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1.
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
2.
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
3.
E Harju 《International surgery》1990,75(1):27-35
The findings on dumping syndrome (DS) are not consistent considering its relations with age, sex, weight/height, smoking habits, race, dose of oral glucose, the time elapsed since surgery, the function of exocrine pancreas nor the duration of ulcer symptoms. The patients after total gastrectomy (TG) may present relative postprandial lack of insulin. As a sign of long-term hyperglycemia elevated HbA1 has been measured in DS patients. Oral galactose test may reveal new features of DS. Abnormalities in splanchnic blood circulation as well as release of intestinal hormones are involved with DS. Dietary habits including fibers, pectin and guar gum, play a central role in the prevention and treatment of DS. In unresponsive cases several operative methods have been applied with success. Alkaline reflux gastritis is most often seen after B II and I reconstructions and after pyloroplasty. Chronic diarrhea follows mostly after truncal vagotomy. Ten to 50% of patients after gastrectomy (GE) waste 10 to 20% of their body weight because of decreased food, energy, vitamin and mineral intake caused by eating-related symptoms. Vitamin and mineral supplements, a small snack 20 min before the major meal, digestive enzymes, treatment of colonization with antibiotics and protein foods may help. About 50% of GE patients show iron deficiency anemia. Easily dissolved iron between meals with ascorbic acid give the most effective response. Deficiency of vitamin B12 or of folate may develop as megaloblastic anemia. B12 supplement and antibiotics are effective in bacterial overgrowth, but surgical correction is necessary in troublesome blind loop. Folic acid deficiency is corrected by oral folic acid.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
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.
相似文献
5.
6.
For solid-phase peptide synthesis, 2, 4-dimethoxy-4′ -hydroxybenzhydrol linker was prepared via lithium borohydride reduction of 2, 4-dimethoxy-4′-hydroxybenzophenone. The potassium salt of the linker was coupled to chloromethylpolystyrene. This method proved to be better than use of the cesium salt. This new synthesis gave a polymer with appropriate structure and a good degree of substitution. 相似文献
7.
This case report describes the anaesthetic management of a patient with sporadic-type long QT interval syndrome (LQTS), and increased QT dispersion, who presented for removal of an ovarian cyst. Beta adrenergic blockade and adequate depth of anaesthesia for successful management is emphasized. The Successful use of epidural administration of lignocaine and opioids in addition to general anaesthesia is described. 相似文献
8.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
9.
10.
The nutritional state of 32 patients after (mean 66 months) colon interposition due to benign oesophageal disease was examined. Forty-four per cent of the patients had depleted iron stores (low serum ferritin concentration). Serum iron and blood haemoglobin concentrations were lower (P less than 0.001) in those with low than in those with normal serum ferritin concentration (115 +/- 12 g/l and 15 +/- 5 mumol/l vs 135 +/- 12 g/l and 23 +/- 9 mumol/l). Most very low blood haemoglobin concentrations (less than 110 g/l) were found in patients with depleted iron stores. Eighteen patients had serum albumin concentrations slightly below (35-39 g/l) the normal range, and two other patients had values less than 35 g/l. The patients had less dietary iron (13 +/- 6 mg/d) than age- and sex-matched controls (19 +/- 7 mg/d), but the intake of patients with depleted iron stores (12 +/- 5 mg/d) was similar to that of patients with normal iron stores (14 +/- 6 mg/d). Symptoms and/or the replacement of colon graft anti- or isoperistaltically did not have any significant association with the nutritional status, only slightly reduced blood haemoglobin and serum albumin concentration were found among the symptomatic patients and the patients with an antiperistaltic graft. Iron therapy and protein supplements, eg, from milk, egg, soy and meat, are recommended as the dietary treatment. To improve the nutritional status a short intra-abdominal colon graft loop anastomosed to the proximal stomach instead of long loop with an antral anastomosis of the present patients is suggested. 相似文献