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531.
The effect of prolonged food deprivation on the triglyceride level in different types of skeletal muscle was studied in the rat. It has been found that fasting gradually reduces the triglyceride content in each muscle type. It is concluded that i.m. triglycerides play an important role as energy fuel during fasting.  相似文献   
532.
An enhancement effect of mouse erythrocyte rosette forming (MERF) cells on the production of migration inhibitory factor, chemotactic factor for neutrophils and skin reactive factor in T-lymphocyte cultures stimulated with the purified protein derivative of tuberculin was observed. We consider it likely that the MERF cells, possessing the appropriate cell surface constituents to construct an immunogenic moiety, present antigen on their surfaces to elicit lymphokine production.  相似文献   
533.
Summary Angiogenic activity, tested on the chorioallantoid membrane of the chicken embryo, was present in the CSF of patients with meningioma and glioblastoma and in patients with other malignancies with no clinical signs of CNS involvement.  相似文献   
534.
Zusammenfassung Mutter-Sohn-Kreuzung bei der südamerikanischen HummelBombus atratus Franklin ergab diploide Männchen mit normalen Arbeiterinnen im Verhältnis von 3 zu 1. Tur Interpretation des genetischen Mechanismus wurden 2 geschlechtsgebundene Loci angenommen, als bisher angenommen wurde, was für einen älteren Mechanismus bei Apiden spricht.

This study was made possible by a grant of the State of São Paulo Research Foundation (FAPESP).

Acknowledgment. I would like to thank Dr.W. E. Kerr, Dr.R. Zucchi and Dr.S. F. Sakagami for their excellent assistance during the course of this investigation as well during the translation. I also would like to thank Dr.R. H. Crozier for his suggestions and comments and I extend my thankfulness to professorsJ. Chaud Netto andZ. Silveira.  相似文献   
535.
A Kótai  T Gánti  I Mécs 《Experientia》1975,31(10):1165-1167
Polycationic modified derivatives of polyglutamic acid are at least as good enhancers of poly I:C induced viral resistance in various cell cultures as are DEAE-dextran or poly-L-lysine.  相似文献   
536.
Résumé L'absence d'un Tm lors de perfusion en quantité croissante de bilirubine non conjuguée chez le rat Gunn, ainsi que la diminution de la concentration biliaire de la bilirubine totale lors d'infusion simultanée de bilirubine non conjuguée et de Novobiocine, suggèrent la possibilité d'un transfert passif de la bilirubine non conjuguée du sang dans la bile, à travers la cellule hépatique.  相似文献   
537.
538.
Summary Chemotactic responsiveness and random movement of cord-blood granulocytes were studied with a modified Boyden's method. Cord-blood granulocytes were less active chemotactically than granulocytes from healthy children and adults, whereas the random filter movement of the cells from all three sources was about the same. In cord sera, concentrations of cell directed chemotaxis inhibitors were equal to those in sera from other age groups. Compared with the situation in healthy children and adults, the generation of chemotactic factors in cord-blood sera was impaired. This impairment was not related to an increased activity of chemotactic factor inactivators. Measurement of the cyclic nucleotide levels in granulocytes from cord-blood and from children belonging to various age groups revealed that the cord granulocytes have significantly lower concentrations of cAMP and cGMP, which could have been responsible for the decreased chemotactic responsiveness.  相似文献   
539.
Summary Depressor responses evoked by single volleys in the aortic nerve are more facilitated by conditioning volleys exciting C fibers in the same aortic nerve than in the contralateral one. Conditioning volleys in A fibers do not facilitate the testing depressor responses.  相似文献   
540.
Detection of HLA-E and -G DNA alleles for population and disease studies   总被引:4,自引:0,他引:4  
HLA-E and -G genes show a restricted polymorphism encoding for molecules whose variability is limited at the peptide binding site. Fourteen alleles that give rise to only three productive proteins for HLA-G (*0101, *0103 and *0104) and five alleles with three different proteins for HLA-E (*0101, *0102 and *0103) have been described. Expression of these molecules is low and found in many tissues for HLA-E; HLA-G protein is expressed in extravillous trophoblast cells and thymic epithelium. Molecular studies have shown how HLA-G and HLA-E bind to natural killer (NK) cells immunoglobulin and lectin-type inhibitory receptors. HLA-E may act as a sentinel of the cell; if classical class I and HLA-G are being expressed, HLA-E molecules may reach the cell surface and inhibit the lysis by NK cells. Most findings are consistent with the hypothesis that HLA-E and -G proteins may be tolerogenic molecules at either the T-cell receptor (TcR) (inflammation, graft rejection) or NK level, switching off cells which usually attack foreign (including foetus) or self (autoimmune) antigens. A low HLA-E and -G polymorphism is observed in humans, and their allele frequencies are mostly homogeneous in the populations tested so far. Many studies to detect these alleles are now being performed in isolated populations and also in pregnancy-associated pathologies. In the present paper, standard and detailed techniques to detect HLA-E and -G DNA polymorphism are reported and discussed. Received 14 July 1999; received after revision 25 August 1999; accepted 25 August 1999  相似文献   
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