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71.
72.
Objective : To describe the obstetric and perinatal factors, in particular the method of delivery, associated with development of a subgaleal haematoma (SGH) and to determine the outcome of survivors with this type of birth trauma. Methodology : Perinatal and obstetric data were retrospectively reviewed for 37 infants admitted to the neonatal unit of the sole tertiary paediatric referral hospital in Western Australia with an SGH, over a 24 year period from 1970 to 1993. These data were compared to data for all Western Australian births. The long-term outcome was obtained through medical and private paediatric records for 26 of these infants. Results : All except one of the neonates had instrumental deliveries; 89% had a vacuum extractor applied to the head at some stage of delivery compared to 10% of the general population of births in Western Australia. There was also a significantly increased risk of failure of attempted vacuum extraction. Of the cases where a vacuum extraction was attempted, 45% also had forceps applied to the head. Coagulopathy was associated with the severity of the SGH. There was also a high frequency of occurrence (40%) of associated head trauma such as intracranial haemorrhage, skull fracture and cerebral oedema, as well as neonatal encephalopathy (73%). The occurrence of these associated features did not correlate significantly with the severity of SGH. Minor complications of SGH included jaundice and facial bruising. There was an excess mortality associated with SGH; however, the long-term outcome for neonatal survivors with this disorder was good. None of the cases studied subsequently developed cerebral palsy or intellectual disability, and minor neurological sequelae only were documented in four infants. Conclusions : SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by vacuum extraction. The most commonly associated clinical problems were hypovolaemia and coagulopathy. The long-term outcome for neonates with this condition is good.  相似文献   
73.
Nonstarch polysaccharide consumption in four Scandinavian populations   总被引:1,自引:0,他引:1  
Nonstarch polysaccharide (NSP) intake was measured in representative samples of 30 men aged 50-59 in 2 urban and 2 rural Scandinavian populations that exhibited a 3-4 fold difference in incidence of large bowel cancer. Intake was measured by chemical analysis of complete duplicate portions of all food eaten over one day by each individual. NSP intakes showed a rural-urban gradient, with 18.4 +/- 7.8 g/day in rural Finland and 18.0 +/- 6.4 g/day in rural Denmark versus 14.5 +/- 5.4 g/day in urban Finland and 13.2 +/- 4.8 g/day in urban Denmark. NSP intakes were also calculated (using food tables) from weighed food records kept over 4 days, one of which was the day on which the duplicate collection was made. Intakes were 2-2.5 g/day higher with this method than with direct chemical analysis, mainly because published tables of values have become outdated and inaccurate as a result of improved methods for measuring NSP in food. Individual variation from day to day in NSP intake was considerable. Average NSP intake and intake of some of its component sugars were inversely related to colon cancer incidence in this geographical comparison. To show a relationship at the individual level between diet and cancer risk in a prospective study would require detailed and accurate methods for the assessment of NSP consumption.  相似文献   
74.

Background

Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey.

Methods

Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices). Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire.

Results

5,209 individuals responded with identical rates in both groups (62.1%). Practice, patient age, sex and Townsend score (a postcode based deprivation measure) were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived).

Conclusion

This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire.  相似文献   
75.
Lateral biases in visual perception have been demonstrated in normal individuals and in patients with unilateral brain lesions. It has been suggested that the absence of structural and functional asymmetries in schizophrenia could be due to a failure in lateralisation that may be most pronounced in those patients whose illness onset is at an early age. Here we examined lateral biases in patients with schizophrenia of an early onset (N = 21) and a late onset (N = 19), and their respective age-matched control groups, using the greyscales task, a sensitive measure of asymmetries in visual processing. The stimuli consisted of two rectangles, one above the other, shaded in opposite directions and matched overall for darkness. Participants judged which of the two rectangles looked darker overall. Previous studies using this task in healthy participants have reported a reliable bias, such that the rectangle with the darker end on the left is selected preferentially. Whereas the late-onset patients in this study exhibited a perceptual bias of similar direction and magnitude to that of controls, this was not the case for the early-onset patients, who exhibited significantly less bias than their control group. The reduced perceptual bias seen in the early-onset group, but not the late-onset group, suggests an attenuation of right hemisphere mechanisms dedicated to processing visuospatial information. The attenuated perceptual asymmetry in the early-onset group only may be consistent with the view that (i) an earlier illness onset reflects a greater loss of hemispheric differentiation and (ii) reduced functional asymmetries in the early-onset group are a manifestation of a failure to allocate functions to one or the other hemisphere.  相似文献   
76.
BACKGROUND: It is important to monitor health differentials between population groups to understand how they are generated. Internationally displaced people represent one potentially disadvantaged group. We investigated differentials in mortality between children from former Mozambican refugee and host South African households in a rural sub-district in the north-east of South Africa. METHODS: Open prospective cohort of 30 276 children (80 462 person years of follow-up) followed from 1 January 1992 to 31 October 2000 in Limpopo Province, South Africa. Exposure and outcomes data came from the Agincourt Health and Demographic Surveillance System (DSS). RESULTS: There was no difference in infant mortality between children from former Mozambican refugee households and those from South African homes (adjusted rate ratio [RR] = 1.02, 95% CI: 0.79, 1.32), but mortality levels were higher among former Mozambican refugee children during the next 4 years (adjusted RR = 1.91, 95% CI: 1.50, 2.42). Increased mortality levels were also seen among children from larger households and whose mother died, while children born to mothers aged >40 years or with higher education were at lower risk. Measured maternal, household, and health service utilization characteristics could not explain the difference in mortality between children from former Mozambican refugee and South African households. Former Mozambican refugee children residing in refugee settlements had higher mortality rates than those residing in more established villages. CONCLUSIONS: This study demonstrates higher childhood, but not infant, mortality rates among children from former Mozambican refugee households compared with those from host South African households in rural South Africa. The lack of legal status and lower wealth of many former Mozambican refugees may partly explain this disparity.  相似文献   
77.
AIM: In rural Gambia, birth season predicts infection-related adult mortality. Seasonal factors in early life may programme the immune system, possibly via an effect on thymic development. This study tested whether thymus size in rural Gambian infants is affected by birth season, defined as January-June (harvest, few infections) versus July-December (hungry, high infectious load). METHODS: Thymic volume (thymic index) was assessed sonographically at 1, 8, 24 and 52 wk in 138 singleton infants born over 14 consecutive months. Growth and morbidity were regularly assessed. RESULTS: Mean thymic index increased from 19.9 at 1 wk to 30.9 at 8 wk and 35.7 at 24 wk, then fell to 32.0 at 52 wk. Thymic index was associated with each preceding thymic index up to 24 wk. This tracking persisted after correcting for infant weight and month of measurement (p < 0.01). Thymic index at 1 wk was marginally but non-significantly lower in hungry season births (p = 0.06). Thymic index was lower in hungry season measurements; this effect persisted after adjusting for current weight and infection markers, and was strongest at 8 wk (p = 0.001). CONCLUSION: These results describe a pattern of thymic growth followed by diminution in size. An infant's thymic index tracks despite changes in body weight and season. Thymic index was lower in the hungry season. This appears not to be explained by infection or nutritional status. A possible influence of trophic factors in breast milk merits investigation.  相似文献   
78.
OBJECTIVE: To investigate the effect of the functional CD14 promoter polymorphism on serum liver function tests and abnormally elevated liver function tests in a general population sample. METHODS: We recruited 310 subjects at random from general practitioner lists in Surrey. A previously validated medical questionnaire was completed and a serum sample provided for estimation of liver function test and genotyping of CD14 promoter polymorphism. RESULTS: The TT polymorphism was associated with significantly reduced serum levels of alanine aminotransferase 0.49 (95% confidence interval 0.26-0.93), gamma-glutamyl transferase 0.49 (95% confidence interval 0.38-0.89) and aspartate aminotransferase 0.48 (95% confidence interval 10.38-0.89). The TT polymorphism was associated with a reduced frequency of liver function test abnormalities, especially gamma-glutamyl transferase (odds ratio 0.113; 0.015-0.851). CONCLUSION: The TT promoter polymorphism was associated with reduced serum levels of alanine aminotransferase, gamma-glutamyl transferase and aspartate aminotransferase in healthy patients, and a low level of liver function test abnormalities. The relationship with gamma-glutamyl transferase stands after correction for age, gender, obesity and alcohol consumption. This raises the possibility that this genotype may offer protection from the development of fatty liver disease.  相似文献   
79.
80.
We describe lens defects in heterozygous small eye mice, and autonomous deficiencies of Pax6(+/-) cells in the developing lens of Pax6(+/+) <--> Pax6(+/-) chimeras. Two separate defects of the lens were identified by analyzing the distribution of heterozygous cells in chimeras: Pax6(+/-) cells are less readily incorporated into the lens placode than wild type, and those that are incorporated into the lens are not maintained efficiently in the proliferating lens epithelium. The lens of chimeric eyes is, therefore, predominantly wild type from embryonic day 16.5 onwards, whereas heterozygous cells contribute normally to all other eye tissues. Eye size and defects of the iris and cornea are corrected in fetal and adult chimeras with up to 80% mutant cells. Therefore, these aspects of the phenotype may be secondary consequences of primary defects in the lens, which has clinical relevance for the human aniridia (PAX6(+/-)) phenotype.  相似文献   
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