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81.
本文采用实验研究方法,通过对大鼠运动后红细胞数量,Hb浓度及体重等一般情况的检测,拟对其施加不同负荷的训练,观察训练后大鼠红细胞膜流动性及红细胞膜脂质成分的变化,进一步讨论运动后红细胞功能及机体机能所发生的变化。实验结果表明,小负荷的运动训练通过改善RBCM脂质组成,增加p/c比值、增强其抗氧化能力等增加RBCM流动性,使红细胞的变形能力增加,有利于其运氧功能的发挥。大负荷训练后RBCM流动性下降,提示不同负荷的运动训练会引起机体产生不同的变化,进而导致机体运动水平上的差异,整体携氧能力下降。 相似文献
82.
早期下床活动的必要性已得到大家认可,但术后早期病人常常较虚弱,且下床活动时会引发一些不适,病人也会有一些担心和顾虑,这在一定程度上会影响病人下床活动的积极性。颈椎手术本身有其特殊性,术后对颈部的稳定要求较高,因此此类病人活动有其特点。本研究以颈椎术后已下床活动的病人为研究对象,通过问卷调查,了解颈椎手术后病人首次下床的感受和相关需求,为进一步提高颈椎术后护理质量提供依据。1资料和方法1.1对象采用方便取样,选取2005年4月—2005年6月在某三甲医院因颈椎病入院、术后已下床活动的病人75例。其中男54例,女21例;年龄28岁~7… 相似文献
83.
Interrupting reperfusion as a stroke therapy: ischemic postconditioning reduces infarct size after focal ischemia in rats. 总被引:18,自引:0,他引:18
Heng Zhao Robert M Sapolsky Gary K Steinberg 《Journal of cerebral blood flow and metabolism》2006,26(9):1114-1121
Cerebral ischemic preconditioning protects against stroke, but is clinically feasible only when the occurrence of stroke is predictable. Reperfusion plays a critical role in cerebral injury after stroke; we tested the hypothesis that interrupting reperfusion lessens ischemic injury. We found for the first time that such postconditioning with a series of mechanical interruptions of reperfusion significantly reduces ischemic damage. Focal ischemia was generated by permanent distal middle cerebral artery (MCA) occlusion plus transient bilateral common carotid artery (CCA) occlusion. After 30 secs of CCA reperfusion, ischemic postconditioning was performed by occluding CCAs for 10 secs, and then allowing for another two cycles of 30 secs of reperfusion and 10 secs of CCA occlusion. Infarct size was measured 2 days later. Cerebral blood flow (CBF) was measured in animals subjected to permanent MCA occlusion plus 15 mins of bilateral CCA occlusion, which demonstrates that postconditioning disturbed the early hyperemia immediately after reperfusion. Postconditioning dose dependently reduced infarct size in animals subjected to permanent MCA occlusion combined with 15, 30, and 60 mins of bilateral CCA occlusion, by reducing infarct size approximately 80%, 51%, and 17%, respectively. In addition, postconditioning blocked terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling-positive staining, a marker of apoptosis, in the penumbra 2 days after stroke. Furthermore, in situ superoxide detection using hydroethidine suggested that postconditioning attenuated superoxide products during early reperfusion after stroke. In conclusion, postconditioning reduced infarct size, most plausibly by blocking apoptosis and free radical generation. With further study it may eventually be clinically applicable for stroke treatment. 相似文献
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Lü Zhuo-ren 《中国人民解放军军医大学学报》2006,21(5)
Objective: To compare renal sodium transport, using fractional excretions of lithium(FELi) as a marker of proximal tubule sodium reabsorption, between hypertensive and non-hypertensive ouabain-treated rats and further to elucidate the role of ouabain in pathogenesis of hypertension. Methods: Thirty male Sprague-Dawley rats weighting 180-200 g were randomly divided into normal control group and ouabain treated group. Rats were infused with 1 ml/kg·d normal saline or 27. 8μg/kg·d ouabain in-traperitoneally once a day respectively. Systolic blood pressure (SBP), heart rate and body weight were recorded weekly. Rats were sacrificed 6 weeks after treatment. Blood and 24-hour urine sample were collected to measure the serum and urinary concentration of sodium, trace lithium and creatinine. Endogenous creatinine clearance rate(Ccr), fractional excretions of sodium (FENa), fractional excretions of lithium (FELi) and fractional reabsorption of sodium in the postproximal tubules (FDRNa) were calculated. Ouabain levels of plasma and renal tissue, plasma renin activity, angiotensin I and aldosterone concentration were determined. Results: 65% of the ouabain-treated rats achieved significantly higher SBP after 4 weeks, compared with that of the saline control groups or self baseline (P<0. 01). But in the other 35% of the ouabain-treated rats, their SBP was similar with control group during the experiment (P>0. 05). The body weight, heart rate and food intake between the 3 groups were no significant differences (P> 0. 05). FELi and FDRNa were significantly lower in ouabain-hypertensive group compared with ouabain-non-hypertensive group and control group(P<0. 01 and P<0. 05). The FEu and FDRn, of ouabain-nonhyper-tensive groups were similar with control group(P>0. 05). Ccr and FENa were comparable between the 3 groups (P>0. 05). Plasma and renal tissue ouabain levels, plasma renin activity, angiotensin I and aldosterone contents in ouabain-hypertensive rats were comparable with ouabain-nonhypertensive rats. Conclusion: Increase of proximal tubule sodium reabsorption play an important role in the pathogenesis of ouabain-hypertensive rats. The change of renal sodium transport may result from regulation to renal Na+ , K + -ATPase by ouabain. 相似文献
87.
Noriyo Kimura Satomi Yonemoto Toshihiko Machiguchi Xuan Li Hideki Kimura Haruyoshi Yoshida 《Hypertension research》2006,29(8):573-580
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis. 相似文献
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89.
多发性硬化患者血清尿酸水平变化的研究 总被引:2,自引:0,他引:2
目的 探讨多发性硬化 (MS)患者血清尿酸 (UA)水平的变化及其临床意义。方法 采用酶定量分析法对 4 3例MS患者和 4 5名正常对照者的血清UA水平进行检测。结果 MS组血清UA水平明显低于对照组 (P <0 0 1)。MS组中病程越长 (P <0 0 1)、神经伤残程度越重 (DSS评分越高 ) (P <0 0 5 ) ,血清UA水平越低 ;女性患者UA水平明显低于男性患者 (P <0 0 0 1) ;经过糖皮质激素治疗后血清UA水平明显回升 (P <0 0 0 1) ,但治疗前血清UA水平越低则疗效越差 (P <0 0 1、P <0 0 5 )。结论 MS患者血清UA水平降低 ,且与MS的病程、伤残程度、疗效及性别密切相关。UA水平升高可能为激素治疗MS的一个作用机制 相似文献
90.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献