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101.
M Dau?a J Hourdry 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(12):973-975
Treatment by thyroxine modified the specific activity of intestianl DNA in premetamorphic Alytes tadpoles. The activity decreased up to the 3rd day, and showed afterwards a peak which culminates on the 9th day. These results have been discussed in comparison with previous radioautographic observations. 相似文献
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103.
Monsuur AJ de Bakker PI Alizadeh BZ Zhernakova A Bevova MR Strengman E Franke L van't Slot R van Belzen MJ Lavrijsen IC Diosdado B Daly MJ Mulder CJ Mearin ML Meijer JW Meijer GA van Oort E Wapenaar MC Koeleman BP Wijmenga C 《Nature genetics》2005,37(12):1341-1344
Celiac disease is probably the best-understood immune-related disorder. The disease presents in the small intestine and results from the interplay between multiple genes and gluten, the triggering environmental factor. Although HLA class II genes explain 40% of the heritable risk, non-HLA genes accounting for most of the familial clustering have not yet been identified. Here we report significant and replicable association (P = 2.1 x 10(-6)) to a common variant located in intron 28 of the gene myosin IXB (MYO9B), which encodes an unconventional myosin molecule that has a role in actin remodeling of epithelial enterocytes. Individuals homozygous with respect to the at-risk allele have a 2.3-times higher risk of celiac disease (P = 1.55 x 10(-5)). This result is suggestive of a primary impairment of the intestinal barrier in the etiology of celiac disease, which may explain why immunogenic gluten peptides are able to pass through the epithelial barrier. 相似文献
104.
Tumour biology: senescence in premalignant tumours 总被引:1,自引:0,他引:1
Collado M Gil J Efeyan A Guerra C Schuhmacher AJ Barradas M Benguría A Zaballos A Flores JM Barbacid M Beach D Serrano M 《Nature》2005,436(7051):642
Oncogene-induced senescence is a cellular response that may be crucial for protection against cancer development, but its investigation has so far been restricted to cultured cells that have been manipulated to overexpress an oncogene. Here we analyse tumours initiated by an endogenous oncogene, ras, and show that senescent cells exist in premalignant tumours but not in malignant ones. Senescence is therefore a defining feature of premalignant tumours that could prove valuable in the diagnosis and prognosis of cancer. 相似文献
105.
TRF2 is a telomere-binding protein that has a role in telomere protection. We generated mice that overexpress TRF2 in the skin. These mice had a severe phenotype in the skin in response to light, consisting of premature skin deterioration, hyperpigmentation and increased skin cancer, which resembles the human syndrome xeroderma pigmentosum. Keratinocytes from these mice were hypersensitive to ultraviolet irradiation and DNA crosslinking agents. The skin cells of these mice had marked telomere shortening, loss of the telomeric G-strand overhang and increased chromosomal instability. Telomere loss in these mice was mediated by XPF, a structure-specific nuclease involved in ultraviolet-induced damage repair and mutated in individuals with xeroderma pigmentosum. These findings suggest that TRF2 provides a crucial link between telomere function and ultraviolet-induced damage repair, whose alteration underlies genomic instability, cancer and aging. Finally, we show that a number of human skin tumors have increased expression of TRF2, further highlighting a role for TRF2 in skin cancer. 相似文献
106.
Resumen El epitelio de transición de cordero contiene actividad de sialidasa. Se demuestra que esta enzima se encuentra en lisosomas de este tejido y posee el pH óptimo ácido característico de enzimas lisosomales.
The technical assistance of MissE. Prado and Mr.L. Iwakawa is acknowledged. This investigation was supported by a grant of the Consejo Nacional de Investigaciones Cientificas y Técnicas of Argentina. 相似文献
The technical assistance of MissE. Prado and Mr.L. Iwakawa is acknowledged. This investigation was supported by a grant of the Consejo Nacional de Investigaciones Cientificas y Técnicas of Argentina. 相似文献
107.
María N. F. de Lew H. Cingolani N. Gonzalez E. S. Blesa J. C. Marsiglia 《Cellular and molecular life sciences : CMLS》1967,23(4):314-315
Résumé Etude de l'équilibre acide-basique de la préparation cur-poumon de l'étourneau, réalisée avec la technique habituelle et les moyens de corriger les altérations constatées. La recherche des causes de ces altérations a permis de conclure que l'alcalose respiratoire est due à la ventilation dont on se sert habituellement, tandis que l'acidose métabolique est due à une production de métabolites acides déclanchés surtout par la saignée des animaux donneurs et par la glucolyse qui se produit à partir de l'extraction du sang et jusqu'au moment de son emploi dans la préparation.
This work has been supported by a grant from the Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. 相似文献
This work has been supported by a grant from the Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. 相似文献
108.
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110.
B Calabretta D L Robberson H A Barrera-Salda?a T P Lambrou G F Saunders 《Nature》1982,296(5854):219-225