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1.
Women with pre-eclampsia have an increased risk of cardiovascular disease later in life. The aim of the study was to establish the presence and pattern of arterial stiffness in women previously with pre-eclampsia from a semi-rural region of South Africa. This was a prospective longitudinal study which involved 36 previously pre-eclamptic women and 86 non-pregnant controls (NPC) who had a past history of non-complicated pregnancy. Maternal wave reflection (augmentation index) and carotid-femoral pulse wave velocity were assessed noninvasively, using applanation tonometry with the SphygmoCor device. Endothelial function was assessed by EndoPAT 2000 device; pneumatic probes were fitted to the index fingers; induced flow-mediated reactive hyperemia; the ratio of the readings before and after occlusion was then used to calculate the score, the reactive hyperemia index (RHI) as a measure of endothelial function.

Pulse wave velocity remained significantly higher in previously pre-eclamptic women than non-pregnant controls up to three months after delivery (p < 0.05), then it reduced to nonsignificant values. All blood pressure indices (central and brachial pressures), were higher in previously pre-eclamptic women as compared to nonpregnant controls up to one year postpartum.

Regional (aortic) arterial stiffness, though it persists for some time after delivery, is transitory in previously pre-eclamptic women from the rural Africa setting. However, their increase blood pressure is an indication of compromised arterial compliance in women previously with pre-eclampsia.  相似文献   

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脐血单个核细胞在半固体培养基中向神经元样细胞的分化   总被引:2,自引:0,他引:2  
为观察脐血单个核细胞在甲基纤维素半固体培养基中的生长情况 ,常规方法分离脐血单个核细胞 ,接种于含 SCF、GM-CSF、G-CSF、IL-3、IL-6、EPO的甲基纤维素半固体培养基中培养。第 5 d发现有 6~ 10个细胞组成的小集簇 ,散在分布 ,细胞形态无变化。第 11d有神经元样细胞生长 ,与集簇并存。以后神经元样细胞逐渐生长 ,但集簇生长停滞 ,第 16d仍未发现集落形成。收集细胞 ,进行神经元特异烯醇化酶 (NSE)、神经丝蛋白 (NF)免疫细胞化学测定 ,显示少量神经元样细胞 NSE、NF阳性。该结果提示在半固体培养基中 ,脐血单个核细胞可向神经元样细胞分化 ,传统的用于集落培养的半固体培养基可能也适合脐血中其它细胞成分的生长  相似文献   
3.
本文介绍一种以平面热解石墨电极为工作电极,用于识别人类白血病白细胞的半微分伏安型生物传感器。综合使用作者提出的四个电化学识别指标(氧化峰电位Ep,不同扫描电位下氧化峰电位的差值ΔEp,膜上单位细胞数的氧化峰电流Ip/cels以及氧化扫描与还原扫描相应的出峰情况),实现了对人类正常与异常白细胞、各种临床分型白血病白细胞的识别。  相似文献   
4.
半导体红外激光光凝治疗视网膜静脉阻塞   总被引:7,自引:0,他引:7  
为探讨半导体红外激光对视网膜静脉阻塞(RVO)的治疗效果,对58例RVO患者用Keeler公司“Microlase”半导体激光器(波长810nm)作区域封闭或全视网膜光凝(PRP)。结果:17例中央视网膜静脉阻塞(CRVO)患者,治疗前后平均视力分别为0.175及0.40;7例半球阻塞(Semi-CRVO)患者治疗前后平均视力为0.116及0.40;34例视网膜分枝静脉阻塞(BRVO)患者则分别为0.19及0.465。经t检验,差别均有显著性。结论:激光光凝治疗是RVO重建供氧平衡的重要手段,疗效肯定。半导体红外激光有比氩激光更易穿透浑浊介质和更少影响视网膜神经纤维层和黄斑功能等优点。早期进行区域封闭或全视网膜光凝,有利于保存有用视力。  相似文献   
5.
思维方式的转换与中药“半仿生提取法”   总被引:65,自引:9,他引:65  
在对该法试论的基础上,进一步从思维方式的角度论述。  相似文献   
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Neglect patients' performance during cancellation tasks is characterized by left sided omissions and, in many cases, by the production of inappropriate material of various kinds in the ipsilesional space, e.g. additional marks over already cancelled targets, marks drawn away from targets, scribbles, irrelevant drawings. It is unclear whether these behaviours, which have collectively been called perseverative, are functionally and anatomically connected and whether they correlate with the severity of neglect. Here we report a retrospective study on 33 right brain damaged patients with neglect after right hemisphere lesions in whom we measured the intensity of perseveration of the three following kinds: (1) ‘additional marks' (AM) perseveration where patients cancelled a target with two or more well separated marks; (2) ‘scribble’ perseveration, where patients, instead of cancelling the target with a single pen stroke as required by the task, performed multiple pen strokes without breaking the pen-to-paper contact, with the final product being a scribble; (3) ‘flying marks’ (FM) perseveration where patients produced cancellation marks well away from the targets. We found that AM and FM perseveration correlated with neglect severity, while ‘scribble’ perseveration did not. The lesion-symptom mapping showed three separate anatomical areas in the right hemisphere: ‘scribble’ perseveration was associated with lesions of the orbitofrontal cortex and caudate nucleus; AM perseveration was associated with damage to the rolandic operculum, superior temporal gyrus and inferior frontal gyrus; FM perseveration was associated with damage to the dorsal premotor cortex and the temporal pole. Neglect severity followed damage to a region which grossly corresponds to the sum of the regions associated with AM and FM perseveration respectively. This complex behavioural and anatomical pattern is interpreted in terms of a three-factor model, in which AM perseveration is caused by a deficit of disengagement of attention from the right side (also causing omissions), FM perseveration is caused by directional hypokinesia (also causing left-side omissions), and ‘scribble’ perseveration is the consequence of a failure to inhibit an initiated motor act, which is completely separate (both anatomically and functionally) from the disorder inducing omissions.  相似文献   
10.
Although xenografts have always held immeasurable potential as an inexhaustible source of donor organs, immunological barriers and physiological incompatibility have proved to be formidable obstacles to clinical utility. An exciting, new regenerative medicine‐based approach termed “semi‐xenotransplantation” (SX) seeks to overcome these obstacles by combining the availability and reproducibility of animal organs with the biocompatibility and functionality of human allografts. Compared to conventional xenotransplantation wherein the whole organ is animal‐derived, SX grafts are cleansed of their antigenic cellular compartment to produce whole‐organ extracellular matrix scaffolds that retain their innate structure and vascular channels. These scaffolds are then repopulated with recipient or donor human stem cells to generate biocompatible semi‐xenografts with the structure and function of native human organs. While numerous hurdles must be still overcome in order for SX to become a viable treatment option for end‐stage organ failure, the immense potential of SX for meeting the urgent needs for a new source of organs and immunosuppression‐free transplantation justifies the interest that the transplant community is committing to the field.  相似文献   
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