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271.
Gianni Bedini Angelino Carta Giovanni Zecca Fabrizio Grassi Gabriele Casazza Luigi Minuto 《Plant Systematics and Evolution》2011,294(3-4):273-280
Rhamnus glaucophylla Sommier is an endemic small tree or shrub belonging to sect. Eurhamnus. It grows on cliffs of the Apuan Alps and of the Lucca Apennine in Tuscany (Italy). ISSRs were used to detect the genetic diversity within and among five populations representative of the species distribution range. Moderate levels of genetic diversity were revealed as percentage of polymorphic band (PPB) both at the population (PPB?=?22.63%, H S?=?0.0801, Sh?=?0.1193) and species level (PPB?=?48.68%, H T?=?0.1155, Sh?=?0.1837). The correlation between genetic and geographic distances was not significant (Mantel test, r?=?0.17; P?<?0.26). The information on the pattern of genetic variation obtained in this work bears important implications for conservation management, and in particular for ex situ conservation programmes involving long-term seed storage in seed banks. 相似文献
272.
William P. Wergin Robert W. Yaklich Lynn K. Carta Eric F. Erbe Charles A. Murphy 《Journal of nematology》2000,32(2):198-204
Juveniles of five species of nematodes, Caenorhabditis elegans, Panagrellus redivivus, Pratylenchus agilis, Pristionchus pacificus, and Distolabrellus veechi, were added to solutions with (treatment) and without (control) a commercial ice-nucleating activity (INA) agent. Ten-microliter droplets of the solutions containing the juveniles were placed on glass microscope slides and transferred to a temperaturecontrolled freeze plate where the temperature was reduced to -6 to -8 °C. At this temperature, the droplets containing the INA agent froze while those without the agent remained liquid. After 2 minutes, the temperature of the plate was raised to 24 °C, and the slides were examined with a light microscope to determine the viability of the juveniles. The results showed that usually most juveniles (43% to 88%, depending on species) in solutions that did not contain the INA agent (controls) were active, indicating that the juveniles were capable of supercooling and were thereby protected from the subzero temperatures. Alternatively, less than 10% of the juveniles that had frozen for 2 minutes in solutions containing the INA agent remained viable, indicating that inoculative freezing of the solution was lethal to the supercooled juveniles. Our results suggest that, in geographical areas where winter temperatures may not be sufficiently low or sustained to freeze soil, the addition of an INA agent may help induce ice nucleation and thereby reduce the populations of nematode species that are unable to survive when the soil solution is frozen. 相似文献
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Laura Grauso Gaspare Cesarano Maurizio Zotti Marta Ranesi Wen Sun Giuliano Bonanomi Virginia Lanzotti 《Phytochemistry Reviews》2020,19(3):659-689
Dittrichia viscosa is a perennial small shrub belonging to the Compositae family (Asteraceae) widespread in the Mediterranean basin. This plant has been ex 相似文献
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Anna R. Carta Anil Kachroo Nicoletta Schintu Kui Xu Michael A. Schwarzschild Jadwiga Wardas Micaela Morelli 《Journal of neurochemistry》2009,111(6):1478-1489
Adenosine A2A receptors antagonists produce neuroprotective effects in animal models of Parkinson’s disease (PD). As neuroinflammation is involved in PD pathogenesis, both neuronal and glial A2A receptors might participate to neuroprotection. We employed complementary pharmacologic and genetic approaches to A2A receptor inactivation, in a multiple MPTP mouse model of PD, to investigate the cellular basis of neuroprotection by A2A antagonism. MPTP·HCl (20 mg/kg daily for 4 days) was administered in mice treated with the A2A antagonist SCH58261, or in conditional knockout mice lacking A2A receptors on forebrain neurons (fbnA2AKO mice). MPTP‐induced partial loss of dopamine neurons in substantia nigra pars compacta (SNc) and striatum (Str), associated with increased astroglial and microglial immunoreactivity in these areas. Astroglia was similarly activated 1, 3, and 7 days after MPTP administration, whereas maximal microglial reactivity was detected on day 1, returning to baseline 7 days after MPTP administration. SCH58261 attenuated dopamine cell loss and gliosis in SNc and Str. Selective depletion of A2A receptors in fbnA2AKO mice completely prevented MPTP‐induced dopamine neuron degeneration and gliosis in SNc, and partially counteracted gliosis in Str. Results provide evidence of a primary role played by neuronal A2A receptors in neuroprotective effects of A2A antagonists in a multiple MPTP injections model of PD. With the symptomatic antiparkinsonian potential of several A2A receptor antagonists being pursued in clinical trials, this study adds to the rationale for broader clinical benefit and use of these drugs early in the treatment of PD. 相似文献
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Kinetic characterization of the inhibition effect of nickel on glucose-6-phosphate dehydrogenase (EC 1.1.1.49) (G-6-PD) and glutathione reductase (GR; EC 1.6.4.2) from Saccharomyces cerevisiae was made. The effect of nickel on G-6-PD activity is consistent with a mixed-type inhibition pattern, with a competitive character, since the inequality ki,int greater than ki,slope shows an inverse relation between varied substrate concentrations and fractional inhibition. An inhibition effect of nickel on GR activity, when NADPH is the varied substrate, is also consistent with a mixed-type inhibition pattern. However, pure competitive inhibition is found on GR reaction when oxidized glutathione is the varied substrate. This investigation shows the highest sensibility of GR before the inhibitory effect of nickel, in agreement with the experimental values of inhibition constants found in this study, where constants related to the GR system are lower than the ones of the G-6-PD system. 相似文献
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