积雪草总苷元抗抑郁作用机制的初步研究

目的探讨积雪草总苷元的抗抑郁作用机制。方法采用育亨宾毒性增强实验、阿朴吗啡致刻板运动实验、5-羟色胺酸诱导甩头实验、单胺氧化酶抑制实验等多种动物模型探讨积雪草总苷元抗抑郁作用的可能机制。结果积雪草总苷元不协同育亨宾和阿朴吗啡对小鼠的作用,但显著增加5-羟色氨酸致小鼠甩头作用和盐酸色胺致癫痫样作用。结论积雪草总苷元抗抑郁作用可能与其增加5-羟色胺能神经系统、抑制单胺氧化酶（MAO）有关。     

5-HT_（1A）受体激动和5-HT重摄取抑制双靶标新药YL-0919抗抑郁作用的药效学评价

目的评价兼有5-HT1A受体激动和5-HT重摄取抑制双靶标化合物YL-0919的抗抑郁作用,并在靶标水平探讨其作用机制。方法和结果在小鼠悬尾和小鼠强迫游泳实验中,YL-0919（1.25,2.5,5 mg/kg,ig）能够显著地缩短小鼠悬尾不动时间和游泳不动时间,5-HT1A受体拮抗剂WAY100635（0.3 mg/kg,sc）能够完全拮抗YL-0919（2.5 mg/kg,ig）在小鼠悬尾实验中的抗抑郁作用;在药物诱发抑郁模型上,YL-0919增强5-羟色氨酸（5-hydroxytryptophan,5-HTP,120 mg/kg,ip）诱导的小鼠甩头行为,但不能拮抗高剂量阿扑吗啡（16 mg/kg,sc）诱导的降温作用;YL-0919在抗抑郁有效剂量范围内对小鼠的自主活动性无显著性影响。结论新型双靶标新药YL-0919具有明确的抗抑郁作用,此作用与激动5-HT1A受体,增强5-HT系统的功能有关。     

胍丁胺在药物诱发抑郁模型上的药效评价

目的在药物诱发抑郁模型上观察胍丁胺(Agmatine,AG)的抗抑郁作用及可能的作用机制。方法采用小鼠5羟色胺酸(5hydroxytryptophan,5HTP)增强实验,小鼠育亨宾(yohimbine,YOH)毒性增强实验,小鼠阿朴吗啡(apomorphine,APO)诱导体温下降和利血平(reserpine,RES)诱导体温下降实验探讨AG抗抑郁作用及可能的作用环节。用VIDEOMEXV型图像运动解析仪检测小鼠自发活动行为。结果在小鼠5HTP增强实验模型上,单次ig给予AG10～20mg·kg-1剂量,或多次ig给予AG10～80mg·kg-1(qd,连续3d),对5HTP诱导的小鼠甩头行为均具有显著增强作用。在小鼠YOH毒性增强实验模型上,多次ig给予AG10～160mg·kg-1(qd,连续3d),均未见增强YOH毒性作用。在小鼠APO诱导体温下降实验模型上,ig给予AG10～80mg·kg-1(qd,连续7d),对APO16mg·kg-1诱导的降温和AUC0～30均未见显著性的拮抗作用。在小鼠RES诱导体温下降实验模型上,ig给予AG10～80mg·kg-1(qd,连续7d),对RES1mg·kg-1诱导的降温和AUC0～6均有显著的拮抗作用。小鼠ig给予AG10～80mg·kg-1(qd,连续3d)对自发活动无显著性改变。结论AG在药理学抑郁模型有显著的抗抑郁活性。并且其抗抑郁活性与增强5羟色胺(5HT)神经系统功能有关,而与去甲肾上腺素能(NE)神经功能无关。AG在抗抑郁有效剂量范围内无中枢兴奋或抑制性作用。     

半夏夏枯草合剂抗抑郁作用的药理实验研究

 目的 研究半夏夏枯草合剂的抗抑郁作用.方法 采用小鼠悬尾实验、小鼠强迫游泳实验、利血平诱导小鼠体温下降实验和开场实验研究半夏夏枯草合剂的抗抑郁作用.结果 在小鼠悬尾实验中,半夏夏枯草合剂大剂量组能明显缩短模型小鼠的不动时间;在小鼠强迫游泳实验中,半夏夏枯草合剂大剂量组和中剂量组能明显缩短模型小鼠的不动时间;在利血平诱导的体温下降实验中,半夏夏枯草合剂大剂量组和中剂量组能明显抑制小鼠体温的下降;在开场实验中,各剂量组对小鼠的自主活动均无明显影响.结论 半夏夏枯草合剂有明显的抗抑郁作用.     

天茄子不同提取部位止血作用研究

目的研究天茄子不同提取部位的止血药理作用。方法依次以环己烷（T1）、水（T2）和乙醇（T3）为溶剂进行提取并对乙醇提取物依次用石油醚（T4）、乙酸乙酯（T5）、正丁醇（T6）进行萃取得到相应的部位以及水部位（T7）,采用毛细玻管法、玻片法、剪尾法和测定血浆复钙时间检测其止血作用。结果 T3、T6、T7可缩短小鼠玻片法凝血时间,T3、T5、T6、T7可显著缩短小鼠毛细管法凝血时间,T3、T4、T5、T6、T7可显著缩短小鼠断尾法出血时间,T3、T6、T7可显著缩短小鼠血浆复钙时间。结论天茄子95%醇总提物、乙酸乙酯部位、正丁醇部位、水部位凝血效果显著,其中95%醇总提物、正丁醇部位、水部位凝血效果极其显著。     

九种滇产药用植物体外抗菌作用及其活性部位的初步研究

目的测定9种滇产药用植物的80%乙醇提取物及石油醚、乙酸乙酯、正丁醇萃取部分体外抗菌活性。方法制备9种药材的80%乙醇浸膏及其石油醚、乙酸乙酯、正丁醇萃取物,对其进行抗菌活性的筛选。通过微量稀释法测定其最低抑菌浓度（MIC）和最低杀菌浓度（MBC）。结果 9种提取物的醇提物及萃取部分中,大叶藤黄和滇南红厚壳的乙酸乙酯部分、粗糠茶的乙醇浸膏及乙酸乙酯部分对标准金黄色葡萄球菌的活性最好,抑菌圈均为19 mm,MIC分别为128、1024、1024、256μg·ml-1;小叶藤黄的乙酸乙酯部分对铜绿假单胞菌活性最好,抑菌圈为20 mm,MIC为2048μg·ml-1;粗糠茶的乙酸乙酯部分对产超广谱β-内酰胺酶肺炎克雷伯菌的活性最好,抑菌圈为17 mm,MIC〉2048μg·ml-1;蓝叶藤的正丁醇部分对标准大肠埃希菌、产超广谱β-内酰胺酶大肠埃希菌、白假丝酵母菌、光滑念珠菌、热带念珠菌、烟曲霉菌的抑菌圈分别为26、28、34、30、15、38 mm,MIC分别为1024、256、512、1024、1024、128μg·ml-1。结论 9种中药中,蓝叶藤的正丁醇部分具有广谱抗菌活性,特别是对烟曲霉菌也有一定的抑制作用。     

巴戟天水提物对慢性应激诱导的大鼠抑郁样行为的改善作用和机制研究

目的 探究巴戟天水提物的抗抑郁效果及作用机制。方法 SD大鼠36只,随机分成空白组、模型组、阳性药盐酸氟西汀组、巴戟天水提物低、中、高3个剂量组。采用慢性不可预知性应激方法造模并给药28 d,通过行为学评价巴戟天水提物的抗抑郁效果,苏木精-伊红染色法（HE）观察大鼠海马神经细胞的形态,免疫组化检测核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)炎症小体和小胶质细胞活化标志物离子化钙结合适配分子1(Iba-1)的表达水平,Western印迹检测脑源性神经营养因子（BDNF）、磷脂酰肌醇3-激酶（PI3K）、蛋白激酶B(Akt)、糖原合酶激酶3β(GSK3β)蛋白表达水平。结果 给药组较模型组糖水偏好率明显增加（P<0.01）,强迫游泳的不动时间显著缩短（P<0.05）;大鼠海马CA3区神经元形态有所改善;NLRP3炎症小体和小胶质细胞Iba-1蛋白表达减少;BDNF、PI3K及其磷酸化（p-PI3K）蛋白、Akt及其磷酸化（p-Akt）蛋白表达增加,GSK3β及其磷酸化（p-GSK3β）蛋白表达减少。结论 巴戟天水提物可改善慢性刺激诱导的大鼠抑郁样行为,其作用机制可能是通过改...     

枳椇子提取物对大鼠抗疲劳作用的比较

目的研究枳椇子乙酸乙酯萃取物对跑台运动大鼠的抗疲劳作用,并比较枳椇子乙酸乙酯萃取物和枳椇子水提醇沉提取物的抗疲劳作用。方法除正常组外,所有实验动物每天进行30 min速度为15 m/min的跑台训练,连续7 d;同时分别灌胃给予枳椇子乙酸乙酯萃取物水混悬液4、8、12 mg/(kg.d);枳椇子水提醇沉提取物水混悬液300 mg/(kg.d);诺迪康胶囊280 mg/(kg.d)(阳性药物组);模型组与对照组分别灌胃给予等体积饮用水(10 ml/kg),连续7 d;于第8天进行1 h速度为25 m/min的跑台运动;跑台结束后,立即采集血液、肝脏、肌肉和脑组织,检测血清肌酸激酶、血清乳酸脱氢酶、血清乳酸、血清乙酰胆碱酯酶、血清尿素氮、血清总抗氧化力、血糖、血红蛋白、脑超氧化物歧化酶、脑丙二醛、肝糖原、肌糖原等指标。结果模型组与对照组比较,各检测指标有显著性差异;枳椇子乙酸乙酯萃取物给药组大鼠的各项指标得到明显改善,中、高剂量组各项指标改善状况优于枳椇子水提醇沉组。结论枳椇子乙酸乙酯萃取物对跑台运动大鼠具有显著的抗疲劳作用,并优于枳椇子水提醇沉物。     

元宝草以RXRα为靶点诱导肺癌细胞凋亡

 目的 利用维甲酸受体(RXRα)为分子平台,从大量中草药提取物库中筛选可治疗肺癌的有效治疗药物,并深入研究其作用机制.方法 实验中使用肺癌细胞系H460.利用配体-受体亲和实验以及报告基因系统筛选可作用于RXRα有效组分或化合物,利用免疫荧光检测RXR在细胞内的分布,用MTT法检测药物对细胞的生长抑制,用DAPI检测细胞的凋亡情况.结果 发现元宝草中含有可结合RXRα并抑制RXRα转录活性的有效组分,这些组分为元宝草的醇提部位,在其馏分中主要位于氯仿萃取部位,这些有效部位可诱导肺癌细胞H460 RXRα出核,其作用依赖于细胞内RXRα的量,而且元宝草诱导RXRα出核在浓度上与细胞凋亡密切相关. 结论中药元宝草提取物中含有可以直接结合RXRα的有效部位,其作用通过诱导RXRα出核和抑制RXRα转录活性而引起肺癌细胞H460的凋亡,这将为分离和开发这一药物提供重要的依据.     

地骨皮提取物CL-5拮抗内毒素的实验研究

目的 观察地骨皮提取物(CL-5)对内毒素(LPS)的体内外拮抗活性.方法 应用生物传感器技术检测CL-5与LPS的活性中心类脂A(Lipid A)的结合活性,ELISA法检测不同浓度CL-5(50、100、200mg/L)对LPS(100μg/L)刺激RAW264.7细胞释放肿瘤坏死因子-α(TNF-α)的影响,进一步观察不同剂量(30、60、90mg/kg)的CL-5对致死剂量热灭活大肠杆菌(E.coil)攻击小鼠的72小时存活率.结果 10～640mg/L的CL-5,特异性结合值(RU)为36.5～481.2arc/s,随CL-5浓度递增而升高;单纯LPS刺激RAW264.7细胞(对照组)释放的TNF-α为(2479.03±61.43)ng/L,给予50、100、200mg/L CL-5预处理后TNF-α浓度依次为(2 210.29±70.95)、(1 998.27±111.24)、(1 423.28±86.35)ng/L,随CL-5剂量递增而减少,均显著低于对照组(P<0.05);以1.30×1011CFU/kg热灭活E.coil攻击小鼠(对照组)72小时动物死亡率为100%,而以30、60、90mg/kg CL-5处理后,小鼠72小时存活率分别为50%、60%和80%,随CL-5注射剂量的增加而升高,均显著高于对照组(P<0.05).结论 CL-5与Lipid A有一定的结合活性,可抑制LPS诱导的RAW264.7细胞活化,并对致死剂量热灭活E.coil攻击的小鼠具有保护作用.     

Safety of regadenoson, an adenosine A2A receptor agonist for myocardial perfusion imaging, in mild asthma and moderate asthma patients: A randomized, double-blind, placebo-controlled trial

Background. Patients with reactive airways are at risk for adenosine-induced bronchocon-striction, mediated via A_2B and/or A₃ adenosine receptors. Methods and Results. To examine the effects of regadenoson, a selective adenosine A_2A receptor agonist, on airway resistance, we conducted a randomized, double-blind, placebo-controlled crossover trial in asthmatic patients with a positive adenosine monophosphate challenge test. The mean ratio of the forced expiratory volume in 1 second (FEV₁) at each tested time point relative to the baseline FEV₁ was significantly higher after treatment with regadenoson compared with placebo from 10 to 60 minutes after treatment. One patient had a substantial but asymptomatic FEV₁ reduction (−36.2%) after regadenoson that reversed spontaneously. The most common adverse events with regadenoson were tachycardia (66%), dizziness (53%), headache (45%), and dyspnea (34%). The mean heart rate significantly increased with regadenoson (maximum of +10.4 beats/min) versus placebo. Conclusions. In this pilot safety study of 48 patients with mild or moderate asthma who had bronchial reactivity to adenosine monophosphate, regadenoson was safe and well tolerated. CV Therapeutics provided financial assistance for this study.     

CLIA、TRUST和TPPA3种梅毒检测方法的比较

目的 通过比较化学发光免疫分析（CLIA）、梅毒螺旋体明胶凝集试验（TPPA）、甲苯胺红不加热血清试验（TRUST）3种梅毒检测方法的优缺点,为临床选择合适的梅毒检验方法.方法 随机选取已确诊为梅毒感染的患者446例和非梅毒感染的健康体检者398例.分别采用CLIA、TRUST、TPPA法对血清中的梅毒抗体进行检测,评价3种方法之间的差异及临床应用.结果 在对梅毒患者的血清检测中,CLIA、TRUST和TPPA的灵敏度分别为98.2％,80.3％和94.8％;特异度分别为98.5％、76.4％和99.7％.在对照组中,CLIA、TRUST和TPPA的假阳性率分别为1.5％、23.6％和0.2％.结论 CLIA的灵敏度高于TPPA,重复性好,操作简便,可用于梅毒初筛,但CLIA的特异度低于TPPA,因此CLIA的阳性标本应结合TPPA及临床症状确诊.TRUST的灵敏度及特异度均低于CLIA和TPPA.因此,TRUST主要用于梅毒的临床疗效观察.     

假丝酵母菌分离鉴定及药敏试验分析

目的监测院内假丝酵母菌感染菌种的分布及耐药情况,为临床抗真菌治疗提供依据。方法患者标本接种血平板、沙保罗、巧克力培养基,28～35℃培养24～48h,挑取可疑菌落涂片,革兰染色确认为酵母样真菌后转种假丝酵母菌显色培养基进行培养鉴定分型。采用纸片扩散法进行假丝酵母菌药敏试验。结果2006年3月—2008年11月从临床送检的2 196份标本中共检出假丝酵母菌118株,检出率为5.37%,其中白色假丝酵母菌65株(55.08%)、热带假丝酵母菌22株(18.64%)、近平滑假丝酵母菌17株(14.41%)、克柔假丝酵母菌14株(11.86%);在各种标本中以痰标本假丝酵母菌检出率最高84株占71.19%;各年龄段假丝酵母菌感染分布,60岁以上老年患者所占比例较大占77.1%;药物敏感试验显示,制霉菌素对假丝酵母菌敏感性最高,敏感率为85.7%～100.0%,而两性霉素B、酮康唑、伊曲康唑、5氟-胞嘧啶的敏感性较低。结论临床感染性疾病中假丝酵母菌感染占有一定的比例,加强真菌的分离及药敏监测对提高临床治疗效果有重要意义。     

Evaluation of general joint laxity, shoulder laxity and mobility in competitive swimmers during growth and in normal controls

The aim of the study was to evaluate differences between competitive swimmers and a reference group of school children concerning general joint laxity, laxity of the glenohumeral joint and range of motion in the shoulder. Materials and methods. Competitive swimmers (n = 120) were compared with references consisting of age and gender matched school children (n = 1277). General joint laxity was evaluated with the Beighton score. Anterior glenohumeral laxity was assessed according to the drawer test, and inferior glenohumeral laxity according to the sulcus test. Shoulder rotation was measured with a goniometer. RESULTS: Male swimmers of both age groups showed a higher degree of general joint laxity compared with the reference group while 9-year-old female swimmers alone had a lower degree of general joint laxity compared with references. No significant difference concerning shoulder laxity was noticed between groups. There was a decreased internal rotation in male and female swimmers as compared with the reference group. External rotation was reduced in female swimmers as compared with the female references. The same result was observed in male swimmers, but only at the age of 12 years. CLINICAL CONSEQUENCE: Competitive swimming in children seems to lead to a decreased range of motion with regard to shoulder rotation. However, the reason for this is still unclear and further investigations are needed.     

Evaluation of competing tests for the diagnosis of pulmonary embolism and deep vein thrombosis, part I

Tests for pulmonary embolism (PE) and its most frequent source, deep vein thrombosis (DVT), include angiography, ventilation-perfusion nuclear medicine scans, venous sonography with Doppler, and contrast and radionuclide leg venography. Although selective angiography is the definitive procedure for the diagnosis of PE, the associated risk of death, although small, as well as the morbidity associated with injection of contrast agents, are high enough that alternative, less accurate, but safer diagnostic procedures are performed in an attempt to avoid the higher-risk procedure. Effective cost (EC) of each test represents the dollars spent per unit of diagnostic information and is defined as the ratio of the expected direct cost (EDC) of the test to its diagnostic performance (DU). EDC includes the base cost or charge of the test and the estimated cost of the morbidity and mortality that can be incurred in performing the test, while DU is determined from the test sensitivity and specificity. With the lowest EC as the selection criterion for the best test and representative costs, sensitivity, specificity, and morbidity and mortality rates, five different tests for PE or DVT were compared. Doppler sonography yielded the most diagnostic information per dollar spent, as its EC was the lowest, primarily because its base cost was low compared to that of the other tests. Radionuclide leg venography had the second lowest EC. Selection among the remaining three tests depended on the prevalence of PE and morbidity and mortality costs. This methodology allows for comparison of individual tests in any given clinical setting as well as determination of the maximum cost and minimum performance characteristics for any new test to be competitive with already existing ones.     

Determinant factors in climbing ability: Influence of strength,anthropometry, and neuromuscular fatigue

The goal of this study was to (i) assess the physical and anthropometric differences between three levels of climbers and (ii) predict climbing ability by using a multiple regression model. The participants were divided into novice (n = 15), skilled (n = 16), and elite (n = 10) climbers. Anthropometric characteristics such as height, weight, percentage of body fat and muscle, bi‐acromial breath, arm span, and ape index were measured. General and specific strength were assessed through an arm jump test, a bench press test, and a hand and finger grip strength test in maximal and endurance conditions. All variables were combined into components via a principal component analysis (PCA) and the components used in a multiple regression analysis. The major finding of this study is that climbing ability is more related to specific rather than general strength. Only finger grip strength shows a higher level of initial strength between all samples while the arm jump test discriminates between climbers and non‐climbers. The PCA reveals three components, labeled as training, muscle, and anthropometry, which together explain 64.22% of the variance. The regression model indicates that trainable variables explained 46% of the total variance in climbing ability, whereas anthropometry and muscle characteristics explain fewer than 4%.     

~(14)C—尿素呼气试验筛选抗Hp治疗对象

建立小剂量~(14)-尿素呼气试验,结合胃镜、细菌培养和病理检查,对48例病人进行了研究。结果发现~(14)C-尿素呼气试验阳性者,胃镜下炎症程度及活动性明显高于阴性者。~(14)CO_2表达与胃粘膜炎症和Hp感染呈正相关。以~(14)CO_2值大于5000dpm作为筛选抗Hp感染临界值,所选病人经抗Hp治疗,症状、内镜下胃粘膜表现及Hp情况有明显疗效。提示,用~(14)C-尿素呼气试验可作为筛选抗Hp治疗指标之一,除避免了尿素酶试验,细菌培养和组织学检查受显色剂、培养条件及胃镜取材有局限性影响外,还解决了血清学不能确认Hp病人的问题,以~(14)CO_2值大于5000dpm选择治疗对象,可减少Hp耐药菌株和药物副作用的产生。     

Physical activity,functional capacity,and step variability during walking in people with lower-limb amputation

Physical activity is important for general health. For an individual with amputation to sustain physical activity, certain functional capacity might be needed. Gait variability is related to the incidence of falls. This study explored the relationship between physical activity and a few common performance measures (six-minute walk test, step length variability, step width variability, and comfortable walking speed) in individuals with unilateral lower-limb amputation. Twenty individuals completed the study (age: 50 ± 11 yrs). Twelve of them had transtibial amputation, seven had transfemoral amputation, and one had through-knee amputation. Gait data was collected by the GaitRite instrumented walkway while participants performed a 3-min comfortable walking trial followed by a six-minute walk test. Physical activity was indicated by the mean of 7-day step counts via a pedometer. Gait variability was calculated by the coefficient of variation. Pearson correlation analysis was conducted between physical activity level and the 4 performance measures. Significance level was set at 0.05. Physical activity correlates strongly to comfortable walking speed (r = 0.76), six-minute walk distance (r = 0.67), and correlates fairly to step width variability (r = 0.44). On the contrary, physical activity is inversely related to step length variability of the prosthetic leg (r = −0.46) and of the sound leg (r = −0.47). Having better functional capacity and lateral stability might enable an individual with lower-limb amputation to engage in a higher physical activity level, or vise versa. However, our conclusions are only preliminary as limited by the small sample size.     

Effect of blood on the morphological,biochemical and biomechanical properties of engineered cartilage

The use of autologous chondrocytes seeded onto a biological scaffold represents a current valid tool for cartilage repair. However, the effect of the contact of blood to the engineered construct is unknown. The aim of this work was to investigate in vitro the effect of blood on the morphological, biochemical and biomechanical properties of engineered cartilage. Articular chondrocytes were enzymatically isolated from swine joints, expanded in monolayer culture and seeded onto collagen membranes for 2 weeks. Then, the seeded membranes were placed for 3 days in contact with peripheral blood, which was obtained from animals of the same species and diluted with a standard medium. As controls, some samples were left in the standard medium. After the 3 days’ contact, some samples were retrieved for analysis; others were returned to standard culture conditions for 21 additional days, in order to investigate the “long-term effect” of the blood contact. Upon retrieval, all seeded samples showed increasing sizes and weights over time. However, the samples exposed to blood presented lower values with respect to the controls. Biochemical evaluation demonstrated a reduction in the mitochondrial activity due to blood contact at the early culture time (3 days post blood contact), followed by a partial recovery at the longer culture time (21 days post blood contact). Histological evaluation demonstrated evident cartilage-like matrix production for both groups. Biomechanical data showed a reduction of the values, followed by stabilization, regardless of the presence of blood. Based on the data obtained in this study, we can conclude that blood contact affects the chondrocyte activity and determines a delay in the dimensional growth of the engineered cartilage; however, at the experimental times utilized in this study, this delay did not affect the histological pattern and the biomechanical properties of the construct.     

Evaluation of competing diagnostic tests: Sequences for the diagnosis of pulmonary embolism, part II

Tests for pulmonary embolism (PE) and its most frequent source, deep vein thrombosis, include angiography, ventilation-perfusion nuclear medicine scans, and contrast and radionuclide venography. Although selective angiography is the definitive procedure for diagnosis of PE, its risk of death, although small, as well as the morbidity associated with contrast injections, is high enough that alternative, less accurate but safer, diagnostic procedures are preferred. Part I of this report described the methodology for selection of single test having the lowest effective cost based on the test cost, its risks, and diagnostic performance. Other than the pulmonary angiogram, however, no single test has a sufficiently high diagnostic performance to be clinically realistic: incorrect diagnoses can result in sudden death. Sequences of tests or algorithms can be used to lower the overall risk of the tests to patients while increasing correct decision making to reach a clinically acceptable level. These points are illustrated by comparing three commonly recommended algorithms for the diagnosis of PE. Additionally, the prevalence of PE affects the choice of the algorithm, and we found that no single algorithm is best for all values of prevalence. In summary, we found that the most costeffective strategy was to select the particular algorithm having the lowest effective cost for the relevant prevalence value. Useof algorithms also decreased the overall risk of diagnostic test complications and the number of incorrect diagnoses.