Perianal infections: Reader agreement and diagnostic performance of fat‐suppressed contrast‐enhanced MRI

We aimed to determine the diagnostic performance of the contrast‐enhanced fat‐suppression technique in the detectability of perianal infections and to compare this technique with different MR sequences used for this purpose. Thirty consecutive patients with clinically suspected anorectal infections were examined with fast spin‐echo (FSE) T2‐weighted, short‐inversion‐time inversion recovery (STIR), and fat‐suppressed and non‐fat‐suppressed T1‐weighted spoiled gradient‐echo (SGE) (in‐phase) dynamic contrast‐enhanced sequences. The results of MRI were correlated with the findings of surgery, which was considered as the standard of reference. Receiver‐operating‐characteristic curves were reconstructed to describe and compare the diagnostic value of each MR technique. The values of kappa were used as a measure of observer reliability. Diagnostic performances of STIR, FSE T2‐weighted and fat‐suppressed and non‐fat‐suppressed, contrast‐enhanced SGE T1‐weighted techniques showed statistically insignificant differences in detection of perianal infections. There was almost perfect interobserver agreement regarding the presence of lesions on each MR technique. Fat‐suppressed, contrast‐enhanced SGE T1‐weighted MRI showed adequate diagnostic performance in the detection of perianal infections. However, its significance is not different from the other MR sequences used for the present study.     

错畸形牙弓形态的模拟及比较

目的 :比较不同类型错牙合畸形的牙弓形态。方法 :采用三维测量仪精密测量正常牙合及 4组不同类型错牙合(ClassⅠ双颌前突、ClassⅡ1、ClassⅡ2 、ClassⅢ )的原始模型 ,圆锥曲线模拟其牙弓形态。结果 :不同类型错牙合牙弓形态的差异有显著性 ,甚至某些分组的上下颌之间牙弓形态的差异也有显著性。结论 :临床上弯制弓丝时采用单一的标准牙弓形态是不完全科学的 ,应考虑错牙合的不同类型及其矫治前不同的牙弓形态以防止畸形复发。     

Accessory scrotum with imperforate anus

Accessory scrotum is the rarest anomaly of the scrotum; less than two dozen cases have been reported. A case of accessory scrotum with imperforate anus is reported.     

Left Ventricular Anomalous Muscle Band and Electrocardiographic Repolarization Changes

A child with considerable electrocardiographic (ECG) repolarization abnormalities is reported in whom, after clinical and hemodynamic evaluation, only a large muscular false tendon within the left ventricular cavity was found. The genesis of the ECG changes in such cases is discussed, and the differential diagnosis from apical hypertrophic cardiomyopathy is analyzed.     

A Family Study of Autism: Cognitive Patterns and Levels in Parents and Siblings

First-degree relatives of 99 autism probands and of 36 Down's syndrome controls were assessed with standardised tests of intellectual functioning, reading, and spelling. Higher mean verbal IQ scores, and discrepancies in favour of verbal scores, were characteristic of autism relatives. No consistent differences were found on performance scales, reading, and spelling tests. Among autism relatives, siblings affected with the broad phenotype of autism had significantly lower IQ scores and poorer reading and spelling performances than unaffected siblings. However, the small size of the cognitive difference and the lack of a distinctive cognitive profile indicates that standardised cognitive measures used in this study are unlikely to improve the operationalised definition of the broad phenotype of autism. The slightly superior verbal performance of relatives in the autism group might represent some form of heterozygote advantage.     

桔梗扦插繁殖试验

对桔梗进行扦插繁殖试验，结果看出：用茎基部作插条的成活率最高（５２．２３％），茎梢部作插条成活率很低（１．１１％）；用激素处理可大大提高插条的成活率，其中ＮＡＡ（萘乙酸）１００ｐｐｍ处理３ｈ最显著，比对照组提高２３．３３％；扦插基质湿度过大，会引起插条腐烂。     

Morphology of Tricuspid Valve in Pulmonary Atresia with Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum (PAIVS) is a rare congenital cardiac anomaly that has been classified into two types: one is a more frequent type having dysplasia of tricuspid valve (TV) with a small annulus, underdeveloped right ventricle (RV) with a hypoplastic cavity and a hypertrophic wall; the other type has severe dysplasia of TV and dilatation of RV, right atrium (RA), and right atrioventricular junction with thinning of the RV wall. We performed a morphologic study on 11 autopsied hearts with PAIVS, giving particular emphasis to the variation of morphology of the TV. We could classify these hearts into 3 groups according to the degree of right ventricular development. In the first group of 7 cases (type I), the RVs were underdeveloped. Thick leaflets, restricted valve apparatus with short chordae, and small annuli were characteristics of the TV. In the second group of 3 cases (type II), the RVs showed marked enlargement of the cavity and thinning of the wall. The TV showed redundant, dysplastic, sail-like anterior leaflets, and the downward displacement of septal leaflet and/or posterior leaflet, which are the findings frequently observed in Ebstein's malformation. The RVs were dilated and with partially unguarded tricuspid orifice. The septal leaflet of the TV was dysplastic and, in two cases, the septal leaflet showed chordal structure at the upper surface facing the RA, which is a peculiar finding that has not been described in the literature. The remaining case was a heart with a moderately developed RV (type III). The TV showed mildly dysplastic appearance and we classify this as a separate type, because we could expect the best surgical results in this type. This type had optimal size of RV and the mildest degree of dysplasia of TV. In PAIVS, the morphology of TV correlates well with the type of the right ventricular development.     

延龄草组织培养研究

目的：探索延龄草Ｔｒｉｌｉｕｍｔｓｅｈｏｎｏｓｋｉ组织培养繁殖技术，为保护和利用这一珍贵药用植物提供新的技术途径。方法：以ＭＳ培养基为基本培养基，附加不同浓度的ＢＡ，ＩＡＡ，ＮＡＡ，玉米素，对不同器官，不同取材时期的延龄草外植体进行愈伤组织诱导和芽分化研究。结果：ＢＡ和ＩＡＡ有利于延龄草愈伤组织的诱导。生长旺盛的根茎是较适宜的培养器官，其愈伤组织诱导频率达２１９％，且较容易分化根茎而形成植株。结论：组织培养繁殖延龄草是一种可行的、具有应用潜力的生物技术方法。而如何进一步提高愈伤组织分化小根茎的频率，是建立延龄草组培繁殖技术的关键。     

新疆雪莲胚芽的组织培养和植株再生

目的:以新疆雪莲胚芽为外植体,建立一套新疆雪莲快速繁殖技术。方法:以MS培养基为基本培养基,通过研究植物生长物质BA和NAA对丛生芽的分化、丛生芽的增殖和生根的影响找出相应的最佳生长物质组合。结果:在附加NAA0.02-0.1mg·L^-1和BA2mg·L^-1的MS培养基上,所有的胚芽都可在45d内诱导出丛生芽;丛生芽切成小块后接入含NAA0.1-0.2mg·L^-1和BA2-3mg·L^-1的培养基中,都可在30d快速增殖;在含0.4mg·L^-1NAA的大量元素减半的MS培养基中,92%的不定芽可在25d内生根;再生植株移栽后,生长较好,成活率达70%。结论:新疆雪莲的胚芽可通过不定芽途径高频率的形成植株。     

Acetabular ossicles: normal variant or disease entity?

Ossicles located in the acetabular fossa may confuse diagnostic and therapeutic work-up. An accessory ossification centre may persist unfused as an os acetabuli centrale which is surrounded by intact hyaline cartilage representing an anatomic variant. Bone islands located in the pillars of the acetabulum can project into the acetabular fossa simulating acetabular ossicles. Osteochondrosis dissecans, posttraumatic articular bodies, degenerative disease and other rare lesions may be responsible for clinical symptoms and are of similar appearance than anatomic variants. Plain film radiography, X-ray tomography, CT and MRI are used to categorize these lesions. MRI is very valuable to assess cartilage integrity in a noninvasive way, but arthro-CT or arthro-MRI have to be used in unclear cases. Therefore the purpose of this presentation is to discuss the appearance, the possible etiology and the differential diagnosis of acetabular ossicles and how they can be evaluated to avoid an unnecessary arthrotomy. Received: 22 December 1998; Revised: 28 May 1999; Accepted: 8 July 1999