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21.
McGrath  HE; Liang  CM; Alberico  TA; Quesenberry  PJ 《Blood》1987,70(4):1136-1142
We have previously reported that lithium chloride (LiCl) stimulates the production of granulocyte-macrophage colony-forming cells (GM-CFC), pluripotent stem cells (CFU-S), and differentiated granulocytes, macrophages and megakaryocytes in murine Dexter marrow cultures and that this effect appears to be mediated indirectly by a radioresistant adherent marrow cell. In this study we have established that exposure of murine Dexter cultures to LiCl (4 mEq/L) causes an increase of colony-forming cell megakaryocytes (CFU-meg) over 1 to 6 weeks of culture in both supernatant (188% to 611%) and stromal phases (123% to 246%). Moreover, we have shown that lithium treatment of either irradiated (1,100 rad) or unirradiated stromal cells increased production of activities stimulating formation of megakaryocyte, granulocyte, macrophage, and mixed lineage colonies and proliferation of the factor-dependent cell line, FDC-P1. This FDC-P1 stimulatory activity was completely blocked by an antibody to purified recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF). The baseline or lithium-induced--stromal-derived bone marrow colony stimulating activity was partially blocked by the antibody to rGM-CSF and by an antibody to purified colony stimulating factor I (CSF-1); the two antibodies combined resulted in greater than 90% inhibition of the lithium-induced marrow stimulatory activity. In addition, radioimmunoassay (RIA) showed that although CSF-1 was detectable in supernatants of these cultures, exposure to lithium did not increase CSF-1 levels. These data indicate that Dexter stromal cells produce CSF- 1 and GM-CSF and that lithium appears to exert its stimulatory effects on in vitro myelopoiesis by inducing production of GM-CSF.  相似文献   
22.
目的探讨急性阑尾炎多层螺旋CT征象与血清炎性标志物的关系。方法收集2012年1月至2013年12月于同济大学附属杨浦医院经手术病理证实的具有完整临床及影像资料的急性阑尾炎患者66例,对所有患者的急性阑尾病变程度行CT分级,分析其与患者白细胞(WBC)计数、中性粒细胞百分比(NEUT%)及血清C反应蛋白(CRP)水平的相关性。结果急性阑尾炎CT分级与患者WBC计数与CRP水平呈正相关(P0.05),穿孔性阑尾炎患者NEUT%及CRP水平明显高于其他患者。CRP水平与阑尾直径、阑尾积液、回盲部变化、阑尾周围炎性条纹、小肠积液呈正相关(P0.05),WBC计数与回盲部变化及阑尾周围炎性条纹呈正相关(P0.05)。结论WBC计数及CRP水平与急性阑尾炎CT分级有关,CRP对急性阑尾炎的诊断及其严重程度的判断更有优势;CRP、NEUT%是穿孔性阑尾炎的重要预测因子,WBC可以更好地发现早期阑尾周围的炎性反应,综合分析CT表现与血清炎性标志物能更准确地诊断急性阑尾炎。  相似文献   
23.
目的研制可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统,为骨转移瘤提供新型的局部药物缓释系统。方法α-CSH-nano-HA/PHBV-PEG载顺铂制成可注射用α-CSH-nano-HA/PHBV-PEG cis-platinum缓释微球,研究其结构、释药特性、可注射性以及力学性能。结果(1)第1、3、5、7天缓释微球的释药浓度分别为97.5、90.7、83.2、68.5μg/mL,第7天后趋于稳定。(2)可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统在液固比为0.7时可注射性强,与此同时缓释药系统随着液固比的增大凝固时间延长。结论α-CSH-nano-HA/PHBVPEG顺铂释药系统具有良好的注射性能和缓释作用。  相似文献   
24.
目的 评估定量三维彩色能量多普勒超声(three-dimensional color power Doppler ultrasound,3D-CPD)联合β-HCG检查对胎盘功能低下的诊断价值.方法 选择2012年5月至2014年3月在昆明医科大学第四附属医院接受产检的产妇368例,利用GE公司E8三维超声系统对胎盘的血管化指数(VI)、血流指数(FI)和血管化-血流指数(VFI)进行测量,同时利用化学发光法测定β-HCG水平.并存产后记录新生儿体长、体重和生命体征综合评分(Apgar评分).结果 产后共有58例新生儿体重<2 500 g,为观察组,另外3 10例新生儿体重>2 500 g,为对照组.对照组VI、FI和VFI分别为(12.5±5.6)、(47.2±3.3)和(9.0±2.6),观察组为(10.2±4.8)、(40.6±4.1)和(4.2±1.7),差异具有统计学意义(P<0.05);观察组β-HCG水平为(29453.0±229.5) mIU/mL,中位数≥2.5 mom,对照组β-HCG水平为(8 442.6±47.2) mIU/mL,中位数<2.5mom,观察组β-HCG水平明显高于对照组(P<0.05);新生儿基本情况相比,观察组新生儿体长、体重和Apgar评分明显低于对照组(P<0.05).结论 3D-CPD联合β-HCG检查对胎盘功能异常具有重要的诊断价值,有利于围产期了解胎盘功能及估计胎儿预后.  相似文献   
25.
26.
塔娜  李思 《中国医疗设备》2020,(3):160-163,170
美国食品和药物管理局(Food and Drug Administration,FDA)经过多年发展和改革,已形成了成熟的上市前监管体系。本文通过对FDA上市批准路径(上市前批准、上市前通告、人道主义用器械豁免)和申报流程进行系统介绍,总结了加强事前沟通、降低产品风险等级和设立实质审查程序三个方面的启示,希望我国监管机构能充分吸收美国FDA对于医疗器械监管的经验和教训,建立适合中国国情的医疗器械监管体系,确保公众用器械安全。  相似文献   
27.

Aims/hypothesis

We validated the metabolic syndrome (MetS) score by confirmatory factor analysis (CFA) in children, middle-aged men, and older women and men and by investigating the relationships of the MetS score to incident type 2 diabetes, myocardial infarction, and cardiovascular and overall death in middle-aged men.

Methods

We assessed the core features of MetS, calculated the MetS score using z scores for waist circumference, insulin, glucose, triacylglycerols, HDL-cholesterol and blood pressure, and carried out CFA to investigate whether MetS represents a single entity in population samples of 491 children, 1,900 middle-aged men, 614 older women and 555 older men from Finland. We also followed-up incident type 2 diabetes for 11 years and other outcomes for 17–18 years in middle-aged men.

Results

We carried out second-order CFAs in which the MetS was represented by a second-order latent variable underlying four latent variables characterised by abdominal obesity, insulin resistance, dyslipidaemia and raised blood pressure in different age groups. These second-order factors and factors derived from first-order CFA using previously proposed models were strongly associated with a composite MetS score in all age groups (r?=?0.84–0.94) and similarly predicted type 2 diabetes, cardiovascular outcomes and mortality in middle-aged men. The risk of type 2 diabetes, myocardial infarction, cardiovascular death and overall death increased 3.67-, 1.38-, 1.56- and 1.44-fold, respectively, for a 1 SD increase in the MetS score.

Conclusions

The MetS can be described as a single entity in all age groups. The MetS score is a valid tool for research evaluating cardiometabolic risk in different age groups. Further research is needed to define cut-off points for risk estimation in clinical practice.  相似文献   
28.
29.
Abstract Background: We studied the associations of clustering of metabolic risk factors with plasma levels of alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) in healthy prepubertal children. Methods: The subjects were a representative population sample of 492 children 6-8 years of age. We assessed body fat percentage (dual-energy X-ray absorptiometry), body mass index, waist circumference, systolic and diastolic blood pressure, glucose, insulin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, ALT, GGT, and high-sensitivity C-reactive protein (hsCRP) and calculated a continuous metabolic syndrome score variable. We also used factor analysis to examine whether high-normal liver enzymes are a feature of metabolic syndrome among children. Results: Children with overweight or obesity, defined by International Obesity Task Force (IOTF) criteria, had a 2.1-times higher risk of having ALT and a 4.5-times higher risk of having GGT in the highest fifth of its distribution than normal weight children. Children in the highest sex-specific third of metabolic syndrome score, body fat percentage, waist circumference, and insulin had a two to three times higher risk of being in the highest fifth of ALT and GGT. Moreover, children in the highest third of glucose and hsCRP had a 2.5-fold risk of being in the highest fifth of GGT. First-order factor analysis yielded three factors; the first included insulin, glucose, and triglycerides; the second waist circumference, insulin, GGT, and hsCRP; and the third HDL-C, triglycerides, waist circumference, and insulin. Second-order factor analysis yielded a single metabolic syndrome factor, explaining 64.1% of the variance. Conclusions: Clustering of metabolic risk factors, particularly excess body fat, is associated with high-normal levels of ALT and GGT in prepubertal children. High-normal levels of liver enzymes, especially GGT, and systemic low-grade inflammation could be considered features of metabolic syndrome among children. Subtle changes in liver function may play an important role in the pathogenesis of metabolic syndrome beginning in childhood.  相似文献   
30.
目的 探讨骨质疏松症中医体质与辨证分型之间的相关性。方法 按照中西医诊断标准,将确诊的骨质疏松症患者进行中医体质分类与中医辨证分型的临床研究,找出其相关性与规律性,并进行总结。 结果 对300例患者进行中医辨证分型发现脾胃气虚证最多,占总病例数的23.00%,其次为肝肾不足证,占22.00%,以后依次为肾阳虚证、肾阴虚证、气血不足证、血瘀证、骨痿证、肝气郁结证、痰湿证、湿热证;在9种体质分类中阴虚质发病率排在第一位,其次为气虚质,以后依次为阳虚质、血瘀质、特禀质、平和质、痰湿质、湿热质与气郁质。结论 提示9种中医体质中阴虚质与气虚质发病率较高, 辨证分型中发病率较高的2个证型是脾胃气虚型与肝肾阴虚型。说明了体质类型与OP发病率有密切的相关性。  相似文献   
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