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1.
The effect of single intraperitoneal 1 g.kg-1 doses of a solution of 20 amino acids (AA) on food intake was investigated in 20 piglets examined repeatedly between 2 and 26 days of age. The animals were reared individually from day 1 after birth in cages and bottle-fed a liquid diet nine times per day at two-hour intervals from 6 to 22 h. Although amino acid administration did not significantly affect plasma concentrations of total free AA throughout the experiment (as measured just before and 2 and 5 h after AA administration in blood withdrawn from the external jugular vein) it did produce a downward trend in food intake of piglets at 9-10 d of age. In older animals, the depressive effect on food intake was significantly greater and lasted longer. It is suggested that the aminostatic component of food intake regulation in piglets does not begin to operate until the weaning period. 相似文献
2.
Nutritional and hormonal regulation of mRNA abundance for arginine biosynthetic enzymes in kidney 总被引:2,自引:0,他引:2
Argininosuccinate synthetase and argininosuccinate lyase catalyze the synthesis of arginine from citrulline in kidney and also serve as components of the urea cycle in liver of ureotelic animals. Dietary and hormonal regulation of mRNAs encoding these enzymes have been well studied in liver but not in kidney. Messenger RNAs for these enzymes are localized within the renal cortex. Starvation and extreme variations in dietary protein content (0% vs 60% casein) produced 2.6- to 3.5-fold increases in mRNA abundance for these two enzymes in rat kidney. Argininosuccinate lyase mRNA was not induced by dibutyryl cAMP, dexamethasone, or a combination of the two agents. In contrast, argininosuccinate synthetase mRNA was induced 2-fold by dibutyryl cAMP but was unresponsive to dexamethasone. Thus, diet and hormones regulate levels of these mRNAs in rat kidney, but the responses are both qualitatively and quantitatively distinct from the responses previously reported for rat liver. 相似文献
3.
Josef Holub 《Folia Geobotanica》1988,23(4):383-415
The bookK. Richter, Plantae europeae, Vol. 1, 1890, is analyzed from the viewpoint of nomenclature of subspecies names. 264 subspecies names interesting from the standpoint of contemporary taxonomy and nomenclature are selected from the total number of 840 subspecies names for a commented list. Seventeen important cases are dealt with separately in greater detail. Eleven new nomenclatural combinations (two for species, nine for subspecies) are proposed in the Appendix. Types for two generic names (Acorellus Palla andJuncellus C. B. Clarke) are proposed. A new term “parabasionym” is applied for names establishing the priority of infraspecific epithets in the rank in question. The need to respect the newly accepted principle of priority of autonymic subspecies names at proposing new nomenclatural combinations is stressed. Examples ofRichter’s subspecies names having priority, subspecies names with necessary changes in their authorship and names having a possible importance as parabasionyms are enumerated in separate lists. 相似文献
4.
Chromosome counts of the following 30 taxa (106 populations) are given:Betonica officinalis (2n=16);Bidens frondosus (2n=48);Calamagrostis arundinacea (2n=28+0–2B);Dianthus carthusianorum subsp.latifolius (2n=30);Festuca gigantea (2n=42, 42+2B);Hypericum perforatum (2n=32);Koeleria macrantha (2n=28);Kohlrauschia prolifera (2n=30);Lilium martagon (2n=24+0–2B);Melica ciliata (2n=18);Poa remota (2n=14);Ranunculus polyanthemos (2n=16);R. sardous subsp.sardous (2n=16);Roegneria canina (2n=28+0–1B);Rudbeckia laciniata (2n=76);Scabiosa canescens (2n=16);Serratula tinctoria (2n=22);Seseli elatum subsp.heterophyllum var.beckii (2n=18);S. hippomarathrum (2n=20);Thlaspicaerulescens caerulescens subsp.tatrense (2n=14);Trifolium alpestre (2n=16);T. avense (2n=14);T. medium (2n=79, 80+0–2B, 82);T. rubens (2n=16);Veronica officinalis subsp. alpestris (2n=36);Vincetoxicum hirundinaria (2n=22);Vulpia bromoides (2n=14);Zerna benekenii (2n=28)Z. monoclada (2n=28+0–8B);Z. ramosa (2n=42). Remarks on taxonomy, nomenclature and chorology for some of these taxa are given. 相似文献
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Effect of dietary supplementation with a fish oil concentrate on the alkenylacyl class of ethanolamine phospholipid in human platelets 总被引:2,自引:0,他引:2
It has been demonstrated that the alkenylacyl class of ethanolamine phospholipid (PE) represents one of the major forms of eicosapentaenoic acid (EPA)-containing phospholipid in the circulating platelets isolated from human subjects consuming a fish oil concentrate. Since the alkenylacyl PE from human platelets is enriched in the eicosanoid precursor arachidonic acid (AA) and the n-6 polyunsaturate adrenic acid (AdA), it was of interest to study changes in alkenylacyl PE fatty acid composition upon fish oil supplementation. Healthy volunteers were given 20 capsules of MaxEPA daily (3.6 g of EPA plus 2.4 g of docosahexaenoic acid, DHA) for 6 weeks followed by a 6-week recovery period. Washed platelet suspensions were prepared and the fatty acid compositions of the phospholipid components were evaluated by thin-layer and gas-liquid chromatography at weeks 0, 3, 6, 9, and 12. Fatty acid composition changes were more pronounced in the alkenylacyl PE than in other platelet phospholipids as a result of fish oil consumption. The alkenylacyl PE exhibited a greater drop (by 20.3 mol%, i.e., from 72.0 to 51.7 mol%) in AA than diacyl PE (by 1.6 mol%) or total (predominantly diacyl) choline phospholipids (PC) (by 4.5 mol%). In alkenylacyl PE, the predominant reservoir of AdA in human platelet phospholipid, a dramatic reduction in the level of AdA also resulted with MaxEPA supplementation (from 7.9 to 3.1 mol%); diacyl PE and total PC decreased by 0.6 and 0.3 mol%, respectively. With respect to the n-3 fatty acids, EPA rose by 12.5 mol% in alkenylacyl PE, compared to only 3.8 and 2.5 mol% in diacyl PE and total PC, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Early ventricular fibrillation occurs in approximately 5% of patients admitted for acute myocardial infarction. Although late ventricular fibrillation (> 48 hours postinfarction) may occur in stable patients, it occurs more commonly when severe left ventricular power failure is present. We have encountered late ventricular fibrillation in three of 42 (7%) patients treated with intraaortic balloon pumping (IABP) for profound cardiogenic shock secondary to myocardial infarction. These patients progressed to our hemodynamic Class A prior to weaning, and were thought to be stable prior to IABP removal. They were the only ones who expired after achieving Class A status. The episodes of late ventricular fibrillation occurred after the patients had been successfully weaned from IABP and were free of arrhythmias. This experience suggests that prolonged antiarrhythmic therapy may be indicated for postinfarction patients who have had ventricular dysrhythmias during IABP support. 相似文献
10.
Dr. I. Trebichavský M. Holub L. Jarošková L. Mandel F. Kovářů 《Cell and tissue research》1981,215(2):437-442
Summary The development of lymphoid populations in the omentum majus during the prenatal and postnatal life of the pig was studied. T lymphocytes, monocytes and mast cells were first found on the 40th day of gestation. B lymphocytes appeared on the 72nd day of gestation when the first macrophage aggregates were formed. Macrophages appeared to be the prerequisite for the formation of dense lymphatic areas (DLA's). At later stages T cells were observed only in the omentum of germfree pigs. DLA's of conventional pig omentum are filled exclusively with B cells. 相似文献