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31.
狂犬病病毒(RV)是一种高度嗜神经性病毒,由RV引发的狂犬病通常是一种急性致死性神经系统损伤性疾病。RV通过周围神经末梢和中枢神经系统(CNS)的神经元进行病毒的复制和传播。绝大多数狂犬病例CNS病理学表现为急性脑脊髓炎,常常没有显著的显微镜下改变,脑部可以轻度肿胀,脑膜和脑实质血管轻度充血并伴有少量炎症细胞浸润,这也是其他急性病毒性脑炎常见的共同表现。  相似文献   
32.
The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing.  相似文献   
33.
BACKGROUND: Although pedophilia is of high public concern, little is known about underlying neural mechanisms. Although pedophilic patients are sexually attracted to prepubescent children, they show no sexual interest toward adults. This study aimed to investigate the neural correlates of deficits of sexual and emotional arousal in pedophiles. METHODS: Thirteen pedophilic patients and 14 healthy control subjects were tested for differential neural activity during visual stimulation with emotional and erotic pictures with functional magnetic resonance imaging. RESULTS: Regions showing differential activations during the erotic condition comprised the hypothalamus, the periaqueductal gray, and dorsolateral prefrontal cortex, the latter correlating with a clinical measure. Alterations of emotional processing concerned the amygdala-hippocampus and dorsomedial prefrontal cortex. CONCLUSIONS: Hypothesized regions relevant for processing of erotic stimuli in healthy individuals showed reduced activations during visual erotic stimulation in pedophilic patients. This suggests an impaired recruitment of key structures that might contribute to an altered sexual interest of these patients toward adults.  相似文献   
34.
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets.  相似文献   
35.
Between 23 and 70% of occupants involved in frontal impacts sustain cervical spine injuries, many with neurological involvement. It has been hypothesized that cervical spinal cord compression and injury may explain the variable neurological profile described by frontal impact victims. The goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to quantify canal pinch diameter (CPD) narrowing during frontal impact and to evaluate the potential for cord compression. The biofidelic model and a sled apparatus were used to simulate frontal impacts at 4, 6, 8, and 10 g horizontal accelerations of the T1 vertebra. The CPD was measured in the intact specimen in the neutral posture (neutral posture CPD), under static sagittal pure moments of 1.5 Nm (pre-impact CPD), during dynamic frontal impact (dynamic impact CPD), and again under static pure moments following each impact (post-impact CPD). Frontal impact caused significant (P<0.05) dynamic CPD narrowing at C0-dens, C2-C3, and C6-C7. The narrowest dynamic CPD was observed at C0-dens during the 10 g impact and was 25.9% narrower than the corresponding neutral posture CPD. Interpretation of the present results indicate that the neurological symptomatology reported by frontal impact victims is most likely not due to cervical spinal cord compression. Cord compression due to residual spinal instability is also not likely.  相似文献   
36.
中医情志的发生机制刍议   总被引:1,自引:0,他引:1  
在情志学说和脑主神明理论指导下对情志产生的生理机制作新的诠释。认为脑神的气化出入及整合作用是情志发生的生理基础 ;五脏所化的气血精津为情志发生的物质基础  相似文献   
37.
市场机制下政府调节与医疗管制制度框架的构建   总被引:4,自引:1,他引:3  
医疗机构分类管理的政策确定了我国医疗服务的市场取向.我国医疗市场服务因其特殊的技术经济特点也存在一般意义上的市场失灵,使政府管制这一非市场治理机制的产生与存在成为必要,以弥补与矫正市场缺陷,保证医疗服务市场的规范运行和卫生改革的顺利推进.  相似文献   
38.
前列腺癌中PIM-1的表达及其临床意义   总被引:4,自引:0,他引:4  
目的 探讨PIM-1在前列腺癌中的表达及临床意义。方法 逆转录-聚合酶链反应(RT—PCR)半定量分析2例良性前列腺增生(BPH)和5例前列腺癌(PCa)组织标本中PIM-1mRNA表达,免疫组织化学法检测20例BPH、20例高分级前列腺上皮内瘤(HGPIN)和42例PCa组织标本中PIM-1蛋白表达水平,染色结果分为阴性、弱阳性、阳性和强阳性。结果 5例PCa组织PIM-1mRNA表达相对值分别为0.63、0.55、0.42、0.91、0.76,2例BPH中其相对值为0.26、0.27。BPH、HGPIN和PCa组织中PIM-1蛋白阴性表达率分别为60%(12/20)、20%(4/20)和2%(1/42),弱阳性表达率分别为40%(8/12)、20%(4/20)和12%(5/42),阳性列强阳性表达率分别为0(0/20)、60%(12/20)和86%(36/42),PCa中PIM-1蛋白表达水平高于HGPIN和BPH(P值均〈0.05)。PIM-1蛋白表达水平随PCa的临床分期和病理分级增高而增强,在有和没有淋巴结转移PCa组织中PIM-1强阳性表达率分别为70%(7/10)、25%(8/32),差异有统计学意义(P〈0.05)。结论PIM-1高表达可能与PCa发生和发展相关,PIM-1表达水平与PCa分期、Gleason评分呈正相关,可能成为PCa预后判断的肿瘤标志物。  相似文献   
39.
通过8名健康志愿者服药后的对照实验,用微生物法检测血药浓度,按一室模型配置求算药物动力学参数,探讨西咪替丁对林可霉素体内过程的影响。结果表明,西咪替丁不能改变林可霉素的吸收速率(Ka)和消除速率(Ke),但可通过增加其吸收程度或改变其分布容积,使林可霉素的血药浓度和生物利用度分别增加约19%和27%。  相似文献   
40.
We used molecular modeling to examine the binding of 1, 2-dioctanoyl-sn-glycero-3-phosphocholine (a lecithin), 1-octanoyl-sn-glycero-3-phosphocholine (a lysolecithin) and their tetrahedral intermediates in the catalytic site of phospholipase A2 (PLA2). We performed energy minimization on each complex, computed the binding energy, determined the relative binding energy among the complexes and calculated the difference in inter- and intramolecular energies of the components in the complexes. We found that the calculated orientation of the sn-1 ester bond of lysolecithin in the active site is similar to that of the sn-2 ester bond in lecithin, thus permitting PLA2 to hydrolyze lysolecithin using the same mechanism as it uses to hydrolyze lecithin. On the other hand, the binding of lecithin is energetically more favorable by 4.5 kcal/mol than the binding of lysolecithin to the enzyme, and the binding of the lecithin tetrahedral intermediate is also energetically more favorable by 19.7 kcal/mol than the binding of the lysolecithin tetrahedral intermediate to the enzyme, which explains why lecithin is a better substrate than lysolecithin in the catalytic site. These results indicate that the activation energy for the hydrolysis of lysolecithin is higher than that for lecithin, consistent with the observed slower rate for the hydrolysis of lysolecithin.  相似文献   
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