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81.
目的: 探讨在高转移人乳腺癌细胞中,核因子κB活性对肿瘤生长及运动迁移能力的影响。方法: 转染显性负性突变的ⅠκBα重组质粒入高转移乳腺癌细胞MDA-MB-231、MDA-MB-435,筛选并鉴定稳定转染的细胞株;凝胶迁移实验观察核因子κB活性,细胞生长曲线、平板集落形成试验及Millicell-PCF培养小室观察质粒转染对细胞生长和趋化运动的影响。结果: 乳腺癌MDA-MB-231、MDA-MB-435细胞中存在高NF-κB组成型激活,稳定转染显性负性的ⅠκBα质粒后,细胞NF-κB活性下调,在不明显影响细胞生长、克隆形成的情况下,抑制高转移乳腺癌细胞株的运动能力。结论: 在体外,抑制NF-κB通路,可明显抑制高转移乳腺癌细胞株的运动迁移能力。  相似文献   
82.
489例不良孕产史患者细胞遗传学分析   总被引:1,自引:3,他引:1  
目的探讨染色体异常对生育的影响.方法对489例有自然流产、胎停育或生育畸形儿史的患者进行外周血淋巴细胞培养,G显带染色体核型分析.结果 489例患者中染色体核型异常24例, 异常率达4.9%, 其中有自然流产、胎停育史的患者核型异常占20例,有生育畸形儿史的患者核型异常占4例.染色体变异共21例,占4.3%.结论染色体异常是导致不良生育的重要影响因素, 应重视遗传学检查,进行优生优育指导.  相似文献   
83.
Control of the neck muscles is coordinated with the sensory organs of vision, hearing and balance. For instance, activity of splenius capitis (SC) is modified with gaze shift. This interaction between eye movement and neck muscle activity is likely to influence the control of neck movement. The aim of this study was to investigate the effect of eye position on neck muscle activity during cervical rotation. In eleven subjects we recorded electromyographic activity (EMG) of muscles that rotate the neck to the right [right obliquus capitis inferior (OI), multifides (MF), and SC, and left sternocleidomastoid (SCM)] with intramuscular or surface electrodes. In sitting, subjects rotated the neck in each direction to specific points in range that were held statically with gaze either fixed to a guide (at three different positions) that moved with the head to maintain a constant intra-orbit eye position or to a panel in front of the subject. Although right SC and left SCM EMG increased with rotation to the right, contrary to anatomical texts, OI EMG increased with both directions and MF EMG did not change from the activity recorded at rest. During neck rotation SCM and MF EMG was less when the eyes were maintained with a constant intra-orbit position that was opposite to the direction of rotation compared to trials in which the eyes were maintained in the same direction as the head movement. The inter-relationship between eye position and neck muscle activity may affect the control of neck posture and movement.  相似文献   
84.
A wireless recording system was developed to study the electroencephalogram (EEG) in unrestrained, male Landrace piglets. Under general anesthesia, ball-tipped silver/silver chloride electrodes for EEG recording were implanted onto the dura matter of the parietal and frontal cortex of the piglets. A pair of miniature preamplifiers and transmitters was then mounted on the surface of the skull. To examine whether other bioelectrical activities interfere with the EEG measurements, an electrocardiogram (ECG) or electromyogram (EMG) of the neck was simultaneously recorded with the EEG. Next, wire electrodes for recording movement of the eyelid were implanted with EEG electrodes, and EEG and eyelid movements were simultaneously measured. Power spectral analysis using a Fast Fourier Transformation (FFT) algorithm indicates that EEG was successfully recorded in unrestrained piglets, at rest, during the daytime in the absence of interference from ECG, EMG or eyelid movements. These data indicate the feasibility of using our radiotelemetry system for measurement of EEG under these conditions.  相似文献   
85.
Eugene  Aserinsky 《Psychophysiology》1986,23(3):340-347
The third derivative of motion or the change in the rate of acceleration (also known as jerk) is examined in terms of its applicability to the study of psychophysiological function. An algorithm of this third derivative is presented to show that jerk can be derived from the arithmetic difference of two slopes which constitute the portion of motion being differentiated. By modifying the algorithm, a new parameter termed “proportional jerk’ or PJ is formulated whereby one slope is measured relative to the other slope; this PJ provides information about the smoothness of movement without being influenced by the velocity as is the traditional jerk measure. A practical application of the PJ to waking saccades and REMs in 11 human subjects revealed that REMs are significantly “jerkier’ or less smooth than waking calibration eye movements. Whereas the waking eye movements had a well-defined negative phase of the PJ, the REMs did not show such stereotypical behavior. This is in accord with previous work which showed that waking saccade velocity increases to a maximum and then decreases whereas REMs maintain their peak or near peak velocities for varying periods. It was suggested that PJ can be useful in detecting subtle temporal changes in the course of movements and may be used as a parameter of motion even when the absolute amplitude is unknown.  相似文献   
86.
The effects of environmental constraints upon licking patterns   总被引:1,自引:0,他引:1  
Rats licked water under three degrees of environmental constraint. As restriction decreased, lick duration increased. Interlick interval changed independently of duration. Lickometer-measured drinking tube contact was longer than fluid contact unless access was highly restricted. The use of controlled access to measure minimal necessary taste input is discussed.  相似文献   
87.
Face perception plays a crucial role in primate social communication. We have investigated the pattern of eye movements produced by rhesus monkeys (Macaca mulatta) as they viewed images of faces. Eye positions were recorded accurately using implanted eye coils, while neutral upright, inverted and scrambled images of monkey and human faces were presented on a computer screen. The monkeys exhibited a similar eye scan pattern while viewing familiar and unfamiliar monkey face images, or while viewing monkey and human face images. No differences were observed in the distribution of viewing times, number of fixations, time into the trial of first saccade to local facial features, and the temporal and spatial characteristics of viewing patterns across the facial images. However, there was a greater probability of re-fixation of the eye region of unfamiliar faces during the first few seconds of the trial suggesting that the eyes are important for the initial encoding of identity. Indeed, the highest fixation density was found in the eye region of all the face images. The viewing duration and the number of fixations per image decreased when inverted or scrambled faces were presented. The eye region in these modified images remained the primary area of fixation. However, the number of fixations directed to the eyes decreased monotonically from the upright images through the inverted versions to the scrambled face images. Nonetheless, the eyes remain the most salient facial substructure regardless of the arrangement of other features, although the extent of salience which they attain may depend both on the low level properties of the eyes and on the global arrangement of facial features. Electronic Publication  相似文献   
88.
目的探讨不孕不育及自发流产与染色体核型异常的关系,指导临床对这些疾病的诊断。方法采集922例生殖异常患者外周静脉血,进行淋巴细胞培养,常规方法收获细胞,低渗、固定、制片、经G显带处理、镜检,进行观察研究。结果922例患者共检出异常核型66例,总检出率7.16%。其中,易位21例,倒位21例,克氏综合征18例,X-三体综合征2例,Turner综合征伴X染色体缺失1例,Y染色体缺失1例,环状21号染色体1例,额外标记染色体1例,及常见染色体多态性大Y染色体63例,发生率13.35%。结论染色体异常是导致不孕不育及自发流产的重要原因之一,对生殖异常患者进行染色体检查可为临床诊断和优生优育提供依据。  相似文献   
89.
Male Sprague-Dawley rats with combined lesions to the dorsal and lateral aspects of the entorhinal cortex in one hemisphere and of the contralateral dorsolateral hippocampal formation were compared with both operated and unoperated controls on three different behaviors, monitored across a 53 day postoperative period. The rats with the combined entorhinal cortex-hippocampal lesions (EH) showed transient hyperactivity in the open field, transient reduction in spontaneous alternation levels in an unbaited T-maze and persistent deficits in learning spatial maze problems. The results of the present experiment are discussed in comparison with those from experiments on rats with bilateral hippocampal lesions and those from experiments on rats with bilateral entorhinal cortex lesions. Although some similarities among these findings suggest that these two brain regions probably function in a coordinated fashion with respect to these behaviors, differences in the various syndromes are also discussed.  相似文献   
90.
204对自然流产夫妇染色体核型分析   总被引:1,自引:1,他引:1  
目的 分析自然流产与染色体异常核型之间的关系.方法 采用人外周血淋巴细胞培养,常规G显带技术行染色体核型检查,后结合临床资料对其进行分析.结果 204对自然流产夫妇中,检出染色体异常16例(平衡易位15例,罗伯逊易位1例),检出率3.82%,较一般人群的染色体异常率为高,差异有显著性(P<0.01);检出染色体多态性39例,检出率9.56%;流产例次染色体异常组(2.94±0.85)及多态性组(2.76±1.45)均较正常染色体组(1.05±1.39)为高,差异皆有显著性(P<0.01).结论 人体夫妇染色体异常是流产的重要原因之一,但染色体多态性方面的因素也不可忽视.对自然流产夫妇进行常规的染色体检查及遗传咨询具有一定的临床意义.  相似文献   
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