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Serum activities of aspartate aminotransferase (AspAT = GOT), alanine aminotransferase (AlAT = GPT), and total lactate dehydrogenase (LDH) have been investigated in newborn calves, pigs, and lambs. In the two latter species the LDH isoenzyme distribution in serum was also studied. Blood samples were taken at frequent intervals from birth to 48–72 hrs. post partum. Calves and pigs were born with very low serum enzyme values, whereas lambs showed a picture more similar to what has been reported in human infants. In all species a marked temporary enzyme increase occurred during the first 24–48 hrs. This elevation was found not to be due to colostrum feeding, since a parallel increase was found in starved animals. Possible regulating mechanisms are discussed. The LDH isoenzyme pattern proved to be more stable than total LDH in the early post-natal period. The percentage isoenzyme distribution, however, showed characteristic differences from that found in adult animals of the same species. 相似文献
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Else Nøst Hegseth 《Polar Biology》1989,9(8):479-486
Summary Photoadaptation in some marine Arctic diatoms has been studied. Thalassiosira antarctica, Nitzschia delicatissima and Chaetoceros furcellatus were grown at-0.5°C and various irradiances and continuous light. Growth and cellular chlorophyll were followed during transitional phase after the algae had been transferred from one irradiance to another. Adaptation time for cellular chlorophyll was linearly related to the gradient in irradiance, and adaptation to transfer from high to low light was faster than from low to high light. Adaptation time was found to be species dependent, and Arctic diatoms growing at low temperature seemed to adapt as fast as temperate species.Contribution No. 243 from Trondhjem Biological Station 相似文献
47.
Summary Plasminogen activator inhibitor type-1 (PAI-1) was identified in extracts of rat adrenal medulla, and its immunohistochemical localization was studied together with that of tissue-type plasminogen activator (t-PA). By staining of adjacent sections and by doublestaining of the same section we demonstrate that the same cells of the adrenal medulla contain both PAI-1 and t-PA immunoreactivity in the cytoplasm. In addition a few ganglion cells of the adrenal medulla were found to contain PAI-1 but not t-PA. Neither of the components were found in the adrenal cortex. Analysis of extracts from isolated adrenal medulla using reverse zymography showed the presence of a plasminogen activator inhibitor with M
r46000. The inhibitory activity disappeared when the extract was passed through a column with sepharose-coupled anti-PAI-1 IgG, while the run-through from a similar column coupled with preimmune IgG still contained the inhibitor. The present findings suggest that PAI-1 could play a role in the regulation of t-PA activity in the rat adrenal gland medullary cells. 相似文献
48.
Hubert Wiener Dan A. Klaerke Peter L. Jørgensen 《The Journal of membrane biology》1990,117(3):275-283
Summary In the mammalian distal colon, the surface epithelium is responsible for electrolyte absorption, while the crypts are the site of secretion. This study examines the properties of electrical potential-driven86Rb+ fluxes through K+ channels in basolateral membrane vesicles of surface and crypt cells of the rabbit distal colon epithelium. We show that Ba2+-sensitive, Ca2+-activated K+ channels are present in both surface and crypt cell derived vesicles with half-maximal activation at 5×10–7
m free Ca2+. This suggests an important role of cytoplasmic Ca2+ in the regulation of the bidirectional ion fluxes in the colon epithelium.The properties of K+ channels in the surface cell membrane fraction differ from those of the channels in the crypt cell derived membranes. The peptide toxin apamin inhibits Ca2+-activated K+ channels exclusively in surface cell vesicles, while charybdotoxin inhibits predominantely in the crypt cell membrane fraction. Titrations with H+ and tetraethylammonium show that both high-and low-sensitive86Rb+ flux components are present in surface cell vesicles, while the high-sensitive component is absent in the crypt cell membrane fraction. The Ba2+-sensitive, Ca2+-activated K+ channels can be solubilized in CHAPS and reconstituted into phospholipid vesicles. This is an essential step for further characterization of channel properties and for identification of the channel proteins in purification procedures. 相似文献
49.
Summary Clinical and cytogenetical findings are described in an infant with a de novo deletion of the long arm of chromosome 2. The boy's karyotype is 46,XY, rec(2)delq,t(2;7) (2pter2q34::7p217pter) (7qter7p21::2q362qter). He showed developmental retardation, low-set ears, micrognathia, short neck, abundant skin of the neck, tetralogy of Fallot, bipartite labialike scrotum, clitorislike penis, cryptorchism, and deformities of the hands and feet. 相似文献
50.
Eriksen Karin Landsverk Thor Gondrosen Bjørn Vormeland Jorunn 《Acta veterinaria Scandinavica》1990,31(4):445-451
Antisera against a number of Campylobacter species were used in immuno-histochemical and -cytochemical studies on cases of porcine intestinal adenomatosis. Avidin-biotin-complex (ABC) and streptavidin immunoperoxidase methods were used on formalin-fixed, paraffin-embedded and frozen sections. Protein A gold method was used on formaldehyde fixed and frozen sections for immuno-cytochemistry. The antisera used were raised in rabbits by subcutaneous or intravenous injection of living or formalin treated organisms. Antisera against different serotypes of the thermotolerant, catalase positive Campylobacters, Campylobacter jejuni and Campylobacter coli gave positive reactions in the immuno-histochemical studies. The staining was found in intestinal epithelial cells both in the ileum and in the colon and was restricted to the apical cytoplasm of adenomatous epithelial cells. The staining had a granular pattern, the positive structures sometimes having the shape of Campylobacter. Epithelial cells in areas with normal differentiation of goblet cells did not stain. In contrast, no staining resulted with antisera against Campylobacter sputorum subsp. mucosalis and Campylobacter hyointestinalis. Immuno-cytochemistry, using antisera against Campylobacter jejuni showed that the positive staining in altered epithelial cells were restricted to intracellular organisms having a structure resembling Campylobacter spp. 相似文献