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为了探讨周围神经组织环境因素对EPI-NCSCs(epidermalneuralcreststemcells)分化的影响,该文用坐骨神经组织提取液为环境因素,对体外培养的EPI—NCSCs进行分化诱导。以正常培养的EPI—NCSCs为对照组,细胞培养液成分为:DMEM/F12、10%FBS、2%B27、20ng/mLbFGF。在细胞培养液中添加1%周围神经组织液作为实验组。MTT结果显示。周围神经组织液对EPI-NCSCs的活性和增殖无影响;对照组和实验组EPI-NCSCs都呈多种形态。RT-PCR分析显示,在对照组和实验组中EPI.NCSCs均表达GFAP、S-100、β-IIITubulin(Tujl),但在实验组中,这3种蛋白的表达量均高于对照组。免疫组化分析显示,在对照组中,EPI—NCSCs同时表现了雪旺细胞和早期神经元的鉴定特征;在实验组中,EPI—NCSCs没有神经元的鉴定特征,只表达雪旺氏细胞的鉴定特征。这表明,周围神经组织液可以诱导体外培养的EPI-NCSCs向雪旺氏细胞分化。  相似文献   

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This paper examines the impact of two important geometrical parameters, namely the thickness and source/drain extensions on the performance of low doped p-type double lateral gate junctionless transistors (DGJLTs). The three dimensional Technology Computer-Aided Design simulation is implemented to calculate the characteristics of the devices with different thickness and source/drain extension and based on that, the parameters such as threshold voltage, transconductance and resistance in saturation region are analyzed. In addition, simulation results provide a physical explanation for the variation of device characteristics given by the variation of geometric parameters, mainly based on investigation of the electric field components and the carries density variation. It is shown that, the variation of the carrier density is the main factor which affects the characteristics of the device when the device''s thickness is varied. However, the electric field is mainly responsible for variation of the characteristics when the source/drain extension is changed.  相似文献   

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Kidney cortex slices incubated in vitro at 0°C. accumulate radiosulfate from the incubation medium. This process differs from the previously described uptake of radiosulfate by renal tissue incubated at 38°C., for instance, in the lesser sensitivity of the uptake at 0°C. to differential effects of Na+ as compared with K+ ions, and of sucrose as compared with glucose. Phlorizin inhibits radiosulfate accumulation at 0°C., whereas it enhances the uptake at 38°C. Effects of the cations K+ and Na+ and of phlorizin at temperatures intermediate between 0° and 38°C. have been studied. Parallels have been noted between the accumulative processes for radiosulfate of kidney slices maintained at 0°C. and of mitochondria isolated from rat liver and kidney cortex. These similarities may be attributed to an important role of radiosulfate uptake by mitochondria in slice accumulation of radiosulfate in the cold.  相似文献   

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目的:研究红细胞形态学参数对心肌梗死患者诊断作用及其与心肌酶谱的相关性。方法:选取40例心肌梗死患者,40例稳定型心绞痛组患者,40例健康对照组人群。对比分析稳定性心绞痛、急性心肌梗死(入院1h内)和对照组红细胞形态学参数(MCV、MCH、MCHC、RDW)、及心肌酶谱(CK-MB、c Tn I)。分析心肌梗死不同时间MCV、MCH、MCHC、RDW变化趋势。结果:稳定性心绞痛、心肌梗死组1 h内MCV、RDW明显高于正常对照组,差异有统计学意义(P0.05);稳定性心绞痛、心肌梗死组1 h内MCHC、MCH低于对照组,差异有统计学意义(P0.05)。心肌梗死组MCV、RDW在发病后1 h、24 h、48 h、7 d水平逐渐升高,各时间点间差异有统计学意义(P0.05)。心肌梗死组发病后1 h、24 h、48 h、7 d、14 d MCHC、MCH水平逐渐降低,各时间点间差异有统计学意义(P0.05)。RDW和CK-MB、c Tn I呈正相关性(P0.05)。RDW对心肌梗死诊断的灵敏度最高达到93.4%,特异度为69.7%,RDW对急性心肌梗塞的诊断临界值为14.04%。结论:RDW对心肌梗死的诊断具有较高的敏感性,可用于临床早期诊断心肌梗死,为临床诊断提供一新的诊断标准。  相似文献   

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在培养的人心肌细胞上研究了黄芪、人参抗Cox B-3及Echo-19病毒的作用及诱生干扰素的效应,结果表明两种药物分别作用于人心肌细胞48小时及感染病毒的心肌细胞在含药物的营养液中培养均可降低细胞对两种病毒感染的敏感性,此作用与药物诱导心肌细胞产生IFN有关。  相似文献   

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The aim of this study was to examine the effects of sucrose, dextran, polyethylene glycol, glycerol, and mannitol, which possess cryoprotective properties to various degrees, on the mechanical stability and the geometric parameters of human erythrocytes. All substances, except mannitol, contributed to a decrease in hemolysis, which was caused by the movement of small beads. Glycerol and polyethylene glycol, which provide the highest level of protection of erythrocytes during cryopreservation, also showed the maximum efficiency under mechanical stress. Changes in cell resistance may be associated with the transformation of their geometric parameters. According to the cytometry data, 5% solutions of all the substances, except mannitol, caused similar changes in the geometric parameters of the cell. The relationship between changes in the mechanical stability and the geometric parameters of erythrocytes under the influence of cryoprotective agents may be caused by the modification of the membrane?cytoskeleton protein complex, which controls the mechanoelastic properties and morphology of erythrocytes.  相似文献   

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A variety of foods have been implicated in symptoms of patients with Irritable Bowel Syndrome (IBS) but wheat products are most frequently cited by patients as a trigger. Our aim was to investigate the effects of breads, which were fermented for different lengths of time, on the colonic microbiota using in vitro batch culture experiments. A set of in vitro anaerobic culture systems were run over a period of 24 h using faeces from 3 different IBS donors (Rome Criteria–mainly constipated) and 3 healthy donors. Changes in gut microbiota during a time course were identified by fluorescence in situ hybridisation (FISH), whilst the small -molecular weight metabolomic profile was determined by NMR analysis. Gas production was separately investigated in non pH-controlled, 36 h batch culture experiments. Numbers of bifidobacteria were higher in healthy subjects compared to IBS donors. In addition, the healthy donors showed a significant increase in bifidobacteria (P<0.005) after 8 h of fermentation of a bread produced using a sourdough process (type C) compared to breads produced with commercial yeasted dough (type B) and no time fermentation (Chorleywood Breadmaking process) (type A). A significant decrease of δ-Proteobacteria and most Gemmatimonadetes species was observed after 24 h fermentation of type C bread in both IBS and healthy donors. In general, IBS donors showed higher rates of gas production compared to healthy donors. Rates of gas production for type A and conventional long fermentation (type B) breads were almost identical in IBS and healthy donors. Sourdough bread produced significantly lower cumulative gas after 15 h fermentation as compared to type A and B breads in IBS donors but not in the healthy controls. In conclusion, breads fermented by the traditional long fermentation and sourdough are less likely to lead to IBS symptoms compared to bread made using the Chorleywood Breadmaking Process.  相似文献   

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肌肽对离体培养的鸡肝细胞的影响   总被引:1,自引:0,他引:1  
研究了肌肽对离体培养的鸡肝细胞的影响。实验采用胶原酶原位二步灌流法获得鸡肝细胞,再用不同浓度的肌肽(①2 μmol L、②2 0 μmol L、③2 0 0 μmol L ,④2 0mmol L)分别进行处理。结果表明,1 )在各个时期,含2 0 μmol L肌肽的实验组肝细胞生长均好于对照组(0 μmol L肌肽) ,而且在48和72h时二者差异显著(P <0 0 5 ) ;2 ) 2 0mmol L肌肽能显著提高肝细胞的分泌白蛋白的功能(P <0 0 5 ) ;3 )添加肌肽的各实验组上清液中丙二醛(MDA)含量在2 4和48h时均低于对照组;4)添加2 0mmol L肌肽的实验组与对照组相比,能维持无血清培养肝细胞的形态达8d。表明了肌肽对鸡肝细胞增殖和分泌白蛋白有促进作用,同时可以保护肝细胞对抗过氧化,保护细胞形态。  相似文献   

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In Vitro Effects of Some Chemotherapeutic Agents on Mycobacteria   总被引:1,自引:1,他引:0       下载免费PDF全文
Examination of the bactericidal and bacteriostatic effects of nine antibiotics on atypical mycobacteria revealed that streptovaricin complex and streptovaricin C exerted bactericidal effects on several strains in concentrations lower than 1.0 mug/ml. An exposure to the drug for 48 hr at 37 C was necessary to effect a complete inactivation of more than 99.9% of the exposed microorganisms. The appearance of strepto-varicin-resistant mutants was observed. However, these mutants were unstable, and reversion to streptovaricin susceptibility occurred. Celesticetin salicylate, added in a concentration of 100.0 mug/ml to the medium of Olitzki and Gershon inoculated with Mycobacterium leprae, effected a complete change of the uniformly stained mycobacteria to bipolarity, which indicates the devitalization of this microorganism.  相似文献   

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Purpose

We evaluated the effect of different water immersion (WI) temperatures on post-exercise cardiac parasympathetic reactivation.

Methods

Eight young, physically active men participated in four experimental conditions composed of resting (REST), exercise session (resistance and endurance exercises), post-exercise recovery strategies, including 15 min of WI at 15°C (CWI), 28°C (TWI), 38°C (HWI) or control (CTRL, seated at room temperature), followed by passive resting. The following indices were assessed before and during WI, 30 min post-WI and 4 hours post-exercise: mean R-R (mR-R), the natural logarithm (ln) of the square root of the mean of the sum of the squares of differences between adjacent normal R–R (ln rMSSD) and the ln of instantaneous beat-to-beat variability (ln SD1).

Results

The results showed that during WI mRR was reduced for CTRL, TWI and HWI versus REST, and ln rMSSD and ln SD1 were reduced for TWI and HWI versus REST. During post-WI, mRR, ln rMSSD and ln SD1 were reduced for HWI versus REST, and mRR values for CWI were higher versus CTRL. Four hours post exercise, mRR was reduced for HWI versus REST, although no difference was observed among conditions.

Conclusions

We conclude that CWI accelerates, while HWI blunts post-exercise parasympathetic reactivation, but these recovery strategies are short-lasting and not evident 4 hours after the exercise session.  相似文献   

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KUMRA  P. K. 《Annals of botany》1982,50(6):771-777
The present work deals with the effect of the chelating agentsethylenediamine-di(o-hydroxyphenylacetic acid) [EDDHA] ethylenediamine tetra acetic acid [EDTA] and their iron salts, salicylicacid and ferric citrate on growth and antheridial productionin male clones of three dioecious mosses: Barbula gregaria,Bryum coronatum and Philonotis turneriana., Barbula and Bryumdevelop antheridia in ordinary cultural conditions on basalmedium, whereas Philonotis remains sterile. In Barbula and BryumEDDHA and EDTA enhance the percentage of fertile gametophytes.Fe-EDDHA and Fe-EDTA increase antheridial production as wellas vegetative growth and the former effect is more striking.In this respect Fe-EDDHA is better than Fe-EDTA for Barbula,whereas the reverse is true for Bryum. Salicylic acid inhibitsantheridial production and vegetative growth. Ferric citrateenhances vegetative growth in all three mosses. In Barbula andBryum it also stimulates antheridial production, and this effectis more marked than that on vegetative growth. None of the chelatestested induces antheridia in Philonotis. antheridial production, Barbula gregaria (Mitt.) Jaeg., Bryum coronatum Schwaegr., Philonotis turneriana (Schwaegr.) Mitt., mosses, chelating agents, bryophyta  相似文献   

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The concentration of antibacterial agents in the interstitial tissue fluid has been studied in an experimental model using implanted perforated Silastic capsules (tissue cages). Tissue fluid concentrations were always lower than the initial peak concentration in the serum, but for those drugs that were more slowly excreted the tissue fluid was similar to the serum concentration after six hours. In contrast the concentration in the tissue fluid for those drugs that are excreted rapidly was unpredictable, being either negligible or maintained at concentrations significantly better than in the serum. There was no evidence of accumulation in tissue fluid with regular dosage. These results indicate that the tissues may never be exposed to an adequate concentration of some antibacterial agents. This may be of clinical importance in tissue infections. Antibiotics which are rapidly excreted should be given in large enough doses and often enough for adequate blood levels to be maintained, so allowing equilibrium with tissue fluid to be achieved.  相似文献   

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Results of laboratory and field tests suggest that chelating agents could be used to alleviate adverse soil properties caused by excess sodium, such as low permeability. Adding multi-dentate carboxylic acid chelating agents to sodic soil, or to mixtures of soil with sodium-contaminated waste, significantly reduced sodium adsorption ratio (SAR) values. Judging from cation concentrations in saturated paste (sat. paste) filtrates, chelating agents act to ameliorate soil sodicity by releasing Ca and to a lesser extent Mg from undissolved compounds. After adding chelating agents to moist soils that contained free lime, measured weight losses were consistent with CO 2 evolution due to CaCO 3 decomposition. The electrical conductivity (EC) of the sat. paste filtrate of materials treated with chelating agents increased less than when equivalent Ca or Mg was supplied in conventional, soluble form. Bigger sat. paste vacuum filtration volumes, improved soil permeability and faster field infiltration rates were observed after treatment with chelating agents. The Ca- and Mg-complexes of agents such as citric and malic acid degrade in moist soil; such agents could perhaps be used in a series of applications to improve ease of cultivation and permeability of cropped land. The agent ethylenediamine tetraacetic acid (EDTA) forms stable complexes, and could therefore be used as a one-time treatment for sodic materials that are to be disposed of by burial, following guidelines for soil SAR and EC.  相似文献   

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Reperfusion injury causes oxidative stress thereby resulting in an imbalance between oxidant-antioxidant systems. In the present communication, the effect of ascorbic acid supplementation has been studied on certain oxidant and antioxidant parameters in the blood of the patients with myocardial infarction before and after thrombolysis. In patients after thrombolysis, the activity of antioxidant enzyme, superoxide dismutase, in the blood was found to be significantly reduced where as the activity of the oxidant enzyme, xanthine oxidase, was found to be significantly increased. Malondialdehyde levels, the index of free radical mediated damage, was also found to be significantly elevated in thrombolyzed patients compared to the patients before thrombolysis. Supplementation of vitamin C to the post reperfusion patients restored these parameters back to normal or near normal levels.  相似文献   

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The administration of nembutal and chloral hydrate anesthetic agents in the rat produces an increase in the uptake of zinc, as Zn-65, in the liver. Associated with this is the appearance of a low-molecular-weight Zn-binding protein in the soluble cytosol fraction. This protein is comparable to that induced by the stress of severe exercise, by burn injury, and by Zn injection, and is probably Zn metallothionein. This is an example of the induction of a Zn binding protein in the liver by a drug, and confirms that anesthesia significantly effects Zn metabolism in the liver. Consequently this effect of anesthetic agents should be taken into account in the investigation of the regulation of Zn metabolism.  相似文献   

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