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101.
OBJECTIVE: To assess the impact of recent guidelines from the UK joint working party of child health surveillance recommending that all children be measured at age 5 and again between 7 and 9 years of age to determine how many normal school age children are likely to be referred for specialist assessment. METHODS: The longitudinal data of 486 children measured by school nurses in a community setting were examined and compared with measurements made in a research setting by a single, skilled observer. MAIN OUTCOME MEASURES: Number of children identified as having abnormal stature (< 0.4th or > 99.6th centile) and abnormal growth rate height standard deviation score (HSDS) change > 0.67). RESULTS: The community survey identified seven (1.4%) children as having abnormal stature (four short, three tall), 11 (2.3%) were identified as "slow growing", and nine (1.9%) increased their HSDS by more than 0.67. These results were comparable to data collected in ideal research conditions. CONCLUSIONS: Following the recommendations would not result in an excess number of inappropriate referrals. However, this study highlights several unresolved issues such as interobserver variability and time interval between measurements. A large scale prospective study should be considered to establish realistic and cost-effective criteria before implementation of a national screening programme.  相似文献   
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Natural and human-caused disasters, violence with weapons, and terrorist acts have touched directly the lives of thousands of families with children in the United States.1 Media coverage of disasters has brought images of floods, hurricanes, and airplane crashes into the living rooms of most American families, with limited censorship for vulnerable young children. Therefore, children may be exposed to disastrous events in ways that previous generations never or rarely experienced. Pediatricians should serve as important resources to the community in preparing for disasters, as well as acting in its behalf during and after such events.  相似文献   
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The purpose of this study was to investigate the circulatory responses to hypoglycaemia in diabetic and non‐diabetic children and to determine whether these changes were associated with hormone levels or clinical variables. Plasma glucose levels in 18 diabetic and 15 control children were gradually lowered to 2.5 (0.3)?mmol/L (mean (SD)) and 2.9 (0.2)?mmol/L, respectively. Blood pressure and heart rate were recorded at 10‐min intervals, and blood samples were taken for hormone analysis. Systolic pressure increased from 110.1 (10.0) to 115.0 (11.2)?mmHg (p=0.008) in the diabetic children and from 116.9 (12.0) to 121.6 (12.7)?mmHg (p=0.049) in the controls. Diastolic pressure decreased from 61.9 (6.7) to 55.5 (7.6)?mmHg (p<0.001) in the diabetic children and from 66.5 (6.3) to 55.1 (5.1)?mmHg (p<0.001) in the controls. The increase in pulse pressure during hypoglycaemia was significantly smaller in the diabetic children (10.6 (5.5) vs. 15.7 (7.7)?mmHg, p=0.04). The final systolic and pulse pressure correlated with the final adrenaline level in the controls (r=0.66, p=0.008 and r=0.70, p=0.003, respectively). In the non‐diabetic as well as the diabetic group, the increase in pulse pressure correlated with the increase in adrenaline (r=0.66, p=0.008 and r=0.50, p=0.03, respectively). It is concluded that systolic pressure increases and diastolic pressure decreases during hypoglycaemia in children. The smaller increase in pulse pressure observed in the diabetic children is probably related to a significantly smaller increase in adrenaline in this group.  相似文献   
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目的:探讨体外诱导骨髓间充质干细胞向胰岛素分泌细胞分化的可能性,并观察其动态变化。方法:实验于2005-09/2007-03在山东大学齐鲁医院完成。①标本来源:骨髓标本15例来自山东大学齐鲁医院成人骨髓检查结果正常者,均签署捐献同意书。②实验方法:无菌条件下取骨髓2.0~5.0mL,采用percoll分离液和贴壁法获得纯化的成人骨髓间充质干细胞。③实验评估:流式细胞仪行细胞表面抗原检测,在适当的条件下诱导其分化为成骨细胞和脂肪细胞。采用两步法向胰岛素分泌细胞诱导,观察其在碱性成纤维细胞生长因子、活化素A、胰岛素样生长因子、尼克酰胺等因子刺激下向胰岛素分泌细胞分化的动态变化。双硫踪染色鉴定胰岛样细胞团,酶联免疫吸附试验检测细胞分泌胰岛素的情况,RT-PCR检测胰岛细胞特异基因的表达。结果:①骨髓间充质干细胞的生长特性及免疫表型:分离培养获得的贴壁细胞,呈形态均一的梭形,流式细胞仪检测CD34、CD45表达阴性,CD29、CD44表达阳性。②向成骨细胞和脂肪细胞的诱导分化:此类细胞经茜素红染色、油红O染色均呈阳性,可诱导分化为成骨细胞和脂肪细胞。③向胰岛素分泌细胞的诱导分化:第1步诱导后出现细胞簇,双硫腙染色不着色,胰岛素分泌量少,仅检测到PDX-1基因的表达,证实其为胰岛前体细胞。第2步诱导后细胞簇数目逐渐上升,至诱导14d大部分细胞簇经双硫腙染色都呈红色。④诱导后培养上清中胰岛素含量:诱导第3,7,14,21天的胰岛素分泌量分别为(15.3±4.9),(34.1±5.6),(40.4±5.3),(39.8±5.1)mU/L。⑤胰岛细胞特异基因的表达:诱导7d仅检测到PDX-1基因的表达,insulin1、insulin2和Glut2基因均不表达。诱导14,21d检测到insulin2、PDX-1基因表达,insulin1基因弱表达,Glut2基因不表达。结论:体外分离、纯化得到的骨髓间充质干细胞诱导7d可分化出胰岛前体细胞,不具功能性;诱导14d后可成功地分化出成熟的具有功能性的胰岛素分泌细胞。  相似文献   
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外源性AA引起兔动脉条收缩,呈剂量依赖性;EPA抑制AA收缩血管亦呈浓度依赖性;DHA对AA收缩血管作用无明显影响。破坏血管内皮后AA收缩血管作用大为减弱,EPA抑制AA收缩血管作用也几乎消失。吲哚美辛能阻断AA收缩兔主动脉条的作用。兔主动脉6-keto-PGF、TXB2及其比值随AA浓度升高而增加,低剂量EPA对前列腺素类代谢无明显影响,较大剂量时则降低上述指标。  相似文献   
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目的:探讨乳腺癌组织中核呼吸因子-1(NRF-1)蛋白表达与乳腺癌发生、发展及临床病理特征的关系。方法:采用免疫组化EnVision二步法,对211例乳腺癌组织和50例乳腺良性病变组织中NRF-1蛋白表达进行检测。结果:NRF-1蛋白表达定位于细胞核,着色呈棕黄色,乳腺癌中阳性表达(82.7%)低于乳腺良性病变组织阳性表达(100%),χ2=100.288,P=0.000;高分化乳腺癌NRF-1阳性率明显高于中、低分化乳腺癌(χ2=16.242,P=0.001;χ2=72.802,P=0.000),中分化乳腺癌也明显高于低分化乳腺癌,χ2=30.190,P=0.000。乳腺癌淋巴结转移患者NRF-1蛋白阳性表达率明显低于未转移者,χ2=12.025,P=0.007;TNM分期中I期NRF-1蛋白阳性表达率明显高于Ⅱ、Ⅲ期,χ2=12.025,P=0.007。结论:NRF-1蛋白的表达可能与乳腺癌的发生发展密切相关,可作为乳腺癌患者疾病进展监控和预后观测的指标,具有临床应用价值。  相似文献   
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