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961.
Coelho PG Granato R Marin C Teixeira HS Suzuki M Valverde GB Janal MN Lilin T Bonfante EA 《Journal of the Mechanical Behavior of Biomedical Materials》2011,4(8):1974-1981
Implant surface characterization and biomechanical testing were made to evaluate the effect of different surface treatments along with different implant bulk configurations expressed as biomechanical fixation at early implantation times. Three implant surfaces, namely bioactive ceramic electrodeposition (ED), alumina-blasted/acid etched (AB/AE), and resorbable blasting media (RBM) were fabricated in three implant macrogeometries (cylindrical, small chamber, and large chamber). All combinations between surface and bulk configurations were placed in the radii of beagle dogs (n=18), which were euthanized 14 and 40 days after surgery (n=9 animals per time in vivo). The implants were subjected to torque to interface fracture. Effects of time, surface, and macrogeometry on torque to interface fracture were evaluated by a GLM at 95% level of significance. The results showed a significant increase in torque as time elapsed in vivo (p<0.001), and that the ED surface presented significantly higher values compared to AB/AE and RBM (p<0.001) at both times. The small chamber only presented a significantly higher biomechanical fixation compared to other geometries at 40 days in vivo (p=0.02). Biomechanical fixation at 14 and 40 days was affected by implant surface treatment, whereas implant design only affected results at 40 days in vivo. 相似文献
962.
De Marco M Weiner B Meade SA Hadley M Boyd C Goldmon M Green M Manning M Howard DL Godley P Corbie-Smith G 《Journal of the National Medical Association》2011,103(9-10):960-967
We assessed church readiness to engage in health disparities research using a newly developed instrument, examined the correlates of readiness, and described strategies that churches used to promote health. We pilot tested the instrument with churches in a church-academic partnership (n = 12). We determined level of readiness to engage in research and assessed correlates of readiness. We also conducted interviews with participating pastors to explore strategies they had in place to support research engagement. Churches scored fairly high in readiness (average of 4.04 out of 5). Churches with a pastor who promoted the importance of good nutrition in a sermon or had a budget for health-related activities had significantly higher readiness scores than churches without such practices. Having a tool to evaluate church readiness to engage in research will inform targeted technical assistance and research projects that will strengthen church-academic partnerships and improve capacity to address health disparities. 相似文献
963.
Noritomi DT Pereira AJ Bugano DD Rehder PS Silva E 《Clinics (S?o Paulo, Brazil)》2011,66(11):1969-1974
OBJECTIVE:
Intravenous infusion of crystalloid solutions is a cornerstone of the treatment of hemorrhagic shock. However, crystalloid solutions can have variable metabolic acid-base effects, perpetuating or even aggravating shock-induced metabolic acidosis. The aim of this study was to compare, in a controlled volume–driven porcine model of hemorrhagic shock, the effects of three different crystalloid solutions on the hemodynamics and acid-base balance.METHODS:
Controlled hemorrhagic shock (40% of the total blood volume was removed) was induced in 18 animals, which were then treated with normal saline (0.9% NaCl), Lactated Ringer''s Solution or Plasma-Lyte pH 7.4, in a blinded fashion (n = 6 for each group). Using a predefined protocol, the animals received three times the volume of blood removed.RESULTS:
The three different crystalloid infusions were equally capable of reversing the hemorrhage-induced low cardiac output and anuria. The Lactated Ringer''s Solution and Plasma-Lyte pH 7.4 infusions resulted in an increased standard base excess and a decreased serum chloride level, whereas treatment with normal saline resulted in a decreased standard base excess and an increased serum chloride level. The Plasma-Lyte pH 7.4 infusions did not change the level of the unmeasured anions.CONCLUSION:
Although the three tested crystalloid solutions were equally able to attenuate the hemodynamic and tissue perfusion disturbances, only the normal saline induced hyperchloremia and metabolic acidosis. 相似文献964.
How to become immortal: let MEFs count the ways 总被引:1,自引:0,他引:1
965.
966.
967.
An object test was developed to verify the dental images best quality in relation to the exposition time. It consists of high purity perforated aluminum plates, with different thickness and dimensions of 3×4 cm. The plates were covered by acrylic, making its total thickness of 3.0 mm. It was irradiated together with the film from 0.1 to 0.5 s. The irradiation of 0.2 s showed the best image, reducing the regular time exposition by 0.3 s. 相似文献
968.
David C. Markel Renwen Zhang Tong Shi Monica Hawkins Weiping Ren 《Inflammation research》2009,58(7):413-421
Objectives A highly vascularized and inflammatory periprosthetic tissue augments the progress of aseptic loosening, a major clinical
problem after total joint replacement. The purpose of this study is to investigate the effect of erythromycin (EM) on ultra
high molecular weight polyethylene (UHMWPE) particle-induced VEGF/VEGF receptor 1 (Flt-1) gene production and inflammatory
osteolysis in a mouse model.
Methods UHMWPE particles were introduced into established air pouches on BALB/c mice, followed by implantation of calvaria bone from
syngeneic littermates. EM treatment started 2 weeks after bone implantation (5 mg/kg day, i.p. injection). Mice without drug
treatment as well as mice injected with saline alone were included. Pouch tissues were harvested 2 weeks after bone implantation.
Expression of VEGF, Flt-1, RANKL, IL-1, TNF and CD68 was measured by immunostain and RT-PCR, and implanted bone resorption
was analyzed by micro-CT (μCT).
Results Exposure to UHMWPE induced pouch tissue inflammation, increase of VEGF/Flt-1 proteins, and increased bone resorption. EM treatment
significantly improved UHMWPE particle-induced tissue inflammation, reduced VEGF/Flt-1 protein expression, and diminished
the number of TRAP+ cells, as well as the implanted bone resorption.
Conclusion This study demonstrated that EM inhibited VEGF and Flt-1 gene expression. The molecular mechanism of EM action on VEGF/Flt-1
signaling-mediated osteoclastogenesis warrants further investigation. 相似文献
969.
Kerstin Wolk Harald S. Haugen Wenfeng Xu Ellen Witte Kim Waggie Monica Anderson Elmar vom Baur Katrin Witte Katarzyna Warszawska Sandra Philipp Caroline Johnson-Leger Hans-Dieter Volk Wolfram Sterry Robert Sabat 《Journal of molecular medicine (Berlin, Germany)》2009,87(5):523-536
Psoriasis is a common chronic skin disease with a largely unknown pathogenesis. We demonstrate here that transgenic over-expression
of interleukin (IL)-22 in mice resulted in neonatal mortality and psoriasis-like skin alterations including acanthosis and
hypogranularity. This cutaneous phenotype may be caused by the direct influence of IL-22 on keratinocytes, since this cytokine
did not affect skin fibroblasts, endothelial cells, melanocytes, or adipocytes. The comparison of cytokines with hypothesized
roles in psoriasis pathogenesis determined that neither interferon (IFN)-γ nor IL-17, but only IL-22 and, with lower potency,
IL-20 caused psoriasis-like morphological changes in a three-dimensional human epidermis model. These changes were associated
with inhibited keratinocyte terminal differentiation and with STAT3 upregulation. The IL-22 effect on differentiation-regulating
genes was STAT3-dependent. In contrast to IL-22 and IL-20, IFN-γ and IL-17 strongly induced T-cell and neutrophilic granulocyte-attracting
chemokines, respectively. Tumor necrosis factor-α potently induced diverse chemokines and additionally enhanced the expression
of IL-22 receptor pathway elements and amplified some IL-22 effects. This study suggests that different cytokines are players
in the psoriasis pathogenesis although only the IL-10 family members IL-22 and IL-20 directly cause the characteristic epidermal
alterations.
Kerstin Wolk and Harald S. Haugen equally contributed to this work. 相似文献
970.
Marcelo C. Leal Sérgio V. B. Pinheiro erson J. Ferreira Robson A. S. Santos Leonardo S. Bordoni Natalia Alenina Michael Bader Luiz R. França 《Journal of anatomy》2009,214(5):736-743
Evidence regarding the components of the renin–angiotensin (Ang) system suggests that this system plays an important role in male reproduction. However, there are few data available in the literature on the effects of Ang-(1–7) on the male reproductive system. The present study investigated the effects of the genetic deletion and chronic blockage of Ang-(1–7) receptor Mas on spermatogenesis and male fertility. The localization of Mas in mouse and rat testes was determined by binding assays and immunofluorescence, whereas the testis structure and spermatogenic process were morphologically and stereologically analysed by light microscopy. Ang-(1–7) binding and immunofluorescence revealed the presence of Mas in the testes of mice and rats. Although the total numbers of Sertoli and Leydig cells per testis and Leydig cell size were similar in both wild-type and Mas -deficient mice, Mas −/– animals exhibited a significant reduction in testis weight and a greater volume of apoptotic cells, giant cells and vacuoles in the seminiferous epithelium. In both mice and rats, an increased number of apoptotic cells were found during meiosis. Due to disturbed spermatogenesis, daily sperm production was markedly reduced in Mas −/– mice. Moreover, chronic infusion of A-779 [an Ang-(1–7) antagonist] in rats significantly increased the total number of apoptotic cells and primary spermatocytes in particular stages of spermatogenesis. Taken together, these findings strongly suggest that Ang-(1–7) receptor Mas plays an important role in the regulation of spermatogenesis. 相似文献