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871.
Locomotor strategies before independent walking: prospective study of 50 mentally retarded children.
To investigate the association between pre-walking locomotor strategies and psychomotor developments in children with mental retardation (MR), 50 children with non-specific MR were included in this study. There were 29 boys and 21 girls, 96% of whom had moderate to severe MR. They were followed from 4-53 months to 25-99 months of age, and their follow-up periods ranged from 10 to 48 months (mean 30 months). According to the pre-walking locomotor strategies, these children were categorized into three groups: the crawling group (n = 34) who used crawling or creeping as their main locomotion pattern before independent walking; the shuffling group (n = 9) who used shuffling prior to independent walking; and the direct-walking group (n = 7) who did not have any other locomotor strategies except rolling. In almost all motor developmental milestones, children in the direct-walking group developed earlier than those in the crawling and shuffling groups. Children in the crawling group had more advanced developments than those in the shuffling group. The difference in the mean ratio developmental quotients of the Bayley Mental Scale among the three groups was not significant. The present study showed that crawling may not be a necessary prerequisite for early ambulation or better cognitive function in MR children. 相似文献
872.
873.
用差速离心方法分离提取荷Lewis肺癌小鼠癌组织和肝组织富含溶酶体部分,并以溶酶体标志酶酸性磷酸酶(ACP)的游离酶和总酶活性比值作为观察溶酶体膜稳定性变化的指标,观察了亚硒酸钠对两种组织ACP酶活性和膜稳定性的影响。发现硒对癌组织和肝组织ACP活性的异常升高有抑制作用、稳定溶酶体膜,在癌瘤增殖前期作用明显(P<0.05)。提示这种拮抗效应与硒直接和间接的抗脂质过氧化有关。 相似文献
874.
Butyrate infusions in the ovine fetus delay the biologic clock for globin gene switching. 总被引:4,自引:0,他引:4 下载免费PDF全文
S P Perrine A Rudolph D V Faller C Roman R A Cohen S J Chen Y W Kan 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(22):8540-8542
The switch from fetal to adult hemoglobin expression is regulated in many mammalian species by a developmental clock-like mechanism and determined by the gestational age of the fetus. Prolonging fetal globin gene expression is of considerable interest for therapeutic potential in diseases caused by abnormal beta-globin genes. Butyric acid, which is found in increased plasma concentrations in infants of diabetic mothers who have delayed globin gene switching, was infused into catheterized fetal lambs in utero during the time of the normal globin gene switch period. The globin gene switch was significantly delayed in three of four butyrate-treated fetuses compared with controls and was entirely prevented in one fetus in whom the infusion was begun before the globin switch was under way. These data provide a model for investigating and arresting the biologic clock of hemoglobin switching. 相似文献
875.
The effects of zymosan-activated plasma(ZAP)on lung fluid exchangeand on superoxide anion production by granulocytes were studied in 8 consciousgoats with chronic lung lymph fistula,It was found that after ZAP infusion, thecirculating granulocytes were activated and the release of superoxide anions wasmarkedly enhanced. There was an increase in lung lymph flow and proteinconcentration.It suggests that the superoxide anion released by the stimulatedgranulocytes can play a role in inducing lung injury by the activated complement. 相似文献
876.
Recent advances in the investigation of liver disease and transplantation have seen the introduction of lignocaine as a probe of liver function. For this purpose, an assay that is sensitive and rapid is required for the major metabolite of lignocaine, monoethylglycinexylidide (MEGX). We have developed an accurate, low-cost high-performance liquid chromatography (HPLC) method using Bond-Elut phenyl (1 cc) cartridges for sample preparation. The total preparation time for five samples is less than 10 min and the run time is approximately 10 min/sample. Each cartridge can be used at least four times. Simultaneous measurement of another metabolite of lignocaine, glycinexylidide (GX), can be achieved by adjustment of the mobile phase and flow rate. The chromatogram is monitored with an UV detector at 210 nm. The inter- and intra-assay coefficients of variation for MEGX (10-250 micrograms/L) and lignocaine (100-2,000 micrograms/L) are less than 9.5 and less than 2%, respectively, with recoveries for MEGX, trimethoprim (internal standard), and lignocaine all greater than 85%. This method offers a rapid, sensitive assay that is clinically useful in the new role for lignocaine/MEGX in dynamic liver function testing. 相似文献
877.
大肠癌旁粘膜细胞的PCNA和AgNORs表达观察 总被引:2,自引:0,他引:2
用增殖细胞核抗原(PCNA)和核仁组成区嗜银蛋白(AgNORs)对35例大肠癌旁粘膜进行细胞增殖表达与观察。结果表明:癌旁粘膜的PCNA标记指数增多,标记增强,排列紊乱。AgNORs在癌旁粘膜中,颗粒增多、增大,形态多样,0 ̄1cm和2 ̄3cm组的标记指数与4 ̄5cm组的标记指数相比较,有显著或非常显著差异(P〈0.05或P〈0.01)。在DukeA、B期中,细胞标记指数增高增强,与癌的发生和患者 相似文献
878.
烧伤患者吸入性损伤和肺部感染的发生特点及其对死亡的影响 总被引:3,自引:0,他引:3
为了评价吸入性损伤和肺部感染的发生特点及其对死亡的影响,总结了我科近14年住院治疗的热力烧伤患者940例,其中吸入性损伤75例,轻度15例,全部治愈,中度25例,死亡13例,死亡率为52.0%,重度35例,死亡31例,死亡率为88.6%。统计分析表明,合并吸入性损伤者69.3%在密闭空间发生,同时伴有面部烧伤者达96.0%。随着烧伤面积的增加,吸入性损伤发生率和肺部感染的发生率相应增加。有吸入性损伤肺部感染较无吸入性损伤肺部感染率为高(P<0.01),发生时间早。两组同等烧伤面积、深度、年龄患者,有吸入性损伤组发生死亡的危险比无吸入性损伤组大17.2倍(P<0.001)。烧伤面积、深度和年龄相近,合并肺部感染者明显增加了死亡的机会(P<0.001)。 相似文献
879.
对中国药典附子中乌头硷限量检查的商榷 总被引:8,自引:0,他引:8
用高效液相色谱法测定生附子。炮制附片中的乌头硷、中乌头硷和次乌头硷含量,以及3种生物硷的水解速度,发现炮制附片中主要含次乌头硷,而药典只限定乌头硷含量,显得不够完善。故在此基础上探讨了药典中增加次乌头硷含量限定内容的可能性。 相似文献
880.
Until now methods using tetramethylbenzidine (TMB) for electron microscopy (TMB-EM methods) are all unable to provide a maximum demonstration of transported horseradish peroxidase (HRP) while maintaining good ultrastructural tissue preservation. In order to solve this problem, we have attempted to adapt a newly developed, highly sensitive TMB method using sodium tungstate (ST) as the stabilizer (TMB-ST method) for HRP electron microscopic retrograde and anterograde fiber tracing. The present study shows that the TMB-ST method combined with diaminobenzidine-cobalt (DAB-Co) is more sensitive than existing TMB-EM methods and that ultrastructural details are well preserved with this combined method. The resultant reaction product complex after osmication is stable and is observed as characteristic crystal-like structures which are extremely electron dense and often aggregated into clumps. In contrast, the TMB-ST method without the DAB-Co step frequently produces a moderate electron-dense reaction product. Therefore, we recommend the TMB-ST method combined with DAB-Co for HRP electron microscopy. 相似文献