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101.
A. Urbano C. Babiloni P. Onorati F. Carducci A. Ambrosini L. Fattorini F. Babiloni 《The European journal of neuroscience》1998,10(2):765-770
We modelled the responses of human primary sensorimotor areas and supplementary motor area to simple, self-initiated unilateral and simultaneous bilateral middle finger movements using a novel high-resolution electroencephalography technology. The results support the view that these cortical motor areas are involved in parallel and present similar activity in the preparation, initiation, and execution of the contralateral and bilateral movements. Furthermore, the left primary sensorimotor area (dominant hemisphere) appears to be activated more than the right primary sensorimotor area during the preparation and performance of the ipsilateral movements. 相似文献
102.
G. V. Peersman F. L. Van de Vyver J. E. Lohman U. Lübke J. Gheuens E. Bellon A. Connelly J. J. Martin 《Acta neuropathologica》1988,76(6):628-632
Summary Chronic recurrent experimental allergic encephalomyelitis was induced in a strain 13 guinea pig by inoculation of isologous spinal cord homogenate. The spinal cord was obtained after perfusion with 4% paraformaldehyde and examined with nuclear magnetic resonance (NMR) imaging. Proton NMR spin echo images (repetition time: 3 s; echo times: 20 and 60 ms) were obtained from intact, isolated spinal cord in a 4.7 Tesla, 50 mm bore magnet. The slice thickness of the images was 380 m and the inplane resolution was 40×40 m. The images showed superficial areas of low signal intensity in the lateroventral regions of the white matter, in some instances with a seam of higher signal intensity. Neuropathologically, these abnormalities corresponded exactly to areas of demyelination. Control images did not show these abnormalities. The present high resolution imaging allowed a correlation between demyelination and abnormal NMR signals in a small laboratory animal with an inflammatory demyelinating disease.Supported by the Belgian Foundation of Medical Scientific Research (FGWO, grant 3.0096.86 and grant 3.0019.86), by the Institute for the promotion of Scientific Research in Industry and Agriculture (IWONL) and by the Scientic Research Planning Office of the Belgian Government (DPWB), contract no. 87/92-120 相似文献
103.
Possible site of bronchodilation due to inhaled procaterol aerosol in asthmatic patients 总被引:2,自引:0,他引:2
O. Taguchi W. Hida H. Nogami H. Inoue T. Takishima 《European journal of clinical pharmacology》1988,34(5):433-437
Summary We studied the effective site of an inhaled aerosol of procaterol, a 2-selective adrenergic bronchodilator, in 8 asthmatic patients whose basal lung functions are almost within the normal range in both slow vital capacity (VC) and forced expiratory volume in one second (FEV1.0), and are free from asthmatic attack. In patients who had received procaterol 30 min after inhalation of aerosol, there was no significant change in VC, although FEV1.0, maximal expiratory flow at 50% VC
, maximal expiratory flow at 25% VC
and maximal expiratory flow at 30% VC of partial maximal expiratory flow volume curve
improved significantly. On the other hand, in those who had received placebo, none of the parameters changed. Furthermore, Rl decreased and C0.5 increased significantly during the first 5 min after inhalation of procaterol aerosol. After an interval of 5 min, Rl did not change any further, while C0.5 continued to improve until 30 min after inhalation of procaterol. These results suggest that procaterol may first dilate the large airway and then may gradually dilate the small airway in bronchial asthma. 相似文献
104.
The solid-state nuclear magnetic resonance (NMR) technique of carbon-13 cross-polarization/magic angle spinning (CP/MAS) has been successfully used to obtain high-resolution spectra of whole-thickness, hairy rat skin and to characterize the influence of hydration on the efficiency of cross-polarization and the proton spin-lattice relaxation time in the rotating frame (T1H). Spectra obtained with hydrated samples, which were obtained with 50% more accumulations, had comparable signal-to-noise ratio relative to spectra obtained with dried skin, indicating a disordering effect with the presence of water. The integrated area of spectra of low-shifted peaks rose more rapidly with increasing contact time relative to the high-shifted peaks for both hydrated and dried skin. In addition, the carbonyl intensity of the hydrated skin relative to dried skin reached a maximum at shorter times, reflecting an efficient relaxation mechanism of the protons. The shift of the peak maximum to shorter mixing times quantitatively reflects the interaction of the protons of water with the carbonyl moiety. 相似文献
105.
目的:探讨人前病毒整合位点1(PIM1)诱导细胞衰老的分子机制。方法:构建过表达PIM1的2BS细胞系,通过Western印迹法和衰老相关β-半乳糖苷酶染色实验测定过表达PIM1是否诱导细胞衰老。免疫沉淀联合质谱分析测定PIM1是否能有效免疫沉淀核异质核糖核蛋白U(hnRNPU)蛋白。运用Real-timePCR和Western印迹法测定PIM1是否影响hnRNPUmRNA和蛋白表达水平。构建同时过表达PIM1和hnRNPU的2BS细胞系,运用Western印迹法和衰老相关β-半乳糖苷酶染色实验检测hnNRPU过表达对PIM1诱导的细胞衰老的影响。结果:与空载对照组相比,过表达PIM1组中衰老信号通路关键基因p53、p21和p16的表达显著增加(p53,t=4.36,P<0.05;p21,t=3.814,P<0.05;p16,t=4.72,P<0.01),衰老细胞的比例增加(t=6.831,P<0.01)。免疫沉淀联合质谱分析结果显示PIM1能有效免疫沉淀hnRNPU蛋白。PIM1过表达对hnRNPU的mRNA表达水平没有影响(t=0.295,P=0.783),但是能抑制hnRNPU蛋白的表达(t=33.85,P<0.001)。与只过表达PIM1细胞相比,同时过表达PIM1和hnRNPU细胞,衰老信号通路关键基因p53、p21和p16的表达下降(p53,t=15.317,P<0.001;p21,t=8.012,P<0.01;p16,t=14.08,P<0.001),衰老细胞的比例降低(t=10.38,P<0.01)。结论:hnRNPU过表达抑制PIM1诱导的细胞衰老。 相似文献
106.
巨噬细胞是先天免疫系统的主要细胞,具有可塑性和异质性,在机体的免疫应答、组织稳态、重塑等多方面发挥重要功能。根据功能极性可分为M1(促炎)和M2(抗炎)2个亚型。M1/M2巨噬细胞在响应局部微环境的刺激反应过程中,通过改变其功能极化,获得特定的功能表型并分泌不同的细胞因子。巨噬细胞通过改变代谢重编程以适应其功能变化。M2巨噬细胞以氧化磷酸化和脂肪酸为能量代谢的主要方式,而M1巨噬细胞为无氧糖酵解。目前研究发现在心血管疾病中,巨噬细胞可能通过其功能极性变化引起巨噬细胞激活、组织浸润、释放促炎性细胞因子而参与心血管疾病的发生。本文对巨噬细胞功能极化、代谢重编程在心血管疾病中的作用进行综述。 相似文献
107.
目的 探讨右美托咪定调控核因子E2相关因子2(Nrf2)/血红素加氧酶1(HO-1)通路对过氧化氢(H2O2)诱导心肌细胞氧化应激损伤的作用。方法 体外培养大鼠H9C2心肌细胞,设置对照组、H2O2组、1μmol右美托咪定+H2O2组、5μmol右美托咪定+H2O2组、10μmol右美托咪定+H2O2组。CCK-8法检测各组H9C2细胞增殖情况;酶联免疫吸附试验(ELISA)检测各组H9C2细胞丙二醛(MDA)、超氧化物歧化酶(SOD)水平;实时荧光定量聚合酶链反应(q RT-PCR)检测各组H9C2细胞Nrf2、HO-1 mRNA相对表达量;Western blotting检测各组H9C2细胞Nrf2、HO-1蛋白相对表达量。结果 与对照组比较,H2O2组H9C2细胞存活率、SOD水平、Nrf2、HO-1 mRNA及蛋白相对... 相似文献
108.
JOOP KONSTEN COR G.M.I. BAETEN KAREL DEN DULK FRANK SPAANS† 《Pacing and clinical electrophysiology : PACE》1992,15(5):825-830
Electromagnetic fields and myopotentials from skeletal muscle may interfere with the function of a cardiac pacemaker. A 65-year-old woman with a unipolar DDD cardiac pacemaker underwent dynamic graciloplasty (transposition of the gracilis muscle around the anal canal and subsequent implantation of a bipolar pulse generator to stimulate the gracilis muscle), for the treatment of fecal incontinence. This gracilis pulse generator is turned "off" with an external magnet to allow defecation. Appropriate functioning of these two pulse generators (the cardiac pacemaker and the gracilis pulse generator) was tested during implantation of the gracilis pulse generator and afterwards. It was demonstrated that the combination could be used safely in this patient. 相似文献
109.
Ou Y Enarson P Rattner JB Barr SG Fritzler MJ 《Clinical and experimental immunology》2004,136(2):379-387
We studied the autoantigen targets of 75 human sera that had antibodies to the nuclear envelope (NE) as identified by indirect immunofluorescence (IIF) on HEp‐2 cells. Several different IIF staining patterns could be identified when antibodies to different components of the nuclear membrane (NM) and nuclear pore complexes (NuPC) were identified: a smooth membrane pattern characteristic of antibodies to nuclear lamins, a punctate pattern typical of antibodies to the nuclear pore complex and more complex patterns that included antibodies to nuclear and cytoplasmic organelles. Western immunoblotting of isolated nuclear and NE proteins and immunoprecipitation of radiolabelled recombinant proteins prepared by using the full‐length cDNAs of the Translocated promoter region (Tpr), gp210 and p62 were used to identify specific autoantibody targets. Fifty‐two of the 75 (70%) sera bound to Tpr, 25 (33%) bound to lamins A, B or C, 15 (20%) reacted with gp210 and none reacted with p62. Sixteen (21%) did not react with any of the NE components tested in our assays. The clinical features of 37 patients with anti‐NE showed that there were 34 females and three males with an age range of 16–88 years (mean 59 years). The most frequent clinical diagnosis (9/37 = 24%) was autoimmune liver disease (ALD; two with primary biliary cirrhosis), followed by seven (19%) with systemic lupus erythematosus (SLE), four (11%) with a motor and/or sensory neuropathy, three (8%) with anti‐phospholipid syndrome (APS), two with systemic sclerosis (SSc), two with Sjögren's syndrome (SjS), and others with a variety of diagnoses. This report indicates that Tpr, a component of the NuPC, is a common target of human autoantibodies that react with the NE. 相似文献
110.
应用显微分光光度计测定15例鼻咽癌19处癌旁病变的上皮细胞核DNA含量并与浸润癌相比较。中、重度异型增生上皮细胞核DI及超过2.5c细胞的百分数处于单纯增生+轻度异型增生与浸润癌之间,3组DI及超过2.5c细胞的百分数差异显著。中、重度异型增生以非整倍体为主,其细胞核DNA含量组方图相似于浸润癌。从细胞核DNA含量角度来看,中、重度异型增生是重要的癌前病变。 相似文献