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1.
Child benefits are typically paid from birth. This paper asks whether starting universal child benefits in pregnancy leads to improvements in infant health. Leveraging administrative birth registry and hospital microdata from England and Wales, I study the effects of the Health in Pregnancy Grant, a universal conditional cash transfer equivalent to three months of child benefit (190 GBP) as a lump sum to pregnant mothers from 2009 to 2011. I exploit quasi-experimental variation in eligibility with a regression discontinuity design in the date of birth of the baby. I find that the policy increased birth weight by 8–12 grams on average, reduced low birth weight (<2500 g) by 3-6 percent and decreased prematurity by 9–11 percent. Younger mothers, particularly those living in deprived areas, benefit the most. I present evidence that the mechanisms are unlikely to be antenatal care, nutrition or smoking, with reductions in stress remaining a possible explanation.  相似文献   
2.
The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed.  相似文献   
3.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
4.
5.
目的:山白树是中国特有珍稀濒危植物。分析微卫星特征,开发其微卫星分子标记。方法:采用Illumina二代测序技术建立山白树基因组文库和微卫星文库,分析微卫星组成类型,设计山白树引物,用5个山白树种群进行扩增和检测以分析其多态性。结果:二代测序共返回38,942,660条100 bp配对序列,通过质量修剪及拼接得到200,386条拼接序列,其中长度 335 bp的为7 614条;在7 614条序列中检测出微卫星位点694个,其中单核苷酸重复最多,单核苷酸重复中A/T重复数量最多;二核苷酸长度变异最大,其中AG/CT重复数量最多,重复长度变异情况与微卫星丰度呈正相关。为36条山白树微卫星重复次数高的序列设计引物,经聚合酶链式反应(PCR)扩增和聚丙烯酰胺凝胶电泳检测,20对引物多态性丰富且条带清晰,等位基因数(NA)在3~6之间,平均为4,多态性信息含量(PIC) 0. 535 5~0. 754 0,平均值0. 615 5。对5个山白树种群的群体遗传分析发现,该物种遗传多样性较高(h=0. 697 5,I=1. 436 8,HE=0. 702 2),种群遗传分化显著(Fst=0. 374)。结论:通过部分山白树的群体遗传也可以说明本次开发的引物可用性较好。该研究开发了山白树微卫星分子标记引物,为山白树分子遗传学奠定了基础。  相似文献   
6.
Despite orientation and mobility (O&M) being a significant factor determining quality of life of people with low vision or blindness, there are no gold standard measures or agreement on how to measure O&M performance. In the first part of this systematic review, an inventory of O&M outcome measures used by recent studies to assess the performance of orientation and/or mobility of adults with vision impairment (low vision and blindness) is presented. A wide variety of O&M outcome measures have been implemented in different fields of study, such as epidemiologic research and interventional studies evaluating training, assistive technology, vision rehabilitation and vision restoration. The most frequent aspect of outcome measures is efficiency such as time, distance, speed and percentage of preferred walking speed, followed by obstacle contacts and avoidance, and dis/orientation and veering. Other less commonly used aspects are target identification, safety and social interaction and self-reported outcome measures. Some studies employ sophisticated equipment to capture and analyse O&M performance in a laboratory setting, while others carry out their assessment in real-world indoor or outdoor environments. In the second part of this review, the appropriateness of implementing the identified outcome measures to assess O&M performance in clinical and functional O&M practice is evaluated. Nearly a half of these outcome measures meet all four criteria of face validity (either clinical or functional), responsiveness, reliability and feasibility and have the potential to be implemented in clinical or functional O&M practice. The findings of this review confirm the complicated and dynamic nature of O&M. Multiple measures are required in any evaluation of O&M performance to facilitate holistic assessment of O&M abilities and limitations of each individual.  相似文献   
7.
目的探讨中国9个城市(简称九市)4~7岁儿童乳恒牙替换及其与体格生长的关系,分析恒牙发育长期变化趋势。方法采用分层整群抽样的方法,以4~7岁儿童为调查对象,于2015年6—10月在北京、哈尔滨、西安(北片),上海、南京、武汉(中片),广州、福州、昆明(南片)九市进行横断面调查,共37973名儿童,其中男19035名,女18938名。6岁以下每6个月为1组,6~<7岁1岁为1组。现场检查乳牙脱落、恒牙萌出情况,测量身高、体重等,并依据2009年中国儿童生长标准计算体格指标Z分值。采用Probit概率单位回归方法计算换牙年龄。不同性别、地区、年龄分组组间比较采用χ2检验或t检验。并利用1995年中国九市儿童体格发育调查中乳恒牙替换相关数据,分析恒牙发育的长期变化趋势。结果九市37973名儿童随着年龄增长换牙率逐渐增加,从4.0~<4.5岁的0.6%(42/7568)增长至5.5~<6.0岁的30.3%(2295/7583),6.0~<7.0岁达到74.5%(5680/7627)。除4.0~4.5岁组外,无论城郊男童换牙率均低于女童(P均<0.05);城区换牙率(男5.5~<6.0岁、女4.5~<5.0岁组之后)略高于郊区,如6.0~<7.0岁组男童城郊分别为74.2%(1427/1924)、69.2%(1305/1885)(χ2=11.446,P<0.01)。九市儿童换牙年龄为6.00(95%CI:5.98~6.01)岁。换牙年龄的第3~97百分位变化范围为4.88~7.11岁。女童中位换牙年龄(5.94岁)早于男童(6.06岁);城区(5.94岁)早于郊区(6.05岁);北片(5.97岁)、中片地区(5.97岁)略早于南片地区(6.05岁)。已换牙儿童体重、身高、体质指数Z分值均高于未换牙儿童(0.35±1.17比0.03±1.13、0.32±1.00比0.03±1.02、0.23±1.16比0.04±1.13,t=20.81、21.67、12.09,P均<0.05)。与1995年相比,2015年5.0岁以后儿童换牙率明显提高,如城区男童6.0~<7.0岁组1995年为63.8%(1146/1796),2015年提高至74.2%(1427/1924)(χ2=46.748,P<0.01);中位换牙年龄2015年较1995年提前0.24岁。结论九市4~7岁儿童换牙年龄女童早于男童,城区早于郊区,北、中片早于南片地区。换牙早晚与体格生长水平有关。近20年换牙年龄存在小幅提前趋势。  相似文献   
8.
There is evidence that caesarean section delivery can impact on neonatal weight loss and weight gain patterns in the first 5 days of life. We conducted an integrative systematic review to examine the association of mode of delivery on early neonatal weight loss. Pubmed, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Excerpta Medica dataBASE, and Medical Literature Analysis and Retrieval System Online were searched for relevant papers published before June 2019. Reference lists from the relevant papers were then backwards and forwards searched. As neonatal weight loss was reported in different formats, a meta‐analysis could not be carried out. Most studies did not distinguish between elective and emergency caesarean sections or instrumental and nonassisted vaginal deliveries. Seven papers were included. All papers except one found that caesarean section was associated with higher weight loss in the early days of life. Two papers presented data from studies on babies followed up to 1 month. One study found that on day 25, babies born by caesarean section had significantly higher weight gain than those born vaginally, while another found that by day 28, babies born vaginally gained more weight per day (11.9 g/kg/day) than those born by caesarean section (10.9 g/kg/day; p = .02). Overall, infants born by caesarean section lost more weight than those born vaginally, but due to the small number of studies included, more are needed to look at this difference and why it may occur. This discrepancy in weight between the two groups may be corrected over time, but future studies will need larger sample sizes and longer follow‐up periods to examine this.  相似文献   
9.
目的:对应用低分子肝素钙与奥扎格雷联合对患有脑血栓疾病的患者实施治疗的临床效果进行研究。方法整群选择在该院2012年12月—2014年12月就诊的患有脑血栓疾病的患者86例,随机分为对照组和治疗组,每组43例。采用奥扎格雷对对照组患者实施治疗;采用低分子肝素钙与奥扎格雷联合对治疗组患者实施治疗。对比神经功能缺损评分在药物治疗前后的变化幅度、脑神经功能恢复正常时间和脑血栓药物治疗计划实施总时间、脑血栓疾病药物治疗效果、用药期间的不良反应人数。结果治疗组患者神经功能缺损评分在药物治疗前后的变化幅度明显大于对照组;脑神经功能恢复正常时间(9.66±2.41)d和脑血栓药物治疗计划实施总时间(13.28±2.14)d明显短于对照组(13.62±3.47)、(17.39±3.20)d;脑血栓疾病药物治疗效果(总有效率90.6%)明显优于对照组(总有效率69.8%);用药期间的不良反应人数(1例)明显少于对照组(8例)。结论应用低分子肝素钙与奥扎格雷联合对患有脑血栓疾病的患者实施治疗的临床效果非常明显。  相似文献   
10.
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
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