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991.
75,000 SEVERELY DISABLED CHILDREN   总被引:1,自引:1,他引:0  
This article explores the epidemiological potential of the computerised record of applications to the Family Fund, which contains details of 75,000 children with severe disabilities in the UK. It illustrates the strengths and weaknesses of the record, with an analysis of variation in the characteristics of the children and their families by principal handicapping conditions.  相似文献   
992.
Unilateral injury to the forelimb-representation area of the sensorimotor cortex (FL-SMC) in adult rats results in use-dependent proliferation of dendritic processes, followed by partial pruning, of layer V pyramidal neurons of the contralateral homotopic cortex. In development, `exuberant' growth of neurons is often followed by pruning, a process that has been associated with a glutamatergic-NMDA receptor mechanism. A related mechanism may play a role in injury-related pruning of dendrites in adults. The N-methyl-d-aspartate (NMDA) receptor antagonist MK801, administered throughout the pruning phase to adult animals with FL-SMC lesions, prevents dendritic pruning and disrupts behavioral recovery. Ethanol (ETOH) also acts as an NMDA receptor antagonist. It has been shown to reduce NMDA-active ion currents, inhibit NMDA-evoked electrophysiological responses, and decrease glutamate-binding in the hippocampus and cortex. ETOH also affects neuromorphology in the developing and adult cerebellum, hippocampus, and cortex. Ethanol's involvement with NMDA receptor function and its influence on dendritic morphology led us to examine its effect on dendritic pruning and behavioral recovery following unilateral FL-SMC lesions. Lesioned animals were exposed to moderate doses of ethanol in a liquid diet only during the period of dendritic pruning. As with MK801, ETOH prevented pruning and reinstated chronic behavioral asymmetries.  相似文献   
993.
For 50 years, the three- and five-year survival rates of under 40% for invasive ovarian cancer in the USA have not significantly changed. Identifying those women who have a greater probability of developing the disease should contribute to improving survival. Our 3-year case-control study of 298 women from the metropolitan Washington, DC, area with primary epithelial ovarian cancer revealed a woman is at greater risk of developing ovarian cancer if she has a family history of the disease, experiences difficulty becoming pregnant, and has a normal menopause with hot flashes. Her risk for the disease is diminished with multiparity, a history of dysmenorrhea, and hysterectomy. Physicians should consider these risk factors when performing pelvic examinations in women and coordinate them with known changes in ovarian size and procedures to view the ovaries which may permit earlier recognition of ovarian cancer.  相似文献   
994.
A case-control study of incident invasive cervical cancer was conducted in Birmingham, Alabama; Chicago, Illinois; Denver, Colorado; Miami, Florida; and Philadelphia, Pennsylvania, during 1982-1983. Controls were selected by random-digit dialing and were matched to cases by age, race, and telephone exchange. Of the white, non-Hispanic cases and controls identified, 271 (73%) and 502 (74%), respectively, were successfully interviewed. Diet was assessed by asking about the usual adult frequency of consumption of 75 food items and the use of vitamin supplements. Included were the major sources of the four micronutrients believed to reduce the risk of cervical cancer: carotenoids, vitamin A, vitamin C, and folate. Women in the highest quartiles of intake of each of these micronutrients had adjusted relative risks of invasive squamous cell cervical cancer comparable to those of women in the lowest quartiles, although their micronutrient intake was estimated to be 3-4 times as high. Risk was not affected by increased consumption of vegetables, dark green vegetables, dark yellow-orange vegetables, fruits, or legumes, or by high intake of the basic food groups. These generally negative findings stand in contrast to findings in previous epidemiologic studies, and the discrepancy is not readily explained by bias, uncontrolled confounding, or inadequate power. The question of the role of diet and nutrition in the etiology of cervical cancer is not yet resolved.  相似文献   
995.
Flunitrazepam has been reported to be a very potent muscle relaxant (12). The dose-response relationship for depressant action of this drug on contralateral extensor reflexes was studied in midcollicular decerebrate and acute spinal cats. The reflex response was more sensitive to the depression of the drug in midcollicular than in acute spinal preparations. The dose required to reduce the reflex response by 50% was about 3 μg/kg in midcollicular preparations, whereas a dose of 15 μg/kg was required to depress the response to the same degree in spinal cats. The stimulation experiments showed that this drug also depressed the facilitation and inhibition of the knee jerk produced by activating the brain stem reticular system. The dose-response curve of the effects of this drug on mesencephalic reticular and spinal internuncial neuronal activity revealed that depression occurred at both levels. These findings suggest that the higher potency of flunitrazepam is attribulable not only to its highly potent depressant action on the mesencephalic reticular system but also to its substantial depressant action on the spinal interneurons.  相似文献   
996.
Optic disc drusen in children   总被引:1,自引:0,他引:1  
Forty children with pseudopapilledema due to optic disc drusen (31 bilateral, nine unilateral) were studied retrospectively to characterize the early natural history of this condition. The average age at the first examination was 10.2 years (range 3.6 to 19.5 years), and the mean follow-up period was 44 months. Discrete hyaline bodies or papillary calcifications were first noted in one or both eyes with pseudopapilledema at a mean age of 12.1 years in 38 of 40 cases. Decreased visual acuity due to drusen occurred in only one eye due to subretinal neovascularization. Visual fields obtained in 35 eyes (21 patients) with pseudopapilledema showed an enlarged blind spot (9), an inferior arcuate/sector/or altitudinal defect (6), or both (3) in 18 eyes. Our study suggests that discrete papillary calcifications or hyaline bodies frequently emerge and visual field deficits are commonly detectable in the second decade of life in patients with pseudopapilledema due to optic disc drusen.  相似文献   
997.
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999.
Traditionally, it has been accepted that conductive deafness involves a breakdown in the mechanical conduction of sound, whilst the cochlea remains unaffected. Over a ten year period, it was noticed that a number of patients, mainly children, displayed a mild, hightone sensorineural component to their conductive loss, whereas others tested under identical conditions with parallel etiologies did not. A sample of 80 children with chronic otitis media and sensorineural involvement was selected from Prince Henry's Hospital and Alfred Hospital, Melbourne, and was compared with 80 children with the same histories, but whose audiograms did not display any sensorineural involvement. The results of this study indicate a need for further research into: 1. The establishment of an internationally acceptable terminology. 2. Early detection of chronic otitis media. 3. Medical/surgical management. 4. The effects on hearing, caused by fluctuating nature of chronic otitis media. 5. Educational and social management.  相似文献   
1000.
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