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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.
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
4.
5.
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
6.
7.
Treatment with combined IL-2 and alpha-IFN has resulted in synergistic antitumour efficacy in animal studies. The mechanisms responsible for this synergy remain unclear. In this study, several immune parameters which might be involved in mediating antitumour activity have been monitored serially in 15 patients with advanced malignant melanoma or renal cell cancer during treatment with concurrent IL-2 and alpha-IFN. Both drugs were given subcutaneously in low to moderate (outpatient) dosages but for a prolonged duration. This treatment resulted in remarkable immunomodulation. In vivo induction of cytotoxicity against K562 and Daudi target cells was consistently seen, and percentages of peripheral blood cells expressing CD 25 (IL-2 receptor) and CD 56 (Leu-19) increased. In vitro proliferation of lymphocytes in response to IL-2 was enhanced during the treatment periods, whereas spontaneous proliferation was inhibited. Moreover, correlations between immune parameters and subsequent clinical responses were present in the early phase of the study. Cytotoxicity levels generated in vivo as well as the percentage of CD 56+ lymphocytes were higher in patients who responded to treatment than in non-responders. In contrast, responders had lower levels of CD 25+ cells. These findings indicate that it might be possible to select patients who are likely to benefit from prolonged immunotherapy. 相似文献
8.
9.
Widespread IgE-mediated hypersensitivity in the Sudan to the 'green nimitti' midge, Cladotanytarsus lewisi (Diptera: Chironomidae) II. Identification of a major allergen. 下载免费PDF全文
A major allergen has been identified in an aqueous extract of the 'green nimitti' midge, Cladotanytarsus lewisi (Diptera: Chironomidae). Following chromatography on Sephadex G-100 allergenic activity, as assessed by skin ('prick') testing, eluted as two closely related peaks (pools I and II) at about 50% bed volume. When these pools were applied separately to columns of CM-cellulose, activity in each eluted with 0 . 05 M NaCl. Isoelectric focusing of the unfractionated allergen gave a single peak of activity at pI 4 . 3. By SDS--PAGE, biological activity in the whole 'green nimitti' extract and the material eluting from both pools I and II of the Sephadex G-100 column migrated to the same positions and were associated with a molecular size of 15,000--20,000 daltons. Skin test reactivity of the unfractionated material and the Sephadex G-100 pool I and II eluates were all destroyed following incubation with trypsin, chymotrypsin, thermolysin and neuraminidase. These experiments indicate that a major allergen derived from the 'green nimitti' midge, a cause of widespread and severe immediate-type allergy in the Sudan, is an acidic glycoprotein of 15,000--20,000 molecular weight. 相似文献
10.
Bilateral simultaneous tubal sextuplets: pregnancy after in-vitro fertilization--embryo transfer following salpingectomy 总被引:2,自引:1,他引:2
The presence of a damaged tube has been suggested in recent studies to have
a negative effect on in-vitro fertilization (IVF) outcome. Performing
bilateral salpingectomy prior to IVF to maximize pregnancy rates may also
result in unnecessary surgery. This case is also an example of the
occurrence of interstitial pregnancy after salpingectomy. This unusual type
of ectopic pregnancy must be kept in mind when evaluating a patient
suspected of a possible early abnormal gestation after assisted
reproductive technolologies.
相似文献