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41.
Heather Warrack‐Goldman Betsy H. Brown Nancy J. Binkin 《Ecology of food and nutrition》2013,52(3):221-229
Nutritional surveys were conducted in three regions of Mauritania between September and November, 1983, to assess the impact of a severe drought and to determine priorities for relief assistance. Survey sites and children were chosen at random using established Centers for Disease Control survey methodology. A total of 1,498 children between the ages of 6 months and 5 years were weighed, measured and examined for xerophthalmia and scurvy. Information on age, sex, diarrhea, measles immunization, diet and food aid was collected for each child. Levels of acute malnutrition (< 80 % of median weight‐for‐height) ranged from 8.2 to 17.2% in the 3 regions, and both xerophthalmia and scurvy were seen. The children between 1 to 3 years of age had the highest levels of malnutrition. Food aid deliveries were irregular and inadequate in the two regions with the highest rates of malnutrition. Implications for targeting and choice of relief efforts are discussed. 相似文献
42.
Yehuda Limony Michael Friger Ze’ev Hochberg 《Journal of clinical research in pediatric endocrinology》2013,5(3):142-144
Objective: Pubertal gynecomastia (PG) occurs in up to 65% of adolescent boys. In this study, we investigated the relationship between the ages at which PG and peak height velocity occur in pubertal boys.Methods: This was a prospective study that was designed to detect PG within three months of its emergence. We examined one hundred and six boys who were followed for short stature and/or delayed puberty at three month intervals, and gynecomastia was observed in 43 of these boys (40.5%).Results: PG occurred in the 43 boys within a year of their peak height velocity, and most of these boys were at Tanner stage 3 for pubic hair and had testicular volumes between 8-10 mL.Conclusion: It is recommended that evaluation of height growth be included in the diagnostic approach to PG in boys with short stature and/or delayed puberty. The coincidence of age of peak height velocity and PG suggests a causal relationship between the two events and a role of insulin-like growth factor-1.Conflict of interest:None declared. 相似文献
43.
Mohammad A. Zafar Julia Fayanne Chen Jinlin Wu Yupeng Li Dimitra Papanikolaou Mohamed Abdelbaky Thais Faggion Vinholo John A. Rizzo Bulat A. Ziganshin Sandip K. Mukherjee John A. Elefteriades 《The Journal of thoracic and cardiovascular surgery》2021,161(2):498-511.e1
ObjectivesElucidating critical aortic diameters at which natural complications (rupture, dissection, and death) occur is of paramount importance to guide timely surgical intervention. Natural history knowledge for descending thoracic and thoracoabdominal aortic aneurysms is sparse. Our small early studies recommended repairing descending thoracic and thoracoabdominal aortic aneurysms before a critical diameter of 7.0 cm. We focus exclusively on a large number of descending thoracic and thoracoabdominal aortic aneurysms followed over time, enabling a more detailed analysis with greater granularity across aortic sizes.MethodsAortic diameters and long-term complications of 907 patients with descending thoracic and thoracoabdominal aortic aneurysms were reviewed. Growth rates (instrumental variables approach), yearly complication rates, 5-year event-free survival (Kaplan–Meier), and risk of complications as a function of aortic height index (aortic diameter [centimeters]/height [meters]) (competing-risks regression) were calculated.ResultsEstimated mean growth rate of descending thoracic and thoracoabdominal aortic aneurysms was 0.19 cm/year, increasing with increasing aortic size. Median size at acute type B dissection was 4.1 cm. Some 80% of dissections occurred below 5 cm, whereas 93% of ruptures occurred above 5 cm. Descending thoracic and thoracoabdominal aortic aneurysm diameter 6 cm or greater was associated with a 19% yearly rate of rupture, dissection, or death. Five-year complication-free survival progressively decreased with increasing aortic height index. Hazard of complications showed a 6-fold increase at an aortic height index of 4.2 or greater compared with an aortic height index of 3.0 to 3.5 (P < .05). The probability of fatal complications (aortic rupture or death) increased sharply at 2 hinge points: 6.0 and 6.5 cm.ConclusionsAcute type B dissections occur frequently at small aortic sizes; thus, prophylactic size-based surgery may not afford a means for dissection protection. However, fatal complications increase dramatically at 6.0 cm, suggesting that preemptive intervention before that criterion can save lives. 相似文献
44.
K. Vehik R. F. Hamman D. Lezotte J. M. Norris G. J. Klingensmith D. Dabelea 《Diabetic medicine》2009,26(10):961-967
Objective Studies have suggested that the age at diagnosis of Type 1 diabetes (T1D) is decreasing over time. The overload hypothesis postulates that risk factors, such as accelerated growth, may be responsible for this decrease. We assessed changes in age, body mass index (BMI), weight and height at diagnosis with T1D in non‐Hispanic white (NHW) and Hispanic (HISP) young people from Colorado, using data from the IDDM Registry and SEARCH Study. Methods In three time periods, 656 (1978–1983), 562 (1984–1988) and 712 (2002–2004) young people aged 2–17 years were newly diagnosed with T1D. Age, weight, height and presence of diabetic ketoacidosis (DKA) at diagnosis with T1D were obtained from medical records. Trends over the three time periods were assessed with regression analyses. Results Age at diagnosis decreased by 9.6 months over time (P = 0.0002). Mean BMI standard deviation score (SDS), weight SDS and height SDS increased over time (P < 0.0001), while prevalence of DKA decreased (P < 0.0001). Increasing height over time accounted for 15% (P = 0.04) of the decreasing age at diagnosis with T1D. Conclusions Our study provides evidence that increased linear growth, but not increased BMI or weight over time, may account, at least in part, for the younger age at diagnosis of T1D in Colorado children. This finding supports the hypothesis that increasing environmental pressure resulting from changes in potentially preventable risk factors may accelerate the onset of T1D in children. 相似文献
45.
目的:探讨2型糖尿病患者体质指数(BMI)、腰围(WC)、腰臀比(WHR)、腰围/身高比(WHtR)与血压、血脂的关系。方法调查191例2型糖尿病患者,测量身高、体重、腰围、臀围及血压,计算BMI、WHR、WHtR,测定总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C),分析上述四种体脂指标与2型糖尿病患者血压、血脂的关系。结果偏相关分析显示:BMI、WC、WHR、WHtR均与收缩压(SBP)独立正相关,其中WHtR相关性最强。BMI、WHtR均与舒张压(DBP)呈正相关。BMI、WC、WHR、WHtR异常组的SBP、DBP、TC、TG、LDL-C水平均较正常组偏高,HDL-C水平较正常组偏低。多元逐步线性回归表示WHtR为TG水平的影响因素。结论各体脂指标(BMI、WC、WHR、WHtR)与2型糖尿病患者的血压及血脂水平的改变有一定的相关性,对于减少2型糖尿病患者发生代谢综合征的风险而言,预防肥胖是至关重要的。 相似文献
46.
Summary The purpose of this study was to investigate whether young insulin-dependent diabetic patients still develop peripheral nerve dysfunction when using modern multiple insulin injection therapy and to elucidate if this correlated with various disease parameters. Seventy-five patients, 7 to 20 years old with a duration of diabetes of more than 3 years, and 128 age-matched healthy control subjects underwent bilateral studies of median, peroneal, and sural nerves. Presence of diabetes lowered motor conduction velocity (p<0.0001), sensory conduction velocity (p<0.0001) and sensory nerve action potential (p<0.05) in all examined nerves. The mean change in conduction velocity induced by diabetes was –4.8 m/s in the peroneal nerve, –3.3 m/s in the median motor nerve, –2.6 m/s in the sural nerve and –2.4 m/s in the median sensory nerve. Fifty-seven percent of the patients had abnormal conduction (values outside 95% predictive interval) which was seen most often in the motor nerves, especially in the peroneal nerve (41%) followed by the median nerve (24%). In multiple regression analysis, long-term poor metabolic control and increased body length correlated with nerve dysfunction identified in most examined parameters. Three patients had signs or symptoms suggestive of neuropathy. It is concluded that despite modern multiple insulin injection therapy, with reasonably good metabolic control, nerve dysfunction is still common in children and adolescents with insulin-dependent diabetes mellitus. Risk factors are increased height and long-term poor metabolic control.Abbreviations IDDM
Insulin-dependent diabetes mellitus
- MIT
multiple insulin injection therapy
- MCV
motor nerve conduction velocity
- CMAP
compound muscle action potential
- DML
distal motor latency
- SCV
sensory nerve conduction velocity
- SNAP
sensory nerve action potential 相似文献
47.
Neil M. Davies Stephanie von Hinke Kessler Scholder Helmut Farbmacher Stephen Burgess Frank Windmeijer George Davey Smith 《Statistics in medicine》2015,34(3):454-468
Instrumental variable estimates of causal effects can be biased when using many instruments that are only weakly associated with the exposure. We describe several techniques to reduce this bias and estimate corrected standard errors. We present our findings using a simulation study and an empirical application. For the latter, we estimate the effect of height on lung function, using genetic variants as instruments for height. Our simulation study demonstrates that, using many weak individual variants, two‐stage least squares (2SLS) is biased, whereas the limited information maximum likelihood (LIML) and the continuously updating estimator (CUE) are unbiased and have accurate rejection frequencies when standard errors are corrected for the presence of many weak instruments. Our illustrative empirical example uses data on 3631 children from England. We used 180 genetic variants as instruments and compared conventional ordinary least squares estimates with results for the 2SLS, LIML, and CUE instrumental variable estimators using the individual height variants. We further compare these with instrumental variable estimates using an unweighted or weighted allele score as single instruments. In conclusion, the allele scores and CUE gave consistent estimates of the causal effect. In our empirical example, estimates using the allele score were more efficient. CUE with corrected standard errors, however, provides a useful additional statistical tool in applications with many weak instruments. The CUE may be preferred over an allele score if the population weights for the allele score are unknown or when the causal effects of multiple risk factors are estimated jointly. © 2014 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. 相似文献
48.
Akane Anai Kimiyo Ueda Koichi Harada Takahiko Katoh Kumiko Fukumoto Chang-Nian Wei 《Environmental health and preventive medicine》2015,20(6):447-454
Objectives
To assess the difference between self-reported and measured weight values in Japanese men and women and to determine the underlying determinants of the differences between self-reported and measured values.Methods
The data were collected from 363 general Japanese individuals aged 16–88 years living in Kumamoto prefecture. Participants completed a self-administered questionnaire designed for this study with self-reported weight and height values. Measured weight and height were measured immediately after questionnaire completion. Paired t-tests identified differences between self-reported and measured values by sex. Multiple-stepwise regression analysis examined the independent variables’ effects on the differences between self-reported and measured weights.Results
Significant differences were found between self-reported and measured values for both sexes (p < 0.001). There was a significant negative relationship between the difference in an individual’s self-reported and measured weight in each sex, with higher measured weight individuals more likely to underestimate their weight. Multiple-stepwise regression analysis models explained 12.1 % (p < 0.01), 11.3 % (p < 0.01), and 5.6 % (p < 0.01) of the variance in all participants, men, and women, respectively. Significant effects were found for age, weight measurement frequency, and measured weight in total participants, weight measurement frequency, and measured weight for men, and age for women.Conclusions
In this study, the mean absolute value of the weight and height variances proved the unreliability of self-reported weight and height values. This study’s findings suggest self-reported weight inaccuracy especially for obese populations. This should be adjusted when using it in epidemiological studies and healthcare planning.49.
目的探讨注意力缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)儿童的骨龄发育水平与体质指数(body mass index,BMI),为ADHD开展有效的治疗与预防措施提供依据。方法采取自愿原则选自本院保健科心理门诊6~11岁的符合美国精神障碍诊断统计手册(DSM-Ⅳ)诊断标准的初诊ADHD儿童53例为观察组,生长发育门诊中选取正常健康儿童53例为对照组,采用数字化摄影仪拍摄左手腕骨正位X线片,用统一标准测量身高、体重,按CHN法(中国人手腕部骨发育评价标准)骨龄标准评价手腕骨龄片。结果观察组身高年龄与实际年龄的差均值(0.8±1.1)与对照组(-0.1±0.6)的比较差异有统计学意义(P0.001),骨龄与实际年龄差均值与对照组比较差异有高度统计学意义(P0.001),遗传身高与预测终身高的差均值(1.1±1.0)与对照组(1.0±0.4)比较差异无统计学意义(P0.05),BMI观察组(18.1±3.5)与对照组(16.2±2.3)两组均值比较差异有统计学意义(P0.05)。结论 ADHD儿童的骨龄发育水平较早,体质指数偏高,不影响成年身高。 相似文献
50.
《Annals of human biology》2013,40(6):554-556
AbstractBackground: Secular trends of increasing weight and height over past centuries are well documented in developed countries. However, these data are still scarce in developing countries such as Brazil.Aim: To verify the secular trends of height, weight and body mass index (BMI) of military students from Brazilian Army schools who were born between the 1920s and 1990s.Sample and methods: A retrospective study was performed, which included a survey of data from the files of two Army schools. The sample was composed of subjects aged between 18–20 years old.Results: The study analysed 2169 heights and 1741 weights and BMIs. During the evaluation period, height increased 7.3?cm, weight 9.8?kg and BMI 1.8?kg/m2. The most significant gains were observed in subjects born from the 1920s to the 1940s and the 1960s to the 1970s.Conclusion: Secular trends of growth in military students born in the 20th century were positive in Brazil, although increases were not constant decade-by-decade. 相似文献