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1.
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
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Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.  相似文献   
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In a community sample of 2,327 Caucasians, we tested the hypotheses that polymorphisms in the COMT and DRD3 genes are associated with personality traits conferring vulnerability to anxiety, depression, or alcohol misuse, or with current symptoms of these; and that the association is stronger in persons who also have been exposed to stressor experiences. To conserve resources and to allow replication, the genetic analysis was undertaken in two stages. For the COMT polymorphism, no statistically significant associations were found in the first sample of 862 persons. The remainder of the sample was therefore not analysed for that gene. For the DRD3 polymorphism, those in the first sample with at least one of the Ser(9) alleles had significantly higher scores in neuroticism (p=0.006) and behavioral inhibition (p=0.003). There was a trend, failing to meet the 1% significance criterion, for those with this genotype also to have higher depression and anxiety. The groups did not differ in alcohol use. In persons with the Ser(9) allele who were also exposed to stressors, there was a higher level of depression at the 5% level; and the depression level was higher in homozygotes. But when the remainder of the sample (1,465) was analysed, none of the associations reached statistical significance. We conclude that neither the COMT nor DRD3 polymorphisms are associated with anxiety, depression, or alcohol abuse. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:102-107, 2000 Copyright 2000 Wiley-Liss, Inc.  相似文献   
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It is still unclear whether i.v. immunoglobulins (Ig) can facilitate the reproductive prognosis of women who have suffered recurrent pregnancy loss. We report the results of a multicentre placebo- controlled study on the effect of Ig administration on pregnancy outcome in 46 women who had suffered at least three recurrent miscarriages. All were screened to exclude chromosomal or Mullerian abnormalities, the presence of antinuclear antibodies, lupus anticoagulant (LA) or elevated titres of anticardiolipin antibodies which may have revealed an underlying autoimmune problem. To avoid a selection bias towards ongoing pregnancies, i.v. Ig or placebo were administered between weeks 5 and 7 of gestation for 2 consecutive days as soon as each woman knew she was pregnant and before embryonic heart activity could be detected. A further infusion was administered at week 8 when ultrasonography confirmed an ongoing embryonic development. In all, 68% of the women who received Ig went to term versus 79% of those who received a placebo (not significant), with no significant differences in the pregnancy course or the perinatal outcome. These results suggest either that women with recurrent miscarriages who have no recognized cause of pregnancy loss have a good reproductive prognosis without any treatment or that the emotional care associated with the administration of a placebo can indirectly facilitate the progression of pregnancy.   相似文献   
6.
OBJECTIVE: This study examines the factorial structure of symptoms and signs in psychosis in data from the Study on Low Prevalence (psychotic) Disorders which is part of the National Survey of Mental Health and Wellbeing, Australia 1997-1998. METHOD: The present study examined a wide variety of symptoms taken from the Schedules for Clinical Assessment in Neuropsychiatry items and the substance use items in the Diagnostic Interview for Psychosis, an instrument specially constructed for the national study. The instrument was applied to 980 community and hospital subjects with a wide range of psychotic illness diagnoses. The data were factor analysed and scales of 'domains of psychopathology' derived. RESULTS: The data were best fitted by five principal factors ('domains') which can be approximately labelled dysphoria, positive symptoms, substance use, mania and negative symptoms/incoherence. These factors together explained 55.4% of variance in symptoms. Solutions with more numerous factors did not improve the representation. CONCLUSION: The five domains successfully characterise a large part of the variance in psychopathology found in the present study of low prevalence (psychotic) disorders. The approach allows sufferer's symptom range and severity to be well expressed without multiple comorbid diagnoses or the limits imposed by categorical diagnosis. Knowledge of alternative dimensional representations of psychopathology may usefully complement our use of categories, enhance awareness of symptoms and ensure that important psychopathology is heeded in practice and research.  相似文献   
7.
Background: Previous research has found that there are major differences between public and professional beliefs about the helpfulness of interventions for depression. The public appear to be guided by general belief systems about the helpfulness of medical, psychological and lifestyle interventions rather than by specific knowledge about what interventions are effective for depression. The present paper examines the effect that experiencing depression and receiving treatment might have on these beliefs. Method: The study involved a postal survey of 3109 adults from a region of New South Wales, Australia. Respondents were presented with a vignette describing a person with depression. They were asked to rate the likely helpfulness of various types of professional and non-professional help and of pharmacological and non-pharmacological interventions for the person described in the vignette. Respondents also completed the Goldberg Depression Scale and were asked whether they had ever had an episode of depression and whether they had seen a counsellor or a doctor for it at the time. Structural equation modelling was used to investigate the associations of history of depression and professional help-seeking with belief systems. Results: A three-factor model was found to fit the helpfulness ratings, with factors reflecting beliefs in medical, psychological and lifestyle interventions. People who had sought help for depression were less likely to believe in the helpfulness of lifestyle interventions and more likely to believe in medical interventions. As well as these general associations with belief systems, having sought help for depression had a number of specific associations with beliefs. Controlling for general belief systems, those who had sought help were more likely to rate antidepressants, holidays, massage and new recreational pursuits as helpful, and were less likely to rate ECT and family as helpful. Those who had a history of depression but had not sought help were more likely to rate counselling as helpful, and less likely to rate family as helpful. Those with current depressive symptoms were less likely to rate telephone counselling, family and friends as helpful. Conclusion: Having sought help for depression is associated with general belief systems about the helpfulness of lifestyle and medical interventions and also has some associations with specific beliefs that may reflect experiences with treatment (e.g. the helpfulness of antidepressants). Those currently depressed or with a history of depression are less likely to regard family as helpful, possibly due to poorer social support. Generally speaking, having sought help is associated with beliefs closer to those of professionals. Accepted: 31 January 2000  相似文献   
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Liver hemangioma: US-guided 18-gauge core-needle biopsy   总被引:6,自引:0,他引:6  
Heilo  A; Stenwig  AE 《Radiology》1997,204(3):719
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