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Maternal and Child Health Journal - Mothers are especially vulnerable to the onset or recurrence of psychological symptoms during the postpartum period. However, protective psychosocial factors may...  相似文献   
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Metastases to vertebrae often cause bone destruction leading to instability and neural compression. Anterior surgical approaches allow tumor resection and direct neural decompression. For patients with a short life expectancy, vertebral body replacement with methyl-methacrylate polymerized in situ can be used for load sharing in the axial plane. Screws hung from the rod into the corpectomy site are incorporated into the acrylic cement. The technique described in this article allows for immediate spinal stabilization and provides a protective environment for the neural elements. All the patients tolerated the procedure well and were able to ambulation without an orthoses.  相似文献   
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ObjectivesTo describe and apply a method of modelling dental crowns and three-unit fixed partial dentures (FPD) for finite element analyses (FEA) from 3D images obtained using a micro-CT scanner.MethodsA crown and a three-unit fixed partial denture (FPD) made of a ceramic framework (Y-TZP) and veneered with porcelain (VM9) were scanned using an X-ray micro-CT scanner with a pixel size of 6.97 μm. Slice images from both structures were generated at each 0.034 mm and processed by an interactive image control system (Mimics). Different masks of abutments, framework and veneer were extracted using thresholding and region growing tools based on X-ray image brightness and contrast. 3D objects of each model were incorporated into non-manifold assembly and meshed simultaneously. Volume meshes were exported to the FEA software (ABAQUS), and the load-generated stress distribution was analyzed.ResultsFEA models showed great shape resemblance with the structures. The use of non-manifold assembly ensured matching surfaces and coinciding nodes between different structural parts. For the crown model, tensile stresses were concentrated in the internal surface of the core, near to the applied load. For the FPD model, the highest tensile stresses were located in the framework, on the cervical area of connectors and pontic.ConclusionsValid 3D models of dental crown and FPD can be generated by combining micro-CT scanning and Mimics software, emphasizing its importance as design tool in dental research.Clinical significanceThe 3D FEA method described in this work is an important tool to predict the stress distribution, assisting on structural design of dental restorations.  相似文献   
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Clinical Rheumatology - The American Academy of Ophthalmology (2016-AAO) recommended hydroxychloroquine (HCQ) dose not to exceed 5 mg/kg/day (real body weight). Recently, it was reported that...  相似文献   
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RationalTherapeutic Plasma Exchange (TPE) procedures in pediatric patients are challenging due to the large extracorporeal volume of the cell separators, which were designed for adults. Red blood cell (RBC) priming is an alternative for overpassing the risks of hypovolemia, but data referring to the volume of packed RBCs to be infused are yet incomplete. Restricting the volume of RBC priming may potentially be associated with less transfusion reactions.GoalTo determine the safety of administering a reduced volume of RBC priming for pediatric patients undergoing TPE, in comparison to the standard volume recommended by the cell separators’ manufacturers.MethodsThis was a case-control study which enrolled 15 pediatric patients undergoing TPE and weighting more than 10Kg. The TPE procedures (n = 406) were divided in two groups: 1) Group1: TPE with ≤150 mL of packed RBC priming and 2) Group2: TPE with 150-250 mL of RBC priming. Groups were compared in terms of hemoglobin / hematocrit and occurrence of adverse reactions.ResultsGroup1 and Group2 did not differ significantly in relation to pre- and post-TPE hemoglobin (Hb) levels (p = 0.19 and p = 0.18, respectively). The Δ Hb (Hb pre-TPE – Hb post-TPE) was also not statistically different between the groups. The number of adverse reactions was significantly higher in Group 2 in relation to Group 1 (p = 0.01). The number of allergic reactions was also higher in Group 2 (p = 0.06).ConclusionsRestricting the volume of RBC priming to less than 150 mL is safe for pediatric patients weighting more than 10Kg and associated with lower rates of transfusion-related adverse reactions.  相似文献   
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Statement of problemRestorative materials are cemented on different types of substrates, such as dentin, metal, and glass-fiber posts with composite resin cores.PurposeThe purpose of this in vitro study was to evaluate the failure behavior after cycling fatigue of a polymer-infiltrated ceramic network material (PICN; VITA ENAMIC) cemented on different supporting substrates.Material and methodsPICN plates (N=80) were obtained from computer-assisted design and computer-assisted manufacturing (CAD-CAM) blocks and cemented with a resin cement to 4 different supporting substrates (n=20): (1) human dentin (PICNDen); (2) dentin analog (PICNDenAn); (3) nickel-chromium alloy (PICNNiCr); and (4) composite resin plus fiberglass post (PICNRc). For comparison, the fracture behavior of a feldspathic ceramic (FelDenAn; VITABLOCS Mark II) and an indirect composite resin (ResDenAn; Opallis LAB Resin) cemented to the DenAn substrate was investigated (n=20). Thus, specimens were composed of the restorative material layer (1-mm thick) resin cemented (0.1-mm-thick layer) to a 2-mm-thick supporting substrate. All specimens were subjected to mechanical cycling (MC) using a pneumatic cycling machine (500 000 cycles, 2 Hz, 50 N). Specimens that did not fracture during cycling were tested under compression using a universal testing machine at a cross-head speed of 0.5 mm/min until the sound of the first crack was detected using an acoustic system. Failure data were statistically evaluated using Weibull distribution. Failures were classified as radial crack, cone crack, combined, and catastrophic fracture.ResultsAll FelDenAn specimens were fractured during MC. Only 4 PICNRc specimens survived MC, so their fracture load data were not statistically analyzed. PICNNiCr showed the greatest characteristic load (L0) value, followed by ResDenAn. Groups PICNDenAn and PICNDen showed lower and similar L0 but statistically different Weibull modulus (m). There was a significant relationship between experimental group and failure mode (P<.001). FelDenAn and PICNRc had a higher frequency of radial cracks, whereas PICNNiCr failed from cone cracking.ConclusionsThe supporting substrate influenced the failure behavior of PICN. When the substrate had a higher elastic modulus than the restorative material, better mechanical behavior was observed.  相似文献   
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This paper chronicles a 2-year-old girl who presented with acute leukemia/lymphoma syndrome of the T cell immunophenotype. At this time, the cytogenetic analysis of her bone marrow cells showed a reciprocal translocation between the short arm of chromosome 12 and the long arm of chromosome 13, t(12;13)(p13;q14). The immunophenotyping of bone marrow blast cells by flow cytometry revealed a population of cells positive for CD56, CD117, CD45, partial CD33, partial HLA-DR, CD13, CD7, CD2 and CD5. Therefore, a diagnosis of acute leukemia with a mixed T cell/myeloid phenotype was made. The patient had a poor response to classic T cell acute lymphocytic leukemia/lymphoma therapy; thus, her treatment was changed to a myeloid leukemia protocol, which produced a good response. She underwent a successful cord blood transplantation from an unrelated HLA partially matched donor. The coexistence of these two phenotypes prompts questions about the existence of clonal instability, which might influence the choice of therapy. The rarity of the t(12;13)(p13;q14) and the coexistence of T cell/myeloid markers suggest a nonrandom association. To the best of our knowledge, this is the first reported case in which a cell clone bearing a t(12;13)(p13;q14) translocation in a mixed T cell/myeloid lesion was detected.  相似文献   
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