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181.
182.
Gabriele Midolo Tomáš Herben Irena Axmanová Corrado Marcenò Ricarda Pätsch Helge Bruelheide Dirk Nikolaus Karger Svetlana Aćić Ariel Bergamini Erwin Bergmeier Idoia Biurrun Gianmaria Bonari Andraž Čarni Alessandro Chiarucci Michele De Sanctis Olga Demina Jürgen Dengler Tetiana Dziuba Giuliano Fanelli Emmanuel Garbolino Gianpietro Giusso del Galdo Friedemann Goral Behlül Güler Guillermo Hinojos-Mendoza Florian Jansen Borja Jiménez-Alfaro Attila Lengyel Jonathan Lenoir Aaron Pérez-Haase Remigiusz Pielech Vadim Prokhorov Valerijus Rašomavičius Eszter Ruprecht Solvita Rūsiņa Urban Šilc Željko Škvorc Zvjezdana Stančić Irina Tatarenko Milan Chytrý 《Global Ecology and Biogeography》2023,32(1):24-34
183.
Dott. Giuliano Montelucci 《Plant biosystems》2013,147(1-2):230-268
Riassunto L'A., descritte succintamente le fitocenosi fanerofitche dei colli Tiburtini e Cornicolani di cui lo Styrax officinalis L. e parte integrante in sorprendente rigoglio, ammette che questa pianta, estesa in Europa nel terziario, abbia regredito nell'attuale areale est-mediterraneo per effetto delle glaciazioni, dopo le quali tenderebbe a ridiffondersi con difficolta a causa della pesantezza dei semi. Rileva quindi l'ipotesi di vari AA., che l'uomo l'abbia reimportata in Italia (forse i Romani a Villa Adriana) e ammette che cio avrebbe permesso alla pianta di diffondersi in una zona di areale virtuale, o piu yerosimilmente pregresso, d'onde forse tende verso l'Atlantico sotto l'influenza della crisi interglaciale xerotermica che si va determinando; ma non nasconde l'intima convinzione chi si tratti di un relitto di indigenato. Accenna quindi ad alcuni popolamenti, in questo settore, di piante mediterrance orientali e occidentali, dalla cui discordanza trae conferma che sul clima di Tivoli influiscono fattori intermedi fra quelli “portoghesi” e quelli “ellenici” di DE MARTONNE. 相似文献
184.
Giuliano Garofolo Andrea Ciammaruconi Antonio Fasanella Silvia Scasciamacchia Rosanna Adone Valentina Pittiglio Florigio Lista 《BMC veterinary research》2010,6(1):11
Background
In Italy, anthrax is endemic but occurs sporadically. During the summer of 2004, in the Pollino National Park, Basilicata, Southern Italy, an anthrax epidemic consisting of 41 outbreaks occurred; it claimed the lives of 124 animals belonging to different mammal species. This study is a retrospective molecular epidemiological investigation carried out on 53 isolates collected during the epidemic. A 25-loci Multiple Locus VNTR Analysis (MLVA) MLVA was initially performed to define genetic relationships, followed by an investigation of genetic diversity between epidemic strains through Single Nucleotide Repeat (SNR) analysis. 相似文献185.
Giuliano Meyer Guido Bottà Carlo Rossetti Dario Cremaschi 《The Journal of membrane biology》1990,118(2):107-120
Summary In rabbit gallbladder epithelium, a Na+/H+, Cl–/HCO
3
–
double exchange and a Na+–Cl– symport are both present, but experiments on intact tissue cannot resolve whether the two transport systems operate simultaneously. Thus, isolated apical plasma membrane vesicles were prepared. After preloading with Na+, injection into a sodium-free medium caused a stable intravesicular acidification (monitored with the acridine orange fluorescence quenching method) that was reversed by Na+ addition to the external solution. Although to a lesser extent, acidification took place also in experiments with an electric potential difference (PD) equal to 0. If a preset pH difference (pH) was imposed ([H+]in>[H+]out, PD=0), the addition of Na-gluconate to the external solution caused pH dissipation at a rate that followed saturation kinetics. Amiloride (10–4
m) reduced the pH dissipation rate. Taken together, these data indicate the presence of Na+ and H+ conductances in addition to an amiloride-sensitive, electroneutral Na+/H+ exchange.An inwardly directed [Cl–] gradient (PD=0) did not induce intravesicular acidification. Therefore, in this preparation, there was no evidence for the presence of a Cl–/OH– exchange.When both [Na+] and [Cl–] gradients (outwardly directed, PD=0) were present, fluorescence quenching reached a maximum 20–30 sec after vesicle injection and then quickly decreased. The decrease was not observed in the presence of a [Na+] gradient alone or the same [Na+] gradient with Cl– at equal concentrations at both sides. Similarly, the decrease was abolished in the presence of both Na+ and Cl– concentration gradients and hydrochlorothiazide (5×10–4
m). The decrease was not influenced by an inhibitor of Cl–/OH– exchange (10–4
m furosemide) or of Na+–K+–2Cl– symport (10–5
m bumetanide).We conclude that a Na+/H+ exchange and a Na+–Cl– symport are present and act simultaneously. This suggests that in intact tissue the Na+–Cl– symport is also likely to work in parallel with the Na+/H+ exchange and does not represent an induced homeostatic reaction of the epithelium when Na+/H+ exchange is inhibited. 相似文献
186.
Giovanna Riccardi Edda De Rossi Giuliano Della Valle Orio Ciferri 《Plant molecular biology》1985,4(2-3):133-136
An 8 Kilobase-pair (Kbp) HindIII fragment containing the coding sequence forSpirulina platensis glutamine synthetase [EC 6.3.1.1.] has been identified utilizing a probe derived fromAnabaena 7120 and cloned in the vector pAT153. 相似文献
187.
Marcella Attimonelli Cecilia Lanave Elisabetta Sbisa Giuliano Preparata Cecilia Saccone 《Cell biochemistry and biophysics》1985,7(4):239-250
A very powerful method for detecting functional constraints operative in biological macromolecules is presented. This method
entails performing a base permanence analysis of protein coding genes at each codon position simultaneously in different species.
It calculates the degree of permanence of subregions of the gene by dividing it into segments,c codons long, counting how many sites remain unchanged in each segment among all species compared. By comparing the base permanence
among several sequences with the expectations based on a stochastic evolutionary process, gene regions showing different degrees
of conservation can be selected. This means that wherever the permanence deviates significantly from the expected value generated
by the simulation, the corresponding regions are considered “constrained” or “hypervariable”.
The constrained regions are of two types: α and β. The α regions result from constraints at the amino acid level, whereas
the β regions are those probably involved in “control” processing. The method has been applied to mitochondrial genes coding
for subunit 6 of the ATPase and subunit 1 of the cytochrome oxidase in four mammalian species: human, rat, mouse, and cow.
In the two mitochondrial genes a few regions that are highly conserved in all codon positions have been identified. Among
these regions a sequence, common to both genes, that is complementary to a strongly conserved region of 12S rRNA has been
found. This method can also be of great help in studying molecular evolution mechanisms. 相似文献
188.
Gerardo Bosco Giuliano Vezzani Simona Mrakic Sposta Alex Rizzato Abdullah Abou-samra 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1501-1505
Early stages of avascular necrosis of the femoral head (AVNFH) can be conservatively treated with hyperbaric oxygen therapy (HBOT). This study investigated how HBOT modulates inflammatory markers and reactive oxygen species (ROS) in patients with AVNFH. Twenty-three male patients were treated with two cycles of HBOT, 30 sessions each with a 30 days break between cycles. Each session consisted of 90?minutes of 100% inspired oxygen at 2.5 absolute atmospheres of pressure. Plasma levels of tumor necrosis factor alfa (TNF-α), interleukin 6 (IL-6), interleukin 1 beta (IL-1β) and ROS production were measured before treatment (T0), after 15 and 30 HBOT sessions (T1 and T2), after the 30-day break (T3), and after 60 sessions (T4). Results showed a significant reduction in TNF-α and IL-6 plasma levels over time. This decrease in inflammatory markers mirrored observed reductions in bone marrow edema and reductions in patient self-reported pain. 相似文献
189.
Amanda Ferreira Cunha Pietro Kiyoshi Maruyama Giuliano Buzá Jacobucci 《Hydrobiologia》2018,806(1):251-264
The behaviour of returning Salmo salar (Linnaeus, 1758) approaching, and attempting to pass low-head weirs remains relatively unknown. A radio telemetry array was created at a low-head weir to enable the behaviour of S. salar (n = 120) to be observed as they approached and attempted to pass the barrier. The majority of fish successfully passed the barrier on their first or second attempt, some individuals required 11 attempts prior to successful passage occurring. Mean delay at the barrier per fish was 47.8 h (±SD 132.0 h), range 15 min to 31 days. Passage success on a fish’s initial attempt was significantly predicted by the amount of searching a fish undertook, fork length, and fat content. Fish were more likely to have a successful first passage attempt if it was smaller with a low fat content and exerted a greater effort in searching for a passage channel. Small-scale barriers cause delays and increased energy expenditure in migrating fish. Barriers may be creating an anthropogenic selection pressure for traits which enable passage success. The impact of a delay at a barrier and increased energy expenditure on reproduction and gonad development remains unknown but is likely to be negatively impacted by instream anthropogenic structures. 相似文献
190.
Elia Zomot Eliane Hadas Yardeni Attilio Vittorio Vargiu Heng-Keat Tam Giuliano Malloci Venkata Krishnan Ramaswamy Michal Perach Paolo Ruggerone Klaas Martinus Pos Eitan Bibi 《Journal of molecular biology》2018,430(9):1368-1385
Secondary multidrug (Mdr) transporters utilize ion concentration gradients to actively remove antibiotics and other toxic compounds from cells. The model Mdr transporter MdfA from Escherichia coli exchanges dissimilar drugs for protons. The transporter should open at the cytoplasmic side to enable access of drugs into the Mdr recognition pocket. Here we show that the cytoplasmic rim around the Mdr recognition pocket represents a previously overlooked important regulatory determinant in MdfA. We demonstrate that increasing the positive charge of the electrically asymmetric rim dramatically inhibits MdfA activity and sometimes even leads to influx of planar, positively charged compounds, resulting in drug sensitivity. Our results suggest that unlike the mutants with the electrically modified rim, the membrane-embedded wild-type MdfA exhibits a significant probability of an inward-closed conformation, which is further increased by drug binding. Since MdfA binds drugs from its inward-facing environment, these results are intriguing and raise the possibility that the transporter has a sensitive, drug-induced conformational switch, which favors an inward-closed state. 相似文献