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71.
Marina Giorato Anna Bordin Carla Gemignani Franca Turatello Guido Marcer 《Aerobiologia》2003,19(2):129-131
During recent years a gradual decrease inallergenic airborne pollen concentration hasbeen observed in the monitoring station ofPadua (Italy). Because technical checks of thesampler were not able to explain this trend,the results obtained from two twinpollen-samplers (Lanzoni VPPS 2000), placed twometres apart, were compared.An eight-week sampling was carried out duringthe year 2000 from July to September.Subsequent analysis revealed no statisticallysignificant difference between the dataobtained with the two instruments. On the otherhand, both samplers captured high levels offungal spores. We conclude that the observednegative trend in pollen count is real and notrelated to technical biases. 相似文献
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Marina Aboal María Eugenia García-Fernández Mónica Roldán Brian A. Whitton 《欧洲藻类学杂志》2014,49(1):83-96
The ecology of Chroothece was studied in the highly calcareous Río Chícamo, south-east Spain, in order to explain its success there, but rarity elsewhere. The river, which originates mainly from an underground aquifer, has water with high conductivity, sulphate and nitrate but low phosphate concentrations, the latter mainly organic. Chroothece occurs in mats and in lobed colonies reaching 4 cm in the broadest dimension. The colony surface consists of one layer of cells, each of which is attached to a stalk, which dichotomizes when the cell divides; stalks often extend to the colony base. The central region of many mat cells and almost all colony cells has a yellow to orange-brown colour, associated with the numerous lipid droplets densely covering the surface of the pyrenoid and arms of the star-shaped chloroplast. Field material and laboratory isolates indicate that stalk formation occurs under moderate P limitation and both stalks and cell sheath show high phosphatase activities. This also occurred in a culture collection strain maintained for 30 years in a very P-rich medium, but then transferred to a moderately P-limiting medium (c. 0.9 mg l?1). We suggest that colony formation is initiated by aggregation of motile cells following P pulses in the water. Comparisons are made with Rivularia, a competitor in this nitrate-rich river, in spite of being a N2-fixer. One difference is that Chroothece cells lie at the periphery of the colonies and are therefore exposed to maximum sunlight, whereas Rivularia trichomes grow inside colonies with photoprotection by scytonemin. However, the ability to withstand heavy grazing pressure may be an especially important factor favouring Rivularia here. 相似文献
74.
Mary Henry Noêmi GalAn Katherine Teasdale Renata Prado Harpreet Amar Marina S. Rays Lesley Roberts Pedro Siqueira Gilles de Wildt Marcos Virmond Pranab K. Das 《PLoS neglected tropical diseases》2016,10(3)
BackgroundLeprosy is a leading cause of preventable disability worldwide. Delay in diagnosis of patients augments the transmission of infection, and allows progression of disease and more severe disability. Delays in diagnosis greater than ten years have been reported in Brazil. To reduce this delay, it is important to identify factors that hinder patients from presenting to doctors, and those that delay doctors from diagnosing patients once they have presented. This study aimed to explore factors associated with the delayed diagnosis of leprosy in Brazil.
Methodology/ Principal Findings
This is an exploratory study using a self-constructed questionnaire delivered to patients attending three leprosy referral clinics across three states in Brazil. Data were analysed to determine associations between variables and the time taken for participants to present to the health-service, and between variables and the time taken for doctors to diagnose participants once they had presented. Participants who suspected they had leprosy but feared community isolation were 10 times more likely to wait longer before consulting a doctor for their symptoms (OR 10.37, 95% CI 2.18–49.45, p = 0.003). Participants who thought their symptoms were not serious had a threefold greater chance of waiting longer before consulting than those who did (OR 3.114, 95% CI 1.235–7.856, p = 0.016). Forty-two point six per cent of participants reported initially receiving a diagnosis besides leprosy. These had a three times greater chance of receiving a later diagnosis of leprosy compared to those not misdiagnosed or not given a diagnosis (OR 2.867, 95% CI 1.288–6.384, p = 0.010).Conclusions/ Significance
This study implies a need for patient education regarding leprosy symptoms and the reduction of stigma to encourage patients to present. The high rate of misdiagnosis reported suggests a need to increase clinician suspicion of leprosy. Further education regarding disease symptoms in medical school curriculums may be advisable. 相似文献75.
Gloria Alvarez-Sola Iker Uriarte Maria U. Latasa Maddalen Jimenez Marina Barcena-Varela Eva Santamaría Raquel Urtasun Carlos Rodriguez-Ortigosa Jesús Prieto Pedro Berraondo Maite G. Fernandez-Barrena Carmen Berasain Matías A. Avila 《生物化学与生物物理学报:疾病的分子基础》2018,1864(4):1326-1334
The liver has an extraordinary regenerative capacity rapidly triggered upon injury or resection. This response is intrinsically adjusted in its initiation and termination, a property termed the “hepatostat”. Several molecules have been involved in liver regeneration, and among them bile acids may play a central role. Intrahepatic levels of bile acids rapidly increase after resection. Through the activation of farnesoid X receptor (FXR), bile acids regulate their hepatic metabolism and also promote hepatocellular proliferation. FXR is also expressed in enterocytes, where bile acids stimulate the expression of fibroblast growth factor 15/19 (FGF15/19), which is released to the portal blood. Through the activation of FGFR4 on hepatocytes FGF15/19 regulates bile acids synthesis and finely tunes liver regeneration as part of the “hepatostat”. Here we review the experimental evidences supporting the relevance of the FXR-FGF15/19-FGFR4 axis in liver regeneration and discuss potential therapeutic applications of FGF15/19 in the prevention of liver failure. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen. 相似文献
76.
Marina Rovani Drummond Luciene Silva dos Santos Renata Soalheiro Fvaro Raquel Silveira Bello Stucchi Ilka de Ftima Santana Ferreira Boin Paulo Eduardo Neves Ferreira Velho 《PLoS neglected tropical diseases》2022,16(7)
BackgroundThis study aimed to assess the prevalence of Bartonella sp.-DNA detection in blood and skin samples from patients with non-viral end-stage liver disease awaiting liver transplantation.Methodology/Principal findingsBlood samples and healthy skin fragments from 50 patients were tested using microbiological and molecular methods. Fifteen patients had cryptogenic hepatitis (CH) and 35 had alcoholic, drug-induced or autoimmune liver disease. DNA was extracted from whole blood and liquid culture samples, isolates, and skin fragments. Thirteen of the 50 patients (26%) had Bartonella henselae DNA detection in their blood (9/50) and/or skin (5/50) samples. Colonies were isolated in 3/50 (6%) and infection was detected in 7/50 (14%) of the 50 patients. B. henselae-DNA detection was more prevalent in patients with CH than in other patients (p = 0.040). Of 39 patients followed-up for at least two years, a higher mortality rate was observed among patients with CH infected with B. henselae (p = 0.039).Conclusions/SignificanceFurther studies assessing the role of B. henselae infection in the pathogenesis of hepatitis patients must be urgently conducted. 相似文献
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We have previously reported that treatment of CsA with aqueous HCl gives rise to the formation of a number of water-soluble compounds. Two of these were identified from their FAB-MS/MS spectra as open-chain nona- and decapeptides. We describe here the identification of two other main compounds deriving from the same treatment. Identification was rendered possible from the comparison of their FAB-MS/MS spectra with those of methyl and acetyl derivatives. The two compounds are water-soluble, open-chain undecapeptides corresponding to 1,11 seco-CsA and of 4,5 seco-isoCsA, respectively. 相似文献
80.
Aleksandra Topic Marina Milenkovic Snezana Uskokovic-Markovic Dragana Vucicevic 《Biological trace element research》2010,134(3):296-306
Investigations of effective, orally active, and safe antidiabetic metallopharmaceuticals have been carried out during the
last two decades. It has been reported that tungsten compounds mimic the action of insulin in intact cell systems. As insulin
mimetics, the most investigated tungsten compound was sodium tungstate (ST), rarely investigated was tungstophosphoric acid
(WPA), but never alanine complex of tungstophosphoric acid (WPA-A). In this study, the insulin mimetic activity of three different
tungsten compounds, ST, WPA, and WPA-A, was evaluated by means of in vitro measurements of the glucose uptake and inhibition
of free fatty acids release from epinephrine-treated isolated rat white adipocytes. We investigated the influence of concentration
(lower and higher, 0.1 and 1.0 mM, respectively) and solvent: isotonic salt solution—saline (0.9% w/v of NaCl) and dimethyl sulfoxide (DMSO; 2% v/v), on the biological effect of tested compounds. Our experimental data showed that all of the three investigated tungsten
compounds possess insulin mimetic activity in vitro on the isolated adipocytes. Influence of concentration and solvents on
insulin mimetic effect for the certain tungsten compounds were: WPA was shown effect independently of concentration and solvents;
higher concentration and DMSO were significant decreasing insulin mimetic effect of ST; lower concentration and saline led
to decreasing effect of WPA-A. Generally, there were no differences in insulin mimetic effect of three tungsten compounds
in lower concentration and dissolved in DMSO. When saline was used as solvent, it was needed higher concentration of investigated
compounds to accomplish the same effect. In conclusion, our results suggest that low concentration (0.1 mM) of ST, WPA, and
WPA-A dissolved in 2% DMSO could be the good candidates for in vivo investigation of their antidiabetic properties. 相似文献