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81.
Summary The presence of Lewy body and neurofibrillary tangle in the locus ceruleus neurons of aged brain is described. Ultrastructural study revealed that in some Lewy bodies the presence of twisted tubules or paired helical filaments amongst the filaments of the Lewy body. A quantitative analysis of serial sections of locus ceruleus from aged brain, incidences of the Lewy body and neurofibrillary change were 0.07% (9/11,515) and 6.6% (15/11,515), respectively. The incidence of neurons containing both structures was 0.008% (1/11,515).  相似文献   
82.
Neovascular glaucoma is one the most difficult forms of glaucoma to treat successfully. Recent advances modifying filtration surgery can result in up to 77% success. Utilization of anterior and posterior segment photocoagulation can maintain an open angle in up to 80% of eyes when they are treated prior to angle closure by peripheral anterior synechiae. Destruction of the ciliary body can be performed more selectively utilizing argon and ruby lasers. This paper presents a rational approach to the management of neovascular glaucoma incorporating these recent advances.  相似文献   
83.
Laboratory of Neurophysiology of Brain Integrative Activity and Section Brain and Behavior,, A. I. Karaev Institute of Physiology, Academy of Sciences of the Azerbaijan SSR, Baku. (Presented by Academician of the Academy of Medical Sciences of the USSR O. S. Adrianov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 3, pp. 227–229, March, 1991.  相似文献   
84.
This study has analyzed variations in the number of nucleoli and nuclear bodies, as well as in their ultrastructural and cytochemical organization, after the osmotically induced activation of supraoptic nucleus (SON) neurons of the rat. The number of nucleoli and nuclear bodies and also the nucleolar size were determined on smear preparations of previously block-impregnated SON. The mean number of nucleoli per cell was 1.35 +/- 0.6 (mean +/- SDM) in control rats. No significant variations in this value were registered either in dehydrated or rehydrated rats. The mean nucleolar volume and the total nucleolar volume per cell showed a significant increase in dehydrated rats with respect to the controls, whereas these two parameters tended to return to control values in rats rehydrated after dehydration. The mean number of nuclear bodies per cell increased significantly from 0.56 +/- 0.50 (mean +/- SDM) in control rats to 1.54 +/- 1.1 after 6 days of dehydration. By electron microscopy, SON neurons displayed a reticulated nucleolar configuration. After the osmotically induced neuronal activation, there was an increase in the proportion of the total nucleolar area occupied by the granular component, and also a reduction in the mean fibrillar-center area. The most characteristic nucleolar features in rehydrated rats were the tendency for the granular component to be segregated and the occurrence of intranucleolar vacuoles. Ultrastructural cytochemistry with a specific silver method revealed a selective silver reaction on the coiled threads of the nuclear bodies--identified as "coiled bodies"--and on the nucleolar fibrillar components in all animal groups studied. Since nucleoli play a major role in ribosome biogenesis, a relationship between these nucleolar changes and the level of cellular activity of SON neurons is proposed. Furthermore, the response of nuclear "coiled bodies" to neuronal activation suggests their participation in the processing and transport of rRNA precursors.  相似文献   
85.
Seven percent of 400 patients with cervical spine fractures and/or dislocations had unusual lesions of the axis. The authors have analyzed axis injuries by review of radiographs and clinical data and have derived a classification of traumatic conditions. Uncommon traumatic axis abnormalities are discussed with reference to incidence, causes, clinical findings, mechanism of injury, and roentgen characteristics.Picker Scholar, James Picker Foundation  相似文献   
86.
87.
BACKGROUND: Body mass index (BMI) is the simplest way to measure obesity; therefore, it is chosen by many authorities as a screening method for adolescent obesity. Body mass index is positively correlated with the complications of childhood and adolescent obesity, such as hypercholesterolemia, insulin resistance, hyper-tension and long-term development of cardiovascular diseases. The aim of the present study was to produce percentile curves for bodyweight, height and BMI in a representative sample of adolescent girls living in urban and rural areas of Edirne, Turkey, and to compare these percentile curves with curves from other countries. METHODS: The present study was a cross-sectional study, including a representative sample of 1687 adolescent girls from rural and urban areas of Edirne, who were evaluated between May and July 2001. Bodyweight and height were measured using standard procedures. Body mass index (kg/m2) was calculated as the ratio of bodyweight to body height squared. Smoothed percentiles for these variables were calculated using polynominal regression models. Crude weight, height and BMI percentile values, as well as smoothed percentile curves are presented. RESULTS: Body mass index, weight and height reference curves for adolescent girls were produced. When we compared the BMI values of subjects in the present study with those of other countries, 85th and 95th percentiles of BMI in the present study were found to be generally lower than those for other ethnicities. CONCLUSION: Our findings show ethnic differences in BMI among adolescent girls. It will be usefull for each country to produce its own BMI percentiles.  相似文献   
88.
迁移性咽和颈段食管异物4例   总被引:1,自引:0,他引:1  
目的:探讨迁移性咽和颈段食管异物的临床特征、诊断及治疗方法。方法:对位于腔壁内的异物,应尽量选用内镜下切开黏膜取出;若异物已移至腔外,则采用颈侧切开术。结果:4例患者均顺利取出异物,3例无并发症发生,1例声带麻痹。结论:颈部薄层CT扫描是证实异物迁移的重要手段,并对手术时定位异物有重要价值;食入异物出现迁移者,可产生致命性并发症,应及时处理。  相似文献   
89.
The aspiration of a bronchial foreign body (FB) remains a common pediatric problem with serious and sometimes fatal sequelae. The diagnosis is often delayed or overlooked. With the aim of determining a reliable clinical and/or radiologic finding to indicate the requirement for bronchoscopy, 100 patients admitted to our hospital because of FB aspiration who underwent rigid bronchoscopy were retrospectively studied. The clinical and radiologic data were compared with the bronchoscopy findings, which revealed that the history of a choking crisis was the clinical parameter that showed the highest sensitivity (97%) with high specificity (63%), and that other symptoms and radiology, even those with high sensitivity (88% and 85%, respectively), had low specificity (9%). We conclude that bronchoscopy should be performed in all patients with a history of a choking crisis even if they have normal radiologic findings and few symptoms.  相似文献   
90.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph.  相似文献   
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