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Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight. 相似文献
4.
M. Pickard E. P. Dewar R. C. Kapadia R. B. N. Khan I. F. Hutchinson A. Nejim 《Colorectal disease》2007,9(3):203-206
OBJECTIVE: The publication of the BSG guidelines in 2002 provided a framework for the follow up of patients with colorectal polyps. The aim of the present study was to determine whether they had, or were being correctly adhered to in a moderately sized District General Hospital. METHOD: A total of 598 patients were on the waiting list for colonoscopy at Airedale General Hospital (AGH) in February 2005. Of these, 203 were being followed up as a result of the previous finding of a polyp. RESULTS: Only 14.8% of patients had been or were being followed up according to the BSG guidelines. The majority of the 85.2% of patients who did not comply with follow up did so as a result of over investigation. Seventy-eight per cent of the low-risk group and 55% of the intermediate-risk group had been colonoscoped, or were waiting to have colonoscopy, too soon or too frequently according to the BSG guidelines. Twenty-four patients with hyperplastic polyps were being followed up incorrectly, as were 17 patients discovered to have a polyp pathology on flexible sigmoidoscopy. It was established that 131 extra colonoscopies had been, or were planned to be performed unnecessarily. CONCLUSION: These data have major implications with regard to patient safety, service provision and cost to the NHS. 相似文献
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Michael Hutchinson Jonathon O'Riordan Mohammed Javed Etain Quin Donal Macerlaine Teresa Willcox Nollaig Parfrey Tamas G. Nagy Elisabeth Tournier-Lasserve 《Annals of neurology》1995,38(5):817-824
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently described familial cerebrovascular disorder shown to map to chromosome 19q12. Familial hemiplegic migraine has also been shown in some families to map close to the CADASIL locus. The fully developed CADASIL phenotype consists of recurrent strokes developing in the fourth decade, progressing to a pseudobulbar palsy, spastic quadriparesis, and subcortical dementia. In an Irish family 15 members were fully investigated by magnetic resonance scanning; 10 had typical magnetic resonance features of CADASIL. Five members of this family had familial hemiplegic migraine and 4 of these had magnetic resonance evidence of CADASIL. Two other members had migraine with and without aura as a presenting clinical symptom of CADASIL. This disorder has been shown by linkage analysis to map to the CADASIL locus at chromosome 19. The phenotype at presentation of CADASIL in this family was variable and age related and included familial hemiplegic migraine, migraine with and without aura, transient ischemic attacks, strokes, and spinal cord infarction. This family study increases our understanding of the spectrum of clinical manifestations of this underrecognized familial cerebrovascular disorder. 相似文献
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The Stafford outbreak of Legionnaires' disease 总被引:1,自引:0,他引:1
M C O'Mahony R E Stanwell-Smith H E Tillett D Harper J G Hutchison I D Farrell D N Hutchinson J V Lee P J Dennis H V Duggal 《Epidemiology and infection》1990,104(3):361-380
A large outbreak of Legionnaires' disease was associated with Stafford District General Hospital. A total of 68 confirmed cases was treated in hospital and 22 of these patients died. A further 35 patients, 14 of whom were treated at home, were suspected cases of Legionnaires' disease. All these patients had visited the hospital during April 1985. Epidemiological investigations demonstrated that there had been a high risk of acquiring the disease in the out patient department (OPD), but no risk in other parts of the hospital. The epidemic strain of Legionella pneumophila, serogroup 1, subgroup Pontiac 1a was isolated from the cooling water system of one of the air conditioning plants. This plant served several departments of the hospital including the OPD. The water in the cooling tower and a chiller unit which cooled the air entering the OPD were contaminated with legionellae. Bacteriological and engineering investigations showed how the chiller unit could have been contaminated and how an aerosol containing legionellae could have been generated in the U-trap below the chiller unit. These results, together with the epidemiological evidence, suggest that the chiller unit was most likely to have been the major source of the outbreak. Nearly one third of hospital staff had legionella antibodies. These staff were likely to have worked in areas of the hospital ventilated by the contaminated air conditioning plant, but not necessarily the OPD. There was evidence that a small proportion of these staff had a mild legionellosis and that these 'influenza-like' illnesses had been spread over a 5-month period. A possible explanation of this finding is that small amounts of aerosol from cooling tower sources could have entered the air-intake and been distributed throughout the areas of the hospital served by this ventilation system. Legionellae, subsequently found to be of the epidemic strain, had been found in the cooling tower pond in November 1984 and thus it is possible that staff were exposed to low doses of contaminated aerosol over several months. Control measures are described, but it was later apparent that the outbreak had ended before these interventions were introduced. The investigations revealed faults in the design of the ventilation system. 相似文献
8.
P.F. MORSE D.F. HORROBIN M.S. MANKU J.C.M. STEWART R. ALLEN S. LITTLEWOOD S. WRIGHT† J. BURTON† D.J. GOULD‡ P.J. HOLT§ C.T. JANSEN¶ L. MATTILA¶ W. MEIGEL TH. DETTKE D. WEXLER†† L. GUENTHER†† A. BORDONI‡‡ A. PATRIZI‡‡ 《The British journal of dermatology》1989,121(1):75-90
Gamma-linolenic acid in the form of a particular variety of evening primrose oil (Epogam) has been reported of value in the treatment of atopic eczema. Nine controlled trials of evening primrose oil were performed in eight centres. Four of the trials were parallel and five cross-over. Doctors and patients assessed the severity of eczema by scoring measures of inflammation, dryness, scaliness, pruritus and overall skin involvement. Individual symptom scores were combined to give a single global score at each assessment point. In the analysis of the parallel studies, both patient and doctor scores showed a highly significant improvement over baseline (P less than 0.0001) due to Epogam: for both scores the effect of Epogam was significantly better than placebo. Similar results were obtained on analysis of the cross-over trials, but in this case the difference between Epogam and placebo in the doctors' global score, although in favour of Epogam, failed to reach significance. The effects on itch were particularly striking. There was no placebo response to this symptom, whereas there was a substantial and highly significant response to Epogam (P less than 0.0001). When the improvements, or otherwise, in clinical condition were related to changes in plasma levels of dihomogammalinolenic and arachidoni acids, it was found that there was a positive correlation between an improvement in clinical score and a rise in the fatty acid levels. 相似文献
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Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit
the determination of femtogram amounts of 26Al in blood and in various
tissues with good precision and free of external contamination. METHODS: In
the present study we used trace quantities of 26Al to investigate the
intestinal absorption and compartmentalization of aluminium in rats with
renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single
oral doses of 20 ng 26Al were administered to six animals in each group
and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone,
liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al
were significantly lower in uraemic rats compared to controls, whereas
urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/-
6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in
uraemia. The target tissues of cellular transferrin-mediated 26Al uptake,
liver and spleen, tended to show a larger degree of aluminium accumulation
in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27
pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site
of extracellular aluminium deposition, 26Al concentrations were more
elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g).
Estimated total 26Al accumulation in all measured target tissues was
significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/-
7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/-
6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a
fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our
data suggest that fractional absorption from a dietary level dose of 26Al
is about 0.13%. Compartmentalization occurs in transferrin-dependent target
tissues such as liver and spleen; however, in quantitative terms
extracellular deposition in bone is more important. Uraemia has a
significant effect on the intestinal absorption and compartmentalization of
aluminium. It enhances fractional absorption and increases subsequent
extracellular deposition of aluminium in bone. However, at the same time
uraemia does not increase transferrin-dependent cellular accumulation of
aluminium in liver and spleen.
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