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991.
目的探讨尿视黄醇结合蛋白(RBP)的变化在新生儿窒息后肾小管损伤中的意义及不同窒息程度新生儿尿RBP值随日龄的动态变化特点。方法对132例足月窒息新生儿(轻度窒息67例,重度窒息65例)和48例足月正常新生儿(对照组)在生后1、3、7、10天用酶联免疫吸附法监测尿RBP。结果①生后d.与对照组相比,窒息组尿RBP值显著升高(P〈0.001)。②重复测量资料方差分析显示,不同组别之间存在差异(P〈0.01),进一步用SNK检验,得出两两间的差异均有意义(P〈0.05)。③不同日龄3组新生儿尿RBP值变化的趋势不同(P〈0.01)。④重度窒息组尿RBP,、RBP,。值与对照组和轻度窒息组均有差异(P〈0.05)。结论①生后7天内新生儿肾小管功能发育不完善。对窒息新生儿应监测肾功能,特别是重度窒息需7—10天以上的肾功能随访。 相似文献
992.
Kallakuri S Cavanaugh JM Ozaktay AC Takebayashi T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,148(4):419-424
Diffuse axonal injury (DAI) is seen as widespread damage in the white matter of brain characterized by morphological changes
to axons throughout the brain and brain stem. The current study attempted to investigate the effect of increasing impact energy
on the presence and severity of DAI in corpus callosum (CC). DAI was induced in adult male Sprague-Dawley rats using an injury
model adapted from Marmarou et al. in 1994. A 450-g cylindrical brass weight was dropped from three different heights (2.0 m,
1.5 m and 1.0 m) on to a metal helmet affixed to the skull of the rats. In the sham group, rats underwent a surgical procedure
with no impact. After a 24-h survival period the animals were transcardially perfused. The brain was removed and the cerebral
hemispheres were sectioned with a vibrotome and stained by silver impregnation technique. The CC of all the impacted rats
showed DAI in the form of beaded axons, retraction balls and vacuole-like enlargements. The axonal injury was most severe
in the 2-m group, while mildest in the 1-m group. In the sham group, axons appeared to be normal. This study demonstrates
evidence of graded DAI depending on the impact energy. Such data is useful for mathematical modeling of axonal injury in rat
brain using the same impact parameters and potential determination of injury thresholds for neural trauma.
Electronic Publication 相似文献
993.
朱正桓邹红军宋志文刘锦波 《中国组织工程研究》2023,(1):114-120
背景:以往的研究显示单一改变脊髓损伤区域某一基因表达或者某一细胞的状态,对脊髓损伤后功能恢复无显著影响,而大量证据表明调控脊髓损伤后紊乱的细胞微环境是神经功能恢复的关键因素。目的:对脊髓损伤前后细胞微环境的生物学特性,包括多种细胞之间的相互调控以及细胞外组分对损伤神经修复的作用和机制进行综述。方法:由第一作者检索PubMed及Web of Science数据库,英文检索词为“spinal cord injury,glial cell,neuron,immune cell,neural stem cell,extracellular matrix,cytokine,extracellular vesicle,regeneration”。文献检索的时间范围为2000年1月至2021年12月,最终筛选出64篇文献进行分析。结果与结论:①脊髓损伤后,在细胞微环境的细胞组分中,占比最高的胶质细胞间的相互作用,以及与神经元的相互调控作用最为关键。②在脊髓损伤后的细胞外组分中,利用生物相容性良好的水凝胶模仿天然细胞外基质,可有效模拟和重建损伤区域内的细胞微环境,促进轴突伸长。③在脊髓损伤后的细胞外调节因子中,促炎因子如肿瘤坏死因子α和白细胞介素1β等加剧了细胞微环境的炎症反应,应用受体抑制剂或阻断相关通路抑制上述促炎因子的表达是一种有效的治疗方法,同时在脊髓微环境中增加白细胞介素10等抗炎因子的表达,抑制损伤区域炎症发展的研究也陆续出现。④最近被重视起来的细胞外囊泡作为传递信息的载体在细胞微环境中也发挥了重要作用。⑤文章揭示了脊髓损伤后细胞微环境中的包括细胞组分和细胞外组分之间的多组相互调控关系,证实了细胞微环境中各组分之间所发挥的神经修复作用并不是孤立的。 相似文献
994.
Umbilical cord blood of newborns and peripheral blood of healthy adults were investigated by an immunospot assay for cells secreting IgG, IgA and IgM antibodies against myelin basic protein (MBP), proteolipid protein (PLP), myelin-associated glycoprotein (MAG) and myelin oligodendrocyte glycoprotein (MOG) which represent putative antigens for an autoimmune attack in multiple sclerosis (MS) and against acetylcholine receptor (AChR) which is considered an important autoantigen in myasthenia gravis. Cells secreting antibodies against one or more of these autoantigens were detected in 18 out of 24 newborns, and in eight out of 20 adults. Eight of the cord blood samples contained cells secreting antibodies of IgG, IgA and/or IgM isotypes to one antigen, five to two antigens, two to three antigens, two to four antigens, and one to five antigens. Most prominent were anti-MBP IgG antibody secreting cells which were detected in 13 newborns at a mean number of 1/20,000 cord blood cells, and in six adults at a mean number of 1/10(5) peripheral blood cells. Anti-AChR IgG antibody secreting cells were detected in four out of 12 newborns versus four out of 14 peripheral blood specimens, at mean values of 1/10(5) cells in both instances. Cells secreting autoantibodies of IgA and IgM isotypes were less frequent both in cord blood and peripheral blood. The occurrence of nervous tissue autoantibody secreting cells in newborns must be related to a possible primary role of such autoantibodies in MS and myasthenia gravis. 相似文献
995.
996.
The relationship between the lumbosacral enlargement and the conus medullaris during the period of fetal development and adulthood 总被引:2,自引:0,他引:2
Malas MA Seker M Salbacak A Büyükmumcu M Karabulut AK Yardimci C 《Surgical and radiologic anatomy : SRA》2000,22(3-4):163-168
The spinal cord is situated within the vertebral canal by the third month of intrauterine life. The spinal cord possesses two symmetrical enlargements, which constitute the segments of the plexuses the cervical enlargement for the brachial plexus and the lumbosacral enlargement for the lumbar and sacral plexus. In our study, we aimed to investigate the relationship between the termination level of the lumbosacral enlargement (TLLE) and that of the conus medullaris (TLCM) during the period of fetal development and adulthood. We used a total of 75 cases 25 fetuses (male 16, female 9) whose crown-rump length ranged between 90–190 mm, 25 premature and full-term neonates (male 17, female 8) whose post-menstrual ages ranged between 33–55 weeks, and 25 adults (male 12, female 13) aged between 22–72 years. The dissection technique for fetuses, ultrasonography for premature and full-term newborns, and magnetic resonance imaging (MRI) for adults were used to determine lumbosacral enlargement and TLCM. The differences between the TLCM and the termination level of the largest part of the transverse diameter of the lumbosacral enlargement were investigated. The differences between the TLLE and TLCM were found in different ratios from the period of fetal development to adulthood. Therefore, during medical treatment and surgical procedures this should be taken into account to avoid complications. 相似文献
997.
醛糖还原酶是糖代谢多元醇通路的限速酶。最新研究表明:心肌缺血时醛糖还原酶活性增强,抑制醛糖还原酶可以通过保护糖酵解途径和抑制氧化应激,减轻心肌缺血损伤,改善缺血再灌注后心肌功能。醛糖还原酶抑制剂作为潜在的治疗心肌梗死的有效措施引起了研究者的关注。 相似文献
998.
目的研究深圳市特区外劳务工颅脑损伤流行病学特点及处理对策。方法回顾2880例特区外劳务工颅脑损伤病例,对姓名、年龄、性别、受伤原因和时间、医疗费来源、知情同意书签署、损伤类型、治疗方法和结果等因素进行分析。结果特区外劳务工颅脑损伤的救治与年龄、性别、损伤类型、治疗方法和结果等因素相关外,还与姓名、受伤原因和时间、医疗费来源、知情同意书签署等因素相关。结论外来劳务工本身是深圳的弱势群体,受伤后更需要政府和社会的理解和支持,相关部门制定一套完善的预防及救治策略很有必要。 相似文献
999.
D. Nozaki K. Nakazawa Y. Yamamoto 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,112(1):112-118
In our previous study,
-type power spectrum with the spectral exponent significantly greater than zero was found in the variability of soleus H-reflex amplitudes. This result indicated that the H-reflex variability was time-correlated owing to fractal characteristics. Furthermore, it was also suggested that the fractal characteristics were generated at the spinal level. The purpose of the present study was to investigate whether the fractal nature of the H-reflex variability was influenced by the loss of supraspinal input. Six healthy normal subjects and seven patients with spinal cord injury participated in this study. Soleus H-reflexes were evoked every l s from both legs simultaneously (stimulation intensity: motor threshold) and 1050 successive amplitudes of the H-reflex were recorded. The H-reflex sequence evoked from each leg was analyzed by coarse graining spectral analysis to calculate the spectral exponent . The value of was used to evaluate the level of time-correlation (fractal correlation). Cross-spectral analysis was used to evaluate the degree of synchronization between the H-reflex sequences evoked from both legs. The values for normal subjects (0.84±0.33, left leg; 0.88±0.34, right leg) were significantly greater (P<0.001) than those for patients (0.31±0.18, left leg; 0.32±0.14, right leg), suggesting that the H-reflex sequences for normal subjects were more time-correlated than for patients. In the frequency range less than 0.2 Hz, the coherence of both legs was high (0.41±0.14) for normal subjects as compared to 0.20±0.12 for patients (P<0.005). In this frequency range, the phase was almost 0 rad for normal subjects, indicating that the H-reflex variabilities of both legs were synchronized. These results suggested that (1) the strong fractal correlation observed in the H-reflex sequences for normal subjects was associated with supraspinal input, and (2) such supraspinal input had equal influence on the reflex arcs of the soleus of both legs. 相似文献
1000.
Myung Ha Yoon Kyung Deok Park Hyung Gon Lee Woong Mo Kim Tae Hoon An Yeo Ok Kim Lan Ji Huang Cui Jin Hua 《Journal of Korean medical science》2008,23(6):1033-1038
The possible characteristics of spinal interaction between sildenafil (phosphodiesterase 5 inhibitor) and morphine on formalin-induced nociception in rats was examined. Then the role of the opioid receptor in the effect of sildenafil was further investigated. Catheters were inserted into the intrathecal space of male Sprague-Dawley rats. For induction of pain, 50 µL of 5% formalin solution was applied to the hind-paw. Isobolographic analysis was used for the evaluation of drug interaction between sildenafil and morphine. Furthermore, naloxone was intrathecally given to verify the involvement of the opioid receptor in the antinociception of sildenafil. Both sildenafil and morphine produced an antinociceptive effect during phase 1 and phase 2 in the formalin test. The isobolographic analysis revealed an additive interaction after intrathecal delivery of the sildenafil-morphine mixture in both phases. Intrathecal naloxone reversed the antinociception of sildenafil in both phases. These results suggest that sildenafil, morphine, and the mixture of the two drugs are effective against acute pain and facilitated pain state at the spinal level. Thus, the spinal combination of sildenafil with morphine may be useful in the management of the same state. Furthermore, the opioid receptor is contributable to the antinocieptive mechanism of sildenafil at the spinal level. 相似文献