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991.
Tavares DC Varanda EA Andrade FD Vilegas W Takahashi CS 《Journal of ethnopharmacology》1999,68(1-3):115-120
Paepalantine is an isocoumarin isolated from Paepalanthus vellozioides which showed antimicrobial activity in in vitro experiments. In the present study, paepalantine was tested for possible clastogenic and cytotoxic action. Cultures from different individuals were treated with paepalantine at concentrations of 20, 40 and 80 microg/ml. The effect of isocoumarin was also tested in an in vivo assay using Wistar rat bone marrow cells. Paepalantine was administered intraperitoneally at concentrations of 6.25, 12.5 and 25 mg/kg body weight. Under these conditions paepalantine did not have a clastogenic effect, but was significantly cytotoxic in the in vitro and in vivo mammalian cell systems tested in the present work. 相似文献
992.
Souza DG Cara DC Cassali GD Coutinho SF Silveira MR Andrade SP Poole SP Teixeira MM 《British journal of pharmacology》2000,131(8):1800-1808
The effects of the long lasting and potent PAF receptor antagonist UK74505 were assessed on the local and remote injuries following ischaemia and reperfusion (I/R) of the superior mesenteric artery (SMA) in rats. In a severe model of ischaemia (120 min) and reperfusion (120) injury, in addition to the local and remote increases in vascular permeability and neutrophil accumulation, there was significant tissue haemorrhage, blood neutropenia, systemic hypotension and elevated local and systemic TNF-alpha levels. Post-ischaemic treatment with the selectin blocker fucoidin (10 mg kg(-1)) prevented neutrophil accumulation in tissue and, in consequence, all the local and systemic injuries following severe I/R. Treatment with an optimal dose of UK74505 (1 mg kg(-1)) also reversed local and remote neutrophil accumulation, increases in vascular permeability and intestinal haemorrhage. UK74505 partially inhibited blood neutropenia and reperfusion-induced hypotension. Interestingly, both fucoidin and UK74505 prevented the local, but not systemic, increases of TNF-alpha levels following severe I/R injury, demonstrating an important role of migrating cells for the local production of TNF-alpha. However, the results do not support a role for PAF as an intermediate molecule in the production of systemic TNF-alpha. The beneficial effects of UK74505 and other PAF receptor antagonists in models of I/R injury in animals and the safety of UK74505 use in man warrant further investigations of the use of this drug as preventive measure for I/R injury in humans. 相似文献
993.
As stroke mortality rates according to race were not known in Brazil, data on
mortality for the year 2010 was collected from the Mortality Information System
of the Brazilian Ministry of Health. Cerebrovascular mortality rates adjusted
for age (per 100,000) were calculated with a confidence interval of 95% (95%CI)
by sex and race/skin color. The differences between races were significant for
men with rates of 44.4 (43.5;45.3), 48.2 (47.1;49.3) and 63.3 (60.6;66.6) for
white, brown and black, respectively; and for women, with rates of 29.0
(28.3;29.7), 33.7 (32.8;34.6) and 51.0 (48.6;53.4) for white, brown and black,
respectively. The burden of stroke mortality is higher among blacks compared to
brown and white. 相似文献
994.
Harry Acquatella Federico M. Asch Marcia M. Barbosa Marcio Barros Caryn Bern Joao L. Cavalcante Luis Eduardo Echeverria Correa Joao Lima Rachel Marcus Jose Antonio Marin-Neto Ricardo Migliore Jose Milei Carlos A. Morillo Maria Carmo Pereira Nunes Marcelo Luiz Campos Vieira Rodolfo Viotti 《Journal of the American Society of Echocardiography》2018,31(1):3-25
995.
996.
The purpose of this article is to review studies of aneurysm risk factors and the suggested hypotheses that connect the different risk factors and the underlying mechanisms governing the aneurysm natural history. The result of this work suggests that at the center of aneurysm evolution there is a cycle of wall degeneration and weakening in response to changing hemodynamic loading and biomechanic stress. This progressive wall degradation drives the geometrical evolution of the aneurysm until it stabilizes or ruptures. Risk factors such as location, genetics, smoking, co-morbidities, and hypertension seem to affect different components of this cycle. However, details of these interactions or their relative importance are still not clearly understood. 相似文献
997.
Ana Elisa von Ah Morano Camila S. Padilha Vinicius Aparecido Matos Soares Fabiana Andrade Machado Peter Hofmann Fabrício E. Rossi Fbio Santos Lira 《Nutrients》2021,13(1)
Background: To investigate the acute effects of a capsaicin analogue supplement on 10 km time-trial performance and physiological responses in amateur athletes. Methods: Twenty-one participants (age = 29.3 ± 5.5 years, weight 74.2 ± 11.3 kg, height 176.0 ± 0.0 cm, fat mass 12.7 ± 3.8%, O2max 62.7 ± 8.4 mL·k−1·min−1), completed two randomized, double-blind trials: capsaicin analogue condition (Capsiate (CAP) = 24 mg) or a placebo (PLA) condition. The participants consumed two doses of 12 mg of CAP or PLA capsule 45 min before and immediately at the start of each trial. The time required to complete 10 km, lactate concentration, maximum heart rate (HRpeak), and rating of perceived exertion (RPE) were recorded. Results: The 10 km time-trial performance (CAP = 45.07 ± 6.41 min vs. PLA = 45.13 ± 6.73, p = 0.828) was not statistically significantly different between conditions. No statistically significant differences between conditions were detected for lactate concentration (p = 0.507), HRpeak (p = 0.897) and RPE (p = 0.517). Conclusion: Two doses of a 12 mg Capsaicin analogue supplement did not improve performance and physiological responses in a 10 km running time-trial in amateur athletes. 相似文献
998.
Pamela Rodrigues Reina Moreira Lais Mendes Vieira Mariana Macedo Costa de Andrade Marcio de Barros Bandarra Gisele Fabrino Machado Danísio Prado Munari Rosemeri de Oliveira Vasconcelos 《Parasitology research》2010,107(3):605-613
The present study aimed to estimate the cell response and parasite load in the popliteal lymph nodes of dogs with visceral
leishmaniasis (VL), comparing these findings with the clinical staging of the disease. From the necropsy, 33 dogs were classified
as symptomatic (S), asymptomatic (A), or oligosymptomatic (O). Cytology and histopathology were used to determine any presence
of microscopic lesions and immunohistochemistry, for parasite load. Dog hyperimmune serum was used as the primary antibody.
The inflammatory infiltrate in lymph nodes consisted of macrophages and plasmocytes. The granulomas invaded the trabecular
and sinusoid regions and sometimes compressed the lymphocytes of the cortical region (atrophy) and medullary cord cells. Parasite
load intensity was unrelated to the density of the macrophages infiltrating the lymph node. Significant differences in parasite
load (P < 0.05) were observed between the three groups of infected dogs. Follicular hyperplasia of the cortical region occurred among
A and O, while follicular atrophy predominated among S. The parasite load was the greatest among S, followed by O. It can
be concluded that, regardless of clinical condition, the most evident cell response consisted of macrophages and plasmocytes.
Lymphoid atrophy was observed among animals with intense granulomatous reaction and high parasite load, such as among the
symptomatic dogs (P < 0.05). Likewise, the oligosymptomatic dogs also presented high density of parasites in the lymph nodes. Thus, we can confirm
that dogs with clinical manifestations of VL have an immune system that is less effective for controlling infection by Leishmania chagasi, thereby favoring parasite multiplication. 相似文献
999.
Mario Tanomaru Filho Guilherme Ferreira da Silva Marco Antonio Húngaro Duarte Marcelo Gon?alves Juliane Maria Guerreiro Tanomaru 《Journal of applied oral science : revista FOB》2008,16(6):376-379
The purpose of this study was to evaluate the radiopacity of 5 root-end filling materials (white MTA-Angelus, grey MTA-Angelus, IRM, Super EBA and Sealer 26). Five specimens (10 mm diameter X 1 mm thickness) were made from each material and radiographed next to an aluminum stepwedge varying in thickness from 2 to 16 mm. Radiographs were digitized and the radiopacity of the materials was compared to that of the aluminum stepwedge using VIXWIN 2000 software in millimeters of aluminum (mm Al). Data were analyzed statistically by ANOVA and Tukey''s test at 5% significance level. Radiopacity values varied from 3 mm Al to 5.9 mm Al. Sealer 26 and IRM presented the highest radiopacity values (p<0.05), while white/grey MTA and Super EBA presented the lowest radiopacity values (p<0.05). The tested root-end filling materials presented different radiopacities, white/grey MTA and Super EBA being the least radiopaque materials. 相似文献
1000.