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991.
A new surgical technique for the treatment of recurrent temporomandibular joint subluxation or dislocation is described. Following a horizontal osteotomy and down-fracture of the articular eminence an inter-positional bovine cartilage xenograft is inserted in order to augment the vertical height of the eminence. The procedure combines simplicity with minimal post-operative morbidity. The increase in eminence height is both predictable and stable.  相似文献   
992.
Deafness mutant mice show no stimulus-related cochlear potentials as well as abnormal electrically-evoked responses recorded from the inferior colliculus. Abnormal spontaneous activity in the auditory periphery could result in abnormal development and/or maintenance of the central auditory pathways. We therefore assessed spontaneous activity of cochlear origin in the central nuclei of the mutants by ablating one cochlea and subsequently using the 2-deoxyglucose (2DG) technique to study metabolic activity. Any asymmetries in labeling in a given nucleus should be due to spontaneous activity in the cochlear nerve on the unoperated side. In control animals (+/dn mice undergoing unilateral cochlea ablation), statistically significant decreased 2DG labeling was observed in the ipsilateral PVCN and AVCN, and contralateral MNTB and IC; all receive primary excitatory input from the ablated ear. No significant differences in labeling between right and left sides were observed in any of the nuclei studied in the mutant animals. These findings suggest that there is no spontaneous activity of cochlear origin in these mutants, even though many cochlear nerve fibers and spiral ganglion cells survive.  相似文献   
993.
The anatomic principles and operative techniques currently applied to functional endoscopic endonasal surgery have allowed for significant refinements in another approach to regional pathology that uses the operating microscope, newly designed sinus instruments, and a self-retaining nasal speculum system. The main benefits of this method are the superb widefield stereoscopic vision and the distinct freedom to work bimanually. Additionally, direct bipolar cautery of bleeders is afforded while use of the observer tube or video allows for excellent teaching. The precise nature of this surgery affords less fear of serious complications in the treatment of periorbital, paranasal sinus, and parasellar diseases. We describe technical aspects of the surgery and associated complications in 219 patients treated from 1984 to 1987.  相似文献   
994.
995.
Between June and September, 1986, an outbreak of measles occurred in Pilkhi Primary Health Centre area (population 56,000) in Tehri Garhwal district, Uttar Pradesh, India. Overall, 1092 cases were identified and 62 died; case-fatality ratio was 5.7%. Illness was restricted primarily to children below 15 years of age; 38% cases were in children under 5 and 58% between 5-14 years of age. To better characterize the outbreak, a survey was conducted in 13 affected villages. The age of the cases ranged from 5 months to 19 years (median = 7.0 years). The age-specific attack rates were 22.4%, 54.5%, 46.2% and 35.3% for children under 1, 1-4, 5-9, 10-14 years of age respectively. In as many as four villages, the attack rate in children below ten was 80% or more. Secondary attack rate among family members was 70%. Overall, 82% of children with measles developed complications which consisted mainly of pneumonia, diarrhoea and dysentery. The age-specific case-fatality ratios in infants and children 1-4 years of age were 23.1% and 11.5% respectively; thereafter the rates tended to decline with increasing age and was higher in females than in males (less than 0.05). Pneumonia which was a complication in 39% of measles cases contributed to 56% of deaths. Traditional beliefs and customs in the area were strong and did not encourage treatment of measles cases. Although a measles vaccination programme has been launched in India since 1985, only 30 districts could be covered during the first year and another 90 during 1986.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Thirty gallium scans, using currently acceptable dosage levels (5-6 mCi) and a conventional rotating gamma camera, were performed on 20 patients with lymphoma or infection. Compared to planar scans, SPECT increased sensitivity and lesion detection from 48% to 89% in lymphoma, and from 50% to 80% in infection. The predictive value of a negative site was 81% in lymphoma and 67% in infection. Gallium utility is markedly increased by SPECT imaging. A normal gallium SPECT scan is highly accurate in ruling out disease.  相似文献   
997.
Myelographic study of the spinal cord ascent during fetal development   总被引:2,自引:0,他引:2  
To assess the length of the spinal cord relative to the vertebral column during fetal development, we performed translumbar myelograms on 340 spontaneously aborted fetuses. Of these, 146 were selected for study. There were 76 males and 70 females, with fetal age ranging from 7 to 33 weeks. Significant variation in the level of spinal cord termination was found in fetuses between 12 and 25 weeks gestational age. In fetuses between 25 and 33 weeks gestational age, the cord ended at or above the third lumbar vertebra.  相似文献   
998.
The Scottish Heart Health Study is a study of lifestyle and coronary heart disease risk factors in 10,359 men and women aged 40-59 years, in 22 districts of Scotland. The study was conducted during 1984-86, when Scotland had the highest national coronary heart disease mortality reported by the World Health Organisation. A self-completed questionnaire, complemented by a 40 minute visit to a survey clinic, staffed by nurses, enabled the classical major risk factors and some more newly described ones to be measured. The study emphasised quality control and representativeness, and incorporated a World Health Organisation protocol for measurement of key items to allow comparisons in place and time, and therefore also to provide a definitive baseline against which interventions can be assessed. This paper describes the overall findings. Current cigarette smokers constitute 39% of men and 38% of women, higher levels than those reported in England but lower than previous Scottish reports. Mean blood pressure levels were 134/84 mmHg for men and 131/81 mmHg in women, lower than in British studies of the 1960s and 1970s. Mean body mass index levels, 26.1 Kg/m2 in men and 25.7 Kg/m2 in women, were not high by international standards. However, mean serum cholesterol levels were 6.4 mmol/l in men and 6.6 mmol/l in women--as high as those in previous British studies and high by international standards. Levels of high density lipoprotein cholesterol, non-fasting triglycerides and fibrinogen are also reported. Physical activity both at work and in leisure time was low.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
999.
1000.
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