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961.
Features of papillary thyroid microcarcinoma associated with lateral cervical lymph node metastasis
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962.
Christoph F. Dietrich Adrian Goudie Liliana Chiorean Xin Wu Cui Odd Helge Gilja Yi Dong Jacques S. Abramowicz Sudhir Vinayak Susan Campbell Westerway Christian Pállson Nolsøe Yi-Hong Chou Michael Blaivas 《Ultrasound in medicine & biology》2017,43(1):49-58
Over the last decade, the use of portable ultrasound scanners has enhanced the concept of point of care ultrasound (PoC-US), namely, “ultrasound performed at the bedside and interpreted directly by the treating clinician.” PoC-US is not a replacement for comprehensive ultrasound, but rather allows physicians immediate access to clinical imaging for rapid and direct solutions. PoC-US has already revolutionized everyday clinical practice, and it is believed that it will dramatically change how ultrasound is applied in daily practice. However, its use and teaching are different from continent to continent and from country to country. This World Federation for Ultrasound in Medicine and Biology position paper discusses the current status and future perspectives of PoC-US. Particular attention is given to the different uses of PoC-US and its clinical significance, including within emergency and critical care medicine, cardiology, anesthesiology, rheumatology, obstetrics, neonatology, gynecology, gastroenterology and many other applications. In the future, PoC-US will be more diverse than ever and be included in medical student training. 相似文献
963.
964.
Zhaohui Wang Yu-Hua Liao Jing Yuan Jing-Hui Zhang Zhong-Ping Liu Ji-Hua Dong 《Autoimmunity》2013,46(6):455-460
T-cell immune abnormality in patients of dilated cardiomyopathy has been intensively studied over the past 10 years. In this study, we aim to focus on the molecular mechanism of T-cells in autoimmune cardiomyopathy mouse model by detecting the expression of three T-cell signaling molecules. Balb/C mice (n = 12) were immunized with the peptides derived from human ADP/ATP carrier on the 1st, 14th, 28th, 49th and 79th days, and half of them were also injected with anti-L3T4 McAb on the ? 1st, 0 and 1st days. The sham-immunized mice were taken as the controls (n = 6). The main result shows that the antibody response of IgG subclasses such as IgG1, IgG2b and IgG3 were definitely blocked except IgG2a in CD4+ cell-depleted Balb/C mice. In addition, the average mRNA expression of p56lck, p59fyn and zap-70 were all found to be dramatically higher in the mice immunized with only ADP/ATP carrier peptides than in the control-group. At meantime, reduced levels of the protein kinases p56lck, p59fyn and zap-70 were clearly observed in anti-CD4 McAb immunized group compared with DCM group. We propose that the proliferation of T-cells was significantly inhibited in anti-CD4 treated mice and CD4+ T-cells may play a critical role in ADP/ATP carrier caused mouse DCM. 相似文献
965.
XuanQi Zheng JinFeng Huang JiaLiang Lin DeJun Yang TianZhen Xu Dong Chen 《Journal of biomaterials science. Polymer edition》2013,24(13):1172-1187
AbstractThe repair of critical-size bone defect remains a challenge for orthopedic surgeons. With the advent of an aging society and their accompanying chronic diseases, it is becoming more difficult to treat bone defects, especially large segmental bone defects that are caused by trauma, tumors, infections, and congenital malformations. New materials and technologies need to be developed to address these conditions. 3D bioprinting is a novel technology that bridges the biomaterial and living cells and is an important method in tissue engineering projects. 3D bioprinting has the advantages of replacing or repairing damaged tissue and organs. The progress in material science and 3D printing devices make 3D bioprinting a technology which can be used to create various scaffolds with a large range of advanced material and cell types. However, in regard to the widespread use of bioprinting, biosafety, immunogenicity and rising costs are rising to be concerned. This article reviews the developments and applications of 3D bioprinting and highlights newly applied techniques and materials and the recent achievements in the orthopedic field. This paper also briefly reviews the difference between the methods of 3D bioprinting. The challenges are also elaborated with the aim to research materials, manufacture scaffolds, promote vascularization and maintain cell viability. 相似文献
966.
Fan Zhang Wenqing Zhao Wenling Li Changzheng Dong Xinying Zhang Jiang Wu Na Li Chuandong Liang 《中国神经再生研究》2013,8(17):1597-1605
Exogenous neuropeptide Y has antiepileptic effects; however, the underlying mechanism and optimal administration method for neuropeptide Y are still unresolved. Previous studies have used intracerebroventricular injection of neuropeptide Y into animal models of epilepsy. In this study, a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene was injected into the lateral ventricle of rats, while the ipsilateral hippocampus was injected with kainic acid to establish the epileptic model. After transfection of neuropeptide Y gene, mossy fiber sprouting in the hippocampal CA3 region of epileptic rats was significantly suppressed, hippocampal synaptophysin (p38) mRNA and protein expression were inhibited, and epileptic seizures were reduced. These experimental findings indicate that a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene reduces mossy fiber sprouting and inhibits abnormal synaptophysin expression, thereby suppressing post-epileptic synaptic reconstruction. 相似文献
967.
A Non-Ersatz Material Approach for the Topology Optimization of Elastic Structures Based on Piecewise Constant Level Set Method
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Zhengfang Zhang Yanqiang Dong & Weifeng Chen 《Communications In Computational Physics》2021,30(5):1370-1389
The topology optimization of a linearized elasticity system with the area
(volume) constraint is investigated. A non-ersatz material approach is proposed. By
introducing a fixed background domain, the linearized elasticity system is extended
into the background domain by a characteristic function. The piecewise constant level
set (PCLS) method is applied to represent the original material region and the void
region. A quadratic function of PCLS function is proposed to replace the characteristic
function. The functional derivative of the objective functional with respect to PCLS
function is derived, which is zero in the void region and nonzero in the original material region. A penalty gradient algorithm is proposed. Four numerical experiments of
2D and 3D elastic structures with different boundary conditions are presented, illustrating the validity of the proposed algorithm. 相似文献
968.
The multi-scan resting state fMRI (rs-fMRI) dataset was recently released; thus the test-retest (TRT) reliability of rs-fMRI measures can be assessed. However, because this dataset was acquired only from a single group under a single condition, we cannot directly evaluate whether the rs-fMRI measures can generate reproducible between-condition or between-group results. Because the modulation of resting state activity has gained increasing attention, it is important to know whether one rs-fMRI metric can reliably detect the alteration of the resting activity. Here, we shared a public Eyes-Open (EO)/Eyes-Closed (EC) dataset for evaluating the split-half reproducibility of the rs-fMRI measures in detecting changes of the resting state activity between EO and EC. As examples, we assessed the split-half reproducibility of three widely applied rs-fMRI metrics: amplitude of low frequency fluctuation, regional homogeneity, and seed-based correlation analysis. Our results demonstrated that reproducible patterns of EO-EC differences can be detected by all three measures, suggesting the feasibility of the EO/EC dataset for performing reproducibility assessment for other rs-fMRI measures. 相似文献
969.
An-Qin Vicky Dong 《Developmental neurorehabilitation》2016,19(5):275-283
Objective: To investigate the effects of ‘remind to move’ treatment on hemiplegic arm function in children with unilateral cerebral palsy (CP). Methodology: Twelve students with unilateral CP aged 6–18 were recruited from a special school and randomly assigned into two groups. Participants in the experimental group underwent a 3-week sensory cueing treatment followed by a 3-week sham treatment. Participants in the waitlist group completed the sham treatment first followed by the sensory-cueing treatment. There was a 4-week washout period between treatments. Results: Both functional hand use and arm impairment level significantxly improved after the 3-week sensory cueing treatment for the combined sample between groups. However, no significant carryover effects were found for either treatment. Conclusion: Three weeks of ‘remind to move’ treatment is useful in improving hemiplegic arm function and quantity of hand use in children with unilateral CP but the long-term carryover effect requires further investigation. 相似文献
970.
目的研究0~3岁不同性别、不同年龄组儿童骨密度状况,为监测儿童钙营养和骨健康提供依据。方法随机抽取在儿童保健门诊进行健康体检的的4551名0~3岁健康儿童进行超声骨密度检测,根据同年龄、同性别骨密度Z值的评分数分为正常、轻度不足、中度不足、重度不足。结果男童骨密度Z值高于女性,骨密度不足检出率女童高于男童,不同性别间比较差异有统计学意义(χ2=102.11,P0.001);年龄越小,骨密度不足检出率越高。不同年龄组儿童骨密度值比较差异有显著性(χ2=595.35,P0.001)。结论 1岁之内的婴儿是防治骨密度不足的主要人群,生后6个月婴儿是防治骨密度不足的关键期。 相似文献