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991.
992.
The events that led to the publication in English of this important nutrition policy document provide an excellent example of how delightful things sometimes happen largely because of coincidence, and because strangers quickly become friends when they discover common interests.  相似文献   
993.
To determine the prevalence of developmental dysplasia of the hip (DDH) in South Australia (SA) in 1991, the proportion of cases detected in the neonatal period and the perinatal risk factors for DDH.

Methodology:


Cases of DDH born in SA in 1991 were identified from multiple sources and their clinical data linked to perinatal data provided by midwives; five controls per case were obtained randomly from SA livebirths without congenital abnormalities and adjusted odds ratios (OR) for potential risk factors obtained by logistic regression analysis. South Australia perinatal data were also used to estimate numbers of births with perinatal risk factors for targeted screening.

Results:


Two hundred and six cases of isolated DDH were identified, giving a prevalence of 10.5 per 1000 births. Of these, 173 (84%) had been detected in the neonatal period. The perinatal risk factors for DDH were identified as breech presentation (OR 9.65), female babies (OR 4.04), first births (OR 1.91) and maternal age of 25 years or more (OR 1.53). Screening breech and firstborn female babies (23% of births) would yield approximately 51% of cases of DDH.

Conclusions:


Isolated DDH had a prevalence of 10.5 per 1000 births and 84% of cases had been detected in the neonatal period in SA. Repeated screening during infancy of 'at risk' groups of babies is recommended.  相似文献   
994.
995.
996.
Objective: To identify potentially preventable risk factors for sensorineural hearing loss (SNHL) in extremely premature infants.
Methodology A case control study of survivors with gestational age (GA) <28 weeks or birthweight (BW) <1000 g using data collected prospectively in our Neonatal Intensive Care Unit database. Each subject with bilateral SNHL >40dB was matched according to GA, BW and sex with two controls who had neither sensorineural nor conductive hearing loss.
Results Infants with SNHL had increased mean (±s.d.) days ventilated (53 ± 21 vs 37±23 days, P = 0.006) and in oxygen (107±44 vs 69±28 days, P = 0.02) compared with controls. The risk for SNHL was increased for infants who spent >90 days in oxygen (OR 4.0 [95% Cl 1.1-15.6]), had maximum FiO2 >0.90 (5.6 [1.2-26.9]), minimum plasma Na <125mmol/L (5.6 [1.1-27.8] or maximum pH >7.60 (5.6 [1.1-89.0]). Neither maximum serum bilirubin nor exposure to ototoxic drugs was associated with SNHL.
Conclusions: Avoidance of severe hyponatraemia and extreme alkalosis, as well as use of surfactant to minimize the severity of hyaline membrane disease, may result in a decreased incidence of SNHL in extremely premature infants.  相似文献   
997.
The hereditary pancreatitis gene maps to long arm of chromosome 7   总被引:11,自引:0,他引:11  
Hereditary pancreatitis (HP) is an autosomal dominant disorder with incomplete penetrance characterized by recurring episodes of severe abdominal pain often presenting in childhood. Although this disorder has only been recently described, about 100 families have been documented worldwide. The pathophysiology of this disorder is unknown. Here, a large French family of 147 individuals (47 of whom were affected) from a four-generation kindred with HP has been examined and a genome segregation analysis of highly informative microsatellite markers has been performed. Linkage has been found between HP and six chromosome 7q markers. Maximal two point lod scores between HP and D7S 640, D7S 495, D7S 684, D7S 661, D7S 676 and D7S 688 were 4.00 (theta = 0.143), 5.85 (theta = 0.143), 4.91 (theta = 0.156), 8.58 (theta = 0.077), 8.28 (theta = 0.060), 4.40 (theta = 0.169), respectively. Multipoint linkage data combined with recombinant haplotype analysis indicated that the most likely order is: D7S 640-D7S 495-D7S 684-D7S 661-D7S 676-D7S 688, with the HP gene situated in the underlined region. As in all families reported in the literature, the clinical presentation of the disease is identical to the presentation of sporadic cases, one could expect that the knowledge of the HP gene could be a clue to pancreatitis in general. Based on its map position, this is the first step towards the positional cloning of the Hereditary Pancreatitis Gene (HPG).   相似文献   
998.
CpG dinucleotides provide hotspots for transitional mutations in a variety of genes, some leading to genetic diseases in humans. Although this phenomenon is attributed to cytosine methylation at such sites, direct and specific observations of CpG methylation at the sites of recurrent mutations are lacking. We have used a bisulfite genomic sequencing method to analyze DNA methylation within three representative exons from the neurofibromatosis type 1 (NF1) gene, well recognized for its high frequency of spontaneous mutations. We observed that the cytosine methylation within NF1 exons 28, 29, and 31 is restricted to CpG dinucleotides, including the CpG dinucleotide present at the site of the recurrent NF1 mutation (C5839T; also referred to as R1947X). At several sites, clone-specific methylation differences were also observed. Our results provide experimental evidence for the hypothesis that methylatable CpGs in the NF1 gene contribute to spontaneous germline mutations associated with this gene, by showing that DNA methylation does occur at all CpGs contained within these representative NF1 exons. As well, the DNA methylation seen at the common mutation site in exon 31 may explain why this site is frequently mutated. Methylation-dependent mutagenesis may also provide a basis for some somatic (second hit) mutations which disable the normal allele and result in the development of NF1 associated symptoms.   相似文献   
999.
The objective of this study was to assess the safety and to make a preliminary assessment of the efficacy of 0.5% ferric hyaluronate adhesion prevention gel in reducing adhesions in patients undergoing peritoneal cavity surgery by laparotomy, with a planned 'second-look' laparoscopy. The study was a randomized, open-label, placebo- controlled, parallel-group design in patients desirous of fertility at the Women's and Children's Hospital, Department of Obstetrics and Gynecology, University of Southern California School of Medicine, Los Angeles, California. Female patients aged 24 to 41 years received 300 ml 0.5% ferric hyaluronate adhesion prevention gel or lactated Ringer's solution as an intraperitoneal instillate at the completion of the laparotomy procedure. At second-look laparoscopy 4-12 weeks after the laparotomy, the presence of adhesions was evaluated. Haematology and serum chemistry were determined throughout the study interval. All patients tolerated the procedures well and did not manifest any serious adverse events. At second-look laparoscopy, patients treated with 0.5% ferric hyaluronate adhesion prevention gel had significantly fewer adhesions than control patients. When adhesions did form, they were significantly less extensive and less severe in patients who received 0.5% ferric hyaluronate adhesion prevention gel. In conclusion, 0.5% ferric hyaluronate adhesion prevention gel was safe and highly efficacious in the reduction of the number, severity and extent of adhesions throughout the entire abdomen following peritoneal cavity surgery.   相似文献   
1000.
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