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81.
Chien-Tai Huang Chien-Hao Lin Hsiu-Po Wang Wan-Ching Lien 《Hemodialysis international. International Symposium on Home Hemodialysis》2022,26(1):E5-E7
Spontaneous spinal epidural hematoma (SEH) is extremely rare in patients with end-stage renal disease (ESRD). We report a case of a 71-year-old man with ESRD presented with progressive left limb weakness. Magnetic resonance imaging (MRI) revealed spinal cervical SEH involving C3-5 level. The patient received emergent decompression laminectomy with the evacuation of the epidural hematoma. 相似文献
82.
褚希 《机械工程与自动化》2012,(3):171-172
介绍了二项式控制方式的原理与应用.在热轧粗轧短行程过程中,二项式控制方式的应用可以大幅度减少轧件端部的“鱼尾”状形变,优化控制曲线,减少端部剪切量,增加经济效益. 相似文献
83.
《核技术(英文版)》2016,(6):159-162
An improved thermometer (TIB) is proposed for intermediate-mass fragments via the difference between isobaric yield ratios. The residual free energy of three isobars is replaced by that of the binding energy. The measured fragments in the 140A MeV 40, 48Ca+ 9Be (181Ta) and 58, 64Ni+ 9Be (181Ta) reactions are analyzed to obtain TIB ranging from 0.6 to 3.5 MeV. TIB is suggested to be a direct determination of temperature avoiding the fit-ting procedure. 相似文献
84.
Andreas Kiermeier Mark Tamplin Damian May Geoff Holds Michelle Williams Alison Dann 《Food microbiology》2013
Packaging fresh lamb in a vacuum (VAC) versus a 100% CO2 modified atmosphere (MAP) may influence product shelf-life and the bacterial communities. While VAC is a common packing method and 100% CO2 MAP is used in some countries, there is little information about how these different techniques affect the growth of spoilage bacteria and sensory attributes of lamb. The aim of this study was to assess changes in microbiological and organoleptic properties, and determine differences in microbial communities by terminal restriction fragment length polymorphism (TRFLP) and 454 pyrosequencing, in bone-in (BI) and bone-out (BO) MAP- and VAC-packed lamb shoulders stored at −0.3 °C over 12 wk. VAC and MAP lamb shoulders were acceptable in sensory test scores over 12 wk of storage at −0.3 °C, despite total viable count (TVC) and lactic acid bacteria (LAB) levels increasing to 8 log10 CFU/cm2 for VAC lamb and 4–6 log10 CFU/cm2 for MAP lamb. Similar to the sensory results, there were no significant differences in microbial communities between BI and BO product. However, types of bacteria were different between VAC and MAP packaging. Specifically, while VAC shoulder became dominated by Carnobacterium spp. in the middle of the storage period, the MAP shoulder microbial population remained similar from the start until later storage times. 相似文献
85.
Balder Lai Christoph Hasenhindl Christian Obinger Chris Oostenbrink 《International journal of molecular sciences》2014,15(1):438-455
An interesting format in the development of therapeutic monoclonal antibodies uses the crystallizable fragment of IgG1 as starting scaffold. Engineering of its structural loops allows generation of an antigen binding site. However, this might impair the molecule’s conformational stability, which can be overcome by introducing stabilizing point mutations in the CH3 domains. These point mutations often affect the stability and unfolding behavior of both the CH2 and CH3 domains. In order to understand this cross-talk, molecular dynamics simulations of the domains of the Fc fragment of human IgG1 are reported. The structure of human IgG1-Fc obtained from X-ray crystallography is used as a starting point for simulations of the wild-type protein at two different pH values. The stabilizing effect of a single point mutation in the CH3 domain as well as the impact of the hinge region and the glycan tree structure connected to the CH2 domains is investigated. Regions of high local flexibility were identified as potential sites for engineering antigen binding sites. Obtained data are discussed with respect to the available X-ray structure of IgG1-Fc, directed evolution approaches that screen for stability and use of the scaffold IgG1-Fc in the design of antigen binding Fc proteins. 相似文献
86.
Jian-Xin Zhao Lian Yang Zhen-Nan Gu Hai-Qin Chen Feng-Wei Tian Yong-Quan Chen Hao Zhang Wei Chen 《International journal of molecular sciences》2011,12(1):1-11
The interdomain instability of single-chain fragment variable (scFv) might result in intermolecular aggregation and loss of function. In the present study, we stabilized H4—an anti-aflatoxin B1 (AFB1) scFv—with an interdomain disulfide bond and studied the effect of the disulfide bond on antibody affinity. With homology modeling and molecular docking, we designed a scFv containing an interdomain disulfide bond between the residues H44 and L100. The stability of scFv (H4) increased from a GdnHCl50 of 2.4 M to 4.2 M after addition of the H44-L100 disulfide bond. Size exclusion chromatography revealed that the scFv (H44-L100) mutant existed primarily as a monomer, and no aggregates were detected. An affinity assay indicated that scFv (H4) and the scFv (H44-L100) mutant had similar IC50 values and affinity to AFB1. Our results indicate that interdomain disulfide bonds could stabilize scFv without affecting affinity. 相似文献
87.
目的:探讨根据CYP2C19代谢分型进行的个体化用药调整对于氯吡格雷治疗缺血性脑卒中的指导作用,为临床个体化用药提供参考。方法:纳入80例脑梗死患者,根据是否行CYP2C19基因检测分为经基因检测的个体化用药指导组40例和非基因检测的对照组40例。个体化用药指导组根据CYP2C19代谢分为:慢代谢型、中间代谢型、快代谢型及超快代谢型。快代谢型及超快代谢型按照常规使用氯吡格雷75 mg,每天1次。中间代谢型采用双倍氯吡格雷剂量150 mg,每天1次。慢代谢型患者氯吡格雷更换为替格瑞洛90 mg,每天2次或停用氯吡格雷,改用阿司匹林肠溶片100 mg每天1次;对照组按照常规使用氯吡格雷75 mg,每天1次。对所有入组患者出院后进行为期3个月的门诊或电话随访。比较两组血管事件发生率和改良Rankin量表(mRS)(0-1)发生率。结果:个体化用药指导组血管事件发生率明显低于对照组,mRS评分(0-1)发生率明显高于对照组,差异均有统计学意义(P<0.05)。结论:经CYP2C19基因检测对缺血性脑卒中患者进行的个体化用药,能显著降低血管不良事件发生率,同时对于患者预后生活能力改善也有显著提高。 相似文献
88.
《Food Control》2015
Tree nut allergies are considered an important health issue in developed countries. To comply with the regulations on food labeling, reliable allergen detection methods are required. In this work we isolated almond-specific recombinant antibody fragments (scFv) from a commercial phage display library bypassing the use of live animals, hence being consistent with the latest policies on animal welfare. To this end an iterative selection procedure employing the Tomlinson I phage display library and a crude almond protein extract was carried out. Two different almond-specific scFv (named PD1F6 and PD2C9) were isolated after two rounds of biopanning, and an indirect phage ELISA was implemented to detect the presence of almond protein in foodstuffs. The isolated scFvs demonstrated to be highly specific and allowed detection of 40 ng mL−1 and 100 ng mL−1 of raw and roasted almond protein, respectively. The practical detection limit of the assay in almond spiked food products was 0.1 mg g−1 (110–120 ppm). The developed indirect phage ELISA was validated by analysis of 92 commercial food products, showing good correlation with the results obtained by a previously developed real-time PCR method for the detection of almond in foodstuffs. The selected phage clones can be affinity maturated to improve their sensitivity and genetically engineered to be employed in different assay formats. 相似文献
89.
Nan Zhang Jie Zhong Song Han Yun Li Yanling Yin Junfa Li 《International journal of molecular sciences》2016,17(9)
miRNAs have been linked to many human diseases, including ischemic stroke, and are being pursued as clinical diagnostics and therapeutic targets. Among the aberrantly expressed miRNAs in our previous report using large-scale microarray screening, the downregulation of miR-378 in the peri-infarct region of middle cerebral artery occluded (MCAO) mice can be reversed by hypoxic preconditioning (HPC). In this study, the role of miR-378 in the ischemic injury was further explored. We found that miR-378 levels significantly decreased in N2A cells following oxygen-glucose deprivation (OGD) treatment. Overexpression of miR-378 significantly enhanced cell viability, decreased TUNEL-positive cells and the immunoreactivity of cleaved-caspase-3. Conversely, downregulation of miR-378 aggravated OGD-induced apoptosis and ischemic injury. By using bioinformatic algorithms, we discovered that miR-378 may directly bind to the predicted 3′-untranslated region (UTR) of Caspase-3 gene. The protein level of caspase-3 increased significantly upon OGD treatment, and can be downregulated by pri-miR-378 transfection. The luciferase reporter assay confirmed the binding of miR-378 to the 3′-UTR of Caspase-3 mRNA and repressed its translation. In addition, miR-378 agomir decreased cleaved-caspase-3 ratio, reduced infarct volume and neural cell death induced by MCAO. Furthermore, caspase-3 knockdown could reverse anti-miR-378 mediated neuronal injury. Taken together, our data demonstrated that miR-378 attenuated ischemic injury by negatively regulating the apoptosis executioner, caspase-3, providing a potential therapeutic target for ischemic stroke. 相似文献
90.
Jason J. Chang Ansley Stanfill Tayebeh Pourmotabbed 《International journal of molecular sciences》2016,17(8)
Stroke remains the fifth leading cause of mortality in the United States with an annual rate of over 128,000 deaths per year. Differences in incidence, pathogenesis, and clinical outcome have long been noted when comparing ischemic stroke among different ethnicities. The observation that racial disparities exist in clinical outcomes after stroke has resulted in genetic studies focusing on specific polymorphisms. Some studies have focused on matrix metalloproteinases (MMPs). MMPs are a ubiquitous group of proteins with extensive roles that include extracellular matrix remodeling and blood-brain barrier disruption. MMPs play an important role in ischemic stroke pathophysiology and clinical outcome. This review will evaluate the evidence for associations between polymorphisms in MMP-1, 2, 3, 9, and 12 with ischemic stroke incidence, pathophysiology, and clinical outcome. The role of polymorphisms in MMP genes may influence the presentation of ischemic stroke and be influenced by racial and ethnic background. However, contradictory evidence for the role of MMP polymorphisms does exist in the literature, and further studies will be necessary to consolidate our understanding of these multi-faceted proteins. 相似文献