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991.
This review covers methods and recent developments of the theoretical study of domain structures in ultrathin ferroelectric films. The review begins with an introduction to some basic concepts and theories (e.g., polarization and its modern theory, ferroelectric phase transition, domain formation, and finite size effects, etc.) that are relevant to the study of domain structures in ultrathin ferroelectric films. Basic techniques and recent progress of a variety of important approaches for domain structure simulation, including first-principles calculation, molecular dynamics, Monte Carlo simulation, effective Hamiltonian approach and phase field modeling, as well as multiscale simulation are then elaborated. For each approach, its important features and relative merits over other approaches for modeling domain structures in ultrathin ferroelectric films are discussed. Finally, we review recent theoretical studies on some important issues of domain structures in ultrathin ferroelectric films, with an emphasis on the effects of interfacial electrostatics, boundary conditions and external loads.  相似文献   
992.
Cu electrodeposition was performed on a cylindrical AZ80 substrate with a U-shaped surface. A uniform deposition of Cu was achieved on an AZ80 electrode via galvanostatic etching, followed by Cu electrodeposition in an eco-friendly alkaline Cu plating bath. Improper wetting and lower rotational speeds of the AZ80 electrode resulted in an uneven Cu deposition at the inner upper site of the U-shaped surface during the Cu electroplating process. This wetting effect could be deduced from the variation in the anodic potential during the galvanostatic etching. The corrosion resistance of the Cu-deposited AZ80 electrode can be considerably improved after Ni electroplating.  相似文献   
993.
994.
Peripheral blood-derived inflammation-based scores such as the neutrophil-lymphocyte ratio (NLR) have recently been proposed as prognostic markers in ulcerative colitis. In some previous serological markers are commonly used to detect the severity of the Crohn’s disease (CD), but their sensitivity and specificity are relatively low. So we want to use simple indicators which are easy to obtain to predict disease severity. Now, we investigated and compared the capacity of NLR and other inflammatory markers in detecting CD activity and differentiating CD patients from healthy controls. These CD patients had not received corticosteroid or immunosuppressive drugs within a defined period of time. Data from our hospital between 2010 and 2012 was used. Neutrophil-lymphocyte ratio (NLR), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cells (WBC), platelet count and albumin were measured in 44 patients with active CD, 66 patients with inactive CD, and 55 healthy blood donors. Disease activity was assessed by the Crohn’s Disease Activity Index. In the active CD group, NLR values were found to be elevated compared to inactive CD patients and controls (6.00±7.38, 5.53±6.18 and 1.84±0.85, respectively), but statistical difference was not found between active and inactive CD groups. The overall accuracy of NLR (cutoff: 2.13 fl), CRP (cutoff: 10.5 mg/dl), ESR (cutoff: 19.5 mm/hour) and WBC (cutoff: 9.2 × 109/l) in differentiating CD patients from healthy controls was 80.9%, 67.3%, 71% and 60% respectively. NLR values were found to be correlated with WBC and CRP levels. NLR increased in CD patients compared with healthy subjects. NLR had the best accuracy in determination of CD patients and healthy controls. NLR did not show a discriminative value in disease activity.  相似文献   
995.
This study aimed to determine whether changes in contrast-enhanced computed tomography (CT) parameters could predict postsurgery overall and progression-free survival (PFS) in pancreatic cancer patients. Seventy-nine patients with a final pathological diagnosis of pancreatic adenocarcinoma were included in this study from June 2008 to August 2012. Dynamic contrast-enhanced (DCE) CT of tumors was obtained before curative-intent surgery. Absolute enhancement change (AEC) and relative enhancement change (REC) were evaluated on DCE-CT. PFS and overall survival (OS) were compared based on CT enhancement patterns. The markers of fibrogenic alpha-smooth muscle antigen (α-SMA) and periostin in tumor specimens were evaluated by immunohistochemical staining. The χ2 test was performed to determine whether CT enhancement patterns were associated with α-SMA-periostin expression levels (recorded as positive or negative). Lower REC (<0.9) was associated with shorter PFS (HR 0.51, 95% CI: 0.31–0.89) and OS (HR 0.44, 95% CI: 0.25–0.78). The α-SMA and periostin expression level were negatively correlated with REC (both P = 0). Among several CT enhancement parameters, REC was the best predictor of patient postsurgery survival. Low REC was associated with a short progression-free time and poor survival. The pathological studies suggested that REC might be a reflection of cancer fibrogenic potential.  相似文献   
996.
A large number of long noncoding RNAs (lncRNAs) have been found to be implicated in varieties of tumors. However, the contributions of lncRNAs to tumorigenesis in renal clear cell carcinoma (RCCC) remain largely unknown.We performed a genome-wide analysis of lncRNA expression in RCCC and matched nontumor (NT) tissues to identify new targets for further study of renal carcinoma.The genome-wide analysis of lncRNA expression in 3 RCCC and matched NT tissues were conducted using 4 × 180K Agilent lncRNA Chips and 6 lncRNAs were selected and validated by qRT-PCR in 90 RCCC patients. The differentially expressed lncRNAs and mRNAs were recognized through P value and fold-change (FC) filtering. Potential targets associated with RCCC were identified by gene ontology and pathway analyses. Construction of the co-expression network was accomplished using Cytoscape.A total of 3862 lncRNAs and 2935 mRNAs were deregulated in RCCC tissues, compared with paired NT tissues. PCR results showed the expressions of these 6 lncRNAs were consistent with the chips. Moreover, the co-expression network analysis portended 641 nodes and 571 connections between 109 lncRNAs and 532 coding genes. Lastly, NONHSAT123350 could be involved in the pathogenesis of RCCC and its expression level was closely related to disease-free survival (DFS) and overall survival (OS) in patients without distant metastasis.Our results indicated that these abnormal lncRNAs could respond to renal carcinoma progression and NONHSAT123350 may act as a potential target for future treatment of RCCC.  相似文献   
997.
998.
Thoracoscopic bronchoplasty combined with pulmonary arterial angioplasty can be particularly challenging. In the past, it was often done by using a conventional incision or hybrid video-assisted small incision. In recent years, anecdotal articles have described the application of thoracoscopic bronchoplasty/pulmonary arterial angioplasty. This chapter will describe the details associated with thoracoscopic bronchoplasty/pulmonary arterial angioplasty.  相似文献   
999.
Follistatin is a glycoprotein with various biologic functions that plays a role in adipocyte differentiation, muscle stimulation, anti-inflammation, and energy homeostasis. Thyroid hormones influence energy expenditure, glucose, and lipid metabolism. The association between serum follistatin level and thyroid function statuses has seldom been evaluated.The objectives of this study were to compare serum follistatin concentrations in different thyroid function statuses and to evaluate the associations between serum follistatin and free thyroxine (fT4) levels.In this study, 30 patients with hyperthyroidism (HY group) and 30 euthyroid individuals (EU group) were recruited. The patients of HY group were treated with antithyroid regimens as clinically indicated, whereas no medication was given to EU group. The demographic and anthropometric characteristics, biochemical data, serum levels of follistatin, and thyroid function of both groups at baseline and at the 6th month were compared. Data of all patients were pooled for the analysis of the associations between the levels of follistatin and fT4.At baseline, the HY group had significantly higher serum follistatin levels than the EU group (median [Q1, Q3]: 1.81 [1.33, 2.78] vs 1.13 [0.39, 1.45] ng/mL, P < 0.001). When treated with antithyroid regimens, the follistatin serum levels in HY group decreased to 1.54 [1.00, 1.88] ng/mL at the 6th month. In all patients, the serum levels of follistatin were positively associated with fT4 levels at baseline (β = 0.54, P = 0.005) and at the 6th month (β = 0.59, P < 0.001). The association between follistatin and fT4 levels remained significant in the stepwise multivariate regression analysis, both initially and at the 6th month.In comparison to the EU group, patients with hyperthyroidism had higher serum follistatin levels, which decreased after receiving antithyroid treatment. In addition, the serum follistatin concentrations were positively associated with serum fT4 levels in patients with hyperthyroidism or euthyroidism.  相似文献   
1000.
目的了解宁夏地区朝觐人员乙型肝炎基因分布特点,为探讨宁夏地区朝觐人员乙肝流行趋势提供科学依据。方法采用ELISA法对宁夏地区2010至2012后采用荧光PCR检测方法,对乙肝病毒感染者进行基因分型。结果 90例乙型肝炎HBs Ag阳性者HBV DNA经荧光PCR方法分型,B型5例(5.56%),C型82例(91.11%),其他型3例(3.33%),经统计学分析不同基因型分布有统计学意义;HBV DNA基因型在性别中分布无差异,因此,认为性别与乙肝基因型不具有相关性。结论宁夏地区朝觐人员乙型肝炎患者HBV基因型分布基本符合我国北方的分布特点,以C型为主。  相似文献   
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