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Transcapillary escape rate of albumin was determined in 22 patients with different malignancies. In addition, urinary albumin excretion rate was measured in 24-h urine samples using a sensitive immunoassay. Increased urinary albumin excretion was defined as ≥20 μg/min according to conventional standards. Renal glomerular filtration and tubular function was estimated by51Cr-EDTA plasma clearance and urinary beta 2-microglobulin, respectively. Median urinary albumin excretion rate was 15.0 μg/min (range 6–510 μg/min) and the frequency of increased urinary albumin excretion was 41%. This agrees with other studies showing increased albuminuria in several types of malignant diseases. Patients with advanced disease (tumour, node, metastasis (TNM) stage II–IV) had a significantly higher urinary albumin excretion rate than patients with localized disease (TNM stage I). Serum creatinine, glomerular filtration rate and urinary beta 2-microglobulin were all within normal limits. Median transcapillary escape rate of albumin was 5.5%/h (range 2–8%/h) and this level is comparable with values in healthy subjects. There was no significant difference in transcapillary escape rate between patients with elevated urinary albumin excretion and the normoalbuminuric group. Median value of the absolut outflux of albumin was 10.6 g/h with similar levels in patients with increased urinary albumin excretion and patients with normoalbuminuria. Our results indicate a high prevalence of minor glomerular dysfunction with a slightly elevated urinary albumin excretion in patients with malignancies. The normal endothelial function, as estimated by the transcapillary escape rate of albumin, suggests an overal unaffected capillary permeability and increased urinary albumin loss appears to be an isolated renal phenomenon in cancer patients.  相似文献   
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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   
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The purpose of this study was to assess the selenium status of a well-defined industrially employed population: eighty-six oil refinery workers. Plasma selenium levels and erythrocyte GSH-Px activities were significantly lower in this industrial group (86 subjects) than in non-industrial group (174 subjects). In order to evaluate whether these lower values were responsive to supplementation, ten subjects from the industrial group were further studied for 12 weeks. Five of these subjects consumed a selenium supplement, 50 μg Se as sodium selenite, once a day for eight weeks (weeks 2 to 10 of study). Diet histories revealed that these 10 workers consumed an average of 217±73 μg Se/day indicating that they were consuming selenium levels above the recommendations of the Food and Nutrition Board of the NRC. The supplemented group had significantly higher whole blood selenium levels and GSH-Px activity than the non-supplemented group and this difference was due to a drop in the levels found in the non-supplemented group at weeks 8 and 10. These data suggest that selenium supplementation prevented the decreases in blood selenium levels and GSH-Px activity experienced by the non-supplemented subjects. Also, there was a positive correlation between blood selenium levels and GSH-Px (r=0.45, p<0.001). Thus, these oil refinery workers maintained GSH-Px activity only when consuming a selenium supplement suggesting that these workers may have a higher selenium need than any previously studied populations.  相似文献   
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This work represents the first application of a statistical mechanics based microstructural orthotropic hyperelastic model to pulmonary artery mechanics under normotensive and hypertensive conditions. The model provides an analogy between the entangled network of long molecular chains and the structural protein framework seen in the medial layer, and relates the mechanical response at macro-level to the deformation (entropy change) of individual molecular chains at the micro-level. A finite element approach was adopted to implement the model. Material parameters were determined via comparing model output to measured pressure–stretch results from normotensive and hypertensive trunks and branches obtained from a rat model of pulmonary arterial hypertension. Results from this initial study show that this model appears reasonable for the study of hyperelastic and anisotropic pulmonary artery mechanics. Typical tangent modulus values ranged from 200 to 800 kPa for normotensive arteries—this increased to beyond 1 MPa for hypertensive vessels. Our study also provokes the hypothesis that increase of cross-linking density may be one mechanism by which the pulmonary artery stiffens in hypertension.  相似文献   
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BACKGROUND: There are significant differences in mean birthweights between New Zealand's main ethnic groups. Birthweight centiles developed predominantly from babies of European ethnicity may therefore not be appropriate to classify babies from other ethnic groups. AIMS: To develop ethnic specific birthweight centiles for New Zealand babies delivered at term (>37 weeks). METHODS: Births from the National Women's Hospital database from 1993 to 2000 who also had scan data at <24 weeks comprised the study population (n = 10 292). Multiple pregnancies, fetal abnormalities, stillbirths and preterm births were excluded. For six ethnic groupings, born at gestational weeks from 38 to 41, sex specific centiles were generated and smoothed. RESULTS: Birthweight centiles were constructed from 5203 European, 801 Maori, 825 Samoan, 577 Tongan, 1058 Chinese, 433 Indian and 1395 other ethnic group births. Mean birthweights by ethnic group were: European 3521 g, Maori 3467 g, Samoan 3691 g, Tongan 3791 g, Chinese 3418 g, Indian 3192 g and other 3466 g. Tongan and Samoan babies were significantly heavier and Indian babies were significantly lighter than babies from all other ethnic groups (P < 0.001 for all comparisons). Overall Maori babies were approximately 50 g lighter than European babies but this difference was not statistically significant (P = 0.08), whereas Chinese babies were significantly lighter with a mean birthweight 100 g less than European (P < 0.001). CONCLUSIONS: These ethnic specific centile charts are likely to identify term babies with inappropriate growth better than population centiles generated predominantly from one ethnic group.  相似文献   
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AIMS: To review the demographic characteristics, antecedents and outcome for early neonatal Escherichia coli sepsis. Secondary aims were to identify antenatal antibiotic use and to review the antimicrobial susceptibility. METHODS: A retrospective chart review was performed for all infants with a positive culture for E. coli from either blood or CSF samples obtained between January 1998 and October 2002. RESULTS: Nineteen liveborn infants with early onset sepsis and one stillborn baby with a positive maternal blood culture for E. coli were identified. Pregnancy complications included multiple pregnancy in five (25%), preterm rupture of membranes 10 (50%) and maternal urinary tract infection in five (25%). Eighteen of the cases were born preterm and two at term. The mortality was 8/20 (40%), and for nine cases with developmental outcome data available, 67% were within normal limits and 33% were abnormal. Of the 20 E. coli isolates 11 (55%) were resistant to amoxycillin and 1 (5%) was resistant to gentamicin. CONCLUSIONS: Infants with early onset E. coli sepsis had a poor outcome with high mortality and a third of the survivors manifesting neurodevelopmental impairment. Although amoxycillin resistance is common, there is a low prevalence of gentamicin resistance in local isolates.  相似文献   
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