HIE患儿血小板参数变化及临床意义

检测并比较缺氧缺血性脑病（HIE）患儿（HIE组）及足月正常新生儿（对照组）的PLT计数、血小板平均体积（MPV）和血小板体积分布宽度（PDW）。结果显示HIE组PLT随病情加重而下降（P〈0．05,〈0．01）,MPV、PDW随病情加重而升高（P〈0．05）。与对照组比较,HIE组急性期PLT明显降低（P〈0．01）,MPV和PDW明显升高（P〈0．05）;HIE恢复期PLT、MPV和PDW无明显差异（P〉0．05）。提示检测HIE患儿血小板参数,可作为临床判断其病情严重程度的指标。     

溃疡性结肠炎患者P-选择素和血小板参数分析

背景：研究发现凝血机制活化在炎症性肠病（IBD）的进展过程中起重要作用。P-选择素（CD62P）参与介导凝血和炎症反应时中性粒细胞和单核细胞与活化的血小板或内皮细胞的黏附。目的：探讨血小板活化标记物P．选择素以及血小板计数（PLT）、平均血小板体积（MPV）用于溃疡性结肠炎（UC）疾病活动度评估的价值。方法：纳入65例活动期UC患者、31例缓解期UC患者和60例健康对照者。流式细胞术测定外周血P-选择素阳性率,血细胞分析仪测定PLT、MPV,分析三者与UC活动度的相关性。结果：UC患者外周血CD62P阳性率、PLT显著高于对照组（P〈0．01）,MPV显著低于对照组（P〈0．01）;活动期UC患者三项指标的变化均较缓解期UC患者更为显著,组间差异有统计学意义（P〈0．05）。外周血CD62P、PLT与UC活动度呈正相关（P〈0．05）,MPV与UC活动度呈负相关（P〈0．05）。结论：UC患者的机体处于高凝状态。P-选择素、PLT、MPV能反映UC疾病活动度,对病情评估和治疗方案的制定有一定参考价值。     

血小板活化因子及血小板参数在类风湿关节炎中的表达及意义

取32例类风湿关节炎（RA）活动期患者（观察组）静脉血,采用双抗体夹心ELISA法、血球计数仪测定血清血小板活化因子（PAF）及血小板参数[血小板计数（PLT）、血小板平均容积（MPV）、血小板体积分布宽度（PDW）],并与20例健康人（对照组）比较。结果观察组PAF、PLT明显高于对照组（P〈0．01）,MPV、PDW明显低于对照组（P〈0．01）。认为检测血清PAF及血小板参数有助于RA病情评估及预后判断。     

老年急性冠脉综合征与血小板P-选择素表达率的相关性研究

目的探讨血小板P-选择素表达率在老年急性冠脉综合征（ACS）患者中的变化以及血小板P．选择素与冠状动脉狭窄程度的相关性。方法应用流式细胞仪对经冠状动脉造影确诊的51例老年ACS患者、33例稳定型心绞痛（SAP）患者和34例老年正常对照者的血小板P-选择素表达率进行检测，分析血小板P-选择素表达率与老年冠心病的稳定性、狭窄程度的关系。结果老年急性冠脉综合征患者P-选择索的表达率明显高于对照组和稳定性心绞痛组（P〈0．05），而SAP组和对照组无统计学差异。老年冠心病患者冠脉狭窄程度Gensini评分与血小板膜P-选择素表达率之间无很好的相关性（P〉0．05）。结论P-选择素参与炎症反应和血栓形成，血小板P-选择素表达率可作为老年冠心病患者动脉粥样硬化斑块稳定性的判定指标。     

老年2型糖尿病患者血小板参数变化的临床意义

目的探讨老年2型糖尿病患者血小板参数的变化及意义。方法利用美国雅培公司生产全自动血细胞分析仪（CELL-DYN1800）检测40例2型糖尿病患者和42例健康体检者的血小板4项参数,并对结果进行对比分析。结果与正常对照组比较,老年2型糖尿病患者的血小板计数（PLT）降低;血小板压积（PLT）、平均血小板体积（MPV）及血小板体积分布宽度（PDW）均明显升高．差异有统计学意义（P〈0．05）。结论血小板参数测定可为临床诊断和治疗糖尿病提供实验室依据,临床应重视血细胞的检测分析。     

AECOPD血小板参数变化的临床研究

目的探讨慢性阻塞性肺病急性加重期（AECOPD）血小板参数的变化及其临床意义。方法对80例AECOPD患者进行血小板计数（PLT）、平均血小板体积（MPV）、血小板压积（PCT）、血小板分布宽度（PDW）的检测,并与稳定期及80例正常对照组进行比较。结果与稳定期及对照组比较,AECOPD患者PIT明显降低（P〈0.01）,MPV明显升高（P〈0.01）,血小板压积（PCT）降低（P〈0.05）,PDW明显增加（P〈0.01）。结论血小板参数的检测对慢性阻塞性肺病急性加重期有重要意义,有助于指导临床诊断、治疗及预后评估。     

原发性肝癌患者放疗前后血小板参数变化及意义

目的观察血小板参数在原发性肝癌患者常规放疗前后的变化,并探讨其临床意义。方法采用全自动血液分析仪检测70例原发性肝癌患者（肝癌组）放疗前后PLT、平均血小板体积（MPV）、血小板分布宽度（PDW）、大血小板比率（P-LCR）和血小板压积（PCT）,观察并比较血小板参数在肝癌患者放疗前后的变化。另选36例健康体检者作对照（对照组）。结果肝癌组PLT、MPV、PCT、P-LCR均较对照组高（P均〈0．05）,而PDW差异无统计学意义（P〉0.05）。放疗后PLT、MPV、PCT较放疗前明显下降（P〈0．05）,P-LCR、PDW无明显变化（P〉0．05）。结论肝癌患者放疗后PLT、MPV、PCT下降明显。检测血小板参数有助了解肝癌放疗患者的骨髓造血情况。     

急性脑血管病患者血小板变化及临床意义

目的探讨急性脑血管病患者血小板（PLT）参数变化及其临床意义。方法检测156例脑梗死（大面积脑梗死49例,其他脑梗死107例）和109例高血压性脑出血患者急性期、恢复期的PLT计数、血小板平均体积（MPV）及血小板体积分布宽度（PDW）,并与112例健康者（对照组）进行比较。结果与对照组比较,脑血管病患者急性期PLT显著降低,MPV、PDW显著增大（P均〈0.01）,恢复期MPV、PDW仍显著增大（P〈0.01）;与其他脑梗死者比较,大面积脑梗死者MPV、PDW显著增大（P〈0.01）;脑出血和脑梗死患者急性期、恢复期PLT、MPV、PDW比较均无统计学差异（P均〉0.05）。结论脑血管病急性期PLT减少与其大量消耗有关,MPV、PDW增大提示脑血管病变程度严重,必须立即进行干预。     

2型糖尿病患者血小板参数的检测及初步分析

目的通过对2型糖尿病患者的血液参数[血小板计数（PLT）、平均血小板体积（MPV）、血小板体积分布宽度（PDW）、大血小板比率（P-LCR）、血小板压积（PCT）]的调查分析，探讨糖尿病患者血小板参数变化与糖尿病的关系，以及糖尿病患者血小板变化的临床意义。方法选择2000～2006年我部30例2型糖尿病患者作为试验组。选50例年龄为50～72岁的老年人，排除有血液性疾病及其他代谢性疾病者作为对照组，分别采血3次，测血小板参数，包括血小板数（PLT）平均血小板体积（MPV）、血小板体积分布宽度（PDW）、血小板压积（PCT）、大血小板比率（P-LCR）。对所得结果行）χ^2检验。结果试验组与对照组比较，血小板参数变化差异有显著性（P〈0．05）。结论血小板参数变化在糖尿病的病程中对血管病变的发生、发展有重要作用，对临床研究糖尿病有较大参考价值。     

健康体检者血小板参数、P-选择素、PAC-1测定及与年龄的相关性分析

目的 探讨增龄对血小板参数及其活化指标的影响和意义.方法 选择同期行健康体检者400例,其中年龄25～44岁156例（成年组）、45～59岁144例（老年前组）、〉60岁（老年组）100例,均用全自动细胞分析仪测定血小板参数包括血小板计数（PLT）、平均血小板体积（MPV）、血小板体积分布宽度（PDW）和血小板压积（PCT）水平,三组各随机选择30例采用流式细胞仪检测P-选择素（CD62P）及血小板膜糖蛋白Ⅱb/Ⅲa（PAC-1）水平,对年龄与上述指标间相关性行Pearson相关分析.结果 随年龄增加PLT、PCT、PDW下降,MPV增大,CD62P、PAC-1增多;PLT与年龄呈明显负相关,MPV、PAC-1、CD62P与年龄呈明显正相关.结论 血小板参数及其活化指标均与年龄有明显相关性,此为血栓性疾病的预防及诊治提供了理论依据.     

The Platelet Count and Mean Platelet Volume

S ummary. The Coulter Model S-Plus Counter provides a measure of the platelet count and the mean platelet volume (MPV). An analysis of 5000 unselected blood specimens showed an inverse relationship between the number of circulating platelets and their MPV. In nearly 95% of normal adults the platelet count varied from 150 to 450 × 10⁹/1 and the MPV from 7·0 to 10·5 fl. Thrombocytosis was found in iron deficiency anaemia, after trauma and acute blood loss and in rheumatoid arthritis. Although there is a normal platelet distribution in pregnancy, patients with pre-eclampsia and uncomplicated hypertension in late pregnancy tended to have lower platelet counts and larger platelets than controls. A variable platelet pattern was found in infection, renal failure and treated malignant disease.     

Platelet Economy (Platelet Survival and Turnover)*

Investigators studying blood platelet survival and turnover have used the term ‘thrombo-kinetics’ to describe the subject, by analogy with the usages of thermodynamics. Inasmuch as these phenomena reflect the interactions and hazards which the platelets encounter while discharging their function in the circulation, we prefer the term ‘platelet economy’ and we consider that the function and fate of the platelet cannot usefully be separated as objects of study. A number of beliefs about platelet function and economy are widely held. First, the platelets play a leading role in haemostasis, a function which is discharged mainly when injury to the vessel wall occurs; their second main function is considered to be in coagulation, which they support or may even initiate. Beyond these, the platelets are thought to have little useful function. The platelet in vivo is commonly supposed to be a fragile structure, irreversibly damaged by aggregation. Some consider it to have a finite life span, determined by exhaustion of its inner reserves, while others consider its life span to be determined by the demands of the body without regard to the age of the individual platelet. We shall present evidence suggesting that some of these views are gross over-simplifications and some are erroneous.     

Platelet Heterogeneity

Human platelets were separated into 2 density populations by repeated centrifugations of platelet-rich plasma at increasing gravitational force. The heaviest platelet fraction was rich in larger platelets. The lightest platelet fraction was rich in smaller platelets. In both fractions and in the platelet button, lipid peroxidation (malonaldehyde-MDA-production after addition of thrombin) was measured at basal condition, on the 1st, 3rd, 5th, 7th and 9th day after aspirin ingestion. At basal conditions and after ingestion of aspirin, MDA production was higher in the heavy-large platelets than in light-small ones, but a parallel increase of MDA production was observed in the light and in the heavy population and in the platelet button. The data are not compatible with the hypothesis that platelet density and size are age-related. Aspirin inhibits platelet lipid peroxidation by permanently acetylating their cyclooxygenase and if the heaviest platelets were the young ones, lipid peroxidation should reappear sooner in them.     

Platelet Satellitism

Platelet adherence to polymorphonuclearleukocytes, or so-called platelet satellitism, has, to our knowledge, been reportedin only four patients. We had the opportunity to study this phenomenon in twopatients. Platelet satellitism was onlyseen in EDTA anticoagulated blood, andthe platelets were seen to surround polymorphonuclear leukocytes only. Electronmicroscopic studies demonstrated focallyopposed regions of platelet and neutrophilplasma membranes. Phagocytosis ofplatelets was also observed. In vivo andin vitro platelet functions were normal.Platelet satellitism is an in vitro phenomenon, the cause of which is unknown. Weare unable to relate it to functional abnormalitles of the blood, the clinical condition of the patient, or to drugs. Thisphenomenon has some clinical importancein that it causes spurious thrombocytopenia.

Submitted on September 18, 1973 Revised on November 12, 1973 Accepted on November 24, 1973     

Platelet Concentrates

To determine what effect different preparative protocols and different platelet storage bags have on in vitro release, platelet concentrates were prepared according to two different protocols (group I: 2,200 g for 3.5 min followed by 4,900 g for 5 min; group II: 1,000 g for 9 min and 3,000 g for 20 min). The storage bags used were either a standard polyvinyl chloride (PL-146) or a polyolefin bag (PL-732). The results for platelet concentrates stored in PL-146 showed that while group I had undergone more alpha granule release at 24 and 48 h of storage than had group II, by 72 h both groups showed a similar degree of release. Results for platelets stored in PL-732, however, did not show any significant difference in release between the two protocol groups at any storage time up to 120 h. We conclude that although the preparative protocol used may induce different degrees of platelet release in vitro, the platelet storage bag also has a significant influence on the degree of in vitro damage which occurs during subsequent storage.     

Platelet adhesiveness

The method described by Helen Wright for estimation of the adhesiveness ofplatelets has been found to be reproducible. Adhesiveness of platelets is reduced inthe presence of hypocoagulable blood. It may or may not be enhanced when theblood is hypercoagulable. In hemophilia, the adhesiveness of platelets has beenfound to become increased beyond the premedication level when the coagulationdefect is corrected by Fraction 1 derived from human plasma. Two cases exhibitingbleeding are described in which deficient adhesiveness of the thrombocytes was theonly demonstrable defect noted in the coagulation mechanism.

     

Platelet transfusions

Ever since platelet transfusions were shown to reduce mortality from haemorrhage in patients with acute leukaemia in the 1950s, the use of this therapy has steadily grown to become an essential part of the treatment of cancer, haematological malignancies, marrow failure, and haematopoietic stem cell transplantation. Today, more than 1.5 million platelet products are transfused in the USA each year, 2.9 million products in Europe. However, platelet transfusion can transmit infections and trigger serious immune reactions and they can be rendered ineffective by alloimmunisation. There are several types of platelet components and all can be modified to reduce the chances of many of the complications of platelet transfusion. Transfusion practices, including indications for transfusion, dose of platelets transfused, and methods of treating alloimmunised recipients vary between countries, and even within countries. We review commonly used platelet components, product modifications, transfusion practices, and adverse consequences of platelet transfusions.