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1.
The purpose of this study was to investigate radiographic measurements in a cohort of patients with juvenile hallux valgus (with a hallux valgus angle > 15 degrees ) using standardized weightbearing x-rays compared with an age-matched control group. First metatarsal protrusion distance, metatarsus primus adductus angle, metatarsus adductus, first metatarsal cuneiform angle, calcaneal inclination angle, and talocalcaneal angles were assessed with discriminant functional analysis. A total of 37 sets of data were analyzed from patients with a mean age of 13.45 +/- 1.75 years. The study identified 2 significant components of juvenile hallux valgus: a positive first metatarsal protrusion distance (P <.001) and metatarsal primus adductus angle (P = .002). Discriminant functional analysis was then used to determine the best predictors of juvenile hallux valgus. This analysis allowed only 1 variable, metatarsal protrusion distance, as a predictor of whether juvenile hallux valgus was present (P < .001), with 94.3% accuracy. This study showed that a positive metatarsal protrusion distance is a significant component of juvenile hallux valgus.  相似文献   
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The Low Vision Clinic at the Palmerston North Hospital has now been oerating for 70 years. Over the course of these ten years a number of factors have emerged which can be as readily applied to general ophthalmological practice as to low vision practice. The philosophy of low vision care is one of which all ophthalmologists should be aware and includes factors to be taken into account when dealing with children, people in the workplace, and everyday factors involved in daily living activities, all of which are equally relevant in routine ophthalmological practice. This paper endeavours to share some thoughts on these factors and also discusses means by which the visually handicapped can be helped in areas where specialist low vision services are not readily available.  相似文献   
4.
The calculation of the extent of the ring scotoma around positive lenses, as conventionally taught to students of clinical optics, indicates that the scotoma is of a significant size. Using knife-edge lenses this study shows that the calculations are invalid due to the finite size of the eye's entrance pupil and in many instances the scotoma is shown not to exist. The effect noticed in clinical practice is probably largely due to the frame and the edging techniques used which add to the refractive scotoma which is present with high powered lenses, large apertures and/or small pupil sizes.  相似文献   
5.
In two experiments, children were taught a word and then given reminders of that word while reading unfamiliar analogous words. Reminders of the pronunciation of taught words facilitated reading of rime analogous words (e.g. b eak -p eak ) over head analogous words (e.g. bea k- bea n) in Experiment 1, and onset analogous words (e.g. st ilt- st em), over medial analogous words (e.g. e.g. st ilt-mi lk ) in Experiment 2. Importantly, however, privileged improvement for rime and onset analogous words was not evident in the absence of these concurrent prompts. The findings suggest that the analogy model developed by Goswami (1993) may have limited applicability in naturalistic settings.  相似文献   
6.
The recovery of the ability to read of a patient affected by persistent visuospatial neglect suggests the functional independence of the two phenomena. Neglect dyslexia seems to be an example of a dissociation between an implicit and explicit knowledge of the characteristics of the stimulus.
Sommario Il recupero della capacità di lettura in un paziente con persistente neglect visuo-spaziale suggerisce l'indipendenza funzionale dei due fenomeni. La neglect dyslexia sembra costituire un esempio di dissociazione tra conoscenza implicita ed esplicita delle caratteristiche dello stimolo.
  相似文献   
7.
Dimension of contact is the very moment when meeting with someone. The limits can be precisely defined as an aesthetic moment, i.e. the very moment when someone appears. That is an experience of one's expressivity. One can usually go through this ephemeral moment to reach simple self-continuity. Pathologies of contact may be described at different levels: neurosis, pathological personalities and psychosis.  相似文献   
8.
中长跑和芭蕾舞运动中胫骨应力骨折的比较   总被引:3,自引:0,他引:3  
胫骨应力骨折(SF)在芭蕾舞和中长跑运动员中均有一定发病率,作者调查某部新兵265人每日5000米跑步,其胫骨应力骨折病发率为11.68%(31/265人),骨折部位多在胫骨中段中后侧。芭蕾舞演员胫骨应力骨折病发率为8%(15/60人),骨折部位在胫骨下段前侧。应用新鲜尸体标本作负荷下胫骨多处的应变测定模拟跑步和足跟垫高模仿芭蕾舞时下肢负重位置的应变变化,分别于胫骨中段后侧测得有高压应力和胫骨下段前方有高张应力,此结果与调查中X线片病变部位相符。作者认为不同的运动使负重时胫骨所处姿势各不相同,而造成胫骨最大应力集中点位置各异,是造成芭蕾舞运动和中长跑运动中应力骨折部位不同的主要原因,预防和治疗工作应根据各自的应力性质和集中点部位来进行防治。  相似文献   
9.
在以往对八年制医学生开展读书报告活动的基础上,2007年,北京大学医学部病理生理学教研室首次专门为医学生讲述如何撰写医学文献综述.教师首先具体介绍什么是文献综述,进而通过列举实例详尽讲述文献综述的构成,并教授医学生文献检索和利用网络资源的技巧和方法.通过此次讲述,2004级八学制学生在文献综述撰写中出现的问题较以往有所减少,使其对文献综述的撰写更为得心应手.  相似文献   
10.
Inanimate structures cannot detect and repair their fatigue damage or microdamage, so to minimize it they need more structural material and strength. Living bone handles this matter differently. Bone modeling drifts adapt bone architecture and strength to the loads on bones in ways that tend to keep strains from exceeding a “modeling threshold” range. Strains (or equivalent features) above that threshold switch mechanically controlled modeling ON. Where strains stay below that threshold, this modeling goes OFF. Repeatedly loading-deloading a bone causes microdamage in it, and basic multicellular unit (BMU)-based bone remodeling normally repairs it. Where strains stay below an operational “microdamage threshold,” remodeling can repair whatever microdamage happens for as long as it happens. Strains above that threshold can cause too much microdamage to repair completely and lead to fatigue fractures of trabeculae or whole bones. The modeling threshold normally lies comforably below the microdamage threshold. Since modeling normally adjusts bone architecture to keep strains from exceeding the modeling threshold, this keeps strains below the microdamage threshold, too, and voluntary activities do not cause more microdamage than remodeling can repair. Therefore, long-distance runners do not need more bone mass and strength than nonrunners of comparable age, sex, and body size.  相似文献   
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