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61.
目的:探讨老年慢性房颤患者血清热休克蛋白70(HSP70)及胱抑素C(CysC)表达水平及两者在房颤发生中的意义. 方法:选择2014年1月至2015年1月诊治的老年慢性房颤患者100例为房颤组,其中阵发性房颤28例,持续性房颤31例,永久性房颤41例. 另选取年龄、性别匹配的非房颤老年患者55例为对照组,检测两组血清HSP 70及CysC浓度. 结果:与对照组比较,房颤组患者血清HSP70及CysC水平明显升高(P<0.05),且在阵发性、持续性和永久性三种房颤亚型中,HSP70和Cysc浓度依次递增. Logistic回归分析显示HSP70(OR=0.629,P=0.023)和CysC(OR=1.206,P=0. 015)是房颤发生的独立预测因子,且两者呈正相关( r=-0.257,P<0.05). 结论:炎症因子HSP70 和CysC水平升高与房颤的发生发展密切相关.  相似文献   
62.
目的观察脑梗死大鼠经血管内皮生长因子(VEGF)165基因治疗后热休克蛋白70(HSP70)的表达。方法将25只大鼠随机均分为以下5组:正常对照组(A组);假大脑中动脉闭塞(MCAO)组(B组);MCAO组;空载质粒对照组(D组);hVEGF165基因治疗组(E组)。建模7 d后采用免疫组化的方法观察各组动物脑组织中的HSP70 的表达。结果(1)在皮质中,A、B两组HSP70均低表达(P>0.05);C、D两组表达均较高(P>0.05),与A、B两组相比有较显著的差异(P<0.01);E组表达最强,与各组相比均有显著差异(P<0.01)。(2)在半暗带中,C、D、E各组HSP70 表达均较高,C、D两组间无显著差异(P>0.05),而E组显著高于C、D组(P<0.01)。(3)在梗死灶内,E 组表达较高,显著高于C、D组(P< 0.01)。结论经hVEGF165基因治疗的脑梗死大鼠HSP70表达显著增高,提示VEGF165基因可诱导HSP70的表达。  相似文献   
63.
目的 检测人卵巢癌HO-8910细胞膜上热休克蛋白70(HSP70)的表达。方法 HO-8910细胞株体外传代培养,应用流式细胞仪、间接免疫荧光法检测细胞膜上HSP70的表达。结果 HO-8910细胞膜上HSP70表达率为6%,平均荧光强度为9.05。结论 HSP70的低表达可能与肿瘤的发生发展有关,为更好地了解HSP70在肿瘤细胞表面的调节活动及对肿瘤细胞内外信号反应的生物学行为奠定了基础,对进一步研究肿瘤的防治有一定的实际意义。  相似文献   
64.
Intracellular heat shock proteins (HSP) function as molecular chaperones, they support folding and transport mechanisms of other proteins under physiological conditions and following physical or chemical stress. More recently, extracellular localized HSP have been found to play key roles in the induction of a cellular immune response. Either they act as carrier molecules for immunogenic peptides that are presented on Antigen Presenting Cells (APC) to cytotoxic T-cells or they themselves act as activatory molecules for the innate immune system. Binding of uncomplexed HSP to HSP-receptors on APC has been found to induce the secretion of inflammatory cytokines. Furthermore, an unusual tumor-selective membrane-localization of non-conserved regions of the 72000Da HSP (Hsp70) has been found to act as a recognition structure for natural killer (NK) cells. In this review the interaction of NK cells with Hsp70 or peptides derived thereof will be eluciated in more detail.  相似文献   
65.

Statement of problem

Polymeric material for 3-dimensional printing can be used to fabricate occlusal devices. However, information about fracture resistance and wear is scarce.

Purpose

The purpose of this in vitro study was to investigate the fracture resistance and 2-body wear of 3-dimensional–printed (3DP) (FotoDent splint; Dreve Dentamid GmbH), milled polymethylmethacrylate (CAM) (Temp Basic; Transpa 95H16, Zirkonzahn GmbH), and conventionally fabricated polymethylmethacrylate (CAST) (Castdon; Dreve Dentamid GmbH) occlusal devices.

Material and Methods

A total of 96 occlusal devices were prepared according to the 3 different manufacturing techniques 3DP, CAM, and CAST (n=32). For each manufacturing technique, specimens were further divided into initial fracture resistance tests (n=16) and artificial aging in the mastication simulator (50 N, 37°C) with 2-body wear followed by fracture resistance tests (n=16). The fracture resistance was determined using a universal testing machine (1 mm/min). The wear was measured after 20?000 and 120?000 mastication cycles with the replica technique, mapped with a laser scanner, and quantified in R software. Data were analyzed using a 2-way ANOVA followed by a 1-way ANOVA with Scheffé or Games-Howell post hoc tests, repeated measures ANOVA with corrected Greenhouse-Geisser P values, and the Levene, Mann-Whitney, and paired t tests (α=.05).

Results

CAM presented higher initial fracture resistance than 3DP or CAST (P<.001). After mastication simulation, CAM followed by 3DP showed higher fracture resistance than CAST (P<.001). Mastication simulation decreased the fracture resistance for CAM and CAST (P<.001) but not for 3DP (P=.78). Three-dimensional–printed occlusal devices showed the highest material volume loss, followed by CAM and the lowest in CAST (P<.001).

Conclusions

Three-dimensional–printed occlusal devices showed lower wear resistance and lower fracture resistance than those milled or conventionally fabricated. Therefore, only short-term application in the mouth is recommended. Further developments of occlusal device material for 3-dimensional printing are necessary.  相似文献   
66.
Arimoclomol, an amplifier of heat shock protein expression involved in cellular stress response, has emerged as a potential therapeutic candidate in amyotrophic lateral sclerosis (ALS) in recent years. Treatment with arimoclomol was reported to improve survival and muscle function in a mouse model of motor neuron disease. Several single- and multiple-dose safety studies have been completed in healthy control subjects. A 3-month Phase IIa study in people with ALS demonstrated safety at dosages up to 300 mg/day and another study is currently recruiting participants with familial ALS caused by mutations in the superoxide dismutase gene. We review the rationale for testing arimoclomol in sporadic and familial ALS in the context of available safety and pharmacokinetic data. Published and unpublished literature relative to the drug in the past two decades is discussed. The current review attempts to bring together our existing understanding of the actions of arimoclomol with the disease profile of ALS. The pharmacological profile of arimoclomol and the available preclinical data make it a promising therapeutic possibility in ALS.  相似文献   
67.
68.
ObjectivesThe study aimed to analyse the association between Sports-Related Concussion (SRC) and Subsequent Musculoskeletal Injury (MSK) in United Kingdom university-aged rugby union players whilst considering the effects of sex, athlete playing position and injury location.DesignRetrospective cohort study. A period of 365 days with 0–90, 91–180 and 181–365 days sub-periods was analysed for the following variables; MSK injury incidence, occurrence, severity, injury location, playing position and sex.SettingInjury data was collected from the Sports Development Centre database at Loughborough University.ParticipantsA total of 408 injuries in 181 athletes (55 females and 126 males) were included.ResultsThe MSK injury incidence of SRC group was significantly higher than control and higher post-SRC than pre-SRC period over a 365-day period (p=0.012 and p=0.034, respectively). The odds ratios of MSK injury incidence between groups and between periods were 1.62 (95% CI, 1.10–2.25) and 1.57 (95% CI ,1.08–2.29). A SRC was not associated with a greater time loss from a subsequent MSK injury or a specific MSK injury location.ConclusionsAthletes with a second recorded injury were more likely to sustain a MSK injury if they had experienced SRC, however, there was no indication a SRC resulted in greater time loss from a MSK injury.  相似文献   
69.
Bovine paratuberculosis is a highly prevalent chronic infection of the small intestine in cattle, caused by Mycobacterium avium subspecies paratuberculosis (MAP). In earlier studies we showed the protective effect of Hsp70/DDA subunit vaccination against paratuberculosis. In the current study we set out to measure primary immune responses generated at the site of Hsp70 vaccination. Lymph vessel cannulation was performed to obtain efferent lymph from the prescapular lymph node draining the neck area where the vaccine was applied. Hsp70 vaccination induced a significant increase of CD21+ B cells in efferent lymph, accounting for up to 40% of efferent cells post-vaccination. Proliferation (Ki67+) within the CD21+ B cell and CD4+ T cell populations peaked between day 3 and day 5 post-vaccination. From day 7, Hsp70-specific antibody secreting cells (ASCs) could be detected in efferent lymph. Hsp70-specific antibodies, mainly of the IgG1 isotype, were also detected from this time point onwards. However, post-vaccination IFN-γ production in efferent lymph was non-sustained. In conclusion, Hsp70-vaccination induces only limited Th1 type immune responsiveness as reflected in efferent lymph draining the vaccination site. This is in line with our previous observations in peripheral blood. The main primary immunological outcome of the Hsp70/DDA subunit vaccination is B cell activation and abundant Hsp70-specific IgG1 production. This warrants the question whether Hsp70-specific antibodies contribute to the observed protective effect of Hsp70 vaccination in calves.  相似文献   
70.
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