海藻硫酸多糖抗氧化与抗肿瘤作用的实验研究

目的：观察海藻硫酸多糖（ＳＰ）对正常及荷瘤小鼠肝匀浆及红细胞中ＳＯＤ，ＧＳＨ－Ｐｘ活性及脂质过氧化产物ＭＤＡ含量的影响，探讨其抗氧化与抗肿瘤之间的关系。结果：移植肿瘤Ｓ１８０使肝组织中ＳＯＤ，ＧＳＨ－Ｐｘ活性分别由１１３．７３±８．１７降至７１．４１±１０．９８ｍｇ／Ｌ（Ｐ＜０．０５），３２．３４±０．０５降至２９．９６±０．１６Ｕ（Ｐ＜０．０１），ＭＤＡ含量由０．２３４±０．００１增至０．２８０±０．０１２（Ｐ＜０．０５），腹腔注射或口服ＳＰ则使ＳＯＤ，ＧＳＨ－Ｐｘ活性增至１１８．７７±１８．９２ｍｇ／Ｌ（Ｐ＜０．０５），３６．５８±１．０６Ｕ（Ｐ＜０．０１），ＭＤＡ含量降至０．１０４±０．０３９（Ｐ＜０．０１）。且腹腔注射ＳＰ１００ｍｇｋｇ－１ｄ－１×１０ｄ可使肿瘤抑制率达３９．１３％，口服ＳＰ２００ｍｇｋｇ－１ｄ－１×１０ｄ也能使肿瘤抑制率达２８．０４％。结论：ＳＰ抑瘤作用的机理可能与抗氧化有关。     

吸烟与动脉硬化性脑梗塞关系的研究

目的：探讨吸烟与动脉硬化性脑硬塞（ＡＳＣＩ）的关系。方法：对１０２例ＡＳＣＩ患者及１０８例正常人血清载脂蛋白（Ａｐｏ－Ｂ）、高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）、总胆固醇（ＴＣ）进行测定及对比分析。结果：ＡＳＣＩ组Ａｐｏ－Ｂ比对照组显著升高（Ｐ＜０．０１）,ＨＤＬ－Ｃ比对照组显著降低（Ｐ＜０．０１）,而ＴＣ两组间无明显差异（Ｐ＞０．０５）。在对照组及ＡＳ－ＣＩ组吸烟者Ａｐｏ－Ｂ均高于非吸烟者（Ｐ＜０．０１,Ｐ＜０．０５）,而ＨＤＬ－Ｃ吸烟者明显低于非吸烟者（Ｐ＜０．０１）。结论：吸烟能促使血清Ａｐｏ－Ｂ增高及ＨＤＬ－Ｃ下降,可以认为吸烟是ＡＳＣＩ的危险因素之一。     

儿童体操运动员的能量消耗

用双标水方法测定了１２名６～８岁体操运动员（男女各６名）的总能量消耗（ＴＥＥ）。同时用开放式间接测热法检测了他们的基础代谢率（ＢＭＲ）。根据总能量消耗与基础代谢率的比值推算出每日体力活动水平（ＰＡＬ），用ＴＥＥ－（ＢＭＲ＋０．１ＴＥＥ）表示其在体力活动上的能量消耗（ＥＣＰＡ）。结果表明：儿童体操运动员的总能量消耗平均为８．３９±１．０８ＭＪ／ｄ（男：８．６７±１．４２ＭＪ／ｄ；女：８．１１±０．５９ＭＪ／ｄ，Ｐ＞０．０５），分别高于ＷＨＯ和我国推荐的每日能量需要量标准的３６％（Ｐ＜０．００１）和１３％（Ｐ＜０．０１）。基础代谢率平均为４．２２±０．３６ＭＪ／ｄ（男：４．４５±０．３４ＭＪ／ｄ；女：３．９９±０．２１ＭＪ／ｄ，Ｐ＜０．０５）。体力活动水平平均为１．９８±０．２９（男：１．９６±０．３５；女：２．０４±０．１５，Ｐ＞０．０５）；体力活动的能量消耗平均为３．３４±１．００ＭＪ／ｄ（男：３．３５±１．３９ＭＪ／ｄ；女：３．３２±０．５０ＭＪ／ｄ，Ｐ＞０．０５）。儿童体操运动员的总能量消耗高于ＲＤＡ，与其每日从事运动训练时消耗大量能量有关。     

复印作业对人体氧化和过氧化的影响

目的探讨复印作业对人体氧化和过氧化的影响。方法检测１０４例复印作业者和１００例健康成人血浆ＶｉｔＣ、ＶｉｔＥ、β－胡萝卜素（β－ＣＡＲ）、过氧化脂质（ＬＰＯ）含量及红细胞超氧化物歧化酶（ＳＯＤ）、过氧化氢酶（ＣＡＴ）、谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活力和ＬＰＯ含量。结果与健康成人组比较，复印作业组的血浆ＶｉｔＣ、ＶｉｔＥ、β－ＣＡＲ和红细胞ＳＯＤ、ＣＡＴ、ＧＳＨ－Ｐｘ平均值皆显著降低（Ｐ＜０．０１），而血浆及红细胞ＬＰＯ平均值明显升高（Ｐ＜０．０１），３种不同机型复印作业组各指标平均值间皆差异无显著性（Ｐ＞０．０５），配备通风装置组与未配备通风装置组各指标平均值间差异皆有显著性（Ｐ＜０．０１），复印作业工龄与各指标间均呈一定程度的直线相关（Ｐ＜０．０２～０．０００１）。结论复印从业人员体内氧化和过氧化反应加剧     

腺苷脱氨酶对结核性、癌性胸膜炎鉴别诊断的价值

分析４０ 例结核性胸膜炎，１４ 例癌性胸膜炎和８ 例细菌性胸膜炎患者血清和胸水腺苷脱氨酶（ Ａ Ｄ Ａ） 活性。结果显示：结核性胸水 Ａ Ｄ Ａ 活性显著高于细菌性和癌性胸水（ Ｐ＜ ０ ．０１） ；结核性胸水患者 Ａ Ｄ Ａ 胸水／ 血清比值＞ １ ，而细菌性、癌性胸水患者则＜ １ ，两者比较差异有显著性（ Ｐ＜ ０ ．０１） 。提示这二项指标有助于结核性胸膜炎和细菌性、癌性胸膜炎的鉴别诊断。     

高血压伴肥胖和高血压非肥胖患者胰岛β细胞早期分泌相的改变

为了解高血压伴肥胖者（ＯＨＴ）和高血压非肥胖者（ＮＯＨＴ）胰岛β细胞早期分泌相的变化规律，用左旋精氨酸（Ｌ－ＡＲＧ）刺激法，对ＨＴ患者胰岛β细胞分泌功能进行了研究。结果：（１）空腹胰岛素（ＩＮＳ）、Ｃ－肽（Ｃ－Ｐ）值ＯＨＴ组明显高于对照组和ＮＯＨＴ组（Ｐ＜０．０５或Ｐ＜０．０１），后两者间无明显差异（Ｐ＞０．０５）。（２）Ｌ－ＡＲＧ兴奋后ＯＨＴ和ＮＯＨＴ组ＩＮＳ和Ｃ－Ｐ分泌在４分钟时达峰值，而对照组２分钟达峰值。（３）Ｌ－ＡＲＧ兴奋后ＩＮＳ和Ｃ－Ｐ各时点增加值的和（△∑）以ＯＨＴ组明显高于对照组和ＮＯＨＴ组，后两者无显著差异。（４）ＯＨＴ组△∑ＩＮＳ与ＤＢＰ和体重指数（ＢＭＩ）均呈明显正相关（Ｐ＜０．０５），而ＮＯＨＴ组多元回归分析未发现△∑ＩＮＳ与ＤＢＰ和ＢＭＩ有相关性。结果提示ＯＨＴ患者存在胰岛素抵抗（ＩＲ），Ｌ－ＡＲＧ刺激胰岛β细胞早期分泌相是增加的；ＮＯＨＴ患者ＩＲ不明显。ＩＲ是ＯＨＴ发病的原因之一。     

糖尿病患者的血液一氧化氮和氧化及脂质过氧化指标

检测１１４例糖尿病患者和１００例健康人血浆中的一氧化氮（ Ｐ Ｎ Ｏ）、维生素 Ｃ（ Ｐ Ｖ Ｃ）、维生素 Ｅ（ Ｐ Ｖ Ｅ）、β 胡萝卜素（ Ｐ β Ｃ Ａ Ｒ）、过氧化脂质（ Ｐ Ｌ Ｐ Ｏ）含量及红细胞中的超氧化物歧化酶（ Ｅ Ｓ Ｏ Ｄ）、过氧化氢酶（ Ｅ Ｃ Ａ Ｔ）、谷胱甘肽过氧化物酶（ Ｅ Ｇ Ｓ Ｈ Ｐｘ）活性和过氧化脂质（ Ｅ Ｌ Ｐ Ｏ）含量以探讨与糖尿病的关系。结果表明,糖尿病组及Ⅰ型、Ⅱ型糖尿病组的 Ｐ Ｎ Ｏ、 Ｐ Ｌ Ｐ Ｏ、 Ｅ Ｌ Ｐ Ｏ 均显著高于对照组（ Ｐ＜ ００１）, Ｐ Ｖ Ｃ、 Ｐ Ｖ Ｅ、 Ｐ β Ｃ Ａ Ｒ、 Ｅ Ｓ Ｏ Ｄ、 Ｅ Ｃ Ａ Ｔ、 Ｅ Ｇ Ｓ Ｈ Ｐｘ 均显著低于对照组（ Ｐ＜ ００１）;并随着病程的延长而逐渐升高或降低。逐步回归分析结果提示患者病程与 Ｐ Ｎ Ｏ、 Ｐ Ｖ Ｃ、 Ｅ Ｓ Ｏ Ｄ、 Ｅ Ｇ Ｓ Ｈ Ｐｘ、 Ｅ Ｌ Ｐ Ｏ 值密切相关。认为糖尿病患者 Ｎ Ｏ 代谢异常,抗氧化、抗过氧化和抗脂质过氧化作用受损。     

调和油中不同饱和程度脂肪酸配比效应的研究

观察在低胆固醇摄入（８９ｇ基础饲料＋１１ｇ调和油）和高胆固醇摄入（８９ｇ基础饲料＋１１ｇ调和油＋１ｇ胆固醇）两种条件下调和油对大鼠血脂、血清和肝ＭＤＡ、血清和肝ＳＯＤ、膜流动性等指标的影响。结果表明，低胆固醇摄入条件下，１∶１∶１５组血清ＴＣ、ＬＤＬＣ、ＭＤＡ极显著降低（Ｐ＜００１），血清ＳＯＤ活力极显著升高（Ｐ＜００１），膜流动性显著升高（Ｐ＜００５）；１∶１５∶１组血清ＳＯＤ活力、膜流动性显著升高（Ｐ＜００５）；１５∶１∶１组血清ＳＯＤ活力显著升高（Ｐ＜００５）。高胆固醇摄入条件下，１∶１∶１组血清ＴＣ显著降低（Ｐ＜００５）；１∶１∶１５组血清ＬＤＬＣ显著升高（Ｐ＜００５）；１∶１５∶１组和１５∶１∶１组血清ＴＣ和ＬＤＬＣ均极显著升高（Ｐ＜００１）。４个实验组的肝ＳＯＤ活力均极显著降低（Ｐ＜００１）、血清ＳＯＤ活力和膜流动性均极显著升高（Ｐ＜００１）。     

应用ROC曲线分析评价血脂及载脂蛋白对老年冠心病的诊断价值

评价诊断价值的基本指标是灵敏度（Ｓｅ）和特异度（Ｓｐ），ＲＯＣ曲线是以Ｓｅ为纵坐标．（１－Ｓｐ）为横坐标绘成的曲线，曲线下的面积反映试验诊断准确性的大小。通过对２１４例老年冠心病（ＣＨＤ）患者和１７２例健康老年人血清胆固醇（ＴＣ）、甘油三酯（ＴＧ）、载脂蛋白ＡＩ和Ｂ（ＡｐｏＡ、ＡｐｏＢ）水平的观察，结果显示两组间有显著性差异（Ｐ＜０．０５或Ｐ＜０．０１）。应用ＲＯＣ曲线分析，各指标曲线下面积在０．５６～０７２之间，对老年ＣＨＤ辨别力的强弱依次为ＡｐｏＡ＿１／ＡｐｏＢ、ＡｐｏＢ、ＡｐｏＡ＿１、ＴＧ和ＴＣ，提示ＡｐｏＡ＿１／ＡｐｏＢ为最有价值的指标。     

新生儿缺氧缺血性脑病血浆β内啡肽、皮质醇、血糖水平变化及临床意义

目的：为探讨新生儿危重症β内啡肽（β－ＥＰ）、皮质醇（ＣＯＲ）、血糖水平变化及临床意义。方法：用放射免疫法测定６１例新生儿缺氧缺血性脑病（ＨＩＥ）患儿血浆β－ＥＰ、ＣＯＲ及用微量血糖仪检测血糖,并对２２例重症患儿进行动态观察。结果：ＨＩＥ患儿第一天β－ＥＰ、ＣＯＲ水平中重度组高于对照组,重度组高于中与轻度组Ｐ均＜０．０１。重度组治疗３、５天动态观察,β－ＥＰ、ＣＯＲ含量仍高于对照组Ｐ＜０．０１或Ｐ＜０．０５,第七天明显下降与对照组比Ｐ＞０．０５。８例高血糖患儿β－ＥＰ、ＣＯＲ含量高于非高血糖患儿Ｐ＜０．０５,其中５例预后不良。结论：β－ＥＰ、ＣＯＲ、血糖的显著升高,提示严重应激反应,与疾病严重度、转归相平行,三者同步增高往往预后不良     

Diagnostic ambivalence: psychiatric workarounds and the Diagnostic and Statistical Manual of Mental Disorders

In 1980 the American Psychiatric Association (APA), faced with increased professional competition, revised the Diagnostic and Statistical Manual of Mental Disorders (DSM). Psychiatric expertise was redefined along a biomedical model via a standardised nosology. While they were an integral part of capturing professional authority, the revisions demystified psychiatric expertise, leaving psychiatrists vulnerable to infringements upon their autonomy by institutions adopting the DSM literally. This research explores the tensions surrounding standardisation in psychiatry. Drawing on in‐depth interviews with psychiatrists, I explore the ‘sociological ambivalence’ psychiatrists feel towards the DSM, which arises from the tension between the desire for autonomy in practice and the professional goal of legitimacy within the system of mental health professions. To carve a space for autonomy for their practice, psychiatrists develop ‘workarounds’ that undermine the DSM in practice. These workarounds include employing alternative diagnostic typologies, fudging the numbers (or codes) on official paperwork and negotiating diagnoses with patients. In creating opportunities for patient input and resistance to fixed diagnoses, the varied use of the DSM raises fundamental questions for psychiatrists about the role of the biomedical model of mental illness, especially its particular manifestation in the DSM.     

Diagnostic amniocentesis and bacteraemia

Thirty antenatal patients with intact membranes were studied to determine the incidence of bacteraemia induced by transabdominal amniocentesis. No bacteraemias were detected following the procedure. Antibiotic prophylaxis is probably not warranted for immunocompetent hospitalized patients undergoing amniocentesis.     

慢性铅中毒诊断指标与诊断标准的研究

铅中毒诊断标准修订协作组在统一规范、统一质控条件下，进行了全国性的调研工作。调查了非接铅正常人群１５８８人，接铅工人１６００人。得出了有质量保证的各项铅指标的正常参考值及其影响因素与地区差异情况；分析评价了常用铅中毒检验指标的意义及其相关性；用判别分析法求出了“三值”。针对调查分析结果，结合“三值”讨论了标准修改问题。     

Diagnostic Needle Arthroscopy and the Economics of Improved Diagnostic Accuracy: A Cost Analysis

Background

Hundreds of thousands of surgical arthroscopy procedures are performed annually in the United States (US) based on MRI findings. There are situations where these MRI findings are equivocal or indeterminate and because of this clinicians commonly perform the arthroscopy in order not to miss pathology. Recently, a less invasive needle arthroscopy system has been introduced that is commonly performed in the physician office setting and that may help improve the accuracy of diagnostic findings. This in turn may prevent unnecessary follow-on arthroscopy procedures from being performed.

Objective

The purpose of this analysis is to determine whether the in-office diagnostic needle arthroscopy system can provide cost savings by reducing unnecessary follow on arthroscopy procedures.

Methods

Data obtained from a recent trial and from a systematic review were used in comparing the accuracy of MRI and VisionScope needle arthroscopy (VSI) with standard arthroscopy (gold standard). The resultant false positive and false negative findings were then used to evaluate the costs of follow-on procedures. These differences were then modeled for the US patient population diagnosed and treated for meniscal knee pathology (most common disorder) to determine if a technology such as VSI could save the US healthcare system money. Data on surgical arthroscopy procedures in the US for meniscal knee pathology were used (calendar year [CY] 2010). The costs of performing diagnostic and surgical arthroscopy procedures (using CY 2013 Medicare reimbursement amounts), costs associated with false negative findings, and the costs for treating associated complications arising from diagnostic and therapeutic arthroscopy procedures were assessed.

Results

In patients presenting with medial meniscal pathology (International Classification of Diseases, 9th edition, Clinical Modification [ICD9CM] diagnosis 836.0), VSI in place of MRI (standard of care) resulted in a net cost savings to the US system of US$115–US$177 million (CY 2013) (use of systematic review and study data, respectively). In patients presenting with lateral meniscus pathology (ICD9CM 836.1), VSI in place of MRI cost the healthcare system an additional US$14–US$97 million (CY 2013). Overall aggregate savings for meniscal (lateral plus medial) pathology were identified in representative care models along with more appropriate care as fewer patients were exposed to higher risk surgical procedures.

Conclusions

Since in-office arthroscopy is significantly more accurate, patients can be treated more appropriately and the US healthcare system can save money, most especially in medial meniscal pathology.     

Diagnostic error and clinical reasoning

Context There is a growing literature on diagnostic errors. The consensus of this literature is that most errors are cognitive and result from the application of one or more cognitive biases. Such biased reasoning is usually associated with ‘System 1’ (non‐analytic, pattern recognition) thinking. Methods We review this literature and bring in evidence from two other fields: research on clinical reasoning, and research in psychology on ‘dual‐process’ models of thinking. We then synthesise the evidence from these fields exploring possible causes of error and potential solutions. Results We identify that, in fact, there is very little evidence to associate diagnostic errors with System 1 (non‐analytical) reasoning. By contrast, studies of dual processing show that experts are as likely to commit errors when they are attempting to be systematic and analytical. We then examine the effectiveness of various approaches to reducing errors. We point out that educational strategies aimed at explaining cognitive biases are unlikely to succeed because of limited transfer. Conversely, there is an accumulation of evidence that interventions directed at specifically encouraging both analytical and non‐analytical reasoning have been shown to result in small, but consistent, improvements in accuracy. Conclusions Diagnostic errors are not simply a consequence of cognitive biases or over‐reliance on one kind of thinking. They result from multiple causes and are associated with both analytical and non‐analytical reasoning. Limited evidence suggests that strategies directed at encouraging both kinds of reasoning will lead to limited gains in accuracy. Medical Education 2010: 44 : 94–100