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91.
92.
The purpose of this study was to determine the causes of childhood visual impairment and blindness in students of a school
for blind children, to determine how many students had some residual vision, and to evaluate any unmet low-vision care. A
survey of students in the blind school was conducted in two parts in May–June and then October 2003. The sample consisted
of 201 students who became blind before the age of 16. Information was obtained from student interviews, doctors’ referral
notes and ophthalmic examination of all students who consented. Students with residual vision had low-vision assessments.
These investigations were supplemented with active participation of the investigators in Parent–Teacher Association meetings
and focus group discussions with parents. One hundred and ninety-nine students consented and were recruited, whereas two declined.
Ninety-six became visually impaired within their first year of life and 33 by the age of 5 years. Pathology of the cornea
and then the lens were the commonest causes of blindness. One hundred and eight students were totally blind, whereas 87 (43.7%)
had some residual vision and formed the target for the second part of the study. Fifty-one out of 77 of this target group
who turned up for low-vision examination had useful residual vision by the World Health Organisation (WHO) low-vision examination
chart. Spectacle magnifiers aided two students to read normal print at N5 and N8, respectively. Different visual aids would
help enhance the residual vision in some of the others. Emotional trauma was apparent in parents and teachers. Children who
became blind later in life remained in shock for a longer time and adapted less well to their visual impairment. Visual impairment
in the population is not uncommon. Some causes are preventable. There is a significant unmet need for low-vision care, particularly
amongst children in Ghana, and perhaps many countries in the West Africa subregion. It is hoped that the findings from this
study will help spur sustained interventions.
相似文献
W. M. K. AmoakuEmail: |
93.
This field study tested and demonstrated the validity and reliability of the Quadri-Track Zone Comparison Technique designed for specific Single-Issue Psychophysiological Veracity (PV) examinations using the polygraph, using one hundred and forty confirmed real-life cases from a private polygraph firm under contract with a metropolitan police department. The Quadri-Track Zone Comparison Technique's unique Inside Track accurately increased the scores for the innocent by 43.6% and the guilty by 37.1% thereby reducing the overall inconclusive rate from 19.5% to 1.4%, which effectively remedies the major cause (Fear/Hope of Error) of inconclusive results in single-issue polygraph tests. The Quadri-Track Zone Comparison Technique correctly identified 100% of the innocent as truthful with no inconclusives and no errors. It further correctly identified 97.8% of the guilty as deceptive and 2.2% as inconclusive, with no errors. Inconclusives excluded, the Quadri-Track Zone Comparison Technique was 100% accurate in the identification of the innocent and the guilty. Inconclusives included, the utility rate was 98.6%. Blind scoring of polygraph charts showed extremely high correlations for the individual and total scores with a combined accuracy of 98.3%. 相似文献
94.
目的:研究一种将心电噪声信号从脑电信号中分离出来的算法及其DSP硬件实现。方法:癫痫是一种中枢神经系统疾病,该病的诊断主要依靠脑电监测,但由于人体是一个复杂网络,临床采集到的脑电通常会混有其他噪声如心电干扰,这为后续的处理引入不可控制的误差。本文采用基于遗传算法的独立分量方法实现多通道脑电信号的盲源分离。结果:通过相关临床专家检验,认为该方法基本能够去除心电噪声,和参考心电信号对比具有一致性。结论:通过从北京某三甲医院癫痫中心采集到的患者脑电数据进行测试,对比试验表明,该方法是一种稳健高效的处理方法,符合并行运算的特点,整套算法可以移植到基于DSP的嵌入式系统架构上,具有一定的实用价值。 相似文献
95.
Automatic removal of eye movement and blink artifacts from EEG data using blind component separation 总被引:19,自引:0,他引:19
Signals from eye movements and blinks can be orders of magnitude larger than brain-generated electrical potentials and are one of the main sources of artifacts in electroencephalographic (EEG) data. Rejecting contaminated trials causes substantial data loss, and restricting eye movements/blinks limits the experimental designs possible and may impact the cognitive processes under investigation. This article presents a method based on blind source separation (BSS) for automatic removal of electroocular artifacts from EEG data. BBS is a signal-processing methodology that includes independent component analysis (ICA). In contrast to previously explored ICA-based methods for artifact removal, this method is automated. Moreover, the BSS algorithm described herein can isolate correlated electroocular components with a high degree of accuracy. Although the focus is on eliminating ocular artifacts in EEG data, the approach can be extended to other sources of EEG contamination such as cardiac signals, environmental noise, and electrode drift, and adapted for use with magnetoencephalographic (MEG) data, a magnetic correlate of EEG. 相似文献
96.
Verginia Cretu Doru Vlad Popovici Wendy Sainsbury 《Developmental neurorehabilitation》2013,16(4):305-317
This article reviews the educational facilities available in the last decades of the 20th century for blind and partially sighted children and young people in Romania and the UK. A turning point in England and Wales came with the Education (Special Educational Needs) Act 1981. For Romania, the turning point came in 1990 with the overthrow of the Ceaucescu regime in late 1989. Romania is seeking entry to the European Union in 2007. This has provided an incentive to bring special educational philosophy and facilities quickly into line with other countries in the European Union. Similar problems regarding inclusion are encountered in both countries. Differentiating features are their different demographic characteristics and the educational resources and assets available at the time of the major changes. Finally, there is a brief review of the number of people with sight loss in paid employment as the next logical focal point for a national inclusion strategy. The UK has been able to develop and advance further than Romania in this sphere, but the legal framework is in place in Romania. The generic terms visually impaired (VI) and sight loss are both used throughout when referring to blind and partially sighted people.Resumen: Este artículo revisa y reflexiona sobre algunos de los cambios legislativos educacionales más importantes, que han tenido lugar en los últimos 25 años, en Inglaterra, Gales y Rumania, afectando la educación de los niños y gente joven con alteraciones visuales (AV). Mientras que se reconoce la importancia del concepto de inclusión de gente con discapacidad en todos los aspectos de la educación y de la sociedad, este artículo reconoce también que el progreso hacia la inclusión de la gente con discapacidad aún muestra imperfecciones. En el Reino Unido (UK), el nivel de preparación en la esfera educativa, antes disponible para los individuos con afecciones visuales, se ha disipado y ahora es difícil localizarla en algunas áreas de Inglaterra y Gales. A partir de un plan nacional de escuelas y colegios especiales segregados hace 25 años, el sistema educativo para alumnos con AV sin discapacidades adicionales ha alcanzado ahora una posición de inclusión casi total en las escuelas estatales. Sin embargo, la opción de selección aún permanece abierta con la existencia continua, aunque en diferente forma, de varias escuelas especiales independientes. Para muchos en el Reino Unido, esta elección puede ser ilusoria debido a limitaciones financieras ejercidas por las autoridades educacionales locales. En Rumania el progreso hacia una mayor inclusión en escuelas principales aún requiere de fondos a futuro y un entrenamiento profesional extenso. La primera parte inicia con la historia de la educación para niños con AV en ambos países, junto con la legislación reciente y la situación actual. La segunda parte examina algunas de las dificultades encontradas en los dos países en el camino hacia la educación de inclusión, para después tratar el tema de los prospectos de empleo para gente con AV al final de su educación. Palabras clave: Ciego, débil visual, deficiente visual, inclusión, educación especial. 相似文献
97.
王建军 《神经疾病与精神卫生》2016,(3):323-324
目的:探讨表现为单眼失明的一侧颈内动脉闭塞患者的特点。方法选取2011~2015年收入我院的5例以单眼失眀为表现的颈内动脉闭塞患者,分析患者的临床特点。结果5例患者均先就诊于眼科,经眼底荧光造影证实为动脉闭塞;经DSA证实为单侧颈内动闭塞、眼动脉闭塞。经动脉溶栓治疗,2例恢复,1例经球后注射后较前恢复,1例仅有光感,1例未恢复。结论当无诱因突然发生单眼失明时应警惕颈内动脉闭塞。 相似文献
98.
In laser lithotripsy, it has been found that calculi fragmentation is always accompanied with the formation of a plasma which
has two characteristics, i.e. the acoustic signal or shock waves, and the optical signal or plasma emission. By monitoring
the feedback signals of the shock waves, the temporal behaviour and the spectra of plasma emission, the feasibility of so-called
blind fragmentation has been investigated. The shock wave feedback is found to be not as reliable as the plasma emission feedback
and the use of an optical multichannel analyser system to detect, analyse and display the spectra of the feedback plasma emission
has proved to be reliable and direct for blind fragmentation. The blind fragmentation technique has been found to be successful
in ex vivo experiments in which stones were inserted into pigs' ureters and then fragmented without the use of a ureteroscope.
It has also been investigated in vivo in studies from about one dozen patients, and for the first time a series of the plasma
spectra have been obtained and analysed in vivo. These indicate promising prospects for the clinical application of the technique
and, in addition, application to real-time stone composition analysis. The technique has also been tested for biliary stone
fragmentation and for laser angioplasty, again the results have shown good prospects. 相似文献
99.
E. Schippers V. Schumpelick 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(2):99-104
Zusammenfassung Störungen der intestinalen Motilität, bakterielle Fehlbesiedlung und pankreozibale Asynchronie werden im Patienten nach Roux-Y-Rekonstruktion (RYR) beschrieben. Im Tierexperiment (Hund, n = 6) ergab die elektromyographische Registrierung der Motilität nach 2/3-Resektion des Magens mit Roux-Y-Rekonstruktion in der Roux-Schlinge keinen signifikanten Unterschied zu Kontrollwerten. Ausgeprägt sind jedoch die Veränderungen der Motilität in der blinden Schlinge. Das elektromyographische Bild ist sowohl in der Nüchternphase als auch postprandial gekennzeichnet durch einen erheblichen Aktivitätsverlust. Eine Aktivitätsfront des migrating motility complex trat nur in 25% der Nüchternexperimente auf und war zeitlich nicht mit der Motilität angrenzender Darmabschnitte koordiniert. Nach Nahrungsaufnahme war der Motilitätsindex mit 27,8 ± 4,1 in der blind endenden Schlinge ebenfalls deutlich geringer als in der Roux-Schlinge (60,2 ± 10,5). Pharmakologisch ist die ausgeprägte Hypomotilität der blinden Schlinge mit Cisapride zu durchbrechen — Anstieg des Motilitätsindex auf 111,2 ± 16,5. Bei Patienten mit RYR und klinischer Symptomatik ist daher ein therapeutischer Einsatz zu erwägen.
Motility disturbances in the blind loop after Roux-en-y reconstructionElectromyographic studies in dogs
Disturbances of intestinal motility, bacterial overgrowth and pancreocibal asynchrony are frequent findings in patients after Roux-en-y reconstruction (RYR). In dogs (n = 6) electromyographic recording of motility after partial gastrectomy with Roux-en-y reconstruction revealed no significant differences from controls in the Roux limb. However, changes in intestinal motility were extensively in the blind loop. The electromyographic pattern was characterized by an extreme loss of activity in the fasted and postprandial state. The activity front of the migrating motility complex occurred only in 25% of the fasting studies and was not correlated in time with motility patterns of connected small intestine. Food intake led to a significant increase in the motility index in the Roux limb (60.2 ± 10.5), but not in the blind ending loop (27.8 ± 4.1). Pharmacological stimulation of the hypomotile blind loop with cisapride is successful; increase of the motility index to 111.2 ± 16.5. It might be useful in the treatment of symptomatic patients after RYR.相似文献
100.
To solve the future food insecurity problem, alternative and sustainable protein sources (e.g. insects, rapeseed, fava bean and algae) are now being explored for the production of food and feed. To approve these novel protein sources for future food a comprehensive risk assessment is needed according to the European food legislation. Allergenicity risk assessment might pose some major difficulties, since detailed guidance on how to assess the allergenic potential of novel foods is not available. At present, the approach relies mostly on the guidance of allergenicity assessment for genetically modified (GM) plant foods. The most recent one was proposed by EFSA (2010 and 2011); “weight-of-evidence approach”. However this guidance is difficult to interpret, not completely applicable or validated for novel foods and therefore needs some adjustments. In this paper we propose a conceptual strategy which is based on the “weight-of-evidence approach” for food derived from GM plants and other strategies that were previously published in the literature. This strategy will give more guidance on how to assess the allergenicity of novel food proteins and protein sources. 相似文献