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Summary The crab (Oziotelphusa) displays a diurnal rhythm of acetylcholinesterase activity, with maximal activity around midnight, alternating with minimal activity at noon. Bilateral eyestalk ablation eliminates the diurnal rhythm of acetylcholinesterase activity.Acknowledgments. We wish to express our gratitude to CSIR, New Delhi for providing financial support to PSR. Reprint requests should be addressed to Prof. R. Ramamurthi.  相似文献   
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Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by activation of the type I interferon (IFN) pathway. Here we convincingly replicate association of the IFN regulatory factor 5 (IRF5) rs2004640 T allele with SLE in four independent case-control cohorts (P = 4.4 x 10(-16)) and by family-based transmission disequilibrium test analysis (P = 0.0006). The rs2004640 T allele creates a 5' donor splice site in an alternate exon 1 of IRF5, allowing expression of several unique IRF5 isoforms. We also identify an independent cis-acting variant associated with elevated expression of IRF5 and linked to the exon 1B splice site. Haplotypes carrying the variant associated with elevated expression and lacking the exon 1B donor site do not confer risk of SLE. Thus, a common IRF5 haplotype driving elevated expression of multiple unique isoforms of IRF5 is an important genetic risk factor for SLE, establishing a causal role for type I IFN pathway genes in human autoimmunity.  相似文献   
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Summary Glucosyltransferase activity in the renal cortex of genetic diabetic KK mice was significantly increased at 40 days of age when compared to that of Swiss albino and F1 hybrid mice. This increase in enzyme activity in the absence of glucose intolerance can be regarded as an earlier genetic marker for the diagnosis of diabetic microangiopathy.Acknowledgments. This research was supported in part by the General Research Support Grant No. RR-05398 from the General Research Support Branch, Division of Research Resources, National Institutes of Health, National Institutes of Health Training Grant No. 5-T01-AM-05617-06, Hope for Diabetics Foundation, Inc., and Pfizer Research Laboratories. Dr.R. A. Camerini-Davalos was a Career Scientist of the Health Research Council of the City of New York, and Drs.A. S. Reddi andC.A. Velasco were N. I. H. Trainees in Diabetes Mellitus during part of this study.  相似文献   
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Summary Activity levels of AMP deaminase and adenosine deaminase have been studied in hepatopancreas, foot and mantle tissues ofPila globosa with reference to starvation and aestivation. The activity levels of both enzymes were decreased in all the tissues of aestivating snails while in starved animals AMP deaminase activity was increased, in contrast to the decreased adenosine deaminase activity.Acknowledgments. K. Srinivasa Moorthy and B. Kasi Reddy are thankful to the Department of Science and Technology, New Delhi for the financial assistance. Reprint requests should be addressed to C.S.C.  相似文献   
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在一个小型固定床反应器上对流化床煤燃烧温度下N_2O均相和多相生成机理进行了试验研究。研究表明,NH_3氧化形成的N_2O量很少,其主要产物是NO,当增加O_2浓度时,N_2O略有增加,在950℃左右时,N_2O量最大,而在880℃时,NO量最大。焦炭直接燃烧能形成一定量的N_2O,NO能在焦炭表面还原成N_2O,氧化性气氛下,焦炭的还原能力降低。最后,对煤焦生成N_2O的多相反应机理进行了讨论。  相似文献   
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Summary Vicia faba root meristem cells treated for 24 h with 1.25 mM hydroxyurea and then X-irradiated contained a large number of cells with both chromosome and chromatid aberrations. X-irradiation 4 h after release from the hydroxyurea block yielded cells with almost exclusively chromatid aberrations.Acknowledgments. This paper is based on work performed under contract with the U. S. Energy Research and Development Administration at the University of Rochester Biomedical and Environmental Research Project and has been assigned Report No. UR-3490-443. This work was also partially supported by USPHS, grants FD-00694 and GM-22680.  相似文献   
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Summary The fat body of the cockroach, Blaberus cranifera, and the silkmoth, Hyalophora gloveri, has been tested for some enzymes of the urea cycle. While ornithine transcarbamoylase and argininosuccinase activities could not be detected, arginase is present in the fat body of these insects. These results explain the essentiality of arginine in the diet of insects.This work was supported by grants from the National Science Foundation (GB-4524 and GB-8172) and the U. S. Public Health Service (AI 05006).Recipient of a Fulbright Travel Grant from the USEFI (New Delhi)  相似文献   
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