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21.
BACKGROUND: We proposed diagnostic criteria for immune thrombocytopenic purpura (ITP) by modifying the existing guidelines for diagnosis of ITP and by incorporating laboratory tests found useful for predicting its diagnosis, for example erythrocyte count, leukocyte count, anti-GPIIb/IIIa antibody-producing B cells, platelet-associated anti-GPIIb/IIIa antibodies, percentage of reticulated platelets, and plasma thrombopoietin. OBJECTIVE AND METHODS: To validate our criteria, we conducted a multi-center prospective study involving 112 patients with thrombocytopenia and a morphologically normal peripheral blood film at the first visit. Each patient underwent a physical examination, routine laboratory tests, and specialized tests for the anti-GPIIb/IIIa antibody response and platelet turnover. RESULTS: Ninety-one patients (81%) satisfied the proposed criteria at first visit. Clinical diagnosis was made by skilled hematologists > 6 months after the first visit; ITP was diagnosed in 88 patients and non-ITP disorders in 24. The proposed criteria had 98% sensitivity, 79% specificity, a 95% positive predictive value, and a 90% negative predictive value. A relatively low specificity appears to be attributed to a few patients who had both ITP and aplastic anemia or myelodysplastic syndrome. CONCLUSIONS: Our preliminary diagnostic criteria based on ITP-associated laboratory findings were useful for the differential diagnosis of ITP, but additional evaluations and modifications will be necessary to develop criteria that can be used routinely.  相似文献   
22.
血栓的形成及中药抗栓溶栓概况   总被引:11,自引:0,他引:11  
血栓形成是由于正常的凝血机制的扰乱而促使某些血细胞和蛋白质被激活相互作用而最终导致血小板-纤维蛋白血栓的形成.AT-Ⅲ、PC、TM是体内重要的抗凝物质.白细胞与血小板的相互作用、PGI2/TXA2值以及许多疾病状态是影响血栓形成的诸因素.许多中药具有抗血小板聚集、抗血栓形成的作用,包括生物碱类,如小檗碱、北豆根碱和钩藤碱;中药蒲黄、花椒、沙棘、大蒜的提取物;一些中药复方等.  相似文献   
23.
棕榈油对成人血脂和血小板功能的影响   总被引:3,自引:0,他引:3  
张坚  王春荣 《营养学报》1997,19(2):186-190
报道了棕榈油(PA),花生油(PE)对血清总胆固醇水平(TC)在5.5~7.0mmol/L的受试者血脂和血小板功能的影响。51名受试者(男31人,女20人,年龄30~66岁之间)分为两组,一组男15人,女11人,称PE组;另一组男16人女9人,称PA组,预备期3周,膳食以当地日常食用的花生油烹调,实验期6周。PA组受试者食用以棕榈油烹调的实验膳;PE组受试者仍食花生油烹调的膳食。脂肪约占膳食能量的30%,其中60%~65%来自实验油。实验结果表明:与起始值相比,6周末PA组受试者血清TC,低密度脂蛋白胆固醇(LDL-C)和总胆固醇与高密度脂蛋白胆固醇比值(TC/HDL-C)显著下降,血浆血栓素B2(TXB2)/6-酮前列环素F1α、(6-keto-PGF1α)比值显著下降,全血血小板聚集率未见显著变化。PE组受试者的血脂、血浆TXB2、6-keto-PGF1α及全血血小板聚集率等指标均未出现显著变化。提示,棕榈油作为我国居民家庭烹调用油并不会增加发生心血管疾病的危险。  相似文献   
24.
卵巢恶性肿瘤与血小板增多关系分析   总被引:1,自引:0,他引:1  
目的探讨卵巢恶性肿瘤伴发血小板增多的临床规律。方法回顾分析98例卵巢恶性肿瘤患者的临床资料,26例合并血小板增多。结果血小板增多占26.5%,其中晚期(Ⅲ+Ⅳ期)占88.46%,晚期患者血小板偏高明显增多,且肿瘤切除后血小板下降。结论卵巢恶性肿瘤伴发血小板增多晚期患者多见,预后差,血小板增多可作为判断卵巢肿瘤恶性程度及术后随访的指标。  相似文献   
25.
26.
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   
27.
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   
28.
Heparin-induced Extracorporeal LDL-Precipitation (HELP) is an effective procedure for the elimination of both plasma LDL and fibrinogen. In 10 adult patients with severe type II hyperlipoproteinemia, a single HELP treatment of 3 1 plasma led to an acute decrease in the average plasma viscosity (PV) from 1.30 to 1.1 mPas. At the same time, an even more marked decrease in the mean erythrocyte aggregation rate from a pathological value of 7.9% to a value of 3.7% (normal range less than 5%) was observed. Long-term studies on five patients demonstrated a lasting improvement in these two haemorheological variables. The acute rheological changes were also accompanied by an improvement in polarographically determined muscle oxygen tension. Mean oxygen tension values measured in both the m.biceps brachii and the m.tibialis anterior in five patients before and after a single HELP treatment increased from 30 +/- 4 to 37 +/- 7 mmHg and from 27 +/- 2 to 31 +/- 3 mmHg respectively. These results may provide an explanation for the rapid improvement in patients' clinical symptoms such as angina pectoris and in stress electrocardiogram which have been observed during HELP therapy.  相似文献   
29.
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   
30.
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   
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