Carrier Frequency of the Bloom SyndromeblmMutation in the Ashkenazi Jewish Population

Bloom syndrome is more common in individuals of Ashkenazi Jewish descent than in any other population, and one particular mutation in the Bloom syndrome gene,blm^Ash,is homozygous in nearly all Ashkenazi Jewish persons with Bloom syndrome. We have determined the frequency ofblm^Ashin 1491 Ashkenazi Jewish persons with no known history of Bloom syndrome and found that 1 in 107 persons was heterozygous. Although not common, genetic screening for Bloom syndrome is feasible in this population.     

Clinical significance of the ST-segment response and other early exercise test variables in uncomplicated vs complicated myocardial infarction

An exercise test was performed in 455 patients in the thirdweek after acute myocardial infarction (AMI). One hundred andseventeen (26%) of them were considered as having a complicatedAMI. During a follow-up of 4.5 years their mortality was 49%vs 23% in the remaining patients with uncomplicated AMI. Thesurvival of the patients was assessed in each clinical groupin relation to various exercise variables. Exercise-inducedST-segment depression, irrespective of its degree, did not discriminatesignificantly between dead and living patients in any of theclinical groups. A high value of the rise of the pressure-rateproduct (PRP) from rest to maximal exercise (dPRP) and absenceof significant exercise-induced ventricular arrhythmias identifiedin both clinical groups patients with a very low risk of dying.A low dPRP and/or occurrence of significant ventricular arrhythmiasidentified a relatively high risk in uncomplicated AMI patientsand a very high risk of dying in complicated A MI subjects.The difference in the probability of survival between low-riskand high-risk patients was highly significant in each clinicalgroup (P<0.0001 in uncomplicated, and <0.005 in complicatedAMI, respectively).     

The effect of isosorbide-5-mononitrate (5-ISMN) Durules(R) on exercise tolerance in patients with exertional angina pectoris. A placebo controlled study

Twenty-four patients with stable exercise-induced angina pectorisentered a double-blind cross-over study. Isosorbide-5-mononitrate(5-ISMN) 60 mg in a controlled release formulation (Durules^®)given once daily was compared with identical placebo. The exercisetolerance was determined by bicycle ergometry before and 3 hafter a single dose of 5-ISMN and following one week's treatmentwith 5-ISMN and placebo. Nineteen patients completed the study.Exercise tolerance until the onset of chest pain and until 1mm ST segment depression increased significantly 3 h after dose.The same increase was seen both after a single dose and thesame dose under steady-state conditions. No increase was seenwith placebo. The heart rate and systolic blood pressure reactionsin the standing position were less pronounced 3 h after dosein steady-state than after a single dose of 5-ISMN. Headachewas the only bothersome side-effect reported. The study demonstratesthat 60 mg 5-ISMN in a Durules^® formulation given once dailyhas a significant anti-anginal effect and that tolerance doesnot develop.     

Mathematical model of volume kinetics and renal function after burn injury and resuscitation

This paper presents a mathematical model of blood volume kinetics and renal function in response to burn injury and resuscitation, which is applicable to the development and non-clinical testing of burn resuscitation protocols and algorithms. Prior mathematical models of burn injury and resuscitation are not ideally suited to such applications due to their limited credibility in predicting blood volume and urinary output observed in wide-ranging burn patients as well as in incorporating contemporary knowledge of burn pathophysiology. Our mathematical model consists of an established multi-compartmental model of blood volume kinetics, a hybrid mechanistic-phenomenological model of renal function, and novel lumped-parameter models of burn-induced perturbations in volume kinetics and renal function equipped with contemporary knowledge on burn-related physiology and pathophysiology. Using the dataset collected from 16 sheep, we showed that our mathematical model can be characterized with physiologically plausible parameter values to accurately predict blood volume kinetic and renal function responses to burn injury and resuscitation on an individual basis against a wide range of pathophysiological variability. Pending validation in humans, our mathematical model may serve as an effective basis for in-depth understanding of complex burn-induced volume kinetic and renal function responses as well as development and non-clinical testing of burn resuscitation protocols and algorithms.     

似昼夜节律与学习效应对脑事件相关电位P300的影响

目的 探讨昼夜节律和学习效应对脑事件相关电位P300成分的影响。方法 8名被试者在非连续的5d的实验中每天在5个时间点（7：00,12：00,16：00,20：00和0：00）重复相同的听觉Oddball模式测试以诱发脑事件相关电位（ERP）。然后测量各次的ERPP300成分,得到其潜伏期及波幅。结果 P300波幅明显高于下午的波辐。重复测量也使P300波幅从第1个实验日的平均13.0uV降至第5个实验日的9.2uV。P300潜伏期随着重复测试的增加出现了习服,它从第2个实验日的平均350.6ms缩短为第5个实验日的平均343.5ms.结论 似昼夜节律和学习效应对脑事件相关电位P300成分的波幅和潜伏期均有影响。     

A Dutch family with progressive sensorineural hearing impairment linked to the DFNA2 region

We studied a Dutch family with DFNA2-linked progressive sensorineural hearing impairment (SNHI). Recent audiograms were obtained from 18 of the affected persons (age 7–81 years) and were used in a gene-linkage analysis. Linear regression analysis of the audiograms, using binaural mean thresholds, disclosed on average a descending slope of approximately 10 dB/octave at any age and an annual threshold increase at any frequency of about 0.7 dB/year. There may have been substantial congenital impairment at higher frequencies, but longitudinal analysis of hearing impairment in the youngest case, who was followed from age 5 years, suggested that the most significant changes in hearing may have occurred in the first two decades of life. Linkage analysis was carried out with special attention to the DFNA2 region because hearing trends were very similar to families previously linked to DFNA2. Linkage to DFNA2 was established with maximum lod scores of 4.7 and 3.2 for the flanking markers of the DFNA2 region (D1S432;MYCL1). Received: 25 February 1999 / Accepted: 11 June 1999     

甘油三酯增高者畸变产物耳声发射的初步观察

目的：观察甘油三酯增高者变畸变产物耳声发射（ＤＰＯＡＥ）的振幅和潜伏期的变化情况。方法：采用ＩＬＯ－Ｖ５耳动态分析仪检测３０例（５５耳）甘油三酯增高者和１８例（３６耳）正常人的ＤＰＯＡＥ的振幅和潜伏期。结果：本组病例虽无纯音听阈异常,但ＤＰＯＡＥ振幅明显下降,而潜伏振幅值和明显。结论：甘油三酯增高者耳蜗功能可能有早期的损害,ＤＰＯＡＥ的反应幅值和潜伏期在产生机制和影响因素方面有所差异。     

腭裂儿童ABR表现的初步研究

目的探索腭裂儿童听力受损情况及其听性脑干反应(ABR)异常特征。方法对94例腭裂儿童进行ABR测试,并与正常对照组进行比较。结果94例患儿(188耳)中,不同程度的听力下降共150耳。患儿左耳ABR波Ⅰ、Ⅲ、Ⅴ的峰潜伏期(PL)分别为2.14±0.38、4.30±0.41、6.20±0.53ms;右耳分别为2.12±0.39、4.29±0.44、6.21±0.53。对照组左耳波Ⅰ、Ⅲ、Ⅴ的峰潜伏期分别为1.50±0.13、3.74±0.12、5.60±0.15ms;右耳分别为1.60±0.16、3.72±0.13、5.62±0.17ms。上述所有数据,患儿组与对照组比较,差异均有显著性(P<0.05)。＜3岁的28例听力下降的发生率为94.6%(53/56耳),中重度异常占66.7%;3～6岁的发生率为77.0%(57/74耳),6岁以上至12岁的发生率为69.0%(40/58耳),3岁以后听力中重度异常仅占33.3%。结论腭裂组听力下降发生率高达79.8%;其ABR的特点为波Ⅰ、Ⅲ、Ⅴ波的峰潜伏期均延长;腭裂组年龄越小的,听力损害发生率越高,听力损害程度越重。