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11.
The case describes a female patient with squamous cell carcinoma of the lung who initially presented with mechanical upper-back and neck pain. She had been successfully treated with spinal manipulation for a similar complaint one year earlier, a factor that decreased the suspicion of pathological process on her second presentation. Serious disease as the cause of back pain must be considered in cases with certain historical factors, or when the patient fails to respond to treatment for mechanical back pain.  相似文献   
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There is increasing interest in the influence of community characteristics on child development and family functioning. In order to address questions on community influence, it is important to be aware of the measures available and their strengths and limitations. Useful strategies have been developed within a number of disciplines, including sociology, social and community psychology, and criminology. Methods include summarising information from existing administrative databases and census data, conducting observations, and using survey instruments with residents. The most commonly used methods are reviewed and their psychometric properties described .  相似文献   
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Cognitive theory holds that dysfunctionalattitudes are important risk factors for depression.Critics have questioned this view, noting that, althoughdysfunctional attitudes are elevated in depression, they are not evident in vulnerable individualswho are asymptomatic. To deal with this criticism,Miranda and Persons (1988) have advanced the mood-statedependent hypothesis, which suggests that cognitive vulnerability factors are indeed present invulnerable individuals, but remain dormant untilactivated by negative mood. To test this hypothesis, 33women with and 67 women without histories of depression reported dysfunctional attitudes before andafter a film negative mood induction. As predicted,vulnerable subjects who reported increased negative moodreported increased dysfunctional attitudes.Unexpectedly, nonvulnerable subjects who reported increasednegative mood reported decreased dysfunctionalattitudes. These findings support the mood-statedependent hypothesis, and suggest that a deficit in theability to regulate negative emotions may be animportant feature of vulnerability todepression.  相似文献   
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The immortalization of progenitor cells from embryonic murine hippocampus using oncogene‐carrying retroviral vectors is described. Use of a vector encoding the oncogene v‐myc results in lines of nestin‐positive progenitor cells. Limited differentiation ensues if the cells are cultured in the presence of dibutyryl cyclic adenosine monophosphate. In contrast, use of a vector in which the extracellular portion of the epidermal growth factor (EGF) receptor is fused to the neu tyrosine kinase generates lines of pluripotential nestin‐positive progenitor cells, which differentiate upon withdrawal of EGF into neurons and glia. Differentiated neurons expressing action potentials and neurotransmitter receptors make up a high proportion of the cells. These cell lines are useful tools to investigate the characteristics of differentiating neurons and glia, as well as to screen neuroactive drugs. This work has been reported in preliminary form as an abstract (1996 Society for Neuroscience Abstract, #606.20, p. 1537).  相似文献   
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Elevated levels of very long-chain fatty acids (VLCFA) in plasma and tissues are the biochemical hallmark for patients with X-linked adrenoleukodystrophy (X-ALD). Current methods for the determination of VLCFA levels are laborious and time-consuming. We describe a rapid and easy method using electrospray ionization mass spectrometry (ESI-MS) with deuterated internal standards. VLCFA are hydrolyzed, extracted, and quantified in less than 4h. This includes 2h of hydrolysis and 4min of quantification. We validated the method by analyzing 60 plasma samples from controls and patients with X-ALD or Zellweger syndrome using both the ESI-MS protocol and an established method for VLCFA analysis using gas chromatography (GC). The C26:0 concentrations determined with ESI-MS in plasma and fibroblasts of X-ALD patients are in good agreement with those reported previously for GC and GC-MS. Besides saturated straight chain VLCFA, we also determined the concentrations of the mono-unsaturated VLCFA C24:1 and C26:1 and established that while C24:1 levels are not elevated, C26:1 levels are elevated in both plasma and fibroblasts from X-ALD patients.  相似文献   
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Thirteen infants with achondroplasia underwent psychometric testing as part of a comprehensive neurologic assessment. As a group, mental development was average and motor development was delayed, although a wide range of scores was obtained. Foramen magnum measurements were correlated with respiratory dysfunction, abnormal so-matosensory evoked potentials, and delayed motor development. Abnormal polysomno-gram outcome was associated with reduced mental capacity. In light of the reported increased frequency of respiratory dysfunction in achondroplasia, these findings warrant careful attention and further study.  相似文献   
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