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In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.  相似文献   
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Most lesions in FD and their attendant functional disability occur within the first decade; 90% of lesions are present by 15 years, and the median age when assistive devices are needed is 7 years. These findings have implications for prognosis and determining the timing and type of therapy. INTRODUCTION: Fibrous dysplasia of bone (FD) is an uncommon skeletal disorder in which normal bone is replaced by abnormal fibro-osseous tissue. Variable amounts of skeletal involvement and disability occur. The age at which lesions are established, the pace at which the disease progresses, if (or when) the disease plateaus, and how these parameters relate to the onset of disability are unknown. To answer these questions, we performed a retrospective analysis of a group of subjects with FD. MATERIALS AND METHODS: One hundred nine subjects with a spectrum of FD were studied for up to 32 years. Disease progression was assessed in serial (99)Tc-MDP bone scans by determining the location and extent of FD lesions using a validated bone scan scoring tool. Physical function and the need for ambulatory aids were assessed. RESULTS: Ninety percent of the total body disease skeletal burden was established by age 15. Disease was established in a region-specific pattern; in the craniofacial region, 90% of the lesions were present by 3.4 yr, in the extremities, 90% were present by 13.7 yr, and in the axial skeleton, 90% were present by 15.5 yr. Twenty-five of 103 subjects eventually needed ambulatory aids. The median age at which assistance was needed was 7 yr (range, 1-43 yr). The median bone scan score for subjects needing assistance was 64.3 (range, 18.6-75) compared with 23.1 (range, 0.5-63.5) in the unassisted subjects (p < 0.0001). Among subjects needing assistance with ambulation, 92% showed this need by 17 yr. CONCLUSIONS: The majority of skeletal lesions and the associated functional disability occur within the first decade of life. The implication is that the window of time for preventative therapies is narrow. Likewise, therapeutic interventions must be tailored to where the patient is in the natural history of the disease (i.e., progressive disease [young] versus established disease [older subjects]). These findings have implications for prognosis, the timing and type of therapy, and the development of trials of new therapies and their interpretation.  相似文献   
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Chondrons were isolated from human and canine osteoarthritic cartilage using low-speed homogenization techniques. Changes in chondron morphology were evaluated using differential interference-contrast microscopy, phase-contrast microscopy, and histochemical and ultrastructural methods. Chondrocyte viability was assessed using fluorescein diacetate staining, and chondron metabolism was investigated using autoradiography. The results suggest that initial changes in the collagen and proteoglycan distribution within the chondron are followed by chondrocyte proliferation to form clusters. These techniques offer the potential to study cell matrix interactions in degenerative osteoarthritis.  相似文献   
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This paper reports the results of a survey in which pregnant women in London and Edinburgh were asked about their knowledge and understanding of the recent recommendations of expert committees (James, 1983; DHSS, 1984). In general, Londoners had a better understanding, although in both regions manual groups were less knowledgeable, with the Edinburgh manual group the least well informed.  相似文献   
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Studies were done to compare the acute effects of streptozotocin-induced diabetes and sucrose consumption on micturition, bladder mass and contractile responses of bladder strips to field stimulation and contractile agonists. Micturition changes occurred gradually in diabetic rats, reached maximal values within 7 to 14 days, and were accompanied by significant increases in bladder mass after 7 days. Bladder strips from diabetics responded to field stimulation, carbachol and KCl with significantly greater contractions than did those from controls within 7 days. Sucrose-drinking rats had maximal increases in fluid consumption and micturition frequency on the first night after starting treatment. Increases in micturition volumes were slower to develop than in diabetics. Bladder mass was significantly increased 30 and 60 days after starting sucrose treatment. Bladder strips from sucrose-drinking rats responded to field stimulation and carbachol with significantly greater contractions than did those from controls only after 60 days. Monitoring of drinking and micturition patterns established that diabetic rats drink and urinate during both the dark and light cycles. In contrast, control and sucrose-drinking rats drink and urinate principally at night. The results demonstrate that differences in bladder function between diabetic and sucrose drinking rats are apparent during the first month after treatment begins. The data suggest that the effects of diabetes and sucrose consumption on contractile bladder function are related to the diuresis-induced increases in bladder mass.  相似文献   
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The principles of promoting autonomy and independence underpin many approaches to improving the quality of nursing care for older people in whatever setting, and are in line with wider developments in health care such as the Patient's Charter. However, these concepts require careful definition if nursing practices which might promote autonomy and independence are to be identified. Although the generalizability of the research-based literature in this field is limited by a focus upon older people in continuing-care settings, a review of the literature found a number of indicators associated with attempts to promote patient autonomy and independence. These were grouped into the following categories: systems of care delivery which promote comprehensive individualized assessment and multidisciplinary care planning; attempts to encourage patients/clients to participate in decisions about their care; patterns of communication which avoid exerting power and control over patients/clients and attempts to modify the environment to promote independence and minimize risk. It is suggested that the review identifies a number of principles for nursing practice which can be applied in a range of care settings in order to promote the autonomy and independence of older people.  相似文献   
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