血液流变学临床检测红细胞聚集性指标的规范化

研究血液流变学临床检测报告单中红细胞聚集性指标的规范化问题.对血沉法和粘度法定义的红细胞聚集性的各种指标进行对比分析,提出设计临床血液流变学指标检测报告单的原则和指标的设定应坚持唯一性原则,即一种流变性只设定一个指标.     

临床血液流变学指标检测报告单设计不合理应该修正

笔者发现虽然血液流变学广泛用于l临床已经20几年，但其指标检测报告单的指标设置仍然比较混乱。报告单设计不合理的现象普遍存在。笔者为了纠正这种现象而撰写此文。研究指出了哪些是科学合理必须的指标和设置这些指标的两方面依据。论文阐明了全血高剪变率、中剪变率、低剪变率黏度，红细胞变形性、聚集性指标的正确含义，并将若干指标的优劣性进行了分析、比较。笔者为血液流变学首次提出了红细胞变形率、红细胞聚集率这两个新概念。研究揭示报告单指标设置不合理性归纳为三个方面：指标太多，指标重复，指标无意义。产生这些不合理性的缘由是：检测仪器厂商炫耀其仪器功能齐全，利于销售；设计者和检验人员血液流变学知识浅薄，指标良莠不分。但愿此文能引起人们重视，共同促进临床血液流变学指标设置和检测规范化。     

丹参对应激大鼠血液流变性的影响

目的：探讨丹参对应激大鼠血液流变性的影响。方法：采用血液粘度计检测血液流变学指标，荧光法检测血浆去甲肾上腺素的含量。结果：束缚应激大鼠血浆去甲状腺素的含量增高，全血比粘度、血浆比粘度、红细胞变形指数、聚集指数、压积、血浆纤维蛋白原含量均增高。经相关分析，去甲肾上腺素含量与血液流变学各指标呈中高度相关。胃灌丹参后，上述各指标均显著下降。结论：丹参能明显改善应激大鼠的血液流变性，可能是通过减少去甲肾上腺素的含量。     

急性脑缺血时血液流变性改变的实验观察

目的探讨急性脑缺血时血液流变学的变化,为临床治疗急性脑缺血提供实验依据。方法采用ＳＤ大鼠,雌雄兼用,麻醉后结扎颈总动脉,建立急性脑缺血实验模型。动物按实验要求随机分为三组：空白对照组、实验观察组和药物治疗组。脑缺血成功后同时抽血,用锥板粘度计测定血流变学有关指标,并比较各组间差异。结果急性脑缺血大鼠的血液流变学出现明显障碍。表现为低切全血粘度明显增高．血浆粘度增高、且红细胞压积亦有增高表现,但与空白对照组间无显著差异（Ｐ＞０．０５）。红细胞聚集指数增高,血沉加快。血液流变学指标显示红细胞聚集性增强,虽高粘滞综合征表现。结论急性脑缺血可引起血液流变性的紊乱,导致红细胞聚集性增高,提示临床治疗时应注意调整红细胞的聚集性和血液的高粘状况,改善微循环和脑组织灌流。     

甘露聚糖肽对心脑血管疾病及肺癌患者血液流变性的影响

目的观察心脑血管疾病及肺癌患者血液流变性的变化及甘露聚糖肽对血液流变性的影响。方法选择临床确诊的病例,分别对30例心脑血管疾病患者及30例肺癌患者用甘露聚糖肽前后的血液流变学指标进行测定。血液流变学检查 :LG -R -80型锥板式血液黏度测试仪 ,检测全血和血浆黏度 ,用WB -A型微量红细胞比积仪 ,转速11000～12000r/min,离心5min,检测红细胞比容 ,用魏氏法检测血沉。结果本组病例检测发现 ,心脑血管疾病及肺癌患者血液流变性存在明显障碍 ,主要表现为全血黏度显著异常 ,从低切变率到高切变率下的表观黏度均增高 ,红细胞聚集性增高 ,血浆黏度增加 ,血液呈高黏滞综合征改变 ,并伴有血小板聚集性增高。表明患者红细胞的聚集性明显增高 ,同时红细胞的变形能力明显降低。甘露聚糖肽对糖尿病患者的全血黏度、血浆黏度、血沉等指标均有明显改善影响 ,用药前后对照有显著差异 (P<0.01或P<0.05) ,其中尤以低切黏度改变最为明显。结论心脑血管疾病和肺癌患者存在血流变性的显著障碍 ,甘露聚糖肽对患者的血流变性有明显改善作用。全血黏度明显改善 ,红细胞聚集性降低 ,变形能力增强等 ,这可能与甘露聚糖肽调整红细胞膜电荷 ,改善红细胞聚集性、变形性有关。     

不同性质脑卒中急性期血液流变性的对比研究

对６５例脑梗塞、４６例脑出血急性期经头颅ＣＴ证实的住院病人进行了全血粘度、红细胞压积、血小板和白细胞计数四项流变学指标检测，并与４０例正常对照组进行了比较。结果：脑出血组三项指标明显高于对照组和脑梗塞组，血小板计数明显低于对照组（Ｐ＜００５）；而脑梗塞有一项指标明显高于对照组。提示血液流变性异常并非仅见于缺血性脑血管病患者，而出血性脑血管病患者同样存在血液流变性异常。故血液流变学指标对缺血性和出血性脑血管病无鉴别价值，可认为是二者发病的共同危险因素之一。     

肺结核患者血液流变学指标的观察

３１例肺结核病患者的血液流变学指标检测结果显示８７．１％（２７例）的患者同时伴有高粘滞血症，其血液流变性有异常变化，特别是全血粘度、血浆粘度、红细胞聚集性、红细胞变形性和血液屈服应力等结果均有显著改变（Ｐ＜０．０１。提示：在肺结核病的诊疗中，及时检测患者的血液流变性，对该病的诊治、病情观察、验证药效及预后等均有重要意义。     

896例脑血栓患者血液流变性分析

检测８９６例脑血栓患者血液流变性九项指标，结果发现其均明显高于８０８例对照组（Ｐ＜０．０５或＜０．０１）。以红细胞流变性改变为基础，分为正常型、全高型、高粘型、高聚型及高压积型。血液流变性的异常是脑血栓发病的重要因素。粘度越高，脑血流量越低；压积越高，粘度越大；ＲＢＣ表面电荷越少，聚集性越强。提示：血液流变学检测的意义在于阐明发病机理、指导临床治疗、帮助患者康复。     

环境温度对大鼠血液流变特性的影响

目的研究在不同环境温度对大鼠的血液流变学指标的影响。方法将7组大鼠(每组10只)分别在温度为7、12、16、22、28、32、35℃环境下饲养7 d后,用心脏穿刺法采集大鼠血液5 mL,肝素抗凝,血液采集完毕后2 h内检测血液流变学各项指标。结果环境温度在7、12、32、35℃时,血液流变学指标异常,红细胞可变性降低,毛细血管阻力增高,红细胞易聚集,从而引起机体血液循环障碍,使局部血流缓慢,造成缺血缺氧,影响组织的代谢和功能。结论血液流变性指标值在16～28℃的温度范围内最佳,血流的阻力小,红细胞的流变性好。机体保持良好微循环的最低环境温度7℃,最高环境温度32℃。     

广州145例军校学员血液流变指标的测定与分析

作者用锥板式粘度计等国内外通用仪器和方法，对广州１４５名健康人进行了血液流变性检测，获得了男女全血粘度、血浆粘度、红细胞压积等１３项血液流变学参数，经异性差异显著性检验及与相关资料比较分析，结果表明这些血液流变学参数基本合理可靠，可作为正常值的参考之用。     

血液流变学研究进展与问题

本文根据大量资料归纳整理，扼要介绍我国临床血液流变学发展现状，基本研究方法，总体成就，红细胞、血浆流变性异常和高粘滞综合症的分子流变学基础及存在问题。     

烧伤后增殖性瘢痕硬度测量的研究

目的：临床评估增殖性瘢痕硬度需要定量测量。本实验研究了两种瘢痕硬度测量方法，通过定标后，瘢痕硬度测量值实现标准化。材料与方法：研制高灵敏度压力传感器和瘢痕硬度测量仪，定标后开展临床测试。结果：测量仪定标后得到硬度转换关系，可标准化。结论：测量结果表明，测量仪灵敏度高、重复性好，对瘢痕无创伤，使用方便，经鉴定后可供临床使用。     

A new framework for the interpretation of IgE sensitization tests

IgE sensitization tests, such as skin prick testing and serum‐specific IgE, have been used to diagnose IgE‐mediated clinical allergy for many years. Their prime drawback is that they detect sensitization which is only loosely related to clinical allergy. Many patients therefore require provocation tests to make a definitive diagnosis; these are often expensive and potentially associated with severe reactions. The likelihood of clinical allergy can be semi‐quantified from an IgE sensitization test results. This relationship varies though according to the patients’ age, ethnicity, nature of the putative allergic reaction and coexisting clinical diseases such as eczema. The likelihood of clinical allergy can be more precisely estimated from an IgE sensitization test result, by taking into account the patient's presenting features (pretest probability). The presence of each of these patient‐specific factors may mean that a patient is more or less likely to have clinical allergy with a given test result (post‐test probability). We present two approaches to include pretest probabilities in the interpretation of results. These approaches are currently limited by a lack of data to allow us to derive pretest probabilities for diverse setting, regions and allergens. Also, cofactors, such as exercise, may be necessary for exposure to an allergen to result in an allergic reaction in specific IgE‐positive patients. The diagnosis of IgE‐mediated allergy is now being aided by the introduction of allergen component testing which may identify clinically relevant sensitization. Other approaches are in development with basophil activation testing being closest to clinical application.     

偏头痛患者血液微循环特征探讨

目的 探讨偏头痛患者的血液微循环特征。方法 观察50例偏头痛患者的红细胞流变性、血液流变性及甲襞微循环变化，并与50例健康人作对照。结果 偏头痛患者红细胞流变性异常，表现为红细胞聚集性增高、红细胞变形性降低；血液黏度增高，呈高黏高凝状态；甲襞微循环异常，主要表现为流态异常、襻顶瘀血、异型管襻数量增多、红细胞聚集、管襻长度缩短、开放管襻数量减少、襻周渗出等。结论 红细胞流变性异常、血液呈高黏高凝状态、微循环障碍是偏头痛患者的血液微循环特征。偏头痛患者血液微循环的异常改变可能是偏头痛的病因之一。     

Sequence variant classification and reporting: recommendations for improving the interpretation of cancer susceptibility genetic test results

Genetic testing of cancer susceptibility genes is now widely applied in clinical practice to predict risk of developing cancer. In general, sequence-based testing of germline DNA is used to determine whether an individual carries a change that is clearly likely to disrupt normal gene function. Genetic testing may detect changes that are clearly pathogenic, clearly neutral, or variants of unclear clinical significance. Such variants present a considerable challenge to the diagnostic laboratory and the receiving clinician in terms of interpretation and clear presentation of the implications of the result to the patient. There does not appear to be a consistent approach to interpreting and reporting the clinical significance of variants either among genes or among laboratories. The potential for confusion among clinicians and patients is considerable and misinterpretation may lead to inappropriate clinical consequences. In this article we review the current state of sequence-based genetic testing, describe other standardized reporting systems used in oncology, and propose a standardized classification system for application to sequence-based results for cancer predisposition genes. We suggest a system of five classes of variants based on the degree of likelihood of pathogenicity. Each class is associated with specific recommendations for clinical management of at-risk relatives that will depend on the syndrome. We propose that panels of experts on each cancer predisposition syndrome facilitate the classification scheme and designate appropriate surveillance and cancer management guidelines. The international adoption of a standardized reporting system should improve the clinical utility of sequence-based genetic tests to predict cancer risk.     

Optimal skin prick wheal size for diagnosis of cat allergy.

BACKGROUND: The skin prick test is the diagnostic procedure of choice for determination of immediate hypersensitivity. A wheal diameter of 3 mm or larger is generally accepted as the cutoff for a positive test result, although the validity of this assumption has not been rigorously demonstrated. OBJECTIVE: To determine the skin prick wheal size that best identifies clinical allergy to cat. METHODS: Forty-five patients referred for evaluation of rhinoconjunctivitis underwent determination of atopic status by skin testing using the Greer Dermapik device and a combination of other modalities, including history, in vitro determination of specific IgE level, and nasal challenge with standardized cat pelt extract. Parameters evaluated before and after nasal challenge included symptom score and nasal lavage tryptase and prostaglandin D (PGD2) levels. RESULTS: The widely accepted 3-mm wheal for a positive skin test result to cat is highly sensitive but only moderately specific for diagnosis of cat allergy as evaluated by history, specific IgE level, postchallenge symptom score, and tryptase and PGD2 levels. Optimal cutoffs for a positive skin test result to cat based on receiver operating characteristic analysis and 95% positive predictive value were 5.5 mm or greater for each of these parameters. When a true-positive result for cat allergy was defined as a combination of positive history, specific IgE level, postchallenge symptom score, and tryptase and PGD2 levels and a true-negative result as all of these parameters being negative, a 6-mm cutoff was able to distinguish cat allergic from cat nonallergic individuals. CONCLUSION: In a potentially allergic population undergoing skin prick testing with the Greer Dermapik using standardized extracts, a 3-mm skin prick wheal will overestimate the presence of cat allergy. A 6-mm wheal appears to distinguish those individuals who are cat allergic from those who are not.     

The medicalization of menopause: implications for recruitment of study participants

OBJECTIVE: Early studies of menopause recruited sample populations from clinical settings; however, in the 1970s, populations drawn from health care settings were characterized as nonrepresentative because of symptom overreporting. This pilot study was carried out to test whether this characterization still holds true: that women who are drawn from clinical settings report more symptoms compared with women who are recruited from community and work sites. DESIGN: Open-ended interviews were carried out with patients aged 40-60 years in a physician's office (n = 50), in a chiropractor's office (n = 24), at two Breast Health Project sites (n = 50), and in several non-health care sites in the community (n = 81). Interviews were supplemented by anthropometrics and standardized return-by-mail questionnaires. RESULTS: Women who experienced hot flashes and sweating were more likely to report having spoken with a physician about menopause. However, women who were drawn from the clinical setting were not significantly more likely to describe hot flashes, sweats, or mood changes and were significantly less likely to report headaches in relation to menopause compared with a community sample. Women who were drawn from the physician's office were more likely to use hormone replacement therapy and to have had a hysterectomy. CONCLUSIONS: This study suggests that because of the medicalization of menopause, we need to rethink our assumptions about the characteristics of populations drawn from health care settings. In western Massachusetts, place of recruitment did not predict symptom frequency.     

Psychosocial and educational outcomes associated with home- and clinic-based pretest education and cystic fibrosis carrier testing among a population of at-risk relatives

We report on the psychosocial and knowledge outcomes of two different approaches to cystic fibrosis (CF) gene pretest education and carrier testing offered to 288 proactively recruited first-, second-, and third-degree relatives of people with CF. One group received pretest education and gene testing in a clinical setting from a certified genetic counselor. The other group received pretest education in their homes from a specially prepared pamphlet and were asked to send in a buccal cell sample for genotyping. No statistically significant differences between groups were noted on measures of CF knowledge, anxiety, and positive or negative affect, either while waiting for their test results or within a few weeks after they had learned their results. At both measurement points, participants who had received home education and testing reported that the testing was more convenient, but that they had received less information than they would have liked, and they were more likely to report being confused by the testing, although their level of CF knowledge was comparable to that of people who had been seen by a genetic counselor. In light of the increasing interest in home-based medical testing of all kinds, this study suggests that CF carrier testing in the home warrants further consideration as one possible approach to facilitating access to testing. Am. J. Med. Genet. 75:461–468, 1998. © 1998 Wiley-Liss, Inc.