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101.
The effect of intraarticular infusions of albumin solution on transsynovial flow was studied in healthy rabbit knee joints and compared with the effect of albumin solution perfused through the synovial microcirculation. Increasing intravascular albumin levels enhanced fluid absorption from the joint cavity, whereas increasing intraarticular albumin levels reduced the absorption rate. The slope of intraarticular pressure-versus-absorption rate plots was reduced by albumin in proportion to the reduction in fluidity (1/viscosity). When joint pressure was held constant, the transsynovial absorption rate was reduced by albumin in excess of the fluidity reduction and even reversed to filtration into the joint cavity. Thus intraarticular albumin acts by a dual mechanism, namely by increasing synovial interstitial fluid viscosity and by exerting a peri-capillary oncotic pressure. However, the latter effect was much less than that of intravascular albumin. Reasons for this are discussed.  相似文献   
102.
The authors report the case of a 33-year-old woman who exhibited, at the age of 17, a left-sided hemiplegia, which was followed by good motor recovery, though with a permanent deficit in fine finger movements. She had a widespread loss of neural tissue in the right hemisphere (crossed cerebrocerebellar atrophy), including (1) marked atrophy and thinning of the precentral and postcentral gyri; (2) widespread deep white matter destruction, including the corticospinal tract; and (3) crossed cerebellar atrophy. Except over the supplementary motor area (SMA), transcranial magnetic stimulation did not elicit motor evoked potentials in the affected hand. Nevertheless, during opening and closing of the affected hand, functional magnetic resonance imaging showed an activation of the lesioned primary sensorimotor cortex (SMC), as well as of the intact SMA and the parietal areas, but not of the ipsilateral motor areas. The authors speculate that recovery was achieved by a motor command generated in the SMC and the parietal cortex, passing through corticospinal axons originating in the SMA.  相似文献   
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BACKGROUND: To adequately address the complex health needs of young people, their access to services, and the quality of services received, must be improved. AIMS: To explore the barriers to service provision for young people and to identify the training needs of primary healthcare service providers in New South Wales (NSW), Australia. DESIGN OF STUDY: A cross-sectional, qualitative study of the perspectives of a range of health service providers. SETTING: A range of primary healthcare organisations across NSW. METHODS: Samples of general practitioners (GPs), youth health workers, youth health coordinators, and community health centre staff were drawn from urban and rural clusters across NSW. Focus groups and interviews were used to identify barriers to service provision and the training needs of service providers. Data were tape recorded, transcribed, and analysed. RESULTS: Barriers to service provision among GPs and community health centre staff included inadequate time, flexibility, skills, and confidence in working with young people, and poor linkages with other relevant services. Training needs included better knowledge of and skills in adolescent health requirements, working with adolescents, and working with other services. Barriers to service provision for youth health workers and coordinators included lack of financial resources and infrastructure. There were few linkages between groups of service providers. CONCLUSION: Models of service provision that allow stronger linkages between service providers, sufficient time for consultation with young people, adequate training and support of health professionals, and flexibility of service provision, including outreach, should be explored and evaluated.  相似文献   
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Through the case report of severe digitalis intoxication in a premature born after 27 weeks of gestation with a birthweight of 800 g, the authors show that anti-digoxin antibodies constitute a very efficacious therapeutic tool which, up to the present, has not been used in prematures.  相似文献   
108.
The issue of the preparation of effective teachers becomes more critical for teachers of early childhood programs. It has been hypothesized that better program quality depends on better-educated teachers. The purpose of this investigation was to explore the importance of a high level of education for all early childhood education teachers. This issue has intrigued early childhood researchers and has prompted a large amount of research studies over the past decades. In order to assess the status of this line of inquiry and to provide guidance for future research, a critical analysis of 40 studies on the preparation of early childhood education teachers and the quality of their educational programs that were published within a 15-year (1989-2004) period is presented here. The analysis consisted of literal and allegorical critical analysis and interpretative critical analyses, which generated results in three main areas that focused on the professional development of the teachers, including teachers' professional development, the importance of a Bachelor's Degree and educational standards for early childhood education teachers.  相似文献   
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A magnetic resonance imaging study of putamen nuclei in major depression.   总被引:7,自引:0,他引:7  
The basal ganglia are recognized as putative mediators of certain cognitive and behavioral symptoms of major depression. Moreover, patients with basal ganglia lesions have repeatedly exhibited significant affective symptomatology, including apathy, depressive mood, and psychosis. Using high resolution, axial T2 intermediate magnetic resonance images, and a systematic sampling stereologic method, we assessed putamen nuclei volumes in 41 patients with major depression (DSM-III) and 44 healthy volunteer controls of similar age. Depressed patients had significantly smaller putamen nuclei compared with controls. Age was negatively correlated with putamen size in both groups. These results are the first demonstration of diminished putamen volumes in depression and further support a role for basal ganglia structures in the etiopathogenesis of depression.  相似文献   
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