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31.
ANTHONY RAVEL LAURENT MARIVAUX RODOLPHE TABUCE MUSTAPHA BEN HAJ ALI EL MABROUK ESSID MONIQUE VIANEY‐LIAUD 《Palaeontology》2012,55(5):1035-1041
Abstract: Among the new dental remains from the late Early Eocene of Chambi (Kasserine area, Tunisia) is a large‐sized upper molar of a new bat species, Witwatia sigei nov. sp. (Chiroptera, Vespertilionoidea, Philisidae), described herein. The locality of Chambi has revealed evidence for an early appearance of two modern microchiropteran superfamilies in Africa: Dizzya exsultans, a Philisidae, which is considered to be an archaic Vespertilionoidea, and an indeterminate Rhinolophoidea. In addition to D. exsultans, the new species, W. sigei, is the second representative of the Philisidae in this locality. W. sigei extends back to the late Early Eocene the occurrence of the genus Witwatia, which was previously only reported from the early Late Eocene of the Fayum (BQ‐2, Egypt). By analogy with the largest extant microbats, the large size of Witwatia suggests a tendency to the opportunistic diet of this taxon, thereby contrasting with the strict insectivory characterizing primitive bats found in other continents in the same epoch. 相似文献
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Sepsis, a health-threatening progressive infectious disease, is the major cause of morbidity and mortality worldwide. Cell therapy using mesenchymal stromal cells (MSCs) is an innovative strategy with excessive therapeutic potential in the treatment of sepsis. Staphylococcal enterotoxin B (SEB) preconditioning aims to prolong the interval of survival of transplanted MSCs which induces the production of cytoprotective agents, anti-apoptotic and anti-inflammatory factors. The MSCs were preconditioned with an optimum dose of SEB (470 μmol/L). The expression levels of apoptosis genes and antibacterial activity of MSC and SEB-MSC and their conditioned medium (CM), as well as cell survival, were studied in vitro in an oxidative stress and serum deprivation condition. Following treatment of the septic mice with MSCs and SEB-MSCs, pro/anti-inflammatory cytokines, hematological factors, bacterial clearance and animal survival were assessed. The apoptotic and pro-inflammatory cytokine's genes expression was down-regulated while antibacterial peptides and anti-inflammatory cytokines were up-regulated in SEB-MSC–treated mice. The animal survival rates were improved; bacterial clearance was enhanced in the peritoneal fluids, blood and organs; aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were reduced in blood, compared with saline and MSCs alone. This research concludes that transplantation of SEB-MSCs presents improved therapeutic effects on a live bacterial model of sepsis. 相似文献
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Z I ALI V MAHALAKSHMI M SINGH G ORTIZ-FERRARA J M PEACOCK 《The Annals of applied biology》1994,125(2):367-375
In most tropical regions where wheat is grown under irrigation, high temperatures at sowing adversely affect crop establishment and subsequent seedling survival. The objective of this study was to compare wheat (Triticum aestivum) genotypes for their ability to germinate and grow at high temperatures during the seedling stage. Twenty-five seeds each of 14 spring wheat cultivars were placed on moist filter paper at different temperatures (5°C to 40°C) in a one-way thermogradient plate to determine the cardinal temperatures for germination. Rate of germination at each temperature for each genotype was computed as the inverse of time taken for 50% of the seeds to germinate. Rate of germination for each genotype at different temperatures was modelled with temperature to determine the base (tb), and optimum (topt) temperatures. Response of germination to temperature for each genotype was calculated as the slope of a linear regression of the rate of germination on temperature below topt. Genotypes differed in their optimum temperatures and Mexipak (= Kalyansona) had the lowest. Range in base temperature among the genotypes was between 0°C and 2°C differences but were not statistically significant though they might be biologically significant. Genotypes differed in their response to temperature with Gomam having the lowest rate, implying that it was slow to respond to increasing temperatures. Debeira and Cham 6 showed a similar response. Three lines which had performed well in spring wheat evaluation trials for moderate rainfall areas under heat stress had the highest response rate. It is concluded that combining higher optimum temperatures with faster response rates would result in better-adapted germplasm for regions where high temperatures persist at sowing. 相似文献
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Estimates of varietal differences in photosynthesis by ears of wheat, obtained by shading ears or stems, are compared with estimates obtained from a technique involving removal of spikelets at anthesis. The results obtained by different techniques and in different seasons differed widely. 相似文献
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SAMAR BEN MILOUD OLFA DZIRI SANA FERJANI MUNTASIR MD ALI MOHAMED MYSARA ILHEM BOUTIBA ROB VAN HOUDT CHEDLY CHOUCHANI 《Polish journal of microbiology》2021,70(2):161
Environmental bacteria belonging to various families were isolated from polluted water collected from ten different sites in Tunisia. Sites were chosen near industrial and urban areas known for their high degree of pollution. The aim of this study was to investigate cross-resistance between heavy metals (HM), i.e., silver, mercury and copper (Ag, Hg, and Cu), and antibiotics. In an initial screening, 80 isolates were selected on ampicillin, and 39 isolates, retained for further analysis, could grow on a Tris-buffered mineral medium with gluconate as carbon source. Isolates were identified based on their 16S rRNA gene sequence. Results showed the prevalence of antibiotic resistance genes, especially all isolates harbored the blaTEM gene. Some of them (15.38%) harbored blaSHV. Moreover, several were even ESBLs and MBLs-producers, which can threaten the human health. On the other hand, 92.30%, 56.41%, and 51.28% of the isolates harbored the heavy metals resistance genes silE, cusA, and merA, respectively. These genes confer resistance to silver, copper, and mercury. A cross-resistance between antibiotics and heavy metals was detected in 97.43% of our isolates. 相似文献
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The cheer pheasant Catreus wallichi is a globally threatened species that inhabits the western Himalayas. Though it is well established that the species is threatened and its numbers declining, updated definitive estimates are lacking, so in 2011, we conducted a survey to assess the density, population size, and threats to the species in Jhelum valley, Azad Kashmir, which holds the largest known population of cheer pheasants in Pakistan. We conducted dawn call count surveys at 17 points clustered in three survey zones of the valley, 11 of which had earlier been used for a 2002-2003 survey of the birds. Over the course of our survey, 113 birds were recorded. Mean density of cheer pheasant in the valley was estimated at 11.8±6.47 pairs per km2, with significant differences in terms of both counts and estimated density of cheer were significantly different across the three survey zones, with the highest in the Chinari region and the lowest, that is the area with no recorded sightings of the pheasants, in Gari Doppata. The total breeding population of cheer pheasants is estimated to be some 2 490 pairs, though this does not consider the actual area of occupancy in the study area. On the whole, more cheer pheasants were recorded in this survey than from the same points in 2002-2003, indicating some success in population growth. Unfortunately, increasing human settlement, fires, livestock grazing, hunting, and the collection of non-timber forest products continue to threaten the population of cheer in the Jhelum valley. To mitigate these potential impacts, some degree of site protection should be required for the conservation of cheer pheasants in Pakistan, and more effective monitoring of the species is clearly needed. 相似文献