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21.
Antonio Lpez-Uceda David Cantador-Fernndez Pedro Raposeiro Da Silva Jorge de Brito Jos María Fernndez-Rodríguez Jos Ramn Jimnez 《Materials》2022,15(15)
This study is framed within the circular economy model through the valorisation of industrial by-products. This research shows the results of producing self-compacting mortars (SCMs) with electric arc furnace dust (EAFD) and other industrial by-products such as fly ash, conforming (FA) or not conforming (NcFA), from coal-fired power plants, or recovery filler (RF) from hot-mix asphalt plants. Three batches of SCMs, each with one industrial-by product (FA, NcFA, or RF), and three levels of EAFD ratio incorporation (0%, 10%, 20%), were tested. An extra batch with a greater amount of FA was manufactured. When the incorporation ratio of EAFD rose, the mechanical strength decreased, due to the presence of a calcium zinc hydroxide dihydrate phase; nevertheless, this decrease diminished over time. All SCM mixes, except the 40C 40FA 20 EAFD mix, were above 20 MPa at 28 days. All mixes named 70C and 40C reached 40 and 30 MPa, respectively, at 90 days. Mixes with EAFD showed less capillarity and no difference in water absorption by immersion with respect to mixes without EAFD after 91 days. The SCMs designed proved to be stable in terms of leaching of the heavy metals contained in EAFD, where all the hardened SCMs were classified as inert. 相似文献
22.
Moraes Tde M Rodrigues CM Kushima H Bauab TM Villegas W Pellizzon CH Brito AR Hiruma-Lima CA 《Journal of ethnopharmacology》2008,120(2):161-168
Ethnopharmacological relevance
Mangaba (Hancornia speciosa Gomez) is a medicinal plant frequently cited in ethnopharmacological inventories of the central region of Brazil against gastrointestinal disorders such as diarrhoea, ulcer, gastritis and stomachache.Aim of the study
The hydroalcoholic extract (HE) and infusion (BI) of Hancornia speciosa bark were investigated for their ability to prevent and heal rodent gastric ulcer.Materials and methods
The preventive and healing action of both preparations of Hancornia speciosa were evaluated in experimental models in rodents that simulated this disease in human gastric mucosa.Results
BI did not exert gastroprotective effect, in contrast to HE (500 mg/kg, p.o.) that decreased (p < 0.05) the severity of gastric damage induced by HCl/ethanol (52%), indomethacin/bethanechol (51%), stress (52%) or pylorus ligature experiments (54%). HE increased (p < 0.05) the pH and decreased acid output of gastric juice. This extract promoted increase of mucus amount (3.62 mg/wt. tissue vs. 5.81 mg/wt. tissue), healing action (67%) and displayed anti-Helicobacter pylori effect.Conclusions
The antiulcer action of Hancornia speciosa resulted in increase of gastric mucus formation and antioxidant properties of polymeric proanthocyanidins present in the bark composition of this medicinal plant. 相似文献23.
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Fernando Luiz de Melo Bernardi Henrique Barbosa Ribeiro Luis Nombela-Franco Enrico Cerrato Gabriel Maluenda Tamim Nazif Pedro Alves Lemos Matias Sztejfman Pablo Lamelas Dario Echeverri Marcelo Antonio Cartaxo Queiroga Lopes Fbio Sndoli de Brito Jr Alexandre A. Abizaid Jos A. Mangione Helene Eltchaninoff Lars Sndergaard Josep Rodes-Cabau 《Arquivos brasileiros de cardiologia》2022,118(6):1085
Background:Transcatheter aortic valve replacement (TAVR) is a worldwide adopted procedure with rapidly evolving practices. Regional and temporal variations are expected to be found.Objective:To compare TAVR practice in Latin America with that around the world and to assess its changes in Latin America from 2015 to 2020.Methods:A survey was applied to global TAVR centers between March and September 2015, and again to Latin-American centers between July 2019 and January 2020. The survey consisted of questions addressing: i) center’s general information; ii) pre-TAVR evaluation; iii) procedural techniques; iv) post-TAVR management; v) follow-up. Answers from the 2015 survey of Latin-American centers (LATAM15) were compared with those of other centers around the world (WORLD15) and with the 2020 updated Latin-American survey (LATAM20). A 5% level of significance was adopted for statistical analysis.Results:250 centers participated in the 2015 survey (LATAM15=29; WORLD15=221) and 46 in the LATAM20. Combined centers experience accounted for 73 707 procedures, with WORLD15 centers performing, on average, 6- and 3-times more procedures than LATAM15 and LATAM20 centers, respectively. LATAM centers performed less minimalistic TAVR than WORLD15 centers, but there was a significant increase in less invasive procedures after 5 years in Latin-American centers. For postprocedural care, a lower period of telemetry and maintenance of temporary pacing wire, along with less utilization of dual antiplatelet therapy was observed in LATAM20 centers.Conclusion:Despite still having a much lower number of procedures, many aspects of TAVR practice in Latin-American centers have evolved in recent years, followingthe trend observed in developed country centers. 相似文献
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Milena de Paiva Cavalcanti Filipe Dantas-Torres Suênia da Cunha Gonçalves de Albuquerque Rayana Carla Silva de Morais Maria Edileuza Felinto de Brito Domenico Otranto Sinval Pinto Brandão-Filho 《Molecular and cellular probes》2013,27(3-4):122-128
American cutaneous leishmaniasis (ACL) caused by Leishmania (Viannia) braziliensis is a neglected disease of humans in the New World that may also cause irreversible skin and eventually mucocutaneous lesions. This parasite can also infect dogs and represents a diagnostic challenge for veterinarians. Methods currently available for the diagnosis of ACL have a low sensitivity and may be time-consuming, representing a limit for treatment expedition of ACL. Quantitative real time PCR assays (qPCR) for the detection of L. (V.) braziliensis in canine blood samples were developed herein, and the detection limit and specificity of different molecular targets (kDNA and rDNA) evaluated. Of the protocols assessed, two qPCR assays, one targeting the kDNA and other the SSU rDNA of L. (V.) braziliensis, performed better, with detection limits of 100 fg and 10 pg, respectively. These assays were also used to test skin samples from humans with suspected ACL. The results indicate that the qPCR protocols developed represent an advance for the diagnosis of ACL in dogs and humans from this region, and provide a rapid and non-invasive diagnosis of the infection by L. (V.) braziliensis. Considering the quantitative nature of the assays, they will also be useful for monitoring treatment efficacy and preventing relapses in human patients in Brazil, although further studies are needed to critically evaluate the specificity of the qPCRs for their capacity to distinguish different Leishmania species and subspecies (represented by zymodemes) in other countries. Finally, molecular assays established may represent new tools for future basic and applied research focused on species identification, host–parasite associations, and infection dynamics in host and vector populations. 相似文献
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29.
Intra-arterial tissue adhesive for medical splenectomy in humans 总被引:2,自引:0,他引:2
30.
Brito EM Camacho-Lobato L Paoletti V Gideon M Katz PO Castell DO 《The American journal of gastroenterology》2003,98(1):40-45
OBJECTIVE: Nutcracker esophagus (NE) is defined as the presence of peristaltic contractions in which the average distal esophageal amplitude is greater than 180 mm Hg. The underlying mechanism responsible for these abnormalities is not known. The aim of this study was to test the hypothesis that NE might be caused by a defect in the inhibitory pathway controlling esophageal peristalsis. METHODS: Eight patients with NE (seven women, 1 man, mean age 50 yr) and eight age- and sex-matched normal volunteers (seven women, 1 man, mean age 48 yr) underwent a special protocol using three-channel (3, 8, and 16 cm above the lower esophageal sphincter) solid state esophageal manometry to evaluate deglutitive inhibition. Ten pairs of 5 ml of wet swallows were given at each of five different time intervals (30, 20, 15, 10, and 5 s). Pairs of swallows were spaced by 30 s, and different time intervals were spaced by 1 min. Tracings were recorded using a computer program and blindly automatically analyzed for both amplitude and duration of the contraction separately for the first and second swallow of each pair. Presence of deglutitive inhibition or muscle refractoriness was assessed according to interactions between the first and second swallow of the pair. Results were found abnormal when larger than the mean percent variation of the second and first swallow calculated for the 30-s interval, considered as baseline for each participant. Statistics included paired and nonpaired nonparametrical comparisons as appropriate. RESULTS: The median amplitude for the NE was 202 mm Hg (range 186-376) and for the controls was 118 mm Hg (range 64-167) (p = 0.0002). The median duration in the NE group was 5.1 s (range 4-9.3) versus 4.1 (range 3.3-5.0) for the controls (p = 0.02). The percent variation in duration (p = 0.31), amplitude (p = 0.42), and propagation velocity of the peristaltic waves (p = 0.69) did not differ between the control and NE groups. Peristalsis frequency dropped at the 5-s interval for both studied groups (p = 0.84). CONCLUSION: Central and local inhibitory mechanisms induced by closely timed swallows are preserved in the NE and do not explain the mechanism of the high amplitude and long duration contractions. 相似文献