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101.
OBJECTIVES: We sought to determine the importance of chest pain on presentation as a predictor of in-hospital treatment and mortality in myocardial infarction (MI) patients with left bundle-branch block (LBBB). BACKGROUND: Left bundle-branch block patients have a high mortality after MI but are unlikely to receive reperfusion therapy despite evidence from clinical trials demonstrating the efficacy of thrombolytic therapy. Nearly half of MI patients with LBBB present without chest pain. METHODS: We studied the clinical features, treatment and in-hospital survival of 29,585 patients with LBBB enrolled in the National Registry of MI 2 June 1994 through March 1998). Multivariate logistic regression was used to assess the independent effect of chest pain on reperfusion decisions and in-hospital mortality. RESULTS: Left bundle-branch block patients with chest pain were greater than five-fold more likely to receive reperfusion therapy (13.6% vs. 2.6%) than LBBB patients without chest pain; they were also more likely to receive aspirin, beta-adrenergic blocking agents, heparin and nitrates (all p < 0.0001). Unadjusted in-hospital mortality was 18% in patients with chest pain and 27% in patients without chest pain. Adjusting for patient characteristics reduced the odds ratio associated with the absence of chest pain from 1.47 (95% confidence interval: 1.41 to 1.54) to 1.21 (95% confidence interval: 1.12 to 1.30). The remainder of the mortality difference was caused by the undertreatment of patients without chest pain, particularly the low utilization of aspirin and beta-blockers. CONCLUSIONS: Left bundle-branch block patients with MI who present without chest pain are less likely to receive optimal therapy and are at increased risk of death. Prompt recognition and treatment of this high-risk subgroup should improve survival.  相似文献   
102.
Neonatal pneumopericardium is usually a complication of mechanical ventilation in premature infants with respiratory distress syndrome. We report a full-term neonate who developed pneumopericardium after forceps delivery and mild asphyxia. The child was never ventilated and had no signs of parenchymal lung disease. The pneumopericardium resolved spontaneously. Although drainage of pneumopericardium is usually recommended, this may not always be necessary when there are no signs of cardiac tamponade.  相似文献   
103.
Microdysgenesis is a microscopic malformation of cortical development (MCD) associated with epilepsy, but its significance in epileptogenesis is debated. This is partly since the histopathological aberrations associated with microdysgenesis can also be found in normal brains. We here report a method for objective analysis of one criterion for microdysgenesis, irregular cortical nerve cell distribution. Tissue from the lateral temporal lobe from two epilepsy patients was compared with tissue from two post-mortem controls. An expansion/shrinkage factor was calculated to determine the change in tissue size during cutting and mounting. Neurons were identified and the positions of their nucleoli were marked and stored. The spatial distribution of neurons was analysed using distance to nearest neighbouring neuron and Voronoi tessellation. Specimens from the epilepsy patients expanded markedly during mounting compared with controls. Epilepsy specimens had shorter mean distances to nearest neighbour than controls and smaller Voronoi tessellation areas than controls. Both measurements suggest more densely packed neurons in epilepsy specimens. This pilot study describes a new objective method for identification of cortical neurons and their spatial distribution. Voronoi tessellation and distance to nearest neighbouring neuron might provide robust methods for objective analysis of cortical nerve cell distribution. The yield of such comparisons might be improved if each cortical layer is analysed separately.  相似文献   
104.
105.
BACKGROUND: Iron supplements are often recommended for older breast-fed infants, but little is known about factors affecting iron absorption from human milk or supplements. OBJECTIVE: We investigated the effects of age, iron status, and iron intake on iron absorption in healthy, term, breast-fed infants. DESIGN: Twenty-five infants were randomly assigned to receive either 1) iron supplements (1 mg x kg(-1) x d(-1)) from 4 to 9 mo of age, 2) placebo from 4 to 6 mo and iron supplements from 6 to 9 mo, or 3) placebo from 4 to 9 mo. Infants were exclusively breast-fed to 6 mo and partially breast-fed to 9 mo of age. Iron absorption was assessed by giving (58)Fe with mother's milk at 6 and 9 mo. Blood samples were obtained at 4, 6, and 9 mo, and complementary food intake was recorded at 9 mo. RESULTS: At 6 mo, mean (+/-SD) fractional iron absorption from human milk was relatively low (16.4 +/- 11.4%), with no significant difference between iron-supplemented and unsupplemented infants. At 9 mo, iron absorption from human milk remained low in iron-supplemented infants (16.9 +/- 9.3%) but was higher (P = 0.01) in unsupplemented infants (36.7 +/- 18.9%). Unexpectedly, iron absorption at 9 mo was not correlated with iron status but was significantly correlated with intake of dietary iron, including supplemental iron. CONCLUSIONS: Changes in the regulation of iron absorption between 6 and 9 mo enhance the infant's ability to adapt to a low-iron diet and provide a mechanism by which some, but not all, infants avoid iron deficiency despite low iron intakes in late infancy.  相似文献   
106.
Breast-feeding protects against celiac disease   总被引:1,自引:0,他引:1  
BACKGROUND: Celiac disease, or permanent gluten-sensitive enteropathy, is an immunologic disease strictly dependent on exposure to wheat gluten or related proteins in rye and barley. OBJECTIVE: The aim of this study was to explore whether breast-feeding and the mode of introducing dietary gluten influence the risk of celiac disease in childhood. DESIGN: A population-based incident case-referent study of Swedish children, 627 cases with celiac disease and 1254 referents, was conducted; 78% of the matched sets were included in the final analyses. A questionnaire was used to assess patterns of food introduction to infants. Models were built, based on current epidemiologic and immunologic knowledge of celiac disease, to study the potential influence of dietary patterns on disease risk and were evaluated by conditional logistic regression in multivariate analyses. RESULTS: The risk of celiac disease was reduced in children aged <2 y if they were still being breast-fed when dietary gluten was introduced [adjusted odds ratio (OR): 0.59; 95% CI: 0.42, 0.83]. This effect was even more pronounced in infants who continued to be breast-fed after dietary gluten was introduced (OR: 0.36; 95% CI: 0.26, 0.51). The risk was greater when gluten was introduced in the diet in large amounts (OR: 1.5; 95% CI: 1.1, 2.1) than when introduced in small or medium amounts. In older children, these risk factors were of no or only minor importance. CONCLUSIONS: The gradual introduction of gluten-containing foods into the diet of infants while they are still being breast-fed reduces the risk of celiac disease in early childhood and probably also during the subsequent childhood period.  相似文献   
107.
BACKGROUND: The appropriate level of iron fortification in infant formula remains undetermined. OBJECTIVES: We compared hematologic indexes and iron-status indicators in infants who were either breast-fed or fed formula with concentrations of 2 or 4 mg Fe/L and evaluated the effects of providing part of the iron as bovine lactoferrin and of adding nucleotides. DESIGN: Healthy term infants were exclusively breast-fed (n = 16) or fed formula (n = 10-12) from age 4 +/- 2 wk to 6 mo. Anthropometric measures were taken monthly, and blood samples were taken at 1, 4, and 6 mo. Hematologic indexes; indicators of iron, zinc, and copper status; and erythrocyte fatty acids were assessed. RESULTS: No significant differences in hematology or iron status were observed between groups at 4 and 6 mo of age. Although 34% of all infants had a hemoglobin concentration <110 g/L at 6 mo, the absence of iron deficiency or defective erythropoiesis suggests that this hemoglobin cutoff is too high for this age group. Neither the source or the concentration of iron in formula nor fortification with nucleotides had any significant effect on serum zinc or copper, and nucleotide fortification did not affect erythrocyte fatty acids. CONCLUSIONS: A concentration of 1.6 mg Fe/L formula meets the iron requirement of healthy term infants aged 相似文献   
108.
Insulin resistance develops as a response to virtually all types of surgical stress. There is an increasing body of evidence that suggests that insulin resistance in surgical stress is not beneficial for outcome. A recent large study in intensive-care patients showed that aggressive treatment of insulin resistance using intravenous insulin reduced mortality and morbidity substantially. Similarly, in burn patients, intensive insulin and glucose treatment has been shown to improve N economy and enhance skin-graft healing. In surgical patients insulin resistance has been characterized in some detail, and has been shown to have many similarities with metabolic changes seen in patients with type 2 diabetes. This finding may be important since insulin resistance has been shown to be one independent factor that influences length of stay. When patients about to undergo elective surgery have been treated with glucose intravenously or a carbohydrate-rich drink instead of overnight fasting, insulin resistance was reduced by about half. A small meta-analysis showed that when post-operative insulin resistance was reduced by pre-operative carbohydrates, length of hospital stay was shortened. Overnight intravenous glucose at high doses improved post-operative N economy. This type of treatment has also been shown repeatedly to reduce cardiac complications after open-heart surgery. Furthermore, if the carbohydrates are given as a drink pre-operatively, pre-operative thirst, hunger and anxiety are markedly reduced. In summary, preventing or treating insulin resistance in surgical stress influences outcome. Fasting overnight is not an optimal way to prepare patients for elective surgery. Instead, pre-operative carbohydrates have clinical benefits.  相似文献   
109.
BACKGROUND: As a part of the Vadstena Osteoporosis Prevention Project, the knowledge of osteoporosis was examined before the intervention program started, after 5 and 10 years. METHODS: At baseline (in 1989) 15% of the population in two Swedish municipalities was randomly invited to the study. The participants in the study group were invited for examination by forearm bone densitometry and a questionnaire concerning lifestyle and risk factors for osteoporosis and also knowledge of osteoporosis, while the subjects in the control group were examined only by questionnaire. Follow-ups were made in 1994 and in 1999. Meanwhile education about osteoporosis was given to the study group, to the public, and to various professionals in the study community. RESULTS: There was a difference in the level of knowledge between the groups prior to the intervention. The rate of increment did not differ significantly between the groups for the study period. Previous participants had 0.58 higher score than new participants in the study group in 1994 (P = 0.031) and 0.76 higher score in 1999 (P < 0.001) regarding the total number of correct answers. The women in the study group had 0.63 higher score than the men in 1994 (P = 0.016) and 1.03 higher score in 1999 (P < 0.001) regarding the total number of correct answers. CONCLUSION: There was no significant effect of a general intervention program concerning the knowledge of osteoporosis in participants in the intervention area compared to the control area.  相似文献   
110.
OBJECTIVES: This study investigated the possibility of occupational exposure to ozone increasing the risk of obstructive airway disease among bleachery workers. : Bleachery workers (N = 129) from two Swedish pulp mills using ozone for bleaching were studied together with referents (N = 80) from adjacent paper mills. The pulp mills had previously used chlorine dioxide as the bleaching agent. Testings included spirometry, methacholine challenge testing, and questionnaires. Area samplings showed sporadic ozone levels exceeding 0.9 ppm. RESULTS: There was a greater prevalence of wheezing (25%) among the bleachery workers with a history of gassings (from ozone, chlorine, or sulfur dioxide) than among those without gassings (18%) and among the referents (13%). Among the current smokers the fraction with a slightly increased bronchial responsiveness to methacholine was greater among the bleachery workers reporting gassings than among those that had not been gassed. For the period from 1992 to 1996, when the mills were using ozone, there was an increased incidence rate of wheezing among the workers in the bleachery (incidence rate ratio 2.3, 95% confidence interval 1.6-5.8). CONCLUSIONS: Repeated exposure to irritants increases the risk of asthma-like symptoms. This finding reinforces the view that repeated peak exposures to irritants must be prevented in pulp mills.  相似文献   
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