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排序方式: 共有1605条查询结果,搜索用时 62 毫秒
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J. Oliveira-Santos R. Santos C. Moreira S. Abreu L. Lopes C. Agostinis-Sobrinho G. Stratton J. Mota 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(8):783-792
Background and aimsThe long-term relations between excessive adiposity in early childhood and unfavourable cardiometabolic profiles in later ages are not yet completely understood. We aimed to assess the associations between birth weight (BW) and BMI from 6 months to 6 years of age, with biomarkers indicative of low-grade inflammation, insulin resistance and lipid profiles in adolescence.Methods and resultsRetrospective school-based study with 415 Portuguese adolescents (220 girls), mean age of 14.08 ± 1.6 years old. Anthropometric data from birth to 6 years old was extracted from individual child health book records. Actual weight and height were measured and BMI calculated. Participants were classified at each time point as normal weight or overweight according to WHO reference values. Biomarkers were obtained from venous blood samples. Linear regressions were used to explore the associations between the biomarkers and early life anthropometric indicators. From 2 years onwards, BMI associated positively with the inflammatory score and HOMA-IR in adolescence. Children who were overweight/obese from 2 to 6 years of age presented significantly higher inflammatory score and HOMA-IR later in adolescence. TC/HDL ratio was also positively associated with BMI from the age of 5 years onwards. The associations between BMI and cardiometabolic outcomes remained positive in adolescence, with overweight adolescents presenting a higher inflammatory score, HOMA-IR and TC/HDL than normal weight adolescents.ConclusionA high BMI from an early age was consistently associated with worse inflammatory and lipid profiles and insulin resistance in adolescence. No associations were found between BW and the same studied outcomes. 相似文献
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Critically ill patients often demonstrate that whole body oxygen consumption (VO2) is dependent on oxygen delivery (DO2). In this retrospective study, the relationship of VO2 to DO2 in patients with isolated head injury (HI, n = 18) was compared to that in patients with multiple trauma (MT, n = 60) without serious head injury. Mean pulmonary capillary wedge pressure, central venous pressure, arterial PCO2, cardiac index, and oxygen delivery were significantly lower in HI, but oxygen consumption was not different in the groups. In both groups, changes in DO2 (delta DO2) within each patient were significantly correlated with changes in VO2 (delta VO2) in that same patient. This relationship was not different between the HI patients, (delta VO2 = (0.20 +/- 0.02) delta DO2), and the MT patients (delta VO2 = (0.17 +/- 0.01) delta DO2). When these groups were further divided into those with high hematocrit (greater than 32%) and low hematocrit (less than 32%), HI patients with a low hematocrit demonstrated a steeper regression slope, with 26 +/- 3% of the DO2 change being reflected in the VO2 change. This was significantly greater than the slope in HI patients with high hematocrit (13 +/- 3%) and the MT patients at high (19 +/- 2%) or low (16 +/- 2%) hematocrits. These data show a correlation between changes in oxygen delivery and consumption that is similar in both head-injury patients and multiple trauma patients without serious head injury. This relationship was greatest in head-injured patients at low hematocrit. This relationship of VO2 and DO2 in both groups suggests an influence of neurohumoral factors rather than local tissue phenomena.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Most radionuclide methods for measuring cardiac volume require a determination of the blood radioactivity concentration. Thus, changes in blood radioactivity over time or during interventions might lead to spurious volume estimates unless blood radioactivity is serially measured. The effects of elevated epinephrine, posture and exercise on 99mTc-labeled blood radioactivity concentration were studied in 15 young (mean age = 28 yr) and 14 older (mean age = 68 yr) healthy males. An epinephrine infusion of 50 ng/kg/min resulted in a 4.1% +/- 1.0% increase in 99mTc-blood radioactivity (p less than or equal to 0.001) compared to baseline. Sitting increased blood radioactivity concentration by 12.3% +/- 3.0% (p less than 0.0002) compared to the supine position and peak supine bicycle exercise caused an 11.0% +/- 1.7% increase (p less than or equal to 0.0001) compared to supine rest. There was a significantly greater increase during peak supine exercise in the young compared to the older subjects (15.0% +/- 2.3% versus 6.3% +/- 2.0%, p less than or equal to 0.01). The mechanism of the increase in blood radioactivity concentration is uncertain, but presumably reflects the addition of hemoconcentrated red blood cells from the spleen and/or the loss of plasma volume. Failure to correct for the increased blood radioactivity concentration during exercise or pharmacological interventions will result in a significant error in serial measurements of cardiac volumes by methods requiring RBC radioactivity measurements. 相似文献
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W C Levy A F Jacobson M D Cerqueira D T Matsuoka F H Sheehan J R Stratton 《Journal of nuclear medicine》1992,33(9):1642-1647
The effects of region of interest (ROI) selection and correction for Compton-scattered photons using a buildup factor on radionuclide left ventricular volumes calculated by the Links method were compared in 19 humans with contrast ventriculography and in phantoms. Three different methods of ROI selection were compared: a manual ROI, a second derivative ROI and a 50% count-threshold ROI. In phantoms without Compton scatter correction, volumes were overestimated by 30% (manual ROI), 20% (derivative ROI) and 1% (count threshold ROI). In subjects, results without Compton scatter correction were similar with overestimates of 50% (manual ROI) and 20% (derivative ROI) and an underestimate by 3% (count threshold method). Correction for Compton-scattered photons with the use of a phantom-derived buildup factor resulted in improved accuracy for the manual ROI (+15%) and the derivative ROI (0%). A 50% count threshold ROI following interpolative background subtraction allows the accurate calculation of cardiac volumes without the need for scatter correction, while a second derivative ROI method requires a correction for Compton scatter with the use of a buildup factor. 相似文献
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The federal government supports a nationwide network of medical centers to evaluate promising therapies against the human immunodeficiency virus (HIV) and the opportunistic infections and cancers that characterize AIDS. Forty-five obstetricians from the 49 medical centers receiving federal research support for the conduct of AIDS-related clinical trials, in preparation for a meeting, provided summary information about the number and clinical status of the known HIV-infected pregnant women under their care and the prenatal screening policies for HIV infection at their institutions. In the 12-month period before December 1989, an estimated 1000-1801 HIV-infected women delivered at these centers. The majority (82%) were asymptomatic, 12% were symptomatic, and 6% had AIDS. Routine T-cell testing of infected women was done as part of prenatal care in only 30 of 45 centers. Pneumocystis carinii pneumonia was reported in 35 women. Zidovudine was administered during pregnancy in 29 women. Formal prenatal screening policies have been implemented at the majority (43 of 45) of the medical centers. Most of the infected women identified at these centers chose to continue the pregnancy. With the increasing incidence of HIV infection in women, information concerning the clinical and immunologic state of pregnant infected women and the present use of antiretroviral and other related therapeutics during pregnancy can guide the approach to women's health care and is crucial to the design and implementation of AIDS clinical trials. 相似文献