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21.
蛋白质组学是研究细胞内所有蛋白质及其动态变化规律的科学,近年来它被广泛应用于生命科学的各个领域.二维聚丙烯酰胺凝胶电泳法(2D PAGE)是蛋白质组学核心技术.就蛋白质组学在皮肤病学基础研究和临床皮肤病中的应用进行综述. 相似文献
22.
Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies. 相似文献
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24.
U. Logonder Z. Jenko-Pranikar T. Scott-Davey J. Punger
ar I. Kriaj J.B. Harris 《Experimental neurology》2009,219(2):591-594
A mutant form of ammodytoxin A, a neurotoxic phospholipase A2 from the venom of the long nosed viper Vipera ammodytes ammodytes, was prepared by site-directed mutagenesis, conjugated to a nanogold particle and inoculated into the antero-lateral aspect of one hind limb of female mice. Eight hours later the mice were killed, the soleus muscles of both ipsi- and contra-lateral hind limbs were removed, exposed to a silver enhancing medium and then prepared for transmission electron microscopy. Silver-enhanced particles were subsequently found concentrated in the peri-synaptic area, particularly within the synaptic gutter and the deep synaptic folds, and in many cases had been taken up into the cytoplasm of the terminal boutons of the motor axon. The results suggest that the presynaptic neurotoxicity of snake venom phospholipases A2 involves several components of the neuromuscular apparatus, including intracellular organelles of the motor nerve terminal. 相似文献
25.
HELENA MARKKANEN STINA M. SYRJÄNEN PEKKA ALAKUIJALA 《European journal of oral sciences》1986,94(2):115-120
Abstract — The concentrations of IgA, lysozyme and β-microglobulin (β2 -m) were quantitated in wax-stimulated mixed saliva from 28 patients with severe periodontitis and from 28 healthy controls. The mutual correlations between IgA, lysozyme and β2 -rn were determined. In patients with periodontitis decreased lysozyme concentrations were detected when compared with controls (P<0.05). The correlation between IgA and β2 -m concentrations was highly significant in both groups studied (P<0.0001, and P <0.002), whereas β2 -m and lysozyme concentrations were positively correlated in patients but not in controls. In addition, a significant correlation between IgA and lysozyme was found only in periodontal patients ( P <0.001). 相似文献
26.
Objective To investigate the best way to control the blood sugar level during the perioperation of bone fracture patients with type 2 diabetes(T2DM).Methods Bone fracture patients with T2DM were randomly divided into three groups:continuous subcutaneous insulin infusion group(insulin aspart,group CSII,n=20),glargine treatment group(insulin aspart+insulin glargine,group GA,n=20),and NPH treatment(insulin aspart+rh-insulin,group NA,n=20).The levels of fasting plasma glucose(FPG)and the 2 hours postprandial glucose(2h PG),blood glucose fluctuation(BGF),insulin dosage(ID),good effective time(GET),incidence of hypoglycemia,dawn phenomenon and infection,average time of stitches removal(ATSR),average hospitalized length(AHL)of three groups were compared.Results FPG and 2hPG,ID in group CSII[(6.32±1.18)mmol/L,(7.72±1.53)mmol/L,(35.40±1.60)IU]and group GA [(6.25±0.88)mmol/L,(7.32±1.17)mmol/L,(36.20±0.80)IU]were significantly lower than those of group NA [(7.44±1.36)mmol/L,(8.52±0.76)mmol/L,(40.50±2.40)IU,all P<0.05],simulaneously,BGF,GET incidence of complications,ATSR,AHL of group CSII and GA were significantly lower than those of group NA(all P<0.05).There were not significant difference between group CSII and group GA.Compared with group CSII,group GA had less costs in-hospital and better practicability.Conclusion Both CSII and insulin glargine combined with insulin aspart can effectively,safely,rapidly and stablely control hyperglycemia.and might be the first choice to control blood sugar for bone fracture patients with T2DM in perioperation. 相似文献
27.
X Dong M He X Song B Lu Y Yang S Zhang N Zhao L Zhou Y Li X Zhu R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks. 相似文献
28.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(6):531-537
Exposure of captodative enone systems to deuterium in the presence of Crabtree's catalyst ( 1 ) results in deuteration at the vinylic site β‐ to the ketone carbonyl, as well as at any accessible ortho‐position. β‐exchange is also observed during the reduction of ethyl cinnamate ( 3 ) catalyzed by 1 . Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
29.
30.
Giorgio Ciprandi Mara De Amici Simone Negrini Gianluigi Marseglia Maria Angela Tosca 《International immunopharmacology》2009,9(10):1247-1249
Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels. 相似文献