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Members of 183 families (biological parents and one adult offspring) completed questionnaires on their quantity and frequency of alcohol use, what they would consider a "normal" quantity-frequency of alcohol use, "problem" quantity-frequency of use, flushing after alcohol use, and other expected physiological and subjective responses to alcohol. Within individuals, own quantity-frequency of alcohol use was moderately negatively correlated with flushing after one drink or less ("fast flushing"), but more highly positively correlated with judged normal alcohol use and with expected subjective effects. Spouse resemblances were low for quantity-frequency of alcohol use and flushing, but high for alcohol use norms and expected physiological and subjective responses. Parent-offspring resemblances were low to moderate for own alcohol use and flushing, but moderate to high for expected physiological and subjective effects. These results were discussed in terms of the effects of genetically transmitted flushing after alcohol use and culturally transmitted alcohol norms and expectations on alcohol use.  相似文献   
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In this report of opisthotonos during recovery from propofol anaesthesia, we relate clinical observations with scientific considerations, and propose a strategy for treatment of this rare side effect. Following a brief operative procedure, a healthy 29-yr-old woman developed recurrent opisthotonos while recovering from anaesthesia with alfentanil, propofol, and nitrous oxide. In contrast to accumulating reports, the patient remained conscious during each episode of back extension and retrocollis. The preservation of consciousness and similarities to strychnine-induced opisthotonos suggest to us that the mechanism may have a brainstem and spinal origin. Recent investigations show that propofol potentiates the inhibitory transmitters glycine and γ-aminobutyric acid (GABA) which would enhance spinal inhibition during anaesthesia. Postanaesthetic opisthotonos, however, may be due to a propofol-induced tolerance to inhibitory transmitters. This rebound phenomenon would lead to an acute, enduring refractoriness in inhibitory pathways of the brainstem and spinal cord, resulting in increased activity of extensor motoneurons. We recommend a therapeutic strategy that restores inhibition by glycine and GABA at multiple sites; the preferred therapeutic agents would be diazepam and physostigmine. The episodes are usually short-lived, but two of the reviewed 17 patients developed recurrent retrocollis for four and 23 days following antiepileptic drug therapy. Since high doses of phenytoin and carbamazepine can result in opisthotonos, we recommend that anticonvulsants be reserved for post-anaesthetic patients with electroencephalographic evidence of seizure activity.  相似文献   
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Valproate is effective in treating bipolar disorder characterized by rapid cycling or acute mania, although the mechanism of action is unclear. In contrast to other treatments for depression, 21 days of treatment in rats with valproate (100, 200 or 400 mg/kg) did not significantly alter the hypothermia induced by 8-hydroxy-2-(di-n-propyl)aminotetralin (8-OH-DPAT), an agonist at serotonin-1A receptors. Treatment with valproate also had no effect on radioligand binding to serotonin-1A, serotonin-2 or -adrenergic receptors. Based on these animal studies in frontal cortex and hippocampus, the therapeutic benefit of valproate in mood disorders does not appear to involve adaptive changes in serotonin-1A, serotonin-2 or -adrenergic receptor number.  相似文献   
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Molecular genetic studies of early breast cancer evolution   总被引:9,自引:0,他引:9  
Summary In the past few years there has been an explosion in the number of patients diagnosed with hyperplastic breast disease andin situ breast cancer. Based on epidemiological data, these morphologically defined lesions may be categorized as those with little malignant potential (e.g. typical hyperplasia or proliferative disease without atypia [PDWA]), those with significant malignant potential which may already be initiated (e.g. atypical ductal hyperplasia [ADH]), and early transformed lesions which are malignant but not yet invasive (e.g. ductal carcinomain situ [DCIS]). They may represent sequential evolutionary stages in the ontogeny of invasive breast cancer, with each morphologically defined stage resulting from accumulating genetic changes culminating in a transformed clonal lineage capable of invasion and metastasis. Using loss-of-heterozygosity (LOH) analysis, we are studying the genetic changes associated with these lesions in archival tissue samples. 50% (6/12) of the proliferative lesions (PDWA and ADH) and 80% of the DCIS shared their LOH patterns with more advanced lesions from the same breast, strongly supporting a precursor/product relationship between these lesions and the cancers they accompany.  相似文献   
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