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624.
G R Davis S J Campbell D I McGregor 《Archives internationales de physiologie et de biochimie》1983,91(5):443-450
Larvae of the yellow mealworm, Tenebrio molitor L., Gembloux strain, race F, were reared on diets in which the protein component was supplied by defatted ground seed, defatted ground dehulled fraction, or defatted ground hulls of Brassica napus L. cv. Tower or Brassica campestris L. cv. Candle, obtained from autoclaved seed. They were also fed casein diets to which defatted ground hulls of Tower or Candle seed were added. Gain in weight was equally good for all diets containing Candle seed fractions and for diets containing Tower ground seed. However, it was lower for diets containing the ground dehulled fraction or the ground hulls of Tower. Addition of Candle hulls or of a mixture of equal proportions (w/w) of Candle and Tower hulls to diets containing dehulled Tower did not improve the gain in weight of larvae, compared with that of larvae fed diets containing the dehulled fraction, alone. Similar additions of Tower hulls or of the mixture to diets containing the dehulled fraction of Candle had no adverse effect on larval gain in weight, compared to that registered by larvae fed the dehulled fraction of Candle. Significant improvement in weight gain in comparison with that recorded for larvae fed the unsupplemented casein diet could not be demonstrated when ground hulls of Tower or Candle were added to this diet. Considered collectively, weight gains of larvae of T. molitor were consistently greater when Candle products were fed than when Tower products provided the protein fraction of the diet. 相似文献
625.
626.
In a prospective study designed to assess the influence of bromocriptine on pituitary tumour size 12 patients with pituitary tumours, eight of whom had suprasellar extensions, were treated for three months with 20 mg of bromocriptine daily after a gradual increase to this dose. The group comprised eight women and four men, five with prolactin-secreting adenomas, four with acromegaly, two with functionless adenomas, and one with Nelson''s syndrome. All five patients with prolactin-secreting adenomas showed a reduction in pituitary tumour size as assessed by computerised tomography and metrizamide cisternography accompanied by a fall in prolactin concentrations and clinical and biochemical improvement in their hypopituitarism. One patient in this group had a visual-field defect before treatment, and this resolved. There was no radiological evidence of reduction in tumour size in the remaining seven patients, though this might refect the fairly short duration of treatment, particularly in view of the ancillary evidence of clinical, biochemical, and visual-field improvement in some of the patients. These results emphasise the potential value of bromocriptine in treating patients with large prolactinomas or recurrences of such tumours after previous chiasmal decompression and conventional external megavoltage irradiation on the pituitary. 相似文献
627.
Summary The development of common scab on potato crops growing in slightly acid to neutral soils has been shown to be greatly reduced by application of manganese sulphate to the soil at planting time. A general improvement in health and appearance of tubers was noted and increased yields of marketable tubers were obtained. The possibility that environmental factors known to influence the development of scab are only important in so far as they affect the solubility of soil manganese is discussed. 相似文献
628.
T cell-mediated cytotoxicity induced by Listeria monocytogenes. III. Phenotypic characteristics of mediator T cells 总被引:1,自引:0,他引:1
M C Woan D D McGregor I Goldschneider 《Journal of immunology (Baltimore, Md. : 1950)》1981,127(6):2330-2334
Cytotoxic thymus-derived lymphocytes (CTL) generated in vitro by restimulating rat cells with Listeria antigen- (LMA) pulsed syngeneic accessory cells were characterized in respect to their surface membrane markers. LM-dependent CTL were devoid of detectable surface immunoglobulin (Ig) and receptors for the Fc region of rabbit IgG. Experiments with monoclonal antibodies to rat T cell markers revealed that these cytotoxic cells have the phenotypic profile W3/13+, W3/25-, MRC OX 8+. LM-dependent CTL also bind the monoclonal antibody, MRC OX 3, which recognizes an Ia-antigen-like determinant on rat cells. Although LM-dependent CTL lack the W3/25 marker, their generation depends on the cooperative interplay of W3/25+ and W3/25- T cells. 相似文献
629.
J Donaldson D McGregor F LaBella 《Canadian journal of physiology and pharmacology》1982,60(11):1398-1405
In man, manganese neurointoxication is characterised in the early phase by behavior reminiscent of that observed in schizophrenia. During chronic manganese intoxication the neuropsychiatric symptoms manifested earlier disappear and are followed by a permanent neurological phase typified by extrapyramidal symptoms similar to those of Parkinson's disease. Study of manganese intoxication in animals may provide important clues towards elucidation of the biochemical defect underlying neuropsychiatric as well as extrapyramidal disease. Investigations in our laboratory suggest that neurotoxicity of manganese is an exaggeration of function in normal neuronal homeostasis. Manganese neurointoxication in neonatal rats resulted in significant depression of lipid peroxidation in several rat brain regions examined. In the striatum, lipid peroxidative activity was abolished, an effect which may be related to alteration in neurotransmitters often observed in the striatum of manganese treated rats. The chronic, extrapyramidal stage of manganism, may ensue when excess Mn2+ is oxidised to higher valency forms where it can potentiate the autoxidation of catecholamines, like dopamine, resulting in concomitant formation of free radicals and cytotoxic quinones. This latter effect may arise preferentially in the substantia nigra, where neuromelanin is formed nonenzymatically by autoxidation of dopamine. 相似文献
630.
John L. McGregor 《Bulletin of mathematical biology》1970,32(2):249-262
Deakin (1967b) suggested that flow of blood might obey a law of minimal energy dissipation. The present paper presents a simpler
derivation of Deakin’s equations pointing out several previously unrecognized features. It is shown that these equations are
unlikely to be applicable. In particular, the solution obtained by Deakin and Jones (1968) does not yield a true minimum for
energy dissipation. The solution for which energy dissipation is actually minimized is shown to possess features which render
it unlikely to apply to a real flow. 相似文献