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471.
Psychrophilic microorganisms and their cold-active enzymes 总被引:2,自引:0,他引:2
JE Brenchley 《Journal of industrial microbiology & biotechnology》1996,17(5-6):432-437
472.
Chemical and functional analysis of components of adenylyl cyclase from human platelets treated with phorbolesters 总被引:2,自引:0,他引:2
Human platelets, prelabeled with [32P]phosphate were treated with tetradecanoylphorbol acetate (TPA) for 5 min at 37 degrees C. Phosphorylation of the components of adenylyl cyclase was determined in membranes using specific antibodies against G-proteins and the catalytic moiety. Less than 0.01 mol of [32P]phosphate/mol could be detected in immunoprecipitates using antibodies against sequences within the alpha-subunit of the GTP binding protein Gi. TPA, however, caused the incorporation of 0.67-1.1 mol of [32P]phosphate per mol of catalyst while 0.13-0.2 mol were found in the absence of TPA. Lack of modification of the alpha-subunit of Gi was also indicated by the results of reconstitution experiments with purified Gi alpha from bovine brain: adenylyl cyclase in membranes from untreated platelets was significantly more inhibited by added G1 alpha, than that from TPA treated cells. While beta, gamma-subunits were like-wise inhibitory no difference dependent on platelet-pretreatment could be observed. 相似文献
473.
Peter Wilhelm Ingrid Pilz Karin Goral Walter Palm 《International journal of biological macromolecules》1980,2(1):13-16
This paper presents some data on a human Waldenström immunoglobulin M.IgMGAL based on small-angle X-ray scattering data. the IgMGAL had molecular weight 970 000, volume 1760 nm3, radius of gyration 12 nm and maximum diameter 37 nm. The conclusions from various model calculations are discussed. A flat, star-shaped model is compatible both with X-ray scattering data and electron micrographs. 相似文献
474.
The Sulfolobus isolate B12 and its endogenous virus-like element SSV1 have provided a fruitful system for detailed analysis of certain aspects of archaebacterial molecular biology, especially those concerning gene expression. In the course of clarifying this isolate's taxonomic position, we determined DNA base composition, ability to grow autotrophically, nucleotide sequence of 16S ribosomal RNA, and level of total genomic homology to other Sulfolobus strains. Although the results generally demonstrate a similarity to S. solfataricus, DNA-DNA hybridisation and 16S rRNA sequence data indicate that isolate B12 in fact represents a distinct species.Abbreviations DSM
Deutsche Sammlung von Mikroorganismen, Mascheroder Weg 1 B, D-3300 Braunschweig, FRG
- SDS-PAGE
sodium dodecyl sulphate-polyacrylamide gel electrophoresis 相似文献
475.
476.
Arne Andersson Per-Ola Carlsson Carina Carlsson Richard Olsson Astrid Nordin Magnus Johansson Fredrik Palm Björn Tyrberg Örjan Källskog Linda Tillmar Nils Welsh Göran Mattsson Leif Jansson 《Cell biochemistry and biophysics》2004,40(3):55
Engraftment (i.e., the adaptation of transplanted pancreatic islets to their new surroundings with regard to revascularization, reinnervation, and reorganization of other stromal compartments) is of crucial importance for the survival and function of the endocrine cells. Previous studies suggest that transplantation induces both vascular and stromal dysfunctions in the implanted islets when compared with endogenous islets. Thus the vascular density and the blood perfusion of islet grafts is decreased and accompanied with a capillary hypertension. This leads to hypoxic conditions, with an associated shift toward anaerobic metabolism in grafted islets. An improved engraftment will prevent or compensate for the vascular/stromal dysfunction seen in transplanted islets and thereby augment survival of the islet implant. By such means the number of islets needed to cure the recipient will be lessened. This will increase the number of patients that can be transplanted with the limited material available. 相似文献
477.
Percutaneous ureteral stent placement for the treatment of a benign ureteral obstruction in a Sumatran tiger (Panthera tigris sumatrae) 下载免费PDF全文
478.
Nilsson Christer Sarneel Judith M. Palm Daniel Gardeström Johanna Pilotto Francesca Polvi Lina E. Lind Lovisa Holmqvist Daniel Lundqvist Hans 《Ecosystems》2017,20(1):144-162
Ecosystems - Restoration of channelized streams by returning coarse sediment from stream edges to the wetted channel has become a common practice in Sweden. Yet, restoration activities do not... 相似文献
479.
Cyclins are indispensable elements of the cell cycle and derangement of their function can lead to cancer formation. Recent studies have also revealed more mechanisms through which cyclins can express their oncogenic potential. This review focuses on the aberrant expression of G1/S cyclins and especially cyclin D and cyclin E; the pathways through which they lead to tumour formation and their involvement in different types of cancer. These elements indicate the mechanisms that could act as targets for cancer therapy. 相似文献
480.
Sequence comparison of glyceraldehyde-3-phosphate dehydrogenases from the three urkingdoms: evolutionary implication 总被引:9,自引:0,他引:9
The primary structure of the glyceraldehyde-3-phosphate dehydrogenase from the archaebacteria shows striking deviation from the known sequences of eubacterial and eukaryotic sequences, despite unequivocal homologies in functionally important regions. Thus, the structural similarity between the eubacterial and eukaryotic enzymes is significantly higher than that between the archaebacterial enzymes and the eubacterial and eukaryotic enzymes. This preferred similarity of eubacterial and eukaryotic glyceraldehyde-3-phosphate dehydrogenase structures does not correspond to the phylogenetic distances among the three urkingdoms as deduced from comparisons of ribosomal ribonucleic acid sequences. Indications will be presented that the closer relationship of the eubacterial and eukaryotic glyceraldehyde-3-phosphate dehydrogenase resulted from a gene transfer from eubacteria to eukaryotes after the segregation of the three urkingdoms. 相似文献