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21.
Human cytomegalovirus DNA: BamHI, EcoRI and PstI restriction endonuclease cleavage maps 总被引:12,自引:0,他引:12
The cloned HindIII fragments of human cytomegalovirus (HCMV) strain AD169 DNA were mapped with respect to the BamHI, EcoRI and PstI restriction endonuclease cleavage sites. Composite restriction endonuclease cleavage maps for the entire virus genome were constructed using the previously established linkages between the HindIII fragments. 相似文献
22.
P J Lewis P Boylan L A Friedman C N Hensby I Downing 《BMJ (Clinical research ed.)》1980,280(6231):1581-1582
23.
James M. Phang Sylvia J. Downing Grace Chao Yeh 《Biochemical and biophysical research communications》1980,93(2):462-470
The reactions catalyzed by proline oxidase and pyrroline-5-carboxylate reductase form a catalytic cycle linking the hexose-monophosphate pentose (HMP) pathway to mitochondrial ATP generation. The cycling of proline and pyrroline-5-carboxylate couples glucose oxidation to ATP generation by a mechanism independent of the Embden-Meyerhof pathway and the tricarboxylic acid cycle. 相似文献
24.
Summary A new method is described for the histochemical localization of acid phosphatase. Naphthol AS BI, enzymatically released from naphthyl AS BI phosphoric acid, is coupled with diazotized 2,5-dibromoaniline to produce a fine insoluble red azo dye. The histochemical and cytochemical localization of this final reaction product in rat liver is described. In the electron microscope, sites of the azo dye can be detected by X-ray microanalysis of ultrathin cryosections of reactive tissue.This research was supported by Scientific Research Council Grant No. B/RG/67527 相似文献
25.
Human leukocyte typing sera of known specificities were used to test the leukocyte antigens of vervet monkeys. The results suggest that these leukocytes contained an antigen resembling the HL-A7 antigen of human leukocytes. This is similar to a previous observation with leukocytes from baboons. These findings are consistent with the suggestion that the 4a/4b complex is the precursor substance from which the other specificities have evolved. 相似文献
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27.
This study was designed to investigate changes in cardiac performance during hypoglycemia produced by the administration of insulin in the newborn piglet. With heart rate, aortic pressure, and aortic flow held constant, the treated group demonstrated a pronounced positive inotropic response manifested by an increase of dP/dt max to 138% of control values. Central nervous system function and beta adrenergic activity were excluded from the preparation by ligation of the brachiocephalic vessels and administration of practolol. For reasons discussed, it is unlikely that the findings can be ascribed to glucagon contamination. Therefore, the increase in contractility presumably resulted from a direct effect of insulin upon the myocardium. Clinical and laboratory data suggest that the resistance of the neonate to hypoxia is modified by glycogen stores. Insulin is known to increase glycogen synthesis, and this effect might be expected to augment myocardial resistance to hypoxia. Under the conditions of these experiments, however, pretreatment with insulin had no demonstrable influence on the rate of deterioration of cardiac function during hypoxia. The mechanism of cardiac stimulation by insulin is unknown but may involve calcium fluxes. 相似文献
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29.
Thomas Horn Brian D. Warner Joyce A. Running Kristi Downing Jennifer Clyne Mickey S. Urdea 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):875-877
Abstract Branched oligonucleotides have been synthesized using phosphoramidite derivatives with two protected hydroxyl functions. These molecules are employed for a label amplification strategy used in DNA probe diagnostics. 相似文献
30.
Removal of cholesterol-containing particles from the circulation is mediated by the low-density lipoprotein (LDL) receptor. Upon ligand binding, the receptor-ligand complex is endocytosed, and the ligand is released. The important biological role of the LDL receptor (LDLR) has been highlighted by the identification of more than 400 LDLR mutations that are associated with familial hypercholesterolemia. The extracellular region of the LDLR is modular in nature and principally comprises multiple copies of ligand binding, epidermal growth factor-like (EGF), and YWTD-type domains. This report describes characterization of the calcium binding properties of the tandem pair of EGF domains. While only the C-terminal EGF module contains the consensus sequence associated with calcium binding, a noncanonical calcium binding site in the N-terminal domain has been revealed using solution NMR spectroscopy. The calcium dissociation constants for the N- and C-terminal sites have been measured under physiologically relevant pH and ionic strength conditions using a combination of solution NMR, intrinsic protein fluorescence, and chromophoric chelator methods to be approximately 50 microM and approximately 10-20 microM, respectively. Identification of the novel calcium binding motif in LDLR sequences from other species suggests that it may confer specificity within the LDLR gene family. Comparison of the K(d) for the C-terminal site with the calcium concentration in late vesicles indicates that the binding properties of this module may be tuned to titrate upon endocytosis of the LDL receptor-ligand complex, and thus calcium binding may play a role in the ligand dissociation process. 相似文献