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71.
In order to structure the sensory environment our brain needs to detect changes in the surrounding that might indicate events of presumed behavioral relevance. A characteristic brain response presumably related to the detection of such novel stimuli is termed mismatch negativity (MMN) observable in human scalp recordings. A candidate mechanism underlying MMN at the neuronal level is stimulus-specific adaptation (SSA) which has several characteristics in common. SSA is the specific decrease in the response to a frequent stimulus, which does not generalize to an interleaved rare stimulus in a sequence of events. SSA was so far mainly described for changes in the response to simple pure tone stimuli differing in tone frequency. In this study we provide data from the awake rat auditory cortex on adaptation in the responses to frequency-modulated tones (FM) with the deviating feature being the direction of FM modulation. Adaptation of cortical neurons to the direction of FM modulation was stronger for slow modulation than for faster modulation. In contrast to pure tone SSA which showed no stimulus preference, FM adaptation in neuronal data differed sometimes between upward and downward FM. This, however, was not the case in the local field potential data recorded simultaneously. Our findings support the role of the auditory cortex as the source for change-related activity induced by FM stimuli by showing that dynamic stimulus features such as FM modulation can evoke SSA in the rat in a way very similar to FM-induced MMN in the human auditory cortex.  相似文献   
72.
HLA‐DRB1*0401 expression in humans has been associated with a predisposition to developing rheumatoid arthritis (RA) and collagen‐induced arthritis (CIA), while HLA‐DRB1*0402 is not associated with susceptibility. Here, we determined if mice transgenic (Tg) for human *0401 have a CD4+ T‐cell repertoire that predetermines proinflammatory cytokine production. The data show that both *0401 and *0402 Tg mice can produce TH1/TH17 cytokines, although the kinetics of response may be different. However, in the context of antigen‐specific responses in a CIA model, *0402 Tg mice generate a TH2 response that may explain their resistance to developing arthritis. In addition, a significant subset of naïve CD4+ T cells from *0402 Tg mice can be activated in polarizing conditions to differentiate into Treg cells that produce IFN‐γ. *0401 Tg mice harbor memory CD4+ T cells that differentiate into IL‐17+ cells in various polarizing conditions. Our data suggest that *0401 Tg mice generate a strong immune response to lipopolysaccharide and may be efficient in clearing infection, and may *0401 have been evolutionarily selected for this ability. Autoimmunity, such as RA, could likely be a bystander effect of the cytokine storm that, along with the presence of low Treg‐cell numbers in *0401 Tg mice, causes immune dysregulation.  相似文献   
73.
Unbiased amplification of the whole‐genome amplification (WGA) of single cells is crucial to study cancer evolution and genetic heterogeneity, but is challenging due to the high complexity of the human genome. Here, we present a new workflow combining an efficient adapter‐linker PCR‐based WGA method with second‐generation sequencing. This approach allows comparison of single cells at base pair resolution. Amplification recovered up to 74% of the human genome. Copy‐number variants and loss of heterozygosity detected in single cell genomes showed concordance of up to 99% to pooled genomic DNA. Allele frequencies of mutations could be determined accurately due to an allele dropout rate of only 2%, clearly demonstrating the low bias of our PCR‐based WGA approach. Sequencing with paired‐end reads allowed genome‐wide analysis of structural variants. By direct comparison to other WGA methods, we further endorse its suitability to analyze genetic heterogeneity.  相似文献   
74.
目的 对比分析单纯后路内固定+一期经腰椎间孔病椎间病灶清除(TLIF)与经典的前后联合手术在布氏杆菌性脊柱炎患者中的临床疗效及安全性。 方法 对我院2015年1月至2017年12月收治的93例布病性脊柱炎患者的临床资料进行分析。按手术方式分为观察组(45例)和对照组(48例)。对两组患者的基础数据、临床指标、术前术后各项指标水平以及术后并发症、植骨治愈情况。 结果 观察组与对照组基础数据比较,差异无统计学意义(P>0.05)。观察组患者的手术时间、住院天数、术中出血量及术后下床时间均明显低于对照组(P<0.01)。两组患者术后3个月的ODI、VAS、CRP、ESR及Cobb角均明显低于术前(P<0.05);术后3个月,观察组患者的ODI、VAS、CRP、ESR及Cobb角均明显低于对照组(P<0.05)。观察组术后并发症发生率(4.4%)明显低于对照组(25.0%)(Χ2=7.674,P<0.01)。 结论 TLIF治疗布氏杆菌性脊柱炎患者的临床疗效突出,安全性较好,更有利于患者术后身体的恢复。  相似文献   
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76.
This study compared the biocompatibility in vitro and the osseointegration in vivo of zirconium and titanium implants regarding implant surfaces and the bone-implant contacts. The different implant surfaces and the biocompatibility of zirconium versus titanium implants were determined by vitality and cytotoxic tests in vitro. The contact of the osteoblasts to the implant surface was determined by scanning electron microscopy (SEM). The in vivo study for osseointegration was performed in domestic pigs over 4 and 12 weeks. In each animal, 4 zirconium and 4 titanium implants (WhiteSky, BlueSky, Bredent, Germany) were inserted in the os frontale and analysed by histomorphometry. Cytotoxicity and SEM showed good biocompatibility in relation to the investigated implant materials. Histological results showed direct bone-implant contact of the implant surfaces. The zirconium implants showed a slight delay in osseointegration in terms of bone-implant contact as measured by histomorphometry (after 4 weeks, zirconium (59.3 ± 4.6%) versus titanium (64.1 ± 3.9%); after 12 weeks, zirconium (67.1 ± 2.3%) versus titanium (73.6 ± 3.2%). A statistically significant difference between the two groups was not observed. The results indicated similar biocompatibility and osseointegration for zirconium compared to titanium implants.  相似文献   
77.
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79.
目的:总结以病人为中心的口腔科门诊数字化建设的经验。方法:从诊疗手段、就医流程、医疗文书以及科室管理4个方面总结广州军区武汉总医院口腔科门诊数字化建设的概况。结果:2009年以来开始进行El腔科门诊的数字化建设,经过3年多的运行,科室工作流程优化明显,提高了工作效率和医疗服务质量。结论:科室的数字化建设有助于提高科室的工作效率和医疗服务质量,充分体现了”以病人为中心”这一理念。  相似文献   
80.
Malaria remains the most important parasitic infection in humans. There have been significant advances in the treatment of both nonsevere and severe malaria with the advent of artemisinin combination therapies and parenteral artesunate, but the optimum supportive management of severe malaria is unclear. A broadly acceptable therapy for the prevention of relapses in Plasmodium vivax infection has not been discovered. Globally, the priority remains to prevent infection in the vulnerable, to move toward elimination where feasible, and to ensure that effective treatment is available to all. In developed settings, prevention of infection and its early recognition are crucial.  相似文献   
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