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Neurocognitive outcome affects the quality of life of ALL survivors. This study is aimed to assess the prevalence of neurocognitive dysfunction by psychometric and imaging tools in survivors of childhood ALL, treated with 3 different protocols and the effect of time elapsed since the end of chemotherapy. Sixty-two ALL survivors aged 6–18 years and treated in the period 1997–2007 and 60 healthy age and sex matched controls were subjected to neurocognitive testing using Wechsler Intelligence Scale for Children, Benton visual retention (BVRT) and Trail Making test (TMT), followed by diffusion weighed and diffusion tensor MRI for calculation of fraction anisotropy (FA). Survivors underwent revision of protocol and type of CNS therapy. Three different protocols were used: modified BFM 83, BFM 90, and CCG. Survivors treated with modified CCG protocol showed a significant decrease in all cognitive tests compared to control (p<.05); BFM 90 group had a significant lower IQ and longer TMT compared to both control and BFM 83 group and no significant difference was found in results of cognitive tests between BFM 83 and control group. Frontal FA was lower in CCG treated group compared to control, BFM 90 and BFM 83 groups (p<.05); meanwhile it was significantly lower in BFM 90 and BFM 83 groups compared to control group. We concluded that patients treated with modified CCG protocol showed the worst neurocognitive outcome among three assessed protocols. Frontal lobe FA might be an early marker for predicting the neurotoxicity in childhood ALL survivors.  相似文献   
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The use of metal additive manufacturing (AM) has strongly increased in the industry during the last years. More specifically, selective laser melting (SLM) is one of the most used techniques due to its numerous advantages compared to conventional processing methods. The purpose of this study is to investigate the effects of process parameters on the microstructural and corrosion properties of the additively manufactured AISI 316L stainless steel. Porosity, surface roughness, hardness, and grain size were studied for specimens produced with energy densities ranging from 51.17 to 173.91 J/mm3 that resulted from different combinations of processing parameters. Using experimental results and applying the Taguchi model, 99.38 J/mm3 was determined as the optimal energy density needed to produce samples with almost no porosity. The following analysis of variance ANOVA confirmed the scanning speed as the most influential factor in reducing the porosity percentage, which had a 74.9% contribution, followed by the position along the building direction with 22.8%, and finally, the laser energy with 2.3%. The influence on corrosion resistance was obtained by performing cyclic potentiodynamic polarization tests (CPP) in a 3.5 wt % NaCl solution at room temperature for different energy densities and positions (Z axis). The corrosion properties of the AM samples were studied and compared to those obtained from the traditionally manufactured samples. The corrosion resistance of the samples worsened with the increase in the percentage of porosity. The process parameters have consequently been optimized and the database has been extended to improve the quality of the AM-produced parts in which microstructural heterogeneities were observed along the building direction.  相似文献   
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The entries of pathogenic bacteria into the human body remain a severe problem to health that can be prevented using antibacterial agents. Meanwhile, the photocatalytic technique using semiconductor nanocomposite TiO2–SiO2 has great potential as an antibacterial method. In order to utilize natural resources, SiO2 supporting materials are obtained from the extraction of beach sand due to the high silica content. Therefore, this study aims to synthesize a nanocomposite of TiO2 with SiO2 extracted from beach sand as an antibacterial agent against Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial activity test used the dilution and optical density method. Based on XRD analysis, the crystals of TiO2 in the synthesized composites showed a more dominant anatase structure. Furthermore, Ti–O–Si bonds were identified from the IR spectrum, which showed the interaction between TiO2 and SiO2. In addition, SEM-EDX results showed agglomerated spherical particles with a TiO2–SiO2 nanocomposite particle size of 40–107 nm. The best antibacterial activity was demonstrated by the 1 : 0.5 TiO2–SiO2 nanocomposite, with inactivation percentages of S. aureus and P. aeruginosa of 98.69% and 97.44%, respectively.

TiO2 material is composited with silica obtained from natural sand with indirect sonochemistry method. The addition of SiO2 increase the photocatalyst activity of TiO2 as an antibacterial against S. aureus and P. aeruginosa.  相似文献   
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Abstract

Endometriosis is one of the most common gynecological diseases and a major cause of pain and infertility. It is influenced by genetic, epigenetic, and environmental factors. Recently, genome-wide association studies have revealed a strong association between IL1A single nucleotide polymorphisms (SNPs) and increased risk of endometriosis in Japanese women. The aim of the present study was to evaluate the association of three IL1A SNPs, rs17561, rs1304037, and rs2856836 with the risk of endometriosis in Iranian population. Totally, 105 women with diagnosis of endometriosis and 102 healthy women as control group were included. Three SNPs of the IL1A, rs17561?G/T, rs1304037 A/G, and rs2856836 T/C, were genotyped by PCR and RFLP. The rs2856836?TC genotype was significantly higher (p?=?.002; OR?=?3.1, 95% CI: 1.5–6.5) in the patients (28.1%) than the control group (12.7%). The rs2856836?CC genotype was significantly higher (p?=?.047; OR?=?2.3, 95% CI: 1.0–5.3) in the patients (17.5%) than the control group (10.8%). The rs2856836 C allele was significantly higher (p?=?.001; OR?=?2.2, 95% CI: 1.4–3.6) in the patients (31.6%) than the control group (17.2%). The IL1A rs2856836 T/C SNP was associated with susceptibility to endometriosis and the rs2856836 C allele may increase the risk of endometriosis in Iranian women.  相似文献   
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Advanced melanoma patients who failed anti-PD-1 therapy have limited options. We analyzed a cohort of 133 advanced melanoma patients receiving anti-PD-1 monotherapy in a referral center between April 2015 and December 2017, and included the 26 patients with confirmed progressive (PD) or stable disease who received additional radiotherapy with an unmodified anti-PD-1 mAb regimen. Tumor evaluations were done on radiated and nonradiated (RECIST 1.1) lesions, with abscopal effect defined as a partial (PR) or complete response (CR) outside radiated fields. Primary endpoint was the CR + PR rate in radiated + nonradiated lesions. Secondary endpoints were progression-free survival (PFS), melanoma-specific survival (MSS) and safety. First late radiotherapy, consisting of hypofractionated radiotherapy (3–5 sessions, 20–26 Gy), standard palliative radiotherapy or brain radiosurgery was begun after a median of 6.3 months of anti-PD-1 in 23, 2 and 1 patient(s), respectively. Best response was 8 (31%) CR, 2 (8%) profound PR allowing surgical resection of remaining metastases and 16 (62%) PD. Abscopal effect was seen in 35% of patients. Median PFS and MSS since anti-PD-1 initiation was 15.2 [95% CI: 8.0 not achieved (na)] and 35.3 [95% CI: 18.5 na] months, respectively. PFS curves seemed to achieve a plateau. We discontinued anti-PD-1 therapy in 9/10 of patients with no residual evaluable disease and observed one relapse after a median of 10 months off anti-PD1-therapy. No unusual adverse event was recorded. Limitations of the study include its retrospective nature and limited size. Hypofractionated radiotherapy may enhance anti-PD1 monotherapy efficacy in patients who previously failed anti-PD-1 therapy. Controlled studies are needed.  相似文献   
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