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排序方式: 共有708条查询结果,搜索用时 15 毫秒
81.
A study of the bryophyte flora of the gypsum outcrops in six sites of the Nature 2000 Network of the Emilia-Romagna Region was conducted in order to contribute to the conservation of the biodiversity of these sites. Subsequently, the main ecological and chorological aspects of the areas were analyzed, and with this information a series of target species was identified as indicators of the conditions of naturality or of progressive anthropization and deterioration of the areas. 相似文献
82.
Thomas R. Noriega Albert Tsai Margaret M. Elvekrog Alexey Petrov Saskia B. Neher Jin Chen Niels Bradshaw Joseph D. Puglisi Peter Walter 《The Journal of biological chemistry》2014,289(28):19294-19305
The signal recognition particle (SRP) directs ribosome-nascent chain complexes (RNCs) displaying signal sequences to protein translocation channels in the plasma membrane of prokaryotes and endoplasmic reticulum of eukaryotes. It was initially proposed that SRP binds the signal sequence when it emerges from an RNC and that successful binding becomes impaired as translation extends the nascent chain, moving the signal sequence away from SRP on the ribosomal surface. Later studies drew this simple model into question, proposing that SRP binding is unaffected by nascent chain length. Here, we reinvestigate this issue using two novel and independent fluorescence resonance energy transfer assays. We show that the arrival and dissociation rates of SRP binding to RNCs vary according to nascent chain length, resulting in the highest affinity shortly after a functional signal sequence emerges from the ribosome. Moreover, we show that SRP binds RNCs in multiple and interconverting conformations, and that conversely, RNCs exist in two conformations distinguished by SRP interaction kinetics. 相似文献
83.
Prof Antonino Ponzo 《Plant biosystems》2013,147(1):119-125
Riassunto Le foglie giovani di Alstroemeria sono guainanti, con guaina fenduta avvolgente il nono; i nomofilli invece ne mancano perchè essa confusasi colla corteccia primaria. La torsione dei filli è dovuta alla loro crescenza asimmetrica spiralata. La fillotassi, dapprima distica, diviene tristica. 相似文献
84.
Modulation by Docosahexaenoic Acid of the Epinephrine-Stimulated Adenylate Cyclase Activity of the Bovine Retina 总被引:2,自引:2,他引:0
Luisa Tesoriere Antonino Bongiorno Maria A. Livrea Antonino Bono 《Journal of neurochemistry》1988,51(3):704-709
This work shows that unsaturated fatty acids enhance the epinephrine-stimulated adenylate cyclase activity in bovine retina. The modulating effect on the epinephrine-stimulated formation of cyclic AMP seems to be linked to the degree of unsaturation of the fatty acid. Treatment of the intact retina with docosahexaenoic acid in the concentration range 0.5 X 10(-6)-1 X 10(-3) M does not affect the enzyme activity measured in the absence of the hormone but markedly increases the cyclase activity when the tissue is incubated in the presence of 0.1 mM epinephrine. Docosahexaenoic acid enhances the maximal response to epinephrine without affecting the apparent ED50 value for this effector. Docosahexaenoic acid at 0.5 mM also increases the hormone-stimulated adenylate cyclase activity in retinal cell-free homogenate, whereas it has no effect on the epinephrine-sensitive enzyme solubilized from the membrane fraction with 1% Triton X-305. When docosahexaenoic acid-preincubated intact retina and cell-free homogenate are incubated in the presence of defatted albumin, both the observed activating effect of the fatty acid on the epinephrine-stimulated adenylate cyclase activity and the enhancement of the enzyme response to the hormone significantly diminish. 相似文献
85.
Jahangir Amin Antonino Puglisi James Clarke John Milton Minghua Wang Ronald M. Paranal James E. Bradner John Spencer 《Bioorganic & medicinal chemistry letters》2013,23(11):3346-3348
We have synthesized a β-cyclodextrin (βCD)-capped histone deacetylase (HDAC) inhibitor 3 containing an alkyl linker and a zinc-binding hydroxamic acid motif. Biological evaluation (HDAC inhibition studies) of 3 enabled us to establish the effect of replacing an aryl cap (in SAHA (vorinostat,)) 1 by a large saccharidic scaffold “cap”. HDAC inhibition was observed for 3, to a lesser extent than SAHA, and rationalized by molecular docking into the active site of HDAC8. However, compound 3 displayed no cellular activity. 相似文献
86.
Ivana Puglisi Valeria Barone Sarah Sidella Mauro Coppa Chiara Broccanello Mara Gennari 《欧洲藻类学杂志》2018,53(3):433-442
The use of microalgae in a number of sectors, including biodiesel, feed and food production, is proving to be of great interest. An evaluation was made of the possible biostimulant effects on Chlorella vulgaris and Scenedesmus quadricauda of humic-like substances (HLs) extracted from agro-industrial wastes. These included digestate from the waste of an agro-livestock farm (D-HL), oil extraction residues from rape (B-HL, Brassica napus L.) and tomato residues (T-HL). The microalgal growth medium (BG11) was supplemented with HLs to evaluate their effect on biomass yield as well as carbohydrate, chlorophylls a and b, lipid and fatty acid contents. Our results showed that the HLs used in the test are effective biostimulants of C. vulgaris and S. quadricauda. The biostimulant effect seems to depend on the type of extract used for cultivating the microalgae, the concentration and the species treated. Among the extracts applied to the growth medium, D-HL and T-HL seem to have a significant effect on microalgal biomass and lipid production. Although B-HL showed no significant effect on the biomass and lipid content of C. vulgaris and S. quadricauda, its presence in the growth medium increased the saturated:unsaturated fatty acid ratio (SFA/UFA) and stimulated the sugar metabolism of the microalgae by increasing their carbohydrate and chlorophyll content. 相似文献
87.
Involvement of sperm acetylated histones and the nuclear isoform of Glutathione peroxidase 4 in fertilization 下载免费PDF全文
88.
Iovinella Manuela Eren Ayla Pinto Gabriele Pollio Antonino Davis Seth J. Cennamo Paola Ciniglia Claudia 《Extremophiles : life under extreme conditions》2018,22(5):713-723
Extremophiles - Cyanidiophytina are a group of polyextremophilic red algae with a worldwide, but discontinuous colonization. They are restricted to widely dispersed hot springs, geothermal... 相似文献
89.
Giorgia Mandili Agata Notarpietro Amina Khadjavi Marco Allasia Antonino Battaglia Barbara Lucatello 《Biomarkers》2018,23(2):123-130
Context: Von Hippel–Lindau disease (VHLD) is a rare inherited neoplastic syndrome. Among all the VHLD-associated tumors, clear cell renal cell carcinoma (ccRCC) is the major cause of death.
Objective: The aim of this paper is the discovery of new non-invasive biomarker for the monitoring of VHLD patients.
Materials and methods: We compared the urinary proteome of VHLD patients, ccRCC patients and healthy volunteers.
Results: Among all differentially expressed proteins, alpha-1-antitrypsin (A1AT) and APOH (beta-2-glycoprotein-1) are strongly over-abundant only in the urine of VHLD patients with a history of ccRCC.
Discussion and conclusion: A1AT and APOH could be promising non-invasive biomarkers. 相似文献
90.
Fiannaca Antonino La Rosa Massimo La Paglia Laura Urso Alfonso 《BMC bioinformatics》2018,19(15):434-71