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Induction of a cellular enzyme for energy metabolism by transforming domains of adenovirus E1a. 总被引:15,自引:2,他引:13 下载免费PDF全文
R Kaddurah-Daouk J W Lillie G H Daouk M R Green R Kingston P Schimmel 《Molecular and cellular biology》1990,10(4):1476-1483
Brain creatine kinase is a major enzyme of cellular energy metabolism. It is overexpressed in a wide range of tumor cell lines and is used as a tumor marker. We reported recently that the promoter of the human gene has a strong sequence similarity to the adenovirus E2E promoter. This similarity suggested that the brain creatine kinase gene may be regulated by the viral activator E1a. Experiments reported here showed that both enzyme activity and mRNA levels were induced by the oncogenic products of the E1a region of adenovirus type 5, but unlike the viral E2E promoter, which is induced predominantly by E1a domain 3, brain creatine kinase induction required domains 1 and 2. These domains are important for transformation and for the association of E1a with the retinoblastoma gene product and other cellular proteins. The induction by an oncogene of a cellular gene for energy metabolism may be of significance for the metabolic events that take place after oncogenic activation. 相似文献
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Wilfredo Mellado Neal F. Magri David G.I. Kingston Renee Garcia-Arenas George A. Orr Susan Band Horwitz 《Biochemical and biophysical research communications》1984,124(2):329-336
Synthesis and biological activity of 2′-acetyltaxol and 7-acetyltaxol are reported. Activity is measured by cytotoxicity toward the macrophage-like cell line J774.2, and by promotion of microtubule assembly in the absence of exogenous GTP. Addition of an acetyl moiety at C-2′ results in loss of activity but not cytotoxicity. The properties of 7-acetyltaxol are similar to those of taxol in its effects on cell replication and on microtubule polymerization. Therefore a free hydroxyl group at C-7 is not required for activity and this position is available for structural modifications. 相似文献
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Sequences encoding two trypsin inhibitors occur in strikingly similar genomic environments. 总被引:1,自引:0,他引:1 下载免费PDF全文
The nucleotide sequences of two approx. 4 kilobase pair segments of the bovine genome are presented. One segment contains a coding region for bovine pancreatic trypsin inhibitor (BPTI) and the other segment contains a coding region for a BPTI homologue. The two 4 kilobase pair sequences are strikingly similar over approx. 3.4 kilobase pairs of their sequence, including putative intron sequences, suggesting that they have evolved from a gene duplication event. 相似文献
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OBJECTIVES--To estimate the cost effectiveness of giving prophylactic antibiotics routinely to reduce the incidence of wound infection after caesarean section. DESIGN--Estimation of cost effectiveness was based, firstly, on a retrospective overview of 58 controlled trials and, secondly, on evidence about costs derived from data and observations of practice. SETTING--Trials included in the overview were from obstetric units in several different countries, including the United Kingdom. The costing study was based on data referring to the John Radcliffe Maternity Hospital, Oxford. SUBJECTS--A total of 7777 women were included in the 58 controlled trials comparing the effects of giving routine prophylactic antibiotics at caesarean section with either treatment with a placebo or no treatment. Cost estimates were based on data on 486 women who had caesarean sections between January and September 1987. MAIN OUTCOME MEASURE--Cost effectiveness of prophylaxis with antibiotics. RESULTS--The odds of wound infection are likely to be reduced by between about 50 and 70% by giving antibiotics routinely at caesarean section. Forty one (8.4%) women who had caesarean section were coded by the Oxford obstetric data system as having developed wound infection. The additional average cost of hospital postnatal care for women with wound infection (compared with women who had had caesarean section and no wound infection) was estimated to be 716 pounds; introducing routine prophylaxis with antibiotics would reduce average costs of postnatal care by between 1300 pounds and 3900/100 pounds caesarean sections (at 1988 prices), depending on the cost of the antibiotic used and its effectiveness. CONCLUSIONS--The results suggest that giving antibiotics routinely at caesarean section will not only reduce rates of infection after caesarean section but also reduce costs. 相似文献
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ELENA RAEVSKAYA MARCO VECOLI WIESAW BEDNARCZYK MARCO TONGIORGI 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2004,37(1):97-111
Billingen (Lower Arenig/Lower Ordovician) sediments of the St. Petersburg region, northwest Russia and the Leba area, northern Poland of the East European Craton yield acritarch assemblages, which are largely homogenous though displaying minor compositional differences that probably reflect a gradient from inner to outer shelf environments. Comparison with coeval acritarch microflora from the Yangtze Platform, South China, shows an overall similarity between Baltoscandian and South Chinese phytoplankton. The widespread uniformity in the fossil microphytoplankton may be related to the extensive global 'evae' sea-level transgression, which characterized the Billingen time. This suggests that during the Tremadoc through early Arenig times, acritarch assemblages displayed essentially an undifferentiated cold-water and oceanic character along the whole margin of Perigondwana in the South, as well as on the South Chinese and Baltic platforms, at middle latitudes (Mediterranean oceanic Realm). Despite this overall similarity, however, some typical taxa of the high-latitude Mediterranean Province (Arbusculidium, Coryphidium and Striatotheca) occur in South China, but are absent in Baltica. This discrepancy is explained as caused by differences in climatic and physiographic conditions that prevailed at the two palaeocontinents at this time. The inferred pattern of oceanic circulation during the Lower Ordovician is consistent with the palynological evidence of a prevailing warmer climate in Baltica than in South China, although the two palaeocontinents occupied the same palaeolatitudinal position. 相似文献