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Multiple basal promoter elements determine the level of human c-fos transcription. 总被引:7,自引:2,他引:5 下载免费PDF全文
L Runkel P E Shaw R E Herrera R A Hipskind A Nordheim 《Molecular and cellular biology》1991,11(3):1270-1280
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Changes with starvation in the rat of the lipoprotein lipase activity and hydrolysis of triacylglycerols from triacylglycerol-rich lipoproteins in adipose tissue preparations. 下载免费PDF全文
Lipoprotein lipase activity was higher in fat-pad pieces than in isolated adipocytes from the same fed rats, whereas hydrolysis of triacylglycerols from triacylglycerol-rich lipoproteins was similar in the two preparations when incubated either in basal conditions or in the presence of heparin. In both preparations there was a similar release of lipoprotein lipase activity into the medium during basal incubation, enhanced by the presence of heparin. In fat-pad pieces, but not in isolated adipocytes, incubation with heparin produced a decrease in the lipoprotein lipase activity measured in the tissue preparation. In fat-pad pieces from 24 h-starved rats, lipoprotein lipase activity was the same as in isolated adipocytes from the same animals and incubation with heparin did not affect the appearance of lipoprotein lipase in the medium or the utilization of triacylglycerols from triacylglycerol-rich lipoproteins. These results support the following conclusions. (1) The effectiveness of lipoprotein lipase in adipose tissue preparations in vitro depends more on its availability to the substrate than on its total activity. (2) Heparin acts on adipose tissue preparations from fed animals both by enhancing the release of pre-existing extracellular enzyme (which is absent in isolated adipocytes) and by enhancing the transfer outside the cells of the intracellular (and mainly undetectable) enzyme that is activated in the secretion process. (3) In adipose tissue from starved animals there is not only a decrease in the active extracellular form of lipoprotein lipase activity but also a reduction in the intracellular (and mainly undetectable) pool of the enzyme. 相似文献
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R. J. Haroun W. F. Prud'homme van Reine D. G. Müller E. Serrao R. Herrera 《Helgoland Marine Research》1993,47(2):125-143
Due to the geographical location and paleobiogeography of the Canary Islands, the seaweed flora contains macroalgae with different
distributional patterns. In this contribution, the biogeographical relations of several new records of deep-water macroalgae
recently collected around the Canarian archipelago are discussed. These areBryopsidella neglecta (Berthold) Rietema,Discosporangium mesarthrocarpum (Meneghini) Hauck,Hincksia onslowensis (Amsler et Kapraun) P. C. Silva,Syringoderma floridana Henry,Peyssonnelia harveyana J. Agardh,Cryptonemia seminervis (C. Agardh) J. Agardh,Botryocladia wynnei Ballantine,Gloiocladia blomquistii (Searles) R. E. Norris,Halichrysis peltata (W. R. Taylor) P. Huvé et H. Huvé,Leptofauchea brasiliensis Joly, andSarcodiotheca divaricata W. R. Taylor. These new records, especially those in the Florideophyceae, support the strong affinity of the Canary Islands
seaweed flora with the warm-temperate Mediterranean-Atlantic region. Some species are recorded for the first time from the
east coast of the Atlantic Ocean, enhancing the biogeographic relations of the Canarian marine flora with that of the western
Atlantic regions. 相似文献
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Triglyceride-rich lipoproteins from adult rat plasma were labelled in vivo with 3H in the esterified fatty acids and 14C in the labelled glyceride glycerol of neutral lipids by injecting i.v. sodium 9-10 (n)-[3H] palmitate and [U-14C] glycerol, after which the prelabelled lipoproteins were purified by ultracentrifugation and dialysis. The lipoproteins were incubated in vitro, in the presence or not of heparin, with pieces of epididymal fat pads or isolated adipocytes from fed rats. The disappearance of both [3H]- and [14C] lipids from the media was greater when incubations were performed with adipocytes than with fat-pad pieces and it increased with heparin in both preparations. More 3H-label than 14C was found in the tissue lipids, a higher percentage being present in adipocytes than in fat-pad pieces, and the amount of label in tissue lipids was always enhanced by heparin. Some 14C-label appeared as esterified fatty acids in both tissue preparations and it also was enhanced by the presence of heparin. These findings are in agreement with the recognized influence of heparin on the release of lipoprotein lipase and show the direct relationship between heparin action and tissue ability to take up products of lipoprotein triglyceride breakdown. They also demonstrate the ability of adipose tissue to metabolize glycerol coming from the hydrolysis of lipoprotein glycerides. 相似文献
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Byron J. Good Henry Herrera Mary-Jo Delvecchio Good James Cooper 《Culture, medicine and psychiatry》1982,6(3):281-303
A Mexican-American woman who complained of persistent head pain and a bothersome voice was seen by a team consisting of a psychiatrist, social scientists, and spiritualist healers in a Cultural Consultation Clinic of a Psychiatric Consultation Liaison Service. This single case is analyzed to provide an understanding of the interpretive dimensions of psychiatric practice. It is argued that a hermeneutic analysis of clinical phenomena focuses attention on three distinct aspects of interpretation: on the interpretation by clinicians and clients of the discourse of the other in terms of their own clinical models; on the influence of deeply embedded personal meanings on this interpretive process; and on the role of the observer in clinical ethnography. It is argued that to sustain a hermeneutic analysis of psychiatric practice, an account of transference and countertransference in terms of interpretation theory will have to be developed. 相似文献
8.
Carlos M. Herrera 《Oecologia》1976,25(2):187-191
Summary An index to assess trophic diversity from presence-absence food data is proposed. The index is computed according to the expression
, where the
's are the frequencies of occurrence of the various prey categories. The upper and lower limits of D are derived. A test of the reliability of D was carried out by comparing D and H (Shannon's information function) values obtained from a set of twenty-three food analyses from vertebrate animals. Results show that, although a significant correlation exists between D and H, only a small fraction of H-variation is explained by D-variation. D contains two kinds of information, one referred to species richness and another relative to the degree of between-samples heterogeneity. The former is shared in common with H and this presumably explains the fairly weak correlation found between both measures. 相似文献
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A. C. S. A. Herrera C. Panis V. J. Victorino F. C. Campos A. N. Colado-Simão A. L. Cecchini R. Cecchini 《Cancer immunology, immunotherapy : CII》2012,61(11):2193-2201
Breast cancer consists in a chronic inflammatory disease with multiple biological and clinical behaviors. Based on high throughput technologies data, this disease is currently classified according to the molecular expression of estrogen (ER), progesterone (PR) and human epidermal growth factor (HER-2) receptors. In this study, we defined the inflammatory profile of the main molecular subtypes of breast cancer patients: luminal (ER and PR positive, HER-2 negative), HER-2 enriched (HER-2 positive) and triple negative (ER, PR and HER-2 negative). Cytokines panel was assessed by measurement of TNF-α, TGF-β, IL-1, IL-10 and IL-12 plasmatic levels. Oxidative profile was assessed by determination of lipid peroxidation, total antioxidant capacity of plasma, malondialdehyde levels, carbonyl content and nitric oxide (NO). Clinical data were correlated with inflammatory findings. Our findings demonstrated that patients bearing the luminal subtype displayed high TNF-α, TGF-β and enhanced oxidative stress levels associated with reduced IL-12. HER-2-enriched group exhibited higher levels of TNF-α, IL-12 and TGF-β associated with enhanced oxidative stress. Triple-negative subtype exhibited the most aggressive profile of disease behavior, with reduction in both TNF-α and TGF-β, with high levels of lipid peroxidation and NO. The clinical importance of our findings lies in the fact that the inflammatory status varies in distinct ways due to molecular subtype of breast cancer, opening potential therapeutic targets to future therapies. 相似文献