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371.
372.
Carpten JD Robbins CM Villablanca A Forsberg L Presciuttini S Bailey-Wilson J Simonds WF Gillanders EM Kennedy AM Chen JD Agarwal SK Sood R Jones MP Moses TY Haven C Petillo D Leotlela PD Harding B Cameron D Pannett AA Höög A Heath H James-Newton LA Robinson B Zarbo RJ Cavaco BM Wassif W Perrier ND Rosen IB Kristoffersson U Turnpenny PD Farnebo LO Besser GM Jackson CE Morreau H Trent JM Thakker RV Marx SJ Teh BT Larsson C Hobbs MR 《Nature genetics》2002,32(4):676-680
We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors. 相似文献
373.
Passage of bracken fern toxicity into milk 总被引:3,自引:0,他引:3
374.
Eleri Jones J. E. W. Davies R. E. Hughes 《Cellular and molecular life sciences : CMLS》1979,35(3):303-304
Summary The extraction, partial purification and assay of a dehydroascorbatase from guinea-pig liver is described. There was no evidence that changes in dehydroascorbatase activity could account for the modified tissue ascorbic acid concentrations associated with ageing or with the ingestion of fluoride, flavonoids or anthocyanin material.Supported by a Beechams Products grant. 相似文献
375.
R. S. Jones R. Heckmann W. Wuersch 《Cellular and molecular life sciences : CMLS》1979,35(9):1209-1210
Summary The effect of halothane on the action of alcuronium on neuromuscular transmission was studied in the intact dog. Electrical and mechanical evoked responses from stimulation of the ulnar nerve were recorded. The administration of 0.5% halothane prolonged the duration of action of alcuronium by about 50%.We are indebted to Professor A. Mueller for facilities, help and encouragement. R.S. Jones was the holder of a Royal Society European Exchange Fellowship. 相似文献
376.
377.
Disturbance to energy production in the S180 sarcoma (CB) by optical isomers of isoproterenol was assessed from altered adenine nucleotide levels at 1 h. The L-isomer almost halved the ATP level and lowered the energy charge significantly; the D-isomer was inactive. Dependence of tumor injury on cytochrome P-450 activity appears unlikely. 相似文献
378.
The tetradecapeptide bombesin was originally isolated from frog skin. Bombesin-like peptides have since been detected in mammalian gastrointestinal tract, brain and lung. These peptides have potent pharmacological effects on the central nervous system; they cause contraction of intestinal, uterine and urinary tract smooth muscle; and stimulate the release of other peptides including gastrin, cholecystokinin, motilin, pancreatic polypeptide, neurotensin, insulin, enteroglucagon, prolactin and growth hormone. Specific plasma membrane receptors for bombesin have been demonstrated on pancreatic acinar cells, brain membranes and pituitary cells. Studies defining the physiological importance of bombesin have been impeded by the lack of a bombesin receptor antagonist. Here we describe experiments which demonstrate that a peptide originally described as a substance P receptor antagonist, [D-Arg, D-Pro, D-Trp, Leu ]substance P, is also a bombesin receptor antagonist. This peptide competitively inhibits the ability of bombesin to stimulate enzyme secretion from dispersed pancreatic acini, and also inhibits the action of other peptides that interact with the bombesin receptor. 相似文献
379.