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961.
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963.
Stable labeling of red blood cells (RBCs) with 99mTc, in yields of about 66%, was achieved by using stannous chloride as a reducing agent. In a study of 12 patients, the stability of technetium-labeled RBCs in the circulation varied significantly among individuals, but the average biologic half-life of the labeled cells was 16.8 hr. Although the labeling yield was lower when the labeling was carried out without EDTA with the addition of stannous chloride after the pertechnetate, this sequence appears to be the best for labeling RBCs for use in obtaining images of the blood pool or the cardiovascular system because of the increased viability of the RBCs.  相似文献   
964.
Evidence that host genetic factors play a major role in susceptibility or resistance to many infectious diseases is increasing, due to major advances in genetic epidemiological methodology. Recent human genome mapping information and the identification of a large number of candidate genes provide the tools for such studies. The information obtained is important for understanding the pathogenesis of disease and for the design of preventive and therapeutic strategies. In the study of Chlamydia trachomatis disease pathogenesis, much research focuses on how bacterial factors modulate the immune response and thus contribute to the disease process. It is likely, however, that host factors also play a role, and therefore susceptibility to disease is the result of an environmental effect set against a background of genetic factors. This review outlines the evidence for the contribution of host genetic factors to susceptibility to C. trachomatis disease in humans.  相似文献   
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OBJECTIVES: The aim of this study was to examine the selegiline treatment compared to methylphenidate (MPH) in children and adolescents with attention deficit hyperactivity disorder (ADHD). METHOD: Forty subjects, aged 6-15 years, boys and girls, who were diagnosed as having ADHD, using the criteria of the Diagnostic and Statistical Manual of Mental Disorders- Fourth Edition (DSM-IV), were randomly assigned to receive either selegiline or MPH for 60 days. Treatment outcomes were assessed using the Attention Deficit Hyperactivity Scale (ADHS) administered at baseline and on days 14, 28, 42, and 60 following the commencement of treatment. Side effects were also rated. RESULTS: There were no significant differences between sex, age, weight, and ethnicity of participants in the 2 groups. Both groups showed a significant improvement over the 60 days of treatment resulting from the teachers' and parents' ADHS scores across the treatment. CONCLUSION: Following the trial, MPH did not effect greater mean improvement as a result of the parents' or teachers' ADHS scores than selegiline. Thus, selegiline appears to be effective and well tolerated for ADHD in children and adolescents.  相似文献   
968.
Portions of the ependyma were obtained from the hippocampus of adult rabbits and processed for scanning electron microscopy. The major part of the ependymal surface was covered with a dense layer of cilia, some of these cilia showed bulbous preterminal enlargements. Irregularly arranged pits of variable diameter were also seen. Pes hippocampi showed fewer cilia and deeper furrows than did the remainder of the hippocampus.  相似文献   
969.
Dysfunction of brain vascular endothelial cells may be associated with the pathogenesis of several diseases including cerebral amyloid angiopathy, hemorrhagic stroke and Alzheimer disease. New model systems are necessary to examine the contribution of brain endothelial cells in these disorders. The Von Willebrand factor gene promoter fragment that spans sequences -487 to +247 targets the expression of LacZ marker gene in transgenic mice specifically to brain vascular endothelial cells. Transgenic mice have been prepared that express human amyloid beta protein precursor protein (AbetaPP) isoforms 695 and 751 (wild-type and Dutch variant mutations) under the regulation of this VWF promoter sequence. These AbetaPP transgenes are specifically expressed in brain vascular endothelial cells. The VWF promoter is a valuable tool for targeting gene expression to brain vascular endothelial cells to provide a model to directly examine endothelial cell placement of genes and their contribution to cerebral vascular disease.  相似文献   
970.
Computed tomographic (CT) scans in cerebral palsy (CP)   总被引:1,自引:0,他引:1  
The CT findings in 120 cerebral palsied children are analysed. The 72.5% positive findings are correlated with the clinical types, as well as the aetiological basis for the cerebral palsy. The spastic type, 83.3% of the total number of children, had the highest positive findings. The yield was increased in children with seizures (91.3%) and those in the postnatal group (90%), as well as those with birth trauma and neonatal asphyxia (94%). The findings were those of atrophy in 30.8%, hydrocephalus, in 10%, infarct in 11.6%, porencephaly in 8.3% and others. The atropic changes and their patterns are explained. Treatable lesions, such as tumour, hydrocephalus, subdural haematoma, porencephaly and hygroma were identified in 22.5% of cases. It is concluded that CT scan is definitely efficacious in the management of cerebral palsied children.  相似文献   
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