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31.
Sex differences in reading performance have been considered a relatively stable phenomenon. However, there is no general agreement about their neural basis, which might be due to that sex differences are largely influenced by age. This paper focuses on the sex differences in the reading-related neural network of Chinese children and its interaction with age. We also attempt to predict reading abilities based on neural network. Fifty-three boys and 56 girls (8.2–14.6 years of age) were recruited. We collected their resting-state fMRI and behavioural data. Restricted sex differences were found in the resting-state reading neural network compared to extensive age by sex interaction effect. Specifically, the interactions between sex and age indicated that with increasing age, girls showed greater connectivity strength between visual orthographic areas and other brain areas within the reading network, while boys showed an opposite trend. After controlling age, the prediction models of reading performance for the girls mainly included interhemispheric connections, while the intrahemispheric connections (particularly the phonological route) mainly contributed to predicting the reading ability for boys. Taken together, these findings suggest that sex differences in reading neural networks are modulated by age. Partialling out age, boys and girls also show the stable sex differences in relationship between reading neural circuit and reading behaviour.  相似文献   
32.
The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) maintains a database of extremely preterm infants known as the Generic Database (GDB). Begun in 1987, this database now includes more than 91,000 infants, most of whom are extremely preterm (<29 weeks gestation). The GDB has been the backbone of the NRN, providing high quality, prospectively collected data to study the changing epidemiology of extreme prematurity and its outcomes over time. In addition, GDB data have been used to generate hypotheses for prospective studies and to develop new clinical trials by providing information about the numbers and characteristics of available subjects and the expected event rates for conditions and complications to be studied. Since its inception, the GDB has been the basis of more than 200 publications in peer-reviewed journals, many of which have had a significant impact on the field of neonatology.  相似文献   
33.
PurposeTo compare the outcomes of patients with gastrointestinal neuroendocrine tumor liver metastases treated with liver-directed therapy (LDT) to those treated with systemic therapy (ST) in a statewide cancer database.Materials and MethodsA retrospective study was performed of patients with metastatic gastrointestinal tract neuroendocrine tumors treated with either LDT or ST alone between the years 2000–2012 in the California Cancer Registry. Overall survival and disease-specific survival were assessed using multivariable Cox proportional hazards analysis and propensity score matching.ResultsA total of 154 patients (ST, n = 87 and LDT, n = 67) were studied. The median overall survival and disease-specific survival for patients that received ST was 29 and 35 months versus 51 and >60 months for patients that received LDT. On multivariate analysis, LDT and the resection of the primary tumor were associated with improved survival (hazard ratio [HR] 0.52, P = .002; HR 0.43, P = .001). Non-white race, Medicaid/uninsured status, and the presence of lung metastases were associated with poor survival (HR 1.76, P = .014; HR 2.29, P = .009; and HR 1.79, P = .031). Propensity score matching demonstrated an improvement in disease-specific survival for LDT compared to ST (HR 0.53, P = .036). The improvement in overall survival on propensity score matching did not achieve statistical significance (HR 0.70, P = .199).ConclusionsLDT is associated with improved overall and disease-specific survival as compared to ST in patients with gastrointestinal neuroendocrine tumor liver metastases. Further investigation is needed to determine whether combination or sequential treatment can improve outcomes in this population.  相似文献   
34.
Macrophage colony-stimulating factor (CSF1) is the primary growth factor required for the control of monocyte and macrophage differentiation, survival, proliferation and renewal. Although the cDNAs encoding multiple isoforms of human CSF1 were cloned in the 1980s, and recombinant proteins were available for testing in humans, CSF1 has not yet found substantial clinical application. Here we present an overview of CSF1 biology, including evolution, regulation and functions of cell surface and secreted isoforms. CSF1 is widely-expressed, primarily by cells of mesenchymal lineages, in all mouse tissues. Cell-specific deletion of a floxed Csf1 allele in mice indicates that local CSF1 production contributes to the maintenance of tissue-specific macrophage populations but is not saturating. CSF1 in the circulation is controlled primarily by receptor-mediated clearance by macrophages in liver and spleen. Administration of recombinant CSF1 to humans or animals leads to monocytosis and expansion of tissue macrophage populations and growth of the liver and spleen. In a wide variety of tissue injury models, CSF1 administration promotes monocyte infiltration, clearance of damaged cells and repair. We suggest that CSF1 has therapeutic potential in regenerative medicine.  相似文献   
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ObjectiveTo analyze the relationship between nutritional status measured by anthropometry and the mental, psychomotor and language development of infants in marginalized rural areas of Mexico.MethodCross-sectional study with 576 infants aged from 7 to 26 months in four rural locations. Variables consisted of measures of anthropometric and cognitive development.ResultsInfants with short stature had a lower rate of language development, while birth weight was marginally associated with psychomotor development.ConclusionAlthough acute malnutrition (identified by underweight) is no longer a problem in rural areas of Mexico, chronic malnutrition (expressed as stunting) is still common and is associated with alterations in mental development in the child population.  相似文献   
38.
Oral appliances (OAs) have demonstrated efficacy in treating obstructive sleep apnea (OSA), but many different OA devices are available. The Japanese Academy of Dental Sleep Medicine supported the use of OAs that advanced the mandible forward and limited mouth opening and suggested an evaluation of their effects in comparison with untreated or CPAP. A systematic search was undertaken in 16 April 2012. The outcome measures of interest were as follows: Apnea Hypopnea Index (AHI), lowest SpO2, arousal index, Epworth Sleepiness Scale (ESS), the SF‐36 Health Survey. We performed this meta‐analysis using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. Five studies remained eligible after applying the exclusion criteria. Comparing OA and control appliance, OA significantly reduced the weighted mean difference (WMD) in both AHI and the arousal index (favouring OA, AHI: ?7·05 events h?1; 95% CI, ?12·07 to ?2·03; P = 0·006, arousal index: ?6·95 events h?1; 95% CI, ?11·75 to ?2·15; P = 0·005). OAs were significantly less effective at reducing the WMD in AHI and improving lowest SpO2 and SF‐36 than CPAP, (favouring OA, AHI: 6·11 events h?1; 95% CI, 3·24 to 8·98; P = 0·0001, lowest SpO2: ?2·52%; 95% CI, ?4·81 to ?0·23; P = 0·03, SF‐36: ?1·80; 95% CI, ?3·17 to ?042; P = 0·01). Apnea Hypopnea Index and arousal index were significantly improved by OA relative to the untreated disease. Apnea Hypopnea Index, lowest SpO2 and SF‐36 were significantly better with CPAP than with OA. The results of this study suggested that OAs improve OSA compared with untreated. CPAP appears to be more effective in improving OSA than OAs.  相似文献   
39.
目的 探讨新一代基因测序平台(HiSeq2000)在甲基丙二酸血症(MMA)诊断中的价值.方法 1.采集已经临床确诊的9例MMA患儿外周血并提取DNA,将设计好的基因捕获探针与患儿DNA文库混合,然后利用基因捕获联合高通量测序分析技术对有机酸代谢相关的48个基因全部外显子区域进行测序.2.获得原始数据,去除接头和过滤低质量数据,对数据进行SNP、InDel等分析,并采用Sanger测序方法对异常位点进行测序验证.3.气相色谱-质谱联用分析技术对尿液标本的有机酸测定及其他辅助检查.结果 1.突变基因:7例存在MMACHC基因突变,7例患儿中共检测出7种突变,包括c.482G>A、c.567_568insT、c.609G>A、c.440_ 441del、c.80A>G、c.315C>G、c.90G>A,其中c.440_441 del为未见报道突变;1例存在甲基丙二酰辅酶A变位酶(MUT)基因突变,均为内含子异常,分别是c.754-1G>C、c.1677-1G>A,其中c.754-1G>C为未见报道突变;1例未检测到突变.2.临床症状:9例患儿均存在智力运动发育迟缓,伴抽搐3例,反复顽固性代谢性酸中毒、头痛及面瘫、反复性溶血各1例.脑电图异常9例,头颅磁共振异常8例,尿液中甲基丙二酸水平均升高(273.4 ~146 022.8倍),血同型半胱氨酸水平增高8例(27.13~ 396.84 μmol/L,正常<20 μmol/L).3.Sanger测序验证:均符合新一代测序平台结果,无假阳性存在.结论 1.进一步证明c.609G>A突变位点为中国MMA合并同型半胱氨酸血症患儿的热点突变位点.MMA基因突变类型较多,与临床症状无明显相关性.2.推测MMACHC基因c.440_441 del突变及MUT基因c.754-1G>C突变为新发突变.3.基因捕获联合高通量基因测序技术一次性捕获突变基因数量大,获取疾病的遗传信息量广,具有高通量、高灵敏度、高效等特点,适合于MMA患儿检测,也可为其他儿科临床常见遗传性疾病的检测提供参考.  相似文献   
40.
目的检测3-8岁阻塞性睡眠暂停低通气综合征(obstructive sleep apnea-bypopnea sgn-drome,OSAHS)儿童血清性激素水平,探讨其性激素变化与下丘脑—垂体—性腺轴(hypothalamic-pituitary-gonad axis,HPGA)启动的关系。方法以76例3-8岁符合 OSAHS 的儿童和40例3-8岁健康儿童为研究对象,检测血清睾酮(T)、雌二醇(E2)、卵泡刺激素(FSH)、黄体生成素(LH)及催乳素(PRL)水平,对其 HPGA 启动、体格发育情况进行对比,分析性别、低氧、体重指数(BMI)与性激素水平之间的关系。结果OSAHS 组儿童身高、体重水平明显低于对照组(P <0.05),E2水平明显高于对照组(P <0.01)。OSAHS 组男童 FSH 水平明显低于对照组(P <0.01)。OSAHS 组女童 FSH 水平明显高于 OSAHS 组男童(P <0.01)。结论OSAHS 可能影响儿童身高、体重,OSAHS 可能影响 E2、FSH 的分泌,3-8岁 OS-AHS 儿童体内雌激素的负反馈调节敏感性高,HPGA 尚未启动。  相似文献   
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