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IL Ackerman  CA Karn  SC Denne  GJ Ensing  CA Leitch 《Pediatrics》1998,102(5):1172-1177
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation.  相似文献   
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OBJECTIVES. To test for socioeconomic differences in some biological and behavioral risk factors for obesity in a representative and contemporary sample of adolescents. METHODS: Cohort study of 2 016 randomly selected 12- and 15-year-olds representative of Northern Ireland, studied in 2000. We tested for differences in obesity risk factors based on a priori hypotheses between adolescents from affluent (n=487) versus deprived (n=237) families. Potential risk factors were dietary energy and macronutrient intake, habitual physical activity, TV viewing and computer use, and physical fitness. RESULTS: Adolescents of higher socioeconomic status reported significantly lower habitual energy intake (210 kJ/kg/d SD 80 vs. 229 kJ/kg/d SD 91, p < 0.01); significantly higher levels of habitual physical activity (physical activity score 25.9 SD 16.6 vs. 20.9 SD 16.4, p < 0.001), and had significantly higher cardiorespiratory fitness (estimated VO2 max 46.2 ml/kg/min SD 8.4 vs. 43.4 ml/kg/min SD 8.3, p < 0.001). Prevalence of overweight and obesity (BMI >85th percentile) in the cohort was 29.1% and was slightly but not significantly higher in the low (33.8%) versus the high (28.5%) socioeconomic groups. CONCLUSIONS: Differences in some of the biological and behavioral risk factors for obesity exist between adolescents of different socioeconomic status in Northern Ireland. These may help explain the basis of established socioeconomic differences in obesity risk.  相似文献   
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真菌性角膜角膜溃疡发病率逐年上升,目前主要采用抗真菌药物治疗、手术治疗、抗真菌药物联合手术治疗以及中西结合治疗,尚无特效的治疗方法。本文就治疗该病的最新进展进行了综述。  相似文献   
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目的:通过创建无烟医院活动,了解医生的吸烟状况和控烟知识、态度与行为,并对干预效果进行评价。方法:在北京、上海、广州选择60家医院创建无烟医院,对全院医生开展控烟干预,在干预前对19580名医生、干预后对20772名医生进行问卷调查,了解医生的吸烟状况和控烟知识、态度与行为的变化。结果:通过一年的控烟干预,医生吸烟率由...  相似文献   
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随着器官移植体液免疫理论的发展与抗体检测技术的进步,抗体介导的排斥反应(AMR)已逐渐被认识和引起关注。其治疗难度大、逆转率较低,已成为导致移植物失功的重要原因。本文较为系统地介绍了AMR的免疫机制、诊断与防治进展,以及供者特异性抗体的检测技术和临床意义,从而提出供者特异性抗体是引起移植物排斥反应特别是慢性排斥反应的主要原因,移植受者需常规监测抗体以利及时干预和治疗。  相似文献   
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目的探讨右美托咪定用于腹腔镜子宫切除术全麻维持的效果。方法选取该院进行腹腔镜子宫切除术患者100例,随机分为两组,研究组气管插管后静脉泵注右美托咪定;对照组不使用右美托咪定。结果研究组的自主呼吸恢复时间、气管导管拔出时间、术后清醒时间优于对照组(P〈0.05)。结论右美托咪定静脉泵注用于全麻维持可缩短患者的全麻复苏时间,效果显著。  相似文献   
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Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs.  相似文献   
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