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1.
OBJECTIVE: To investigate changes in magnetic resonance spectroscopy (MRS) of lentiform nucleus during the early stage of Parkinson's disease. METHODS: Twenty-five patients with idiopathic Parkinson disease with unilateral symptoms (IPDUS) and 25 healthy volunteers were enrolled in this study. MRS of the lentiform nucleus in each patient was taken and then concentrations of N-acetylaspartate (NAA), Creatine (Cr) and Choline (Cho) were calculated. RESULTS: Compared to that in the control, NAA/ (Cho+Cr) was significantly lower in the lentiform nucleus contralateral to symptoms and even that in the ipsilateral side in IPDUS patients (all P<0.05); while there was no difference between the two sides in the healthy volunteer (P>0.05). The ratio of NAA/(Cho+Cr) ipsilateral to the sympatomatic side of the patient was also lower than that of the control (P<0.05). CONCLUSIONS: There might be some changes with MRS on the lentiform nucleus during the early stage of idiopathic Parkinson's disease with unilateral symptom. MRS may be one of the reliable methods for early or even sub-clinical diagnosis.  相似文献   

2.
Manganese enhanced magnetic resonance imaging(MEMRI) is a novel neuroimaging technique first intro-duced by Lin et al. in 1997[1]. In this technique, bivalentmanganese ion (Mn2+) is used as a tracer for Ca2+, an im-portant substrate for neurotransmission. By monitoring thetransportation of Ca2+ between the cells and synapses,MEMRI can be used in vivo to trace neuronal tracts and tostudy brain functions dynamically. That Mn2+ can be usedas the tracer for Ca2+ is because it has two special…  相似文献   

3.
The biocompatibility and biodistribution of magnetic nanoparticles (MNPs) in vivo are essential to ensure their safely clinical application. We have studied these aspects with our 3-aminopropyltriethoxysilane-coated magnetic nanoparticles (APTS-MNPs) formulation, which can be used as magnetic induction hyperthermia media. Changes in tissue iron levels were analyzed after intraperitoneal injection of APTS-MNPs to ICR mice. Liver and kidney functions were tested. Heart, liver, spleen, lung, kidney, testis, and brain were sectioned for pathological analysis. Biodistribution of iron in various body tissues changed with time but greater fraction of the injected iron localized in the liver and spleen than in other tissues. Serum showed an increase in AST and LDH fol-lowing APTS-MNPs injection. Histological analyses of selected tissues showed no obvious abnormal changes. In conclusion, APTS-MNPs did not cause continuing changes in the liver and kidney function and thus can be safely used for in vivo application.  相似文献   

4.
为了研究从亮叶杨桐(Adinandra nitida Merr.ex Li)叶中制备山茶苷A对照品的方法,利用硅胶柱层析、重结晶和反相制备高效液相色谱对亮叶杨桐乙醇提取物进行分离纯化,以HPLC对山茶苷A进行纯度检查和含量测定,并通过各种波谱手段等对其进行结构确证.结果从亮叶杨桐叶分离、纯化出山茶苷A对照品,质量分数>99.0%.该方法制备出的山茶苷A对照品符合中药化学对照品的相关要求,可以作为亮叶杨桐药材和含亮叶杨桐成药质量控制,以及中药药效物质基础用的化学对照品.  相似文献   

5.
目的利用核磁共振弥散加权成像(DWI)联合核磁共振波谱分析(1H-MRS)及核磁共振磁敏感成像(SWI)研究HIE的MRI,探讨临床分度及预后关系。方法搜集28例经临床证实的新生儿HIE患者,行常规MRI、DWI、1H-MRS、SWI图,单体素PRESS(TE144ms)序列囊壁或囊内1H-MRS成像,测量N-乙酰天冬氨酸NAA、胆碱Cho、肌酸Cr、乳酸Lac、脂质Lip峰高,计算出Cho/Cr,Cho/NAA,NAA/Cr,并与随访结果进行比较。结果 (1)8例皮层及皮层下沿脑回迂曲点状条状高信号及或幕上幕下蛛网膜下腔少量出血;3例额叶深部白质两侧对称性点状高信号及或沿脑室壁条状高信号半局限性脑水肿;2例表现为基底节区,丘脑高信号伴内囊后肢地信号;1例脑室出血半病侧脑室扩大,皮层下囊状坏死,弥漫性脑水肿。(2)28例患者初次检查,DWI全部表现为对称性异常高信号;22例病变位于颞叶、额叶、顶叶;8例累及两侧基底节区。(3)5例NAA峰显著降低;8例Lac峰明显增高;GLx-a峰明显增高。(4)3例室管膜下斑点状低信号;6例脑室内条状低信号;1例皮层下点状低信号;5例侧脑室旁斑点状低信号。(5)随访2周,25例全部病变显示低信号,6个月和15个月持续性低信号。结论利用磁共振多模态技术能够判断超急性期,急性期的HIE,早期发现中重度HIE,指导临床判断预后。  相似文献   

6.
目的应用扩散张量与磁共振波谱技术,对急性脑卒中患者进行分析,探讨其反映患者病情变化的价值.方法取一侧脑卒中患者26例,健康志愿者30例.在常规扫描后再进行DTI,MRS扫描,采用NIHSS和BI评分评价患者功能,并定期复查.分析患者梗死病灶、大脑脚ADC值、FA值及MRS的代谢产物数值变化.结果 1)病灶FA值低于正常值,与NIHSS呈正相关,与BI呈负相关.脑干FA值减小,提示神经纤维出现华勒变性;2)病灶NAA下降,低于正常侧,P〈0.01;病灶侧Cr,Cho较正常侧改变不明显,P〉0.05;大脑脚NAA 1个月后降低.结论对脑卒中患者进行DTI与MRS扫描,能较早反映患者病情严重程度,还能判断预后,并指导临床康复治疗.  相似文献   

7.
To investigate the effect on central nervous transmission of toosendanin (TSN), a presynaptic blocker, rat striatum was perfusedin vivo with a TSN-containing artificial cerebrospinal fluid (ACSF) and the level of dopamine (DA) as well as related metabolites in the collected dialysates has been determined by a microbore HPLC with electrochemical detection (microbore HPLC-ECD). The results are as follows: ( i ) TSN induced a biphasic change of DA from its basal level;( ii ) the basal contents of two metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) increased in turn and stayed at a higher level than basal control for a long period. The basal level of 5-hydroxyindoleacetic acid (5-HIAA), a metabolite of 5-hydroxytryptamine(5-HT), had a change similar to that of HVA; ( iii ) after perfusion with TSN-containing ACSF, high K+-evoked DA release was inhibited. These results show that TSN does not selectively affect acetylcholine (ACh) release, but probably acts on a common mechanism responsible for transmitter release at different synapses by interfering with the proteins involved in fusian and resulting in diffusion of the vesicular contents into the cytoplasm and blockade of normal exocytosis.  相似文献   

8.
影响铁皮石斛原球茎生长的若干因素   总被引:22,自引:0,他引:22  
周根余  谢薇  程磊 《江西科学》1999,17(4):231-235
比较了不同无机盐浓度、不同碳源和不同pH 值对铁皮石斛原球茎生长的影响。实验结果表明:铁皮石斛原球茎生长较适宜的培养基为MS NAA1 mg·L- 1 w = 3% 蔗糖(pH为5 .0) 。  相似文献   

9.
The cellular localization and specific expression of TR3 mRNA in rat testis were investigated by the method of immuno- histochemistry andin situ hybridization. It was demonstrated that orphan receptor TR3 was expressed in a significant amount in rat testis and TR3 protein and mRNA were specifically localized in germ cells, suggesting that TR3 may have an important function in regulating rat germ cell development.  相似文献   

10.
A composite construct comprising of a bone mesenchymal stem cell (BMSC) sheet, plasmid DNA, encoding human bone morphogenic protein-2 (hBMP-2), and poly(lactide-co-glycolide)/hydroxyapatite (PLGA/HA) sponge was designed and employed in the restoration of rat calvarial defects. To improve gene transfection efficiency, a cationic chitosan derivative, N,N,N,-trimethyl chitosan chloride (TMC), was employed as the vector. The TMC/DNA complexes had a transfection efficiency of 13% in rat BMSCs, resulting in heterogeneous hBMP-2 expression in a 10-d culture period in vitro. In vivo culture of the composite constructs was performed by implantation into rat full-thickness calvarial defects, using constructs lacking pDNA-hBMP-2 or BMSC sheets as controls. Significantly higher heterogeneous expression of hBMP-2 was detected in vivo at 2 weeks for the cell sheet/DNA complex/scaffold constructs, compared with the constructs lacking pDNA-hBMP-2 or BMSC sheets. New bone formation was evident as early as 4 weeks in the experimental constructs. At 8 weeks, partial bridging of calvarial defects was observed in the experimental constructs, which was significantly better than the constructs lacking pDNA-hBMP-2 or BMSC sheets. Therefore, the combination of the PLGA/HA scaffold with BMSC sheets and gene therapy vectors is effective at enhancing bone formation.  相似文献   

11.
Hydrophilic ^99mTc-EC and nonlipophilic ^99mTc- MAMA'-BA complexes, owing to the existing of intact blood-brain barrier (BBB) in vivo, cannot cross from blood to brain. Previous studies showed that insulin is selectively transported by receptor-mediated transcytosis through the brain capillary endothelial wall that makes up the BBB. In this paper, based on the characteristic of the insulin receptor enriched in brain capillary, the complexes of hydrophilic ^99mTc-EC and nonlipophilic ^99mTc-MAMA'-BA are conjugated to insulin respectively. After purification, the radiochemical purity of ^99mTc-EC-insulin and ^99mTc-MAMA'-BA-insulin was 〉 90% and the stability in vitro was good. Expectation for the special formulation can be internalized and endocytosed into the capillary membrane by the vector-mediated brain delivery system, and transported ^99mTc-labeled conjugate through the BBB in vivo, thus enhancing brain uptake in mice. The biodistribution results of ^99mTc-EC-insulin and ^99mTc-MAMA'-BA-insulin in mice in- dicated that the brain uptake was higher than ^99mTc-EC and ^99mTc-MAMA'-BA to some extent. The ratios of brain uptake of ^99mTc-EC-insulin to ^99mTc-EC, ^99mTc-MAMA'-BA-insulin to ^99mTc-MAMA'-BA were 4-6 at 2 and 3 h post-injection respectively. In conclusion, the given results have illustrated a new way of brain uptake enhancing for nonlipophilic like complexes that have BBB delivery problems. It has a potential value for the ongoing development of ^99mTc-labeled radiopharmaceuticals for CNS receptors imaging.  相似文献   

12.
Inclusion of MARs in transgene cassettes enhances their expression and reduces position-effect variations in the transgenic host. Four new MARs (TM2, TM3, AM1 and AM2) were isolated from tobacco and Arabidopsis by PCR method. The nuclei isolated from suspensioncultured cells of rice were used to prepare nuclear matrix. With a characterized MAR (TM1) as a positive control, the Matrix-MAR interactions were tested by an in vitro binding assay to identify the DNA sequences as MARs and their binding strength to nuclear matrix in vitro was compared. The results showed that TM2 and TM3 had stronger binding strength than TM1. To determine the functions of the four new MARs in vivo, binary vectors pBI121 carrying a uidA GUS reporter gene were modified with direct repeat MARs inserted on both sides of the reporter gene cassette and were transferred into tobaccos via Agrobacterium-mediated transformation procedure. Quantitative GUS assays of the transgenic tobaccos showed that when flanking a GUS reporter gene TM1, TM2, TM3 and AM1 increased uidA GUS gene expression level approximately 1.5-fold, 5-fold, 1.35-fold, 1.3-fold respectively and AM2 has no effect on gene expression. TM2 was found to be a strong MAR that could effectively increase gene expression level and could be used as an effective enhancing element to construct high efficient expression vectors. In this note the relations among the sequence features, binding strength in vitro and function in vivo of the five MARs were analyzed, and the potential significance of TM2 in plant genetic engineering was discussed.  相似文献   

13.
14.
以初始诱导得到的山苍子[Litsea cubeba(Lour)Pers]幼苗进行继代培养试验。试验共设计3种培养基:改良MS+6-BA 0.5mg/L+NAA 0.2mg/L、改良MS+6-BA 0.8mg/L+NAA 0.2mg/L、改良MS+6-BA 1.0mg/L+NAA 0.2mg/L,2种切割方式,进行4代培养,研究生长调节剂、继代次数和切割方式对山苍子继代增殖的影响。结果以改良MS+6-BA 1.0mg/L+NAA 0.2mg/L培养基比较适宜山苍子的继代培养,当NAA浓度为0.2mg/L时,增殖率随6-BA浓度的增加而增大,愈伤组织逐渐减少,6-BA浓度为1.0mg/L时增殖率最高,苗木生长效果最好;继代到第4代时,山苍子增殖率明显高于前3代,增殖苗长势良好有活力;以2~3个丛芽块的接种方式接种效果优于单芽接种,增殖率可达到3.57,芽苗叶色浓绿效果最好。  相似文献   

15.
Traditional monolayer culture is still the common method used in hepatocarcinoma cell culturein vitro. For lack of the structure similar to thatin vivo, it is disadvantageous in the research of the relation between structure and function. We established a three-dimensional (3-D) culture model of human hepatocarcinoma cell (BEL-7402)in vitro by using microcarrier cytodex-3 in static condition. The results of SEM, TEM, enzyme activity and flow cytometry indicated that the cells were polygonal-shaped and arranged in multilayers. Intercellular space was 0.5–2.0 μm wide where lots of microvilli could be seen. Adjacent cells were connected with desmosomes and localized membrane projects. More than 90% of the cells were viable and maintained the consumption of glucose and the expression of EGF receptor. The intracellular ALT, AST and LDH-L activities were higher in 3-D culture than those of monolayer culture. Compared with monolayer culture, this 3-D culture with the structure similar to trabecular hepatocarcinomain vivo is much more suitable for the research of the interactions of cell-cell and cell-microenvironment, and might be useful in the investigation of the mechanisms of invasion, metastasis, and multicellular drug resistance of tumor cells.  相似文献   

16.
Using multi-color fluorescencein situ hybridization (FISH), we localized transferredbarnase-ps1 andpHctinG DNA sequences onto chromosomes of two transgenic rice plants, named Q12 and Q13, both of which were produced by micro-projectile bombardment. In both Q12 and Q13, each detected cell showed 2–3 signal spots on their chromosomes respectively. The signals of bothbarnase-ps1 andpHctinG were mostly detected in the adjacent chromosomal sites in which their signals were overlapped and could be recognized by the signal color on the metaphase chromosomes. Fiber FISH further demonstrated that the multiple copies in each of the two DNA sequences distributed adjacently on the DNA fiber in Q13. Combined with the results of Southern hybridization, the possible integration patterns in transgenic rice co-transformed by micro-projectile bombardment have been discussed.  相似文献   

17.
对黑节铁皮石斛的原球茎诱导、再分化以及腋芽萌发和生根进行了初步的研究,以期为黑节铁皮石斛的人工繁殖提供理论指导。采用植物组织培养和单因子试验的方法,获得了黑节铁皮石斛带芽茎段最佳的消毒方式为70%酒精处理30s后再用0.1%HgCl2处理20min。黑节铁皮石斛带芽茎段原球茎诱导的最佳培养基为MS+KT1mg/L+NAA0.1mg/L。黑节铁皮石斛带芽茎段原球茎再分化的最佳培养基为MS+KT2mg/L+NAA0.5mg/L。黑节铁皮石斛带芽茎段腋芽萌发的最佳培养基为MS+KT2mg/L+NAA0.5mg/L。黑节铁皮石斛带芽茎段生根的最佳培养基为1/2MS+NAA0.5mg/L。这些实验结果为黑节铁皮石斛试管苗的工厂化生产奠定了技术基础。  相似文献   

18.
α-萘乙酸(NAA)和吲哚-3-乙酸(IAA)的无保护流体室温烧光光谱相互重叠,但最大发射峰不同,本文据此建立了人工神经网络同时测定NAA和IAA的新方法。NAA和IAA的线性范围均为0.18~1.8mg/L;检出限分别为:0.14mg/L,0.13mg/L。NAA和IAA的烧光寿命分别为0.9697ms和0.4252ms。该法可甩于合成样和水样等实际样的测定,回收率在93%~109%之间。  相似文献   

19.
目的应用磁共振波谱成像(magnetic resonance spectroscopy,MRS)监测缺血性脑卒中卒中灶及脑干的温度变化.方法选取缺血性脑卒中患者15例,健康对照15例,分别于第1周及第8周行常规轴位T2WI,FLAIR及MRS扫描,测量卒中灶及脑干乙酰-天门冬氨酸(N-acety-L-asparticaca acid,NAA)化学位移,通过公式T=37+100(CSNAA-2.035)计算相应脑区温度,观察并对比分析数值的变化.结果患者卒中灶温度第1周高于第8周,差异具有统计学意义(P0.05);卒中灶温度第1周高于健康志愿者相应脑区,差异具有统计学意义(P0.05).结论 MRS能从分子水平研究缺血性脑卒中患者脑区温度变化,并有望用于评价临床疗效.  相似文献   

20.
To investigate the neuro-biological bases of introversion-extraversion personality traits, the concentration of four neuroehemieals (Cho, mI, α-Glx and NAA) in anterior eigulate gyrus between normal extroverts and introverts were examined using non-invasive ^1H MRS technique. Our study revealed that introverts have significantly higher level of α-Glx, Cho and mI in the anterior eingulate gyrus than extroverts. This result provides new evidence that the anterior eingulate gyrus is related to personality traits partly in support of Eysenek's supposition that introverts have higher arousal level than extroverts. Moreover, this result offers neuroehemieal data for psychobiological theories of personality.  相似文献   

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