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31.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage. 相似文献
32.
Yang Hee Kim Young In Moon Young Hee Kang Jung Sook Kang 《Nutrition Research And Practice》2007,1(4):298-304
This study was conducted to investigate the hypocholesterolemic effect of simvastatin (30 mg/kg BW) and antioxidant effect of coenzyme Q10 (CoQ10, 15 mg/kg BW) or green tea (5%) on erythrocyte Na leak, platelet aggregation and TBARS production in hypercholesterolemic rats treated with statin. Food efficiency ratio (FER, ADG/ADFI) was decreased in statin group and increased in green tea group, and the difference between these two groups was significant (p<0.05). Plasma total cholesterol was somewhat increased in all groups with statin compared with control. Plasma triglyceride was decreased in statin group and increased in groups of CoQ10 and green tea, and the difference between groups of statin and green tea was significant (p<0.05). Liver total cholesterol was not different between the control and statin group, but was significantly decreased in the group with green tea compared with other groups (p<0.05). Liver triglyceride was decreased in groups of statin and green tea compared with the control, and the difference between groups of the control and green tea was significant (p<0.05). Platelet aggregation of both the initial slope and the maximum was not significantly different, but the group with green tea tended to be higher in initial slope and lower in the maximum. Intracellular Na of group with green tea was significantly higher than the control or statin group (p<0.05). Na leak in intact cells was significantly decreased in the statin group compared with the control (p<0.05). Na leak in AAPH treated cells was also significantly reduced in the statin group compared with groups of the control and CoQ10 (p<0.05). TBARS production in platelet rich plasma was significantly decreased in the groups with CoQ10 and green tea compared with the control and statin groups (p<0.05). TBARS of liver was significantly decreased in the group with green tea compared with the statin group (p<0.05). In the present study, even a high dose of statin did not show a cholesterol lowering effect, therefore depletion of CoQ10 following statin treatment in rats is not clear. More clinical studies are needed for therapeutic use of CoQ10 as an antioxidant in prevention of degenerative diseases independent of statin therapy. 相似文献
33.
Platelet factor 4 ( PF4) is a negativehematopoietic factor.It can inhibit the prolifera-tion of endothelial cells and hematopoietic stem/progenitor cells,particularly megakaryoryocyticcells,reversibly[1] ,inhibit DNA synthesis,blockcell cycle progression during S phase and reducethe sensibility of normal hematopoietic stem/pro-genitor cells,but not some cancer or leukemia celllines,to cytotoxic drugs and ionizing radia-tion[2 - 3] ,and it also can cause a population in-crease of the stem cel… 相似文献
34.
There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets. 相似文献
35.
P B Schneider U Denk M Breitenbach K Richter P Schmid-Grendelmeier S Nobbe M Himly A Mari C Ebner B Simon-Nobbe 《Clinical and experimental allergy》2006,36(12):1513-1524
BACKGROUND: Alternaria alternata is one of the most important allergenic fungi worldwide. Mannitol dehydrogenase (MtDH) has previously been shown to be a major allergen of Cladosporium herbarum and cross-reactivity has been demonstrated for several fungal allergens. OBJECTIVE: The present study's objective was to clone the MtDH from an A. alternata cDNA library, express and purify the recombinant non-fusion protein and test its IgE-binding properties. Methods A cDNA library prepared from A. alternata hyphae and spores was screened for mannitol dehydrogenase by DNA hybridization with the radioactively labelled C. herbarum homologue as a probe. The resulting clone was sequenced and heterologously expressed in Escherichia coli as a recombinant non-fusion protein, which was purified to homogeneity and analysed for its IgE-binding capacity. RESULTS: The coding sequence of the full-length cDNA clone comprises 798 bp encoding a protein with a molecular mass of 28.6 kDa and a predicted pI of 5.88. Protein sequence analysis revealed an identity of 75% and a homology of 86% between the MtDHs of A. alternata and C. herbarum. The functional mannitol dehydrogenase was expressed in the E. coli strain BL21(DE3) transformed with the vector pMW172 and purified to homogeneity. The enzyme catalyses the NADPH-dependent conversion of d-fructose to d-mannitol. In IgE-ELISA and immunoblots, MtDH is recognized by 41% of A. alternata-allergic patients. In vivo immunoreactivity of the recombinant MtDH was verified by skin prick testing. Finally, inhibition-ELISA experiments confirmed cross-reactivity between the MtDHs of A. alternata and C. herbarum. CONCLUSION: Mannitol dehydrogenase (Alt a 8) represents an important new allergen of the ascomycete A. alternata that might be suitable for improving diagnostic and therapeutic procedures. 相似文献
36.
Immune reactivity towards insulin, its amyloid and protein S100B in blood sera of Parkinson's disease patients 总被引:1,自引:0,他引:1
K. R. Wilhelm K. Yanamandra M. A. Gruden V. Zamotin M. Malisauskas V. Casaite A. Darinskas L. Forsgren L. A. Morozova-Roche 《European journal of neurology》2007,14(3):327-334
Peripheral immune responses can be sensitive indicators of disease pathology. We evaluated the autoimmune reactions to endocrine (insulin) and astrocytical (S100B) biomarkers in the blood sera of 26 Parkinson's disease (PD) patients compared with controls by using ELISA. We found a statistically significant increase of the autoimmune responses to both antigens in PD patients compared with controls with a mean increase of 70% and 50% in the autoimmune reactions towards insulin and S100B, respectively. Heterogeneity of the immune responses observed in patients may reflect the modulating effect of multiple variables associated with neurodegeneration and also changes in the basic mechanisms of individual autoimmune reactivity. We did not detect any pronounced immune reactions towards insulin amyloid fibrils and oligomers in PD patients, indicating that an amyloid-specific conformational epitope is not involved in immune recognition of this amyloid type, while sequential epitope of native insulin is hidden within the amyloid structures. Immune reactions towards S100B and insulin may reflect the neurodegenerative brain damaging processes and impaired insulin homeostasis occurring in PD. 相似文献
37.
袁苏徐 《苏州大学学报(自然科学版)》2005,25(1):107-109
目的探讨急性胰腺炎(AP)时血小板计数的变化规律及其临床意义。方法回顾性分析AP不同病程、严重程度、性别、年龄的血小板计数变化的特点。结果AP发病第1天中有49%的患者血小板计数<100×109/L,该比例随后逐渐下降(r=-0.85);平均血小板计数在起病的前2周内呈上升趋势(r=0.96),且不同发病天数间的平均血小板计数有显著差异(P<0.01)。病程中后期,部分患者的血小板计数>300×109/L,其比例随病程时间延长而升高(r=0.83);上述变化在不同性别中无明显差异,但≥60岁的患者中血小板计数<100×109/L的比例明显高于<60岁者(P<0.05)。重症胰腺炎(SAP)患者发病前3天首次血小板计数<100×109/L的比例(57%)明显多于轻症AP患者(19%,P<0.001),病程中血小板计数>300×109/L的比例(29%)也明显多于轻症患者(7%,P<0.001)。如以发病后首次血小板计数<100×109/L为标准预测SAP,其敏感性59%,特异性81%,阳性预测值51%,阴性预测值85%。结论AP发病时血小板计数有下降趋势,随着病程延长,血小板计数有增高趋势,血小板计数<100×109/L对预测SAP有较高的特异性。 相似文献
38.
云南白药对血小板活化的研究 总被引:9,自引:0,他引:9
罗琪 《福建中医学院学报》2004,14(2):12-14
为探讨云南白药对血小板活化的影响 ,应用单克隆抗体法 ,并用流式细胞仪对 2 0 6例男性腹股沟斜疝患者血小板活化分子标志物进行检测 ,同时检测血浆凝血物质和 D-二聚体含量。结果显示 :服药组血小板明显活化与对照组比较有显著性差异 ( P<0 .0 5 ) ,凝血物质和 D-二聚体与对照组比较无差异 ( P>0 .0 5 )。结论 :云南白药能增加血小板活化 ,促进局部止血 ,但它不影响凝血物质和 D-二聚体的含量 ,不增加血栓形成的危险。 相似文献
39.
应用鸡卵清蛋白致敏和刺激小鼠复制过敏性气道炎症反应模型研究血小板激活因子选择性拮抗剂YM-264对抗原引起气道嗜酸性粒细胞(EOS)浸润的影响。结果发现,正常小鼠支气管肺泡灌洗液(BALF)中未见到EOS;致敏小鼠给予抗原多次反复吸入刺激后,BALF中EOS急剧增多。在YM-264治疗各组中,YM-264的不同剂量分别导致EOS数下降27.0%、48.2%及67.9%。还发现YM-264抑制EOS对气道的浸润伴随着白细胞介素(IL)-5水平的明显下降。提示YM-264通过抑制IL-5的产生从而抑制了EOS在气道的聚集。 相似文献
40.
茶色素对冠心病及高血压病病人血小板功能的影响 总被引:1,自引:0,他引:1
目的:探索茶色素对冠心病、高血压病病人血小板功能的影响。方法:冠心病病人36例(男性21例,女性15例;年龄64±s4a);高血压病病人30例(男性18例,女性12例;年龄58±8a)。采用茶色素250mg,po,tid,30d为一个疗程。结果:治疗后TXB2下降,6-keto-PGP1α上升,TXB2/6-keto-PGF1α比值下降(P<0.01或P<0.05),GMP-140下降(P<0.05),PagT,PadT下降(P<0.05)。结论:茶色素具有降低血小板表面活性作用,抑制血小板聚集和粘附,抗血栓形成,改善微循环,对冠心病和高血压病病人起到积极的防治作用。 相似文献