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71.
BACKGROUND AND PURPOSE: Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR peifusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors.  相似文献   
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The parents of 80 victims of SIDS (Sudden Infant Death Syndrome) participated in this retrospective study. The semistructured interview included questions concerning events preceding infants' death and the situation at the discovery of the death. Fifty-eight of the 80 SIDS victims were male, twenty-two were female. Fourty-four of the babies underwent a postmortem examination. There was a high incidence of death during the winter months and concerning the hour of the day in the morning hours. Most families (91%) had no socioeconomic difficulties--in contrast to reports of other authors. In 34% of the SIDS cases the parents reported about stress or irregularities of the daily family life cycle (journey, mayor family events, quarrels) immediately before the death of the baby. About 20% of the victims were not in the usual surrounding at the time of death. In about 30% of the SIDS victims an infection was observed. Since between the 2nd and 4th month of life a major neuronal reorganization in the central nervous system is assumed (Prechtl, 1984), stress during this period may be particularly effective and dangerous for the baby. This would explain the high incidence of SIDS during this vulnerable phase (60%) in which the baby, apparently, is unable to react properly.  相似文献   
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Neurofibrillary degeneration, one of the pathological hallmarks of Alzheimer's disease, is not ubiquitous to all brain regions or neurons. While a high degree of vulnerability has been documented for entorhinal cortex, hippocampal and neocortical pyramidal neurons other brain structures are largely spared. Even within highly vulnerable regions such as hippocampus neurons are affected to a variable extent. The molecular basis for this selective susceptibility remains unknown. Neurofibrillary degeneration involves hyperphosphorylation of tau which critically impairs its binding capacity to microtubule and, therefore, is believed to disrupt the axonal cytoskeleton. Recently, Lu et al. [Nature (1999) 399:784] described the ability of the peptidyl-prolyl cis-trans isomerase Pin1 to recover microtubule-binding affinity and microtubule stabilisation of phosphorylated tau. In the present study, we analysed the potential involvement of Pin1 in selective vulnerability of hippocampal neurons to neurofibrillary degeneration in Alzheimer's disease. Pin1 immunoreactivity appeared as cytoplasmic granules affecting hippocampal subfields to a different extent (CA2>subiculum>CA1>CA3/CA4). Since the main markers of granulovacuolar degeneration do not co-label Pin1-immunoreactive granules, we propose that these granules may represent a new lesion in Alzheimer's disease. Neurons containing Pin1 granules were devoid of neurofibrillary tangles. Granular accumulation of Pin1 may correspond to an absence of neurofibrillary lesions in these cells and might be associated with other mechanisms of neuronal degeneration.  相似文献   
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Exercise-induced asthma: is it the right diagnosis in elite athletes?   总被引:6,自引:0,他引:6  
Exercise-induced asthma, as recognized in asthmatic subjects, is an exaggerated airway response to airway dehydration in the presence of inflammatory cells and their mediators. The airway narrowing is primarily caused by contraction of bronchial smooth muscle. The milder airway narrowing documented in response to exercise in elite athletes and otherwise healthy subjects may simply be the result of the physiologic responses and pathologic changes in airway cells arising from dehydration injury. These changes, which include excessive mucus production and airway edema, would serve both to cause cough and to amplify the narrowing effects of normal bronchial smooth muscle contraction, resulting in symptoms. These changes are more likely to occur in healthy subjects who exercise intensely for long periods of time breathing cold air, dry air, or both. Under these conditions, the ability to humidify inspired air may be overwhelmed, causing significant dehydration of the airway mucosa and an increase in osmolarity, even in small airways. In addition to dehydration injury, airway narrowing to pharmacologic and physical agents may occur as a result of injury caused by large volumes of air containing irritant gases, particulate matter, or allergens being inspired during exercise. As a result, the airways may become inflamed, and the airway smooth muscle may become more sensitive. These events could result in the same exaggerated airway response to dehydration, as documented in asthmatic subjects.  相似文献   
78.
Autoantibodies to the heat shock protein 90 (Hsp 90) have been reported as prognostic marker in breast cancer patients. Sera from 20 high-grade osteosarcoma patients were tested at the time of diagnosis by enzyme-linked immunosorbent assay. Presence of anti-Hsp90 antibodies correlated with a better response to neoadjuvant chemotherapy (P < 0.01), whereas the absence correlated with development of metastases. These data suggest that anti-Hsp90 antibodies might be of predictive value in human osteosarcoma.  相似文献   
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The goal of the present study was to investigate whether a direct association exists between false-positive recognition of IgG antibodies and inflammatory changes in the central nervous system (CNS) and whether inflammatory diseases of the CNS affect the specificity of the enzyme-linked immunosorbent assay (ELISA) of tick-borne encephalitis (TBE) virus. A group of patients (1,815), treated in the Department of Neurology, University Hospital of the Saarland, Homburg/Saar, Germany, were tested forTBE IgG antibodies by ELISA. Several subgroups of patients with and without inflammatory changes in the CSF as well as patients with and without confirmed multiple sclerosis (MS) were investigated. Overall, 4.5% of all the 1,815 patients and 4.8% of the patients with inflammatory changes in the CSF but without MS had TBE IgG antibodies. In the subgroup with inflammatory changes in the CSF and MS, 4.4% of the patients were TBE IgG-positive. In the subgroup without inflammatory changes in the CSF, 3.8% of the patients without MS were TBE IgG-positive and 4.9% of the patients with MS were TBE IgG-positive. The rate of TBE IgG positivity was not significantly different in the subgroups with and without inflammatory changes in the CSF (P = 0.45). The comparison of the subgroups with and without MS showed no significant difference in the TBE IgG titer (P = 0.83) as well. This indicates that the specificity of the ELISA was affected neither by inflammatory changes in the CSF nor by MS.  相似文献   
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