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951.
New functions for coenzyme Q 总被引:2,自引:0,他引:2
F. L. Crane 《Protoplasma》2000,213(3-4):127-133
Summary Coenzyme Q is primarily identified with its role in energy coupling where it is involved in the generation of a proton gradient across membranes to drive ATP formation. Its identification as a significant antioxidant throughout cellular membranes is developing. Its function in other membrane redox systems introduces new functions such as the generation of hydrogen peroxide related to cellular signal systems or the acidification of other organelles. A role in the control of cell growth and apoptosis has also been introduced. 相似文献
952.
The substantial retention of Cu2+ and to a lesser extent Zn2+, in the gut mucosa of neonatal MO mutant mice is largely associated with a low molecular weight protein tentatively identified as metallothionein. [35S]Cysteine incorporation into this protein in mutant mice is elevated, indicating that Cu2+ retention in the gut is associated with an increase in the synthesis of metallothionein. The high Cu2+ levels of mutant gut tissue decline rapidly with age to reach an approximately normal level by 24 days of age; this decline cannot be prevented by dietary supplementation and it is suggested that gut 'closure' and consequent reduced uptake by pinocytosis are important factors in this decline. 相似文献
953.
Rena R. Wing Angela M. Pinto Melissa M. Crane Rajiv Kumar Brad M. Weinberg Amy A. Gorin 《Obesity (Silver Spring, Md.)》2009,17(5):991-995
Given the epidemic of obesity, approaches to weight loss that can be applied on a community, state, or national level are needed. We report results from Shape Up Rhode Island 2007 (SURI), a statewide Internet‐based program involving team‐based competition to increase physical activity and achieve weight loss. A total of 4,717 adults (84% women; mean BMI = 29.6 kg/m2) enrolled in the 16‐week weight loss competition of SURI and 3,311 completed at least 12 weeks. Completers reported losing 3.2 ± 3.4 kg, and 30% achieved a clinically significant weight loss of ≥5%. Although modest, these weight losses shifted the BMI distribution from a mean BMI of 29.4 to a mean of 28.2 kg/m2 and reduced the population that was obese from 39 to 31%. More conservative intent‐to‐treat analyses and analysis of 132 participants with objective weights still showed a significant reduction in BMI of ?0.8 units. These findings suggest that statewide weight loss campaigns can produce modest weight losses in large numbers of participants. These data provide a benchmark that can be used for comparisons with other statewide campaigns. Research on ways to improve such campaigns is needed. 相似文献
954.
955.
956.
1,N6-ethenodeoxyadenosine-, 1,N2-ethenodeoxyguanosine- and 3,N4-ethenodeoxycytidine-3'-monophosphates were labeled by [gamma-32P] ATP using T4 polynucleotide kinase in conditions commonly used for the 32P-postlabeling assay. Kinetic studies showed that the reaction is fast reaching a plateau after 15-30 min. The efficiency of phosphorylation, as studied by substrate-product concentration dependency, was between 50-100% at the lower substrate concentrations. The adducts are labeled efficiently at sub-femtomole levels. All the adducts were sensitive to the 3'-dephosphorylation by P1 nuclease although the guanine derivative appeared to be more resistant than the two other adducts. 相似文献
957.
958.
Summary We have previously identified a mutation in the gene for methylmalonyl CoA mutase in a patient with the mut- phenotype of methylmalonic aciduria. This mutation (G717V) interferes with the binding of the deoxyadenosylcobalamin cofactor to the apoenzyme producing a mutant holoenzyme that is defective, but not completely inactive, in vitro. This report describes the clinical phenotype associated with this mutation in the original patient and two additional patients who are homozygous for this allele. All three patients presented in the first years of life with multiple episodes of life-threatening organic acidosis and hyperammonemia. None had evidence of disease in the perinatal period, and all three have low-normal intelligence. These three children exhibit a distinctive phenotype of disease that is intermediate between the fulminant and benign forms of methylmalonic aciduria. These data suggest that this phenotype is the specific consequence of the G717V mutation, and that the degree of residual enzyme activity associated with the G717V mutation is close to the threshold required in vivo for maintaining metabolic homeostasis. 相似文献
959.
960.
Julian C. Crane 《Economic botany》1947,1(3):334-350
In India and other parts of the Old World kenaf has long been of value in the manufacture of gunny cloth, cordage, fishing nets, floor matting and rug backing, and since 1941 investigations have been conducted toward its cultivation in the New World. 相似文献