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A novel vasodilatory peptide from the salivary glands of the sand fly Lutzomyia longipalpis 总被引:4,自引:0,他引:4
Salivary gland lysates of the sand fly Lutzomyia longipalpis contain a potent vasodilator that aids the fly to feed on the blood of its vertebrate hosts. Chromatographic analysis, antibody reactivity, and data obtained from bioassays of the salivary erythema-inducing factor indicate striking similarity with human calcitonin gene-related peptide. The erythema-inducing factor is, however, at least one order of magnitude more potent than calcitonin gene-related peptide. 相似文献
104.
Pyrimidine nucleotide synthesis: regulatory control during transformation of lymphocytes in vitro 总被引:9,自引:0,他引:9
Z J Lucas 《Science (New York, N.Y.)》1967,156(779):1237-1240
The incorporation of uridine into RNA in lymphocytes undergoing transformation induced by phytohemagglutinin parallels its incorporation into the intratcellular pool of acid-soluble nucleotides and coincides with a 20-fold increase in the specific activity of uridine kinase. This increase is dependent upon synthesis of both RNA and protein and is subject to both repression and end-product inhibition by cytidine. 相似文献
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106.
Lucas MS 《Science (New York, N.Y.)》1929,70(1820):482-483
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108.
Lucas GB 《Science (New York, N.Y.)》1980,210(4466):147-153
An epidemic of blue mold of tobacco unexpectedly attacked crops in the United States and Canada in 1979, causing an estimated loss of almost a quarter billion dollars. The disease, caused by a fungus, apparently started in Cuba where half the crop was destroyed in 1979 and 90 percent in 1980. Control of blue mold is difficult and expensive. Resistant cultivars become susceptible within a few years. A therapeutic fungicide, metalaxyl, gives efficient control, but resistant strains of the fungus may soon appear. Blue mold is an international problem that will require the collaboration of scientists, governments, and Industries for an adequate solution. 相似文献
109.
Almeida MP de Melo F Hor-Meyll M Salles A Walborn SP Ribeiro PH Davidovich L 《Science (New York, N.Y.)》2007,316(5824):579-582
We demonstrate the difference between local, single-particle dynamics and global dynamics of entangled quantum systems coupled to independent environments. Using an all-optical experimental setup, we showed that, even when the environment-induced decay of each system is asymptotic, quantum entanglement may suddenly disappear. This "sudden death" constitutes yet another distinct and counterintuitive trait of entanglement. 相似文献
110.
Mulugu S Bai W Fridy PC Bastidas RJ Otto JC Dollins DE Haystead TA Ribeiro AA York JD 《Science (New York, N.Y.)》2007,316(5821):106-109
Inositol pyrophosphates are a diverse group of high-energy signaling molecules whose cellular roles remain an active area of study. We report a previously uncharacterized class of inositol pyrophosphate synthase and find it is identical to yeast Vip1 and Asp1 proteins, regulators of actin-related protein-2/3 (ARP 2/3) complexes. Vip1 and Asp1 acted as enzymes that encode inositol hexakisphosphate (IP6) and inositol heptakisphosphate (IP7) kinase activities. Alterations in kinase activity led to defects in cell growth, morphology, and interactions with ARP complex members. The functionality of Asp1 and Vip1 may provide cells with increased signaling capacity through metabolism of IP6. 相似文献