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1.
In metastatic breast cancer the goal to reach must be the best possible palliation with minimum discomfort for the patient. We reviewed our experience with radiotherapy (20 or 30 Gy), systemic therapy and brace. Among 2200 breast cancer patients, we extracted 28 potential candidates for resection. All of them developed new metastases outside the treated field within one year. Local control was achieved in 68%, and 80% of them had stable or better performance status at 3 months. From our analysis, even patients with a so called "solitary lesion" do not seem to have a better prognosis than others. We conclude that radiotherapy (with systemic therapy and a brace) is still first-choice treatment for vertebral metastases; CT-guided percutaneous biopsy can avoid worthless major operations. The role of surgery should be limited to neurological compression, severe mechanical instability and to salvage the failures of conservative treatment.  相似文献   
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Immigrant homeowners’ function within ethnic boundaries in the housing market may have helped or hindered them during the recent U.S. Great Recession. This research explores this theme through interviews with immigrant and non-immigrant homeowners from four ethnic communities in Los Angeles County and the non-profit organizations that tried to assist them. Immigrant homeowners turned to co-ethnics for advice and support and formed multigenerational households as a strategy to achieve and sustain homeownership. Language and cultural barriers primed them for risky loans and thwarted their pursuit of refinance and modification when they struggled to make mortgage payments. These findings conform to existing evidence of ethnic segmentation in the housing market and imply that analyses of home buying and homeownership in areas with significant immigrant populations should factor in the role of ethnicity.  相似文献   
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Gui-A-Gra, a commercial insect powder from Gryllus bimaculatus, is registered as an edible insect by the Korean food and drug administration. The aim of this study was to investigate the effect of Gui-A-Gra on testicular damage induced by experimental left varicocele in male Sprague Dawley rats. A total of 72 rats were randomly divided into the following six groups (12 rats in each group): a normal control group (CTR), a group administrated with Gui-A-Gra 1.63 gm/kg (G1.63), a group administrated with Gui-A-Gra 6.5 gm/kg (G6.5), a varicocele (VC)-induced control group (VC), a VC-induced group administrated with Gui-A-Gra 1.63 gm/kg (VC + G1.63), and a VC-induced group administrated with Gui-A-Gra 6.5 gm/kg (VC + G6.5). Rats were administrated 1.63 or 6.5 gm/kg Gui-A-Gra once daily for 42 days. Indicators of sperm parameters, histopathology, reproductive hormones, oxidative stress, endoplasmic reticulum (ER) stress, inflammation, and mitochondrial apoptosis were analyzed to evaluate effects of Gui-A-Gra on VC-induced testicular dysfunction. Gui-A-Gra administration to VC-induced rats significantly (p < 0.05) increased sperm count and sperm motility, Johnsen score, spermatogenic cell density, serum testosterone, testicular superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, GPx4, and steroidogenic acute regulatory protein (StAR) level. Moreover, pretreatment with Gui-A-Gra significantly (p < 0.05) decreased terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) positive cells/tubules, serum luteinizing hormone (LH), serum follicle-stimulating hormone (FSH), testicular tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), malondialdehyde (MDA), reactive oxygen species (ROS)/reactive nitrogen species (RNS) level, glucose-regulated protein-78 (Grp-78), phosphorylated c-Jun-N-terminal kinase (p-JNK), phosphorylated inositol-requiring transmembrane kinase/endoribonuclease 1α (p-IRE1α), cleaved caspase-3, and BCL2 associated X protein: B-cell lymphoma 2 (Bax: Bcl2) ratio in VC rats. These results suggest that protective effects of Gui-A-Gra on VC-induced testicular injury might be due to its antioxidant, anti-inflammatory, and androgenic activities that might be mediated via crosstalk of oxidative stress, ER stress, and mitochondrial apoptosis pathway.  相似文献   
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Serine‐proteinase‐catalyzed peptide splicing was demonstrated in analogues of the trypsin inhibitor SFTI‐1: both single peptides and two‐peptide chains (C‐ and N‐terminal peptide chains linked by a disulfide bridge). In the second series, peptide splicing with catalytic amount of proteinase was observed only when formation of acyl–enzyme intermediate was preceded by hydrolysis of the substrate Lys–Ser peptide bond. Here we demonstrate that with an equimolar amount of the proteinase, splicing occurs in all the two‐peptide‐chain analogues. This conclusion was supported by high resolution crystal structures of selected analogues in complex with trypsin. We showed that the process followed a direct transpeptidation mechanism. Thus, the acyl–enzyme intermediate was formed and was immediately used for a new peptide bond formation; products associated with the hydrolysis of the acyl–enzyme were not observed. The peptide splicing was sequence‐ not structure‐specific.  相似文献   
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The goals of endodontic post and core procedures are to provide maximum retention of the post and resistance to fracture of the roots. Presented is a recently developed fiber composite laminate (FCL) post and core technique which results in a bonded structure that is conservative, morphologic, retentive, versatile, esthetic, and helps resist root fracture. To ascertain the durability of FCL posts and cores, an in vitro pilot study with stress testing is included. The results of the study are compared to other post and core materials to show how well this technique approaches the ideal characteristics for endodontic post and cores.  相似文献   
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Symbolic execution is widely used in many code analysis, testing, and verification tools. As symbolic execution exhaustively explores all feasible paths, it is quite time consuming. To handle the problem, researchers have paralleled existing symbolic execution tools (e.g., KLEE). In particular, Cloud9 is a widely used paralleled symbolic execution tool, and researchers have used the tool to analyze real code. However, researchers criticize that tools such as Cloud9 still cannot analyze large scale code. In this paper, we conduct a field study on Cloud9, in which we use KLEE and Cloud9 to analyze benchmarks in C. Our results confirm the criticism. Based on the results, we identify three bottlenecks that hinder the performance of Cloud9: the communication time gap, the job transfer policy, and the cache management of the solved constraints. To handle these problems, we tune the communication time gap with better parameters, modify the job transfer policy, and implement an approach for cache management of solved constraints. We conduct two evaluations on our benchmarks and a real application to understand our improvements. Our results show that our tuned Cloud9 reduces the execution time significantly, both on our benchmarks and the real application. Furthermore, our evaluation results show that our tuning techniques improve the effectiveness on all the devices, and the improvement can be achieved upto five times, depending upon a tuning value of our approach and the behaviour of program under test.  相似文献   
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The stacking-dependent electronic structure and transport properties of bilayer graphene nanoribbons suspended between gold electrodes are investigated using density functional theory coupled with non-equilibrium Green’s functional method. We find substantially enhanced electron transmission as well as tunneling currents in the AA stacking of bilayer nanoribbons compared to either single-layer or AB stacked bilayer nanoribbons. Interlayer separation between the nanoribbons appears to have a profound impact on the conducting features of the bilayer nanoribbons, which is found to be closely related to the topology and overlap between the edge-localized π orbitals.  相似文献   
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Kinetic studies have been carried out on the esterification of free fatty acids (FFAs) in jatropha oil with methanol in the presence of sulphuric acid catalyst at 5 and 10 wt% concentrations relative to free fatty acids (0.4–0.8 wt% relative to oil) and methanol–FFA mole ratios ranging from 20:1 to 80:1. It has been found that a 60:1 methanol–FFA mole ratio and 5 wt% catalyst at 60°C and 500 rpm or above provided a final acid value lower than 1 mg KOH/g oil within 60 min. A kinetic model has been proposed with second‐order kinetics for both the forward and backward reactions. The effect of temperature on the reaction rate constants and equilibrium constant has been determined using Arrhenius and von't Hoff equations, respectively. The heat of reaction was found to be ?11.102 kJ/mol.  相似文献   
10.
Aneu  Aneu  Wijaya  Karna  Syoufian  Akhmad 《SILICON》2021,13(7):2265-2270
Silicon - Silica-based solid acid catalysts have been successfully prepared and characterized. This research aimed to study the effect of sulfuric acid and calcination temperature on the properties...  相似文献   
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