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71.
核仁磷酸蛋白(NPM/B23)是一类穿梭于核仁、核质和胞质的多功能蛋白质。核仁磷酸蛋白参与核糖体的生物合成,控制中心体复制,并可通过多种信号通路调节细胞增殖和凋亡,参与肿瘤的发生。近年来对NPM/B23的研究多集中于NPM/B23基因突变与血液肿瘤的关系,另有许多研究表明NPM/B23在一些实体肿瘤中过表达,并与肿瘤的发生、发展密切相关。核仁磷酸蛋白可能是许多实体肿瘤的肿瘤标志物之一,但其在子宫内膜癌中作用的报道较少。因此,该文就核仁磷酸蛋白及其与子宫内膜癌关系的研究现状进行综述。 相似文献
72.
73.
Goal‐directed behaviors in patients with schizophrenia: Concept relevance and updated model
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Goal‐directed behaviors are formulated to pursue a given objective by constructing a plan and selecting actions that lead to the intended goal, either immediately or over an extended period. This concept is important to the study of human behavior because of its involvement in the majority of complex or novel situations that an individual may encounter, regardless of the cognitive, affective, or social abilities required. In this paper, we aim to demonstrate the relevance of goal‐directed behaviors to our understanding of the cognitive deficits and other symptoms associated with schizophrenia. A systematic analysis of this relation may allow us to develop integrative hypotheses regarding positive, negative, and disorganized symptoms of schizophrenia rather than consider them to be distinct issues. In this article, we review previous studies of goal‐directed actions in patients with schizophrenia in order to clarify the relevant concepts and provide a theoretical basis for the integration of existing results. Based on available theoretical models and data, we propose an updated model to facilitate further investigation of schizophrenia‐related impairments in goal‐directed behaviors. 相似文献
74.
尿动力学在前列腺增生诊疗中的策略及其理论支撑 总被引:1,自引:0,他引:1
BPH患者的梗阻性和刺激性下尿路症状多种多样,缺乏特异性。尿动力学检鹰对BPH患者确定膀胱出口梗阻部位及程度、评估逼尿肌功能状态、预测手术疗效和并发症、术后评价疗效及分析并发症的原因均有重要的应用价值,对于合理选择BPH治疗策略的参考作用不可替代。 相似文献
75.
Ajay J Kirtane Jonathan J Vafai Sabina A Murphy Julian M Aroesty Marc S Sabatine Christopher P Cannon C Michael Gibson 《European heart journal》2006,27(17):2040-2045
AIMS: The presence of residual thrombus following fibrinolytic therapy for ST-segment elevation myocardial infarction (STEMI) may predispose to greater embolization and microvascular dysfunction. METHODS AND RESULTS: We hypothesized that even in the presence of a patent epicardial artery, residual thrombus would be associated with worsened TIMI myocardial perfusion grades (TMPG), independent of epicardial flow. Data were analysed from the angiograms of 2684 patients enrolled in the CLARITY-TIMI 28 trial, with angiographically patent arteries (TIMI 2/3 flow) at a median of 88 h following fibrinolytic therapy. Thrombus in a patent epicardial artery was observed more frequently among patients with shorter times from randomization to angiography, among patients with non-left anterior descending infarctions, and among patients treated with placebo (vs. clopidogrel). Thrombus was associated with more frequent TIMI 2 flow (35.1 vs. 22.1%, P < 0.001), higher corrected TIMI frame counts (CTFC) (42 vs. 33 frames, P < 0.001), and a lower incidence of normal TMPG 3 (48.7 vs. 63.9%, P < 0.001), irrespective of treatment with clopidogrel or placebo. In multivariable analyses, thrombus remained associated with higher CTFC (P < 0.001) and worse TMPG (OR 1.6 for TMPG 0/1/2, P < 0.001) after adjustment for baseline covariates as well as known correlates of TMPG. The association between thrombus and impaired TMPG remained even after further adjustment for CTFC or TIMI flow grade. CONCLUSION: Residual angiographic thrombus following fibrinolytic therapy in STEMI patients is associated with impaired myocardial perfusion, independent of epicardial flow. This finding emphasizes the roles of platelet aggregation and distal embolization in the pathogenesis of microvascular dysfunction in STEMI. 相似文献
76.
目的:探讨冠状动脉慢血流(coronary slow flow, CSF)现象的临床危险因素及炎症反应在其发病机制中的可能作用。方法:采用校正的心肌梗死溶栓治疗(thrombolysis in myocardial infarction, TIMI)临床试验血流帧数(corrected TIMI frame count, CTFC)评价冠状动脉血流情况。入选我院2016年1月至2016年12月择期行冠状动脉造影(coronary angiography, CAG)并证实CSF的患者96例为CSF组,入选同期行CAG证实血流完全正常的患者106例为非慢血流(non-CSF, NCSF)组。比较两组患者的临床特点、生化指标及相关炎症因子(包括外周静脉血及冠状动脉血)之间的差异,炎症因子包括:白细胞介素-6(interleukin-6, IL-6)、超敏C反应蛋白(hypersensitive C reactive protein, hsCRP)、基质金属蛋白酶-9(matrix metalloproteinase-9, MMP-9)。同时进行单因素及多因素Logistic回归分析,分析CSF的危险因素及其与炎症反应的相关性。结果:CSF组冠状动脉三分支的CTFC值均显著高于NCSF组(前降支:32.3±3.7 vs 17.8±2.1;回旋支:34.5±3.9 vs 23.1±2.8;右冠状动脉:34.9±4.3 vs 21.4±3.2,P均<0.01),且右冠状动脉为CSF最常见的受累冠脉(83.3%)。单因素分析发现:CSF组患者体质指数,糖尿病比例,尿酸,冠状动脉血IL-6、hsCRP,外周静脉血及冠状动脉血MMP-9均显著高于NCSF组(P<0.05或0.01)。Logistic回归分析发现:体质指数(OR=1.313, 95%CI 1.026~1.654, P=0.034)、糖尿病(OR=1.604, 95%CI 1.198~2.466, P=0.006)、高尿酸水平(OR=1.036, 95%CI 1.006~1.102, P=0.027)、外周静脉血MMP-9(OR=2.279, 95%CI 1.478~4.022, P=0.004)、受累冠状动脉血MMP-9(OR=3.145, 95%CI 2.011~5.023, P=0.000)是发生CSF的独立危险因素。结论:体质指数、糖尿病、尿酸是CSF发生的独立危险因素;与全身炎症反应相比,受累冠脉局部炎症反应与CSF更相关;炎症因子MMP-9在CSF的病理生理过程中发挥重要作用。 相似文献
77.
目的:运用Mobley模型分析护理人员流失的影响因素,为护理管理者有针对性地采取措施提供依据。方法采用问卷调查法对2011—2013年某三级甲等综合医院流失的护理人员基本情况和离职原因进行调查,并运用Mobley模型分析离职影响因素。结果影响因素中,非工作价值观及偶然因素所占比例最大(56.39%),其次为工作满意度(21.81%)和组织内、外工作角色及收益预期(21.80%)。结论建立良好的工作环境,实行专业化的岗位管理,倡导“磁性”的管理理念,是提高护士工作满意度,稳定护理队伍的关键。 相似文献
78.
B Lind J Nowak J Dorph J van der Linden L A Brodin 《European journal of echocardiography》2002,3(3):214-219
AIMS: Movements of myocardial walls include components of high velocity and short duration calling for a high sampling rate in the acquisition of tissue velocity imaging data. This study aims at establishing the optimal sampling requirements for tissue velocity imaging measurements. METHODS AND RESULTS: In 16 healthy individuals, tissue velocity imaging data were acquired at a frame rate of 141-203 frames/s for a subsequent off-line analysis using software enabling a reduction of the sampling rate to 50%, 25% and 12.5% of the initial frame rate. Different components of the myocardial velocity profile were measured at each of these frame rates. The deviation of the results from the initial values increased markedly at decreasing frame rates, producing an underestimation of peak systolic and diastolic velocities, most other measured parameters being overestimated. A cut-off point for an acceptable < or =10% deviation of the results corresponded to at least 70 frames/s for peak systolic and early diastolic velocity, and to at least 100 frames/s for other systolic and diastolic parameters. CONCLUSION: A high sampling rate is essential for a proper rendering of tissue velocity imaging signals, too low frame rates resulting in inferior accuracy of the results. This should be kept in mind while viewing reported tissue velocity imaging data. 相似文献
79.
《Autoimmunity》2013,46(4):294-303
The supplanting of the 1° IgM response by the 2° isotype-switched response is one of the best known phenomena of immune system dynamics. Given that the conditions determining which B cells will switch isotype and which ones will not are intrinsic to the entities of the immune system, it should be possible to predict the effects that the small-scale (e.g. molecular) properties have on the large scale dynamics of isotype switch. However, in practice, it is notoriously difficult to predict large scale, emergent effects from small scale conditions. Thus, it is unclear what effects (if any), mutation, IgM avidity and chronic immunization exert on isotype switch. To explore these effects, we have constructed a model of isotype switch. With this model, a modified version of the IMMSIM cellular automaton, we are able to alter small scale parameters at will and thus determine the conditions that lead to the observed large scale dynamics of isotype switch. We show that isotype switch is stabilized by high-IgM avidity, affinity/isotype-dependent cell division, and, surprisingly, mutation. We also demonstrate that chronic immunization leads, in our model, to a severe depletion of the IgM response even while the IgG response remains normal. 相似文献
80.
《Journal of medical engineering & technology》2013,37(5-6):306-315
This paper presents a general embedded processing system implemented in a field-programmable gate array providing high frame rate and high accuracy for a laser Doppler blood flow imaging system. The proposed system can achieve a basic frame rate of flow images at 1 frame/second for 256×256 images with 1024 fast Fourier transform (FFT) points used in the processing algorithm. Mixed fixed-floating point calculations are utilized to achieve high accuracy but with a reasonable resource usage. The implementation has a root mean square deviation of the relative difference in flow values below 0.1% when compared with a double-precision floating point implementation. The system can contain from one or more processing units to obtain the required frame rate and accuracy. The performance of the system is significantly higher than other methods reported to date. Furthermore, a dedicated field-programmable gate array (FPGA) board has been designed to test the proposed processing system. The board is linked with a laser line scanning system, which uses a 64×1 photodetector array. Test results with various operating parameters show that the performance of the new system is better, in terms of noise and imaging speed, than has been previously achieved. 相似文献