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51.

Background

Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity.

Case presentation

A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone.

Conclusion

Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans.  相似文献   
52.
以狭果茶藨子果实为原料,多糖提取量为考察指标,通过单因素试验及响应面试验对多糖提取工艺进行优化,结果表明最佳多糖制备工艺条件为:提取温度40℃,时间30 min,料液比1∶30 g/mL,此时狭果茶藨子中多糖提取量达115.32 mg/g;流变学特性研究表明狭果茶藨子果实多糖溶液属于非牛顿流体,多糖溶液表现出剪切稀化的现象,当多糖质量浓度为1.0%时,其流变学特性与0.1%的羧甲基纤维素钠溶液相似,且过酸、过碱的环境均不会改变狭果茶藨子果实多糖溶液的流变学特性;抗氧化试验结果表明狭果茶藨子果实多糖具有潜在的抗氧化能力,对DPPH自由基的清除能力低于抗坏血酸,而对羟自由基的清除能力显著高于抗坏血酸。本研究结果可为狭果茶藨子果实多糖在食品领域的开发利用提供理论依据。  相似文献   
53.

Background and aims

Osteoporosis, which is a disease characterized by weakening of the bone, affects a large portion of the senior population. The current therapeutic options for osteoporosis have side effects, and there is no effective treatment for severe osteoporosis. Thus, we urgently need new treatment strategies, such as topical therapies and/or safe and effective stem cell therapies.

Methods

We investigated the therapeutic potential of directly injecting human tonsil-derived mesenchymal stem cells (TMSC) into the right proximal tibias of ovariectomized postmenopausal osteoporosis model mice. Injections were given once (1×) or twice (2×) during the 3-month experimental period. At the end of the experiment, micro-computed tomographic images revealed some improvement in the proximal tibias and more significant improvement in the femoral heads of treated mice.

Results

Osteogenic effect was qualitatively and quantitatively more pronounced in TMSC/2×-treated mice. Furthermore, TMSC/2×?mice exhibited significant recovery of the serum osteocalcin level, which is pathologically elevated in osteoporosis, and increased serum alkaline phosphatase, which indicates bone formation. TMSC therapy was generally well tolerated and caused no apparent toxicity in the experimental mice. Moreover, TMSC therapy reduced visceral fat.

Conclusion

Our results demonstrate that double injection of TMSC directly into the proximal tibia triggers recovery of osteoporosis, and thus could be a potential therapeutic approach for severe bone loss.  相似文献   
54.
目的:观察诱导型一氧化氮合酶(iNOs)基因Ser608Leu位点基因多态性与2型糖尿病的相关性。方法:采用测序法测定261例2型糖尿病患者和128例正常对照者iNOS基因Ser608Leu位点基因多态性。结果:两组间iNOS基因Ser608Leu位点基因型及等位基因频率构成存在差异。结论:iNOS基因Ser608Leu位点多态性与2型糖尿病有关。  相似文献   
55.
In this paper we describe a novel approach that may shed light on the genomic DNA methylation of organisms with non‐resolved genomes. The LUminometric Methylation Assay (LUMA) is permissive for genomic DNA methylation studies of any genome as it relies on the use of methyl‐sensitive and ‐insensitive restriction enzymes followed by polymerase extension via Pyrosequencing technology. Here, LUMA was used to characterize genomic DNA methylation in the lower brain stem region from 47 polar bears subsistence hunted in central East Greenland between 1999 and 2001. In these samples, average genomic DNA methylation was 57.9% ± 6.69 (SD; range was 42.0 to 72.4%). When genomic DNA methylation was related to brain mercury (Hg) exposure levels, an inverse association was seen between these two variables for the entire study population (P for trend = 0.17). After dichotomizing animals by gender and controlling for age, a negative trend was seen amongst male animals (P for trend = 0.07) but no associations were found in female bears. Such sexually dimorphic responses have been found in other toxicological studies. Our results show that genomic DNA methylation can be quantitatively studied in a highly reproducible manner in tissue samples from a wild organism with a non‐resolved genome. As such, LUMA holds great promise as a novel method to explore consequential questions across the ecological sciences that may require an epigenetic understanding.  相似文献   
56.
Germination of primary dormant barley grains is promoted by darkness and temperatures below 20 °C, but is strongly inhibited by blue light. Exposure under blue light at 10 °C for periods longer than five days, results in a progressive inability to germinate in the dark, considered as secondary dormancy. We demonstrate that the inhibitory effect of blue light is reinforced in hypoxia. The inhibitory effect of blue light is associated with an increase in embryo abscisic acid (ABA) content (by 3.5‐ to 3.8‐fold) and embryo sensitivity to both ABA and hypoxia. Analysis of expression of ABA metabolism genes shows that increase in ABA mainly results in a strong increase in HvNCED1 and HvNCED2 expression, and a slight decrease in HvABA8′OH‐1. Among the gibberellins (GA) metabolism genes examined, blue light decreases the expression of HvGA3ox2, involved in GA synthesis, increases that of GA2ox3 and GA2ox5, involved in GA catabolism, and reduces the GA signalling evaluated by the HvExpA11 expression. Expression of secondary dormancy is associated with maintenance of high embryo ABA content and a low HvExpA11 expression. The partial reversion of the inhibitory effect of blue light by green light also suggests that cryptochrome might be involved in this hormonal regulation.  相似文献   
57.

Introduction  

Articular tissues are capable of producing a range of eicosanoid mediators, each of which has individual biological effects and may be affected by anti-inflammatory treatment. We set out to develop and evaluate a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) approach for the simultaneous analysis of multiple eicosanoid lipid mediators in equine synovial fluid (SF), and to illustrate its use for investigation of the in vivo effects of non-steroidal anti-inflammatory drug (NSAID) treatment.  相似文献   
58.
59.
The bias of estimators of causal spatial autoregressive processes   总被引:1,自引:0,他引:1  
HA  EUNHO; NEWTON  H. JOSEPH 《Biometrika》1993,80(1):242-245
  相似文献   
60.
利用植物木质纤维资源发酵产乙醇越来越受到人们的重视,但是要达到工业生产仍然存在很多难题。最近在利用植物基因工程技术改善植物自身性状,以利于能源植物的研究方面取得了一定的进展,这些研究包括减少植物自身细胞壁中的木质素含量、细胞中积累表达纤维素酶和木聚耱酶等的方法,使产生的生物质更利于降解利用。  相似文献   
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