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51.
胃黏膜上皮内瘤变是胃癌前病变,具有发展为胃癌的危险。阳主动,阴主静,文章基于阴阳理论,衷中参西,微观辨证与宏观辨证结合,以阴阳消长失调和基因调控紊乱的关系为出发点,认为胃黏膜上皮内瘤变发生时胃黏膜细胞凋亡周期紊乱和细胞异常增殖分化是阴阳消长失衡在细胞基因调控水平上的体现,进而探讨胃黏膜上皮内瘤变的病因病机以及辨证论治过程,为中医药治疗胃黏膜上皮内瘤变提供更多的理论依据,丰富治疗该病的临床手段。  相似文献   
52.
本文就心阻抗容积图的传统理论及其局限性展开讨论。由于传统理论模型与人体胸部结构差异太大,使这一方法存在很多问题。而实践中关于心输出量(CO)的计算,误差较大,可靠性差。  相似文献   
53.
Mathematical and computational models are designed to improve our understanding of biological phenomena, to confirm/reject hypotheses, and to find points of intervention by altering the behavior of the studied systems. Here we describe the role of mathematical/computational models of the immune system. In particular, we analyze some examples of how mathematical modeling can contribute to finding optimal vaccination strategies. Indeed, computational modeling offers an intriguing opportunity from the theoretical point of view, and it will be of interest for clinically oriented investigators who wish to find optimal therapeutic strategies and for pharmaceutical industries that want to produce effective and successful drugs.  相似文献   
54.
Robert D.  Hare  Daniel  Craigen 《Psychophysiology》1974,11(2):197-206
Heart rate (HR) and skin conductance (SC) were recorded while 17 psychopathic (P) and 17 nonpsychopathic (NP) inmates (referred to as A) were engaged in a mixed-motive game situation with another S (referred to as B). On each trial A had to choose the intensity of shock to be delivered to himself and to B. B then was given a chance to retaliate, although his choices were actually overridden by the experimenter. A 10 sec tone (CS) preceded delivery of shock to each S. There were no differences between Groups P and NP in the intensity of shock chosen for themselves and for the other (B) Ss. Compared with Group NP, Group P gave small unconditioned skin conductance (SC) responses to shock directly received and to shocks delivered to the other S. There were no differences between groups in the unconditioned HR response to either direct shock (acceleration) or to shocks delivered to the other S (slight deceleration). Group P gave small electrodermal orienting responses (ORs) and anticipatory responses (ARs) to the CS preceding shock to self and shock to other; Group NP gave relatively large ORs and ARs to the CS preceding shock to self, and small ones prior to shock to other. Both Groups gave a biphasic conditioned HR response–acceleration followed by deceleration; each component was larger in Group P than in Group NP, and the acceleratory component in Group P appeared on the first trial. The electrodermal data were consistent with the view that psychopaths experience little fear arousal prior to reception of aversive stimuli by themselves or by others. It was suggested that the anticipatory HR responses of the psychopathic Ss were part of an adaptive response that helped them to cope with stress.  相似文献   
55.
Summary The purpose of this study was to compare two ways of estimating both fatigue and fitness indicators from systems model of the effects of training on performance. The model was applied to data concerning the training of a hammer thrower. The variations in performance were mathematically related to the successive amounts of training. The model equation was composed of negative (NF) and positive (PF) functions. The NF and PF were associated with the fatigue and fitness estimated in previous studies. Using another method, fatigue and fitness indicators were estimated from a combination of NF and PF. The influence of training on performance was negatively associated with fatigue (NI), and positively to fitness (PI). The changes in performance were well described by the model in the present study (r = 0.96,N = 19,P<0.001). Significant correlations were observed between NF and NI (r = 0.93,P < 0.001) on the one hand and between PF and PI (r = 0.90,P < 0.001) on the other. The absolute values and the time variations of PI and NI were closer to the change in performance than NF and PF. The NF and PF were accounted for mainly by the accumulation of amounts of training. On the other hand, NI and PI were accounted for rather by the impact of these amounts of training on performance.  相似文献   
56.
An outbreak of trichinellosis in farmed wild boar in Finland   总被引:2,自引:0,他引:2  
Nine farmed wild boar out of 25 slaughtered from a single farm were condemned at meat inspection because of trichinellosis. With RAPD-PCR, Trichinella spiralis was identified in all positive wild boar. Out of the available serum samples (n=7), all wild boar which had failed the meat inspection showed seroconversion in ELISA and Western blotting, as did one additional animal which had passed the inspection. The animals became infected during an invasion of rats from an improperly closed dump near the farm. Unfortunately, by the time trichinellosis was discovered in the wild boar, the invasion had already been brought under control; thus, no samples from rats were available. However, having lived through the rat invasion was shown to be a risk factor for trichinellosis in wild boar (relative risk, RR=6.3). In wildlife samples from surrounding areas, sylvatic trichinellosis was found to be very common (74%; n= 19 red foxes). Intriguingly, the prevalent species in trichinella-positive foxes differed from that in wild boar, Trichinella nativa and T. spiralis being found in 12 foxes and in one fox, respectively.  相似文献   
57.
广泛性焦虑障碍(GAD)是普遍存在于焦虑症患者之中的基础焦虑障碍,担忧是其核心特征。在众多担忧理论之中,Wells的元认知理论是目前最有效地解释GAD的理论。由该理论发展而来的担忧量表对GAD的鉴别及诊断都显示了很好的信度和效度。  相似文献   
58.
以组分的连续性方程为基础 ,建立了药物从多孔骨架聚合物系统中释放的数学模型。在模型中引入相对渗透速度来刻画药物释放过程中不同机理的影响。对药物从多孔骨架聚合物系统中non -Fickian扩散现象进行了研究 ,特别对药物溶出机制控制的恒速释药现象进行了解释。  相似文献   
59.
A microcomputer automated system for measuring systolic time intervals is described. Electrocardiogram, phonocardiogram, and carotid pulse tracings were measured in 38 healthy male subjects during baseline conditions and during either exercise on a bicycle ergometer or a video-game task. These measurements were recorded on both a traditional 3-channel ECG recorder and the computerized system. Both methods of recording systolic time intervals were independently scored by two different experimenters. In this way, interrater reliability of hand-scoring, intermethod reliability between hand-scoring versus computer-scoring, and interrater reliability of computer-scoring could be assessed. The interrater reliabilities of hand-scored systolic time intervals were generally above .90, ranging from .73 for left ventricular ejection time to .99 for R-R intervals of the ECG, with a mean of .92. The intermethod reliability of the computer versus hand-scored systolic time intervals also proved to be generally above .90, ranging from .76 for S1-S2 components of the phonocardiogram to .99 for R-R, with a mean of .94. The interrater reliabilities of the computer-scored systolic time intervals were all above .90, ranging from .93 for S1-S2 to .99 for R-R, with a mean of .98. These data indicate that the computerized method of scoring systolic time intervals is at least as reliable as the more traditional scoring of paper tracing.  相似文献   
60.
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