A Note on the Asymptotic Properties of Affected-sib-pair Linkage Tests

This article concerns the asymptotic properties of linkage tests for affected‐sib‐pair data under the null hypothesis of no linkage. We consider a popular single‐locus analysis model where the unknown parameters are the disease allele frequency, the three penetrances for the three genotypes at the disease locus, and the recombination fraction between the marker locus and the disease locus. These parameters are completely confounded under the null hypothesis of no linkage. We show that 1) If the total variance of the trait (i.e., the additive variance plus the dominance variance) is “separated” from 0, then the likelihood ratio statistic has an asymptotic 0.5χ²₀+ 0.5χ²₁ distribution; 2) If the prevalence of the trait is “separated” from 0 and the recombination fraction is fixed at 0, then the likelihood ratio statistic has an asymptotic distribution which is a mixture of χ²₀, χ²₁ and χ²₂ . The implications of these results are discussed.     

Digital computer analysis of dermatoscopical images of 260 melanocytic skin lesions; perimeter/area ratio for the differentiation between malignant melanomas and melanocytic nevi

BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.     

Ventricular enlargement, clinical correlates and treatment outcome in chronic schizophrenic inpatients.

The ventricle-brain ratio (VBR) of 42 chronic schizophrenic patients was compared with that of 42 age-matched medical controls. For the schizophrenics, the relationship of various clinical parameters to the VBR was assessed, and the outcome of 12 weeks of double-blind treatment with either risperidone or haloperidol. The results confirm that schizophrenic patients have slightly enlarged lateral ventricles compared with medical controls. Only for schizophrenics, an effect of age, but not of duration of illness, was noticed. This study does not support the validity of a clinical subdivision of chronic schizophrenic patients on the basis of the VBR. Neither negative, positive nor general psychopathological symptoms, as measured by the Positive and Negative Syndrome Scale for Schizophrenia (PANSS), were related to the VBR, nor were abnormal involuntary movements or extrapyramidal symptoms. No association between season of birth or a family history of major mental disorder and VBR could be demonstrated. Treatment response was predicted by the total PANSS score and the PANSS general psychopathology subscale score at baseline. There was a trend for patients with higher VBR to have a more or haloperidol). or haloperidol).     

Phosphate end dialysis value : a misleading parameter of hemodialysis efficiency

Despite low end dialysis serum phosphate levels (P_e) the control of phosphate retention remains often unsatisfactory in dialyzed patients. In order to assess the value of P_e in dialyzed children as an indicator of dialytic phosphate removal, we studied serum phosphate kinetics over the period of dialysis and post dialysis and compared these with urea kinetics. A multicenter study was conducted in the 21 French pediatric hemodialysis units and included 144 children under 15 years of age. Blood urea and phosphate concentrations were measured at the beginning, at 45 min later, at the end of dialysis, and 30 min post dialysis. At 60 min and at 360 min post dialysis measurements were made only for a subgroup of 12 children. From the serum levels, reduction ratios for urea (URR) and phosphate (PRR) and post dialysis rebound for urea (PDUR) and phosphate (PDPR) were calculated. URR (over the dialysis session, 72%±9%) was higher than PRR (47%±12%). Moreover, urea removal continued throughout the dialysis period, while most of the reduction in phosphate occurred in the initial dialysis period. Post dialysis urea rebound was limited to the 60th min post dialysis, whereas post dialysis phosphate rebound occurred until the 360th min post dialysis; by this time the serum phosphate levels had almost reached the predialysis levels. In summary, serum phosphate kinetics over dialysis and post dialysis periods in children appear to be misleading for the quantification of phosphate removal, i. e., phosphate clearance is a poor indicator of dialytic phosphate removal. Received September 21, 1995; received in revised form and accepted June 11, 1996     

锯齿缘断离术式选择与疗效的关系

报告５０例（５３眼）锯齿缘断离视网膜脱离的临床特点与术式，正确地选择术式视网膜复位率达１００％，其中１次复位率为９０．５７％，讨论了４种术式的适应症，作用原理和复位率。认为正确选择术式与疗效有密切关系。     

哺乳妇女单次注射迪波盖司通~长效避孕针后血清和乳液中MPA浓度变化

目的:探讨中国妇女哺乳期使用迪波盖司通后血清和乳液醋酸甲羟孕酮(MPA)浓度变化。方法:10名产后哺乳妇女单次注射迪波盖司通(含MPA150mg),在注射后的第1、2、4、6、8、10和12周采集血样和乳液样本,用放射免疫方法测定MPA。结果:血清MPA浓度于注射后第1周最高,到第2、4周时下降明显,第4周后浓度下降趋势逐渐缓慢。乳液MPA浓度在第1周为最高,第2周比第1周降低了约1/2,之后10周平均浓度变化波动在5.09-8.15ng/ml之间。观察期间乳液/血清MPA浓度比值和曲线下浓度面积比值均为0.55。对象之间和同一对象不同时间点乳液/血清MPA浓度存在明显个体差异。结论:哺乳期使用迪波盖司通,将导致血液和乳液中含有一定量的MPA。     

青少年近视患者配戴渐进多焦眼镜的视光学检查现状初步分析

目的:调查青少年近视患者配戴渐进多焦眼镜的现状,分析其对眼部参数的影响。方法:随机抽查配戴渐进光眼镜的近视患者214名,对其进行视光学检查,包括屈光度、斜视度、AC/A率、辐接近点和融合范围等项目,并调查其心理感受。其检查结果与256名年龄相匹配的戴用单焦眼镜的近视患者相对照,分析其变量的变化。结果:配戴渐变多焦眼镜的近视患者中140例无不适感觉,满意程度明显高于对照组;屈光度平均为-3.5D,约半数患者(48.6％)存在不同程度的外隐斜,其中8位是间歇性外斜患者,没有融合能力,辐辏近点大于20 cm;平均AC/A率为(2.95±1.49),平均融合力为+16.41°～-7.06°,平均辐转近点为(72.63±24.42)mm。实验组除AC/A率低于对照组(t=3.52,P<0.05),且与屈光度无明显相关(r=-0.0318,P>0.05)外,其余检查与对照组之间没有显著性差别。结论:渐进多焦眼镜可以引起AC/A率降低,并有可能通过掩饰间歇性外斜患者 的症状而耽误其治疗。因此,渐进多焦眼镜虽然普遍受青少年近视患者欢迎,但验配中仍存在适应证选择问题,青少年在验配时最好在医生的指导下进行。     

Urethral closure function in women with prolapse

In 19 patients with different types of severe descensus, all without clinical evidence of stress incontinence, urethral stress pressure profiles and stress tests were done before and after repositioning of the prolapse. In 13 of the 19 patients, continence was artificial, because during repositioning they showed leakage of urine; however, 6 of the patients remained continent. The pressure transmission ratios decreased in different parts of the urethra in all the patients when repositioning with a gynecological speculum was done. The drop was most significant in those patients who lost urine after repositioning, showing poor urethral function. In women with genito-urinary prolapse, a test of urethral function is essential, even if there is no clinical evidence of incontinence after removal of the descensus. In cases of severe stress incontinence under this condition, a procedure for bladder neck stabilization should be added to routine prolapse surgery.     

焦痂提取液中丙二醛含量对线粒体呼吸及内膜能化作用的影响

大鼠背部20％光辐射Ⅲ度烧伤7天后的焦痂提取液及1:4、1:8稀释液能对正常大鼠肝线粒体呼吸产生明显的抑制作用,相同方法制成的正常皮提取液只呈轻度抑制,1:4稀释液已无抑制作用,两者丙二醛含量相差悬殊,丙二醛含量与抑制率呈相关,但进一步分析表明这种相关为共存现象,丙二醛含量增高不是呼吸率下降的直接原因。丙二醛增高与膜脂双层的破坏有关,内膜能化作用实验表明,当膜脂受到一定程度破坏时,能化作用受到抑制。然而在能化作用未表现异常时,呼吸率已呈一定程度抑制,故呼吸率抑制还受到提取液其他组分的影响。     

Evaluation of the percentage of sperm motility at 24 h and sperm survival ratio for prediction of in vitro fertilization

Summary. The present study was carried out to investigate the predictive value of the percentage of sperm motility after 24-h incubation and sperm survival ratio from semen and inseminated sperm suspension using grading of motility by WHO criteria with respect to the fertilization of oocytes in vitro. A total of 789 oocytes from 85 cases were inseminated and the mean fertilization rate obtained was 72.5%. There was no significant correlation between all of the sperm motility results with fertilization rate in vitro. All sperm motility results were not significantly different between the non-fertilizing group and the fertilizing group and also between the group of fertilization rate ≤ 25th percentile (fertilization rate ≤62.5%) and the group of fertilization rate >62.5%. However, the initial percentage of rapid progressive sperm motility and progressive motility in semen and inseminated sperm suspension at 24 h gave significant differences between the group of fertilization ≤ 50th percentile (fertilization rate ≤80%) and the group of fertilization rate >80%. Overall accuracy using these parameters for prediction of fertilization rate >80% was only about 60%. In conclusion, the percentage of sperm motility at 24 h and sperm survival ratio in both semen and inseminated sperm suspension have no practical value in predicting fertilization rate in vitro. Moreover, detailed motility grading cannot improve the predictivity of these sperm motility parameters.