lésion chirurgicale du nerf, l'incision transglutéale ne doit pas aller au delà de 3 cm du sommet du grand trochanter, de plus l'incision doit être confinée en dessous du tiers distal de la ligne joignant le grand trochanter à la crête iliaque.相似文献
108.
B M Churchill G A McLorie A E Khoury P A Merguerian A M Houle 《The Urologic clinics of North America》1990,17(2):343-360
Posterior urethral valves have a broad spectrum of clinical severity determined by the degree and reversibility of the long stepwise sequence of secondary pathology. Neonatal azotemia and severe bilateral reflux are particularly important negative prognostic factors. In the mild cases, valve ablation with or without delayed reconstruction is good therapy. In the very severe cases, our interpretation of all the clinical and experimental information now available suggests that the time interval and the level of decompression are extremely important. Achievement of consistent low caliceal pressure without stasis and infections should be achieved as soon as possible. We do not agree with the philosophy of "valve ablation and wait and see" for secondary reconstruction as applied to the severe cases. An analogous philosophy would be treating all respiratory infections as upper respiratory infections and applying aggressive appropriate therapy for pneumonia only if the patient does not respond clinically. However, all controversy aside, the management of neonatal infants with posterior urethral valves remains a difficult and challenging problem for us all. The real challenge will be to improve published management results to the point that the family faced with decisions regarding an in utero diagnosis of posterior urethral valves will have enough hope to continue the pregnancy. 相似文献
109.
To each according to need: a community-based approach to allocating health care resources. 总被引:1,自引:0,他引:1
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OBJECTIVE: To develop a method of allocating publicly funded health care resources among communities according to their relative levels of need for health care independent of their current patterns of use. DESIGN: For each health care program population mean levels of resource allocation were calculated and were adjusted for age and sex to produce a national age- and sex-adjusted share of program resources. Indices of relative need for health care (for most programs the standardized mortality ratio) were derived from existing data on aspects of illness and death and were then used to weight the age- and sex-adjusted shares for between-community differences in health risks and health care needs. SETTING: The populations of the 49 counties in Ontario were used as the communities among which resources were allocated. Health care expenditures in 1988-89 by the Ontario Ministry of Health were used as the "budget." MAIN RESULTS: Age- and sex-adjusted resource allocations weighted for between-community differences in health care needs differed from allocations based on population size, in certain cases by up to 100%. CONCLUSION: Existing data can be used to propose allocations of health care resources that relate to relative levels of need for care across communities. 相似文献
110.
Results of a year-long prospective audit of all arthroscopies of the knee in one NHS Trust hospital indicate that selective magnetic resonance imaging (MRI) would be cost-effective in up to 40% of patients. However, to achieve such savings, at least 14% of patients who would otherwise need diagnostic arthroscopy would need to be excluded from surgery, the cost of MRI must be low, and the success rate of interpreting the scans should be known. 相似文献