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991.
992.
Márcio F. Simão Ricardo B. Leite Carlos Rocha M. Leonor Cancela 《Archives of environmental contamination and toxicology》2010,59(3):433-443
A series of artificial microcosms was used to test the effect of clam density on benthic iron biogeochemistry and, subsequently,
if the response of clam Ruditapes decussatus to infection with Perkinsus olseni, a common opportunistic parasite known to be iron dependent, was correlated with the dynamics of iron sediment pore waters
within the chambers. Three series of benthic microcosms were used in the experiment, comparing similar densities of clams
(none, one, two, three, or four individuals/chamber) between a control set (no deliberate infection) and two parallel sets
of clams that were deliberately infected with the parasite after 10 days of incubation. Fifteen chambers were used simultaneously
and the experiment was conducted for 35 days. In order to avoid spurious effects of differential organic loading and clam
feeding efficiency on the oxidative state of the sediment, the iron balance was tentatively shifted during incubation toward
decreased dissolved iron in pore water. This was done by applying a constant flow of air to all chambers and refraining from
supplying extra organic matter during the experimental run, which led to the reduction of benthic oxygen demand as the experiment
progressed. Results showed that microcosms bearing both higher clam densities and lower infection levels were able to exert
a quantitative influence in iron biogeochemistry through bioturbation activity. This effect was significantly depressed in
chambers hosting clams with high infection levels. In addition, analysis of molecular markers responsive to iron and parasite
stress revealed an upper regulation of HSP70 and ferritin in infected clams, thus suggesting a role of those molecules on
both host protection and response to parasite presence by limiting iron availability. Together, these findings suggest a correlation
between the expression of clam molecular iron/stress markers and iron bioavailability, which can be modified by the presence
or absence of Perkinsus infection. In turn, we propose that clam lethargy in response to parasite invasion might help to combat infection by reducing
iron mobilization in the surrounding sediment through a decrease in bioturbation activity, thus reducing its availability
to the parasite. 相似文献
993.
994.
Alessandro Leite Cavalcanti Priscilla Kelly Medeiros Bezerra Catarina Ribeiro Barros de Alencar Cristiano Moura 《Dental traumatology》2009,25(2):198-202
Abstract – The aim of this study was to determine the prevalence and risk factors of dental trauma in the permanent anterior teeth of schoolchildren in Campina Grande, Brazil. A sample of 448 schoolchildren, 228 boys and 220 girls, aged 7–12 years, were randomly selected from 17 public schools in an urban area. The sample selection was carried out in two stages: first, schools were selected by simple sampling and then children were chosen using a proportionality coefficient. Data were collected through clinical examinations and interviews, after examiner calibration. Overjet (OJ) was considered a risk factor when it presented values higher than 3 mm, while lip coverage was classified as adequate or inadequate. Yates' chi-squared test verified the association between the variables and odds ratio. Significance level was set at 5%. The prevalence of dental injuries was 21%. Boys experienced more injuries than girls, 21.9% and 20%, respectively ( P > 0.05). Falls and collisions were the main causes of dental trauma, 63.8% and 24.5%, respectively. There was a statistically significant difference between traumatic dental injuries (TDI) and OJ (95% CI 0.22–0.63) ( P < 0.001) and between TDI and inadequate lip coverage (95% CI 9.16–34.93) ( P < 0.001). Data indicated that boys presenting an OJ size >3 mm and inadequate lip coverage were more likely to have TDI in Campina Grande, Brazil. 相似文献
995.
Rodrigues Cleonisio Leite de Freitas Hermany Capistrano Lima Paulo Reges Oliveira de Oliveira Junior Pedro Helder Fernandes José Marcelino Aragão D’Almeida José Artur Costa Nóbrega Paulo Ribeiro 《Neurological sciences》2022,43(4):2271-2276
Neurological Sciences - Myasthenia gravis (MG) is an autoimmune disorder of the neuromuscular junction that can be exacerbated by many viral infections, including COVID-19. The management of MG... 相似文献
996.
Freitas ES Leite ED Souza CA Ocarino NM Ferreira E Cassali GD Gomes MG Serakides R 《Reproduction, fertility, and development》2007,19(3):498-509
In two different experiments, the effects of hyperthyroidism on the histomorphometry and expression of Cdc47 and caspase-3 were evaluated in the uteri and placentas during gestation and postpartum. Fetal development was also evaluated during gestation. In the first experiment, 36 adult female Wistar rats were divided into two groups of 18 animals each: (1) hyperthyroid; and (2) euthyroid (control). Female rats were mated and killed at 7, 14 and 19 days of gestation. Uteri and placentas were weighed and subjected to histomorphometric and immunohistochemical evaluation to determine the expression of Cdc47 and caspase-3. Ovaries were also evaluated for weight and subjected to morphometric analysis. Fetuses were quantified and weighed individually. In the second experiment, 12 adult female Wistar rats were divided into two groups of six animals each: (1) hyperthyroid; and (2) euthyroid (control). Female rats were mated and killed 2 days postpartum. Uteri were evaluated in the same way as for the first experiment. Hyperthyroidism increased ovulation and conception rates without disturbing the size and viability of the fetuses. In the pregnant uteri, hyperthyroidism did not change the thickness of the layers or the expression of Cdc47 and caspase-3. However, in the placentas, hyperthyroidism increased the medium diameter of trophoblast cells, as well as the thickness and the expression of Cdc47 of spongiotrophoblast cells, at 14 days of gestation. During uterine involution, hyperthyroidism significantly increased the expression of Cdc47 and reduced the expression of caspase-3 in the uterine layers. In conclusion, hyperthyroidism increased the conception rate because of an ovulation gain, induced significant placental changes during pregnancy and, in the uterus, increased Cdc47 expression and decreased caspase-3 expression after parturition. 相似文献
997.
Caperuto EC Tomatieli RV Colquhoun A Seelaender MC Costa Rosa LF 《Clinical nutrition (Edinburgh, Scotland)》2007,26(1):117-122
BACKGROUND & AIMS: Cancer cachexia affects intermediary metabolism with intense and general catabolism. Walker 256 tumor is a model injected either subcutaneously (Sc) or intraperitoneally (Ip), with different metabolic features. Beta-hydroxy beta-methylbutyrate (HMbeta) is a leucine metabolite with anti-catabolic properties, the aim of this study being to investigate its effects on metabolic parameters in both tumor models. METHODS: Controls (subcutaneous control group (ScC) and intraperitoneal control group (IpC)) and supplemented animals (subcutaneous supplemented group (ScS) and intraperitoneal supplemented group (IpS)) showed these results. RESULTS: Protein Sc values were (47.8%) lower than Ip groups. Sc group fat content was (65.16%) higher than Ip groups. Liver glycogen value for Sc groups was (38.4%) higher than Ip groups. Muscle glycogen value for Sc groups were (2.75 times) higher than Ip groups. Corticosterone and insulin values were lower (44.53%) and higher (45.94%), respectively, in Sc when compared with Ip groups. Glucose and lactate values for ScS were the lowest (61.7% and 41.53%) compared to other groups. ScC glutamine value was the highest (40.8%) of all groups. Glutamate Sc values were (42.65%) lower than Ip groups. Sc groups showed greater survival time compared with Ip groups. ScS group showed 100% increase in survival time when compared with ScC. CONCLUSIONS: HMbeta supplementation can increase survival time and promotes metabolic changes in cancer-bearing animals, but it seems to work in a time-dependent manner. 相似文献
998.
Figueiredo Mdo L Tyrrel MA de Carvalho CM Luz MH Amorim FC Loiola NL 《Revista brasileira de enfermagem》2007,60(4):422-427
Qualitative study that aimed at investigating present and decisive gender subjects of health and elder people's life quality. The subjects were 20 (twenty) seniors of the Programa Terceira Idade em A??o-PTIA. The semi-structured interview was used as data collection technique. From the speeches, information that answered the investigation inquietudes emerged and they made possible the formulation of three analysis categories. In the first, it stood out the low self-esteem lived by the men when they age, otherwise in the second one it was evidenced the autonomy and the freedom conquered by the senior women, and in the third category the learning happened among the old ladies who participated of PTIA. Concluding that there is influence of the gender subjects in health and life quality in aging. 相似文献
999.
The study presents some trajectory highlights of the Center of Studies and Research in Nursing of the Brazilian Nursing Association, considering the period from 1971 to 2007. This is a historical study based on the Information Catalog of Research and Researchers in Nursing and the reports of the National Seminars of Nursing Research. The objectives were to rescue the contribution of CEPEn and to present one of the most important events for Brazilian Nursing. The concern with the future and the need for empowerment and enrichment, of professors as well as for assistance professionals, is one of the marks in nowadays and it is a challenge to be faced in present time. 相似文献
1000.
In vitro characteristics of white cell-reduced single-unit platelet concentrates stored in syringes 总被引:1,自引:0,他引:1
PT Pisciotto ; EL Snyder ; JA Snyder ; S Frattaroli ; SM Hopfer ; HM Rinder ; BR Smith 《Transfusion》1994,34(5):407-411
BACKGROUND: Platelet concentrates (PCs) for premature infants may be subjected to filtration, centrifugation, and various storage conditions before transfusion. STUDY DESIGN AND METHODS: As there are few data on the cumulative effect of these procedures on PCs, platelet properties (including biochemical and functional in vitro assays) were evaluated after the processing of single units of PCs through a 1-unit-capacity high-efficiency white cell (WBC)-reduction filter followed by syringe storage at either 22 or 37 degrees C for 6 hours. Two- and 5-day-old PCs, volume-reduced PCs, and prestorage WBC-reduced PCs were evaluated. RESULTS: WBC filtration consistently resulted in a 3 to 4 log10 reduction in WBCs, with less than 15-percent platelet loss. No adverse effects of platelet function or evidence of increased platelet activation as determined by the percentage of P-selectin positivity were noted. A decrease in pH associated with increased lactate production and consumption of glucose was observed following syringe storage under all conditions tested. Such changes were most pronounced, however, with volume-reduced PCs stored at 37 degrees C (pH 6.31 +/− 0.15, lactate 23.0 +/− 3.06 mmol/L). All pH levels at the end of storage were above the minimum Food and Drug Administration requirement (pH 6.0). CONCLUSION: The in vitro data suggest that single units of PCs can undergo WBC filtration followed by syringe storage for up to 6 hours and still maintain acceptable storage characteristics. The practice of maintaining volume-reduced PCs in syringes for 6 hours at 37 degrees C in isolettes during transfusion should, however, be avoided. 相似文献