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1.
2.
K Joubert 《Journal of biosocial science》1991,23(1):39-47
In 10,108 babies born to gypsy parents, birth weight, birth length and gestational age are compared with a national reference sample, taking into account maternal education, age, and birth interval. The gypsy babies tend consistently to be smaller, and this difference is attributable to the circumstances in which the gypsies live as well as the poorer maternal education. There appears to be a vicious circle--poor hygiene and living conditions adversely affect birth size, which in turn puts the child at a disadvantage in terms of survival, health and development. 相似文献
3.
J. C. Seegers L. B. Nieuwoudt W. S. Joubert 《The Journal of steroid biochemistry and molecular biology》1991,38(6):717-720
The 2-hydroxy and 4-hydroxyestradiols (2-/4-OHE2) caused marked cytotoxic effects, including vacuolation and nuclear changes, in rat epididymal epithelia, after exposure to very low levels (40 ng/rat/week) for 20 weeks. The effects of the 2-/4-OHE2 metabolites were more pronounced than that of estradiol-17β(E2). 相似文献
4.
C F van der Merwe J Booyens H F Joubert C A van der Merwe 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(3):199-202
The cytostatic effects of essential fatty acid metabolic intermediates and of some prostaglandins and leukotrienes in vitro have been extensively documented. The essential fatty acids (EFAs) exhibit no side-effects when taken as a dietary supplement, even in large doses. Primary Liver Cancer (PLC) is a fatal disease in our area as it is always multifocal in nature. In vitro studies have shown a cytostatic effect of gamma-linolenic acid (GLA) on primary liver cancer cells. In a double-blind placebo controlled trial, using Evening Primrose Oil (as a source of GLA) as a dietary supplement in PLC patients, no statistically significant effect was observed on survival time or liver size. There was however a statistical significant beneficial effect on Gamma Glutamyl transferase values as a measure of liver function. No side-effects were observed. The large size of tumour and the low doses of GLA used in this trial probably explain the lack of significant effect on survival times. 相似文献
5.
Dihydropyridine calcium antagonists depress the amplitude of the plasma melatonin cycle in baboons 总被引:1,自引:0,他引:1
A C Meyer J J Nieuwenhuis V J Kociszewska W S Joubert B J Meyer 《Life sciences》1986,39(17):1563-1569
An investigation into the effects of verapamil and some dihydropyridine derivatives on plasma melatonin levels was undertaken in baboons. In a number of separate experiments, groups of young male chacma baboons (mean body weight 13 kg) received intraperitoneal injections of the drugs, under ketamine anaesthesia, roughly 30 minutes prior to the following time points: 1200, 1800, 0000, 0200, 0600 and 1200 h. Lights went off at 1800 h and came on at 0600 h. The drugs used, and their respective dosages (expressed per kg body mass), were verapamil up to 4 mg/kg, nifedipine at 0.2 mg/kg, nitrendipine at 0.5 mg/kg and nisoldipine at 0.1 mg/kg. Blood samples, taken at the said time points, were assayed for melatonin. The nighttime peak of the plasma melatonin cycle was significantly depressed by all three dihydropyridine calcium antagonists (up to 40%), while verapamil, even at the relatively high total dose of 24 mg/kg per day, had no significant effect on the circulating plasma melatonin levels. 相似文献
6.
Biotechnology Letters - 相似文献
7.
8.
L A Engel H Menkes L D Wood G Utz J Joubert P T Macklem 《Journal of applied physiology》1973,35(1):9-17
9.
Borrelia burgdorferi is a spirochete pathogen transmitted among warm-
blooded hosts by ixodid ticks. Frequency-dependent selection for variant
outer-surface proteins might be expected to arise in this species, since
rare variants are more likely to avoid immune surveillance in previously
infected hosts. We sequenced the OspA and OspB genes of nine North American
strains and compared them with nine strains previously described. For each
gene, the mean number of synonymous substitutions per synonymous site and
the mean number of nonsynonymous substitutions per nonsynonymous site show
only a twofold excess of silent mutations. Synonymous rates vary widely
along the OspB protein. Some regions show a significant excess of silent
substitutions, while divergence in other regions is constrained by biased
base composition or selection. The presence, in antigenically important
regions of the protein, of significant variation among strains, as well as
evidence for recombination among strains, should be considered in attempts
to develop vaccines against this disease.
相似文献
10.
M P ROBINSON G BUTCHER R H CURTIS K G DA VIES K EVANS 《The Annals of applied biology》1993,123(2):337-347
Two monoclonal antibodies, which differentially recognise the two species of potato cyst nematodes (PCN), Globodera pallida and G. rostochiensis, are described. They have been shown to have potential for quantification of these two species, recognising proteins of the same molecular weight (34 kD) in both species. Further investigation showed these proteins to have isoelectric points at pH values of 5.7 in G. pallida and 5.9 in G. rostochiensis, in common with the proteins used by Fleming & Marks (1983) to differentiate the species of PCN. They are likely to be structurally very similar, with the same physiological function (and therefore similar concentrations) in the two species. In cross-reactivity tests with a wide range of soil nematode species, the antibodies reacted strongly only with species of the genus Globodera, and thereby confirmed their potential as the basis of a quantitative immunoassay likely to be useful in management of PCN populations. 相似文献