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TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu
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作者 Jingrong LU Jiangcun WEI +3 位作者 Xiumei MA Bing QING Meiyan QIU Wen ZHONG 《Medicinal Plant》 2024年第3期35-38,共4页
[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopte... [Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources. 展开更多
关键词 Chuanlianzhu THIN-LAYER chromatography (TLC) Extraction process Rubiadin-1-methyl ETHER Content determination
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Syntheses and Crystal Structures of Methyl 2-(4,5-Dibromo-1-methylpyrrole-2-carbonylamino)-3-phenylpropanoate and 4,5-Dibromo-1-methyl-2- trichloroacetylpyrrole
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作者 ZENG Xiang-Chao GU Jian XU Shi-Hai LIU Po-Run 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期153-158,共6页
4,5-Dibromo-1-methyl-2-trichloroacetylpyrrole Ⅰ, prepared by the reaction of 1-methyl-2-trichloroacetylpyrrole with Br2 in 98.6 % yield, was condensed with methyl L-2-amino-3- phenylpropanoate to afford methyl 2-(4,... 4,5-Dibromo-1-methyl-2-trichloroacetylpyrrole Ⅰ, prepared by the reaction of 1-methyl-2-trichloroacetylpyrrole with Br2 in 98.6 % yield, was condensed with methyl L-2-amino-3- phenylpropanoate to afford methyl 2-(4,5-dibromo-1-methylpyrrole-2-carboxmido)-3-phenylpropanoate Ⅱ in 90.8% yield. Crystal data for Ⅰ: monoclinic system, space group P21/c with a = 8.595(3), b = 10.900(4), c = 12.321(5) ,A°,β = 92.292(7)°, V = 1153.4(8)A°^3, Dc = 2.213 g/cm^3, F(000) = 728, CTH4Br2Cl3NO, Mr = 384.28, λ = 0.71073 A°, μ(MoKa) = 7.688 mm^-1, Z = 4, R = 0.0338 and wR2 = 0.0840 for 1963 observed reflections with I 〉 2a(I). Crystal data for Ⅱ: monoclinic system, space group P21 with a = 4.886(2), b = 15.921(8), c = 11.635(6) A°,β = 101.803(9)°, V = 885.9(7) A°^3, Dc = 1.665 g/cm^3, F(000) = 440, C16H16Br2N2O3, Mr = 444.13, λ = 0.71073 A°, μ(MoKa) = 4.590 mm^-1, Z = 2, R = 0.0335 and wR2 = 0.0837 for 3191 observed reflections with I 〉 2σ(I). The crystal structure reveals that compound Ⅱ forms the one-dimensional chain structure via the intermolecular hydrogen bonds of N(2)-H…O(1). 展开更多
关键词 methyl 2-(4 5-dibromo-1-methylpyrrole-2-carbonylamino)-3-phenylpropanoate synthesis crystal structure 4 5-dibromo-1-methyl-2-trichloroacetylpyrrole
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Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson’s disease 被引量:2
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作者 Wenbin Tu Furong Xu Guoguang Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第5期482-485,共4页
BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does ... BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does not exist. In addition, there are no reports of analysis of differential protein expression. OBJECTIVE: To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson's disease. DESIGN: Randomized controlled animal study. SETTING: Department of Neurology, the First Affiliated Hospital, Chongqing Medical University. MATERIALS: Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25 g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system (ChemiDoc XRS) by Bio-Rad, USA; and Voyager DE-PROMALD1-TOF-MS mass spectroscopy analyzer by AB1 Company, USA. METHODS: This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were received a subcutaneous injection of MPTP (25 mg&g), twice a week, for five successive weeks, to establish a chronic Parkinson's disease model. Mice in the control group received the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra. MAIN OUTCOME MEASURES: (1) 2-ED handbook (Bio-Rad Company) was referenced for two-dimensional electrophoresis, (2) PDQUEST8,0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. (3) Peptide mass finger print map and data were retrieved on http://www.prospector.ucsf.edu to compare differential substantia nigral protein expression in the two groups. RESULTS: Two-dimensional gel electrophoresis of substantia nigra tissue indicated that there were 33 differential protein expressions between the two groups. Three new proteins were evaluated, including α -enolase, which exhibited regulated expression, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. CONCLUSION: There are three proteins that exhibit differential expression in the substantia nigra- α -enolase, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. 展开更多
关键词 Parkinson's disease 1-methyl-4-phenyl-l 2 3 6-tetrahydropyridine mice substantia nigra proteomics
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1-methyl-4-phenylpyridinium ion induces endoplasmic reticulum stress through glycogen synthase kinase-3 beta activation in PC12 cells 被引量:1
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作者 Shengdong Wang Fucheng Luo Yan Chen Lei Qi Jie Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第11期805-810,共6页
1-methyl-4-phenylpyridinium ion (MPP^+) induces endoplasmic reticulum stress and activates caspase-12 in PC12 cells, leading to neuronal apoptosis. However, the underlying molecular mechanism remains unknown. The p... 1-methyl-4-phenylpyridinium ion (MPP^+) induces endoplasmic reticulum stress and activates caspase-12 in PC12 cells, leading to neuronal apoptosis. However, the underlying molecular mechanism remains unknown. The present study investigated the regulatory effects of nerve growth factor (Akt activator) and lithium chloride (glycogen synthase kinase-3β inhibitor) on the endoplasmic reticulum stress signaling pathway. The results revealed that MPP+ induced expression of Bip and C/EBP homologous protein. The upregulation of Bip and C/EBP homologous protein, as well as the decreased pro-caspase-12 level induced by MPP^+ were inhibited by pretreatment of the nerve growth factor or lithium chloride. These results suggest that the phosphatidylinositol 3 kinase-Aktglycogen synthase kinase-3β pathway is involved in MPP-induced endoplasmic reticulum stress. 展开更多
关键词 Parkinson's disease 1-methyl-4-phenylpyridinium ion endoplasmic reticulum stress glycogen synthase kinase-3β
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Minocycline protects the apoptosis of PC12 cells induced by 1-methyl-4-phenylpyridinium 被引量:1
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作者 Wei SHEN Shenggang SUN Xuebing CAO 《Journal of Nanjing Medical University》 2005年第5期247-250,共4页
Objective: To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP^+ . Methods: Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP^+... Objective: To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP^+ . Methods: Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP^+ were added into the culture medium of PC12 cells, and using MTr to assay the cell viability and metabolic state; The cells apoptosis was assayed by electrophoresis method and using flow cytometry FACS to assay the apoptosis ratio. Results: Added the MPP^+ to get the concentration of 10μmol/L, the cellular parkinsonism model of apoptosis had been prepared. The pre-treatment of MC ( 100/μmol/L) could significantly increase the PC12 cell viability. The apoptosis ratio of MC+MPP^+ group was significantly lower than that of MPP^+ group, but was still significantly higher than that of control group. Conclusion: MC may protect the cell apoptosis induced by MPP^+ to some extent. 展开更多
关键词 MINOCYCLINE PC12 cell apoptosis parkinson disease 1-methyl-4-mhenylpyridinium
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Neuroprotective effect of Eleutheroside B on 1-methyl-4-phenylpyridinium ion-induced apoptosis in PC12 cells
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作者 Fang Lu Yang Dong +4 位作者 Laijun Deng Shumin Liu Shihui Zhou Lifeng An Bo Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第18期1375-1379,共5页
Apoptosis and viability of PC12 cells following 1-methyl-4-phenylpyridinium ion (MPP+)-induced injury were monitored by flow cytometry, following Annexin V-propidium iodide double labeling, and 3-(4,5-Dimethylthia... Apoptosis and viability of PC12 cells following 1-methyl-4-phenylpyridinium ion (MPP+)-induced injury were monitored by flow cytometry, following Annexin V-propidium iodide double labeling, and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, respectively. The release of lactate dehydrogenase, superoxide dismutase activity and levels of malondialdehyde were determined by UV spectrophotometry. The changes in mitochondrial membrane potential and the intracellular concentration of calcium were determined by flow cytometry, and the activity of caspase-3 was monitored by western blot. According to cell viability and apoptosis studies, MPP+-induced apoptosis in PC12 cells was inhibited in the presence of 10 tJg/mL of Eleutheroside B Our results indicate that the neuroprotective effect of Eleutheroside B, following MPP+-induced apoptosis in PC12 cells, involves increasing the anti-oxidative stress capacity of cells, maintaining the high-energy state of mitochondrial membrane potential, reducing intracellular calcium concentration and inhibiting caspase-3 activity. 展开更多
关键词 Eleutheroside B PC12 cells APOPTOSIS 1-methyl-4-phenylpyridinium ion mitochondria Parkinson's disease
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Establishing motor disorder mouse models of Parkinson disease Comparison of 6-hydroxydompamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine
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作者 Zhi hua Ren Jie Gao Yan Chen Zhen yu Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第10期611-616,共6页
At present, pathogenesis and mechanism of Parkinson disease (PD) are still unclear. Animal models of PD are essential tools in studies on etiology and therapy and should mimic the chronic pathological process, histo... At present, pathogenesis and mechanism of Parkinson disease (PD) are still unclear. Animal models of PD are essential tools in studies on etiology and therapy and should mimic the chronic pathological process, histological characteristics and motor behavior dysfunction. In recent years, transgenic mice have been widely utilized to study the mechanism of PD, and it has become imperative that a PD mouse model of motor behavioral dysfunction be established. OBJECTIVE: To compare the behavioral and histochemical characters of two neurotoxic mice model induced with 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenyl-1, 2, 3, 6 -tetrahydropyridine (MPTP), and a better method to mimic Parkinson disease will be found out. DESIGN: Parallel experiment. SETTING: Laboratory of Molecular Genetics, Department of Medical Genetics, Shanghai Jiao Tohg University. MATERIALS: Sixty 129Sv/C57BL6J male wild mice, SPF grade, 8 - 12 weeks old, weighing 20 - 25 g, were provided by Experimental Animal Center, Shanghai Jiao Tong University. All the surgery operation was performed according to the rules of Shanghai Jiaotong University Animal Committee. METHODS: The experiment was carried out in the Laboratory of Molecular Genetics (National Key Laboratory), Department of Medical Genetics, Shanghai Jiao Ttong University from March to August 2006. ①Thirty-two male mice were randomly divided into control group and drug treatment group with 16 mice in each group. Surgery was carried out and 6-OHDA was administrated to substantia nigra pars compacta (SNpc) and nigra-striatum pathway according to the different parameters with intoxication apparatus. Saline was injected to the other 16 mice according to the same paradigm. 1 mg/kg apomorphine was injected intraperitoneally 2 weeks later after surgery to induce the imbalanced rotation behavior for 40 minutes. ②Twenty-eight mice were randomly divided into 4 groups with 7 in each group, including low-dose, moderate-dose, high-dose groups and negative control group. Then, mice in the drug treatment group were injected intraperitoneally with 5, 10 and 15 mg/kg MPTP for 9 successive days. In addition, mice in the control group were injected with the same volume of saline for 9 days. Pole test and stride length test were utilized to detect coordinative behavioral dysfunction. Mice were sacrificed 20 days after MPTP treatment, and histochemical staining of tyrosine hydroxynase (TH) was used to observe the loss of dopaminergic neuron in SNpc. MAIN OUTCOME MEASURES: ① Success ratio of each model establishment method; ② inducible asymmetric cycle behavior test 2 weeks after 6-OHDA injection; ③behavioral dysfunction in pole test and stride length, morphological changes in brain tissue. RESULTS: Totally sixty mice were used in this experiment and 3 mice were excluded because of the hypersensitivity or the clumsy reaction in motor behavioral detection before MPTP treatment, therefore, data was analyzed with the rest 57 mice. ① Lethal ratio: Three out of 16 mice died in striatum injection group and 5 out of 16 mice died in nigro-striatal pathway group. No mouse died in MPTP treatment groups. ② Locomotor behavior: No dysfunction of locomotor was found in 6-OHDA treatment groups. However, several motor behavioral dysfunction were start to present at the 4th day of MPTP injection. ③ Asymmetric cycle behavior: No asymmetric cycle was induced successfully two weeks after 6-OHDA surgery. Mice show hypersensitive behavior 10 minutes after apomorphine injection, which lasted for about 20 minutes. ④ Pole test: From the 4^th day of MPTP treatment, mice started to display coordinate dysfunction, such as climbing down along the pole in spiral, moving slowly with hesitation. Some mice could not grab the pole and slide down along the pole at 4th day post injection. Comparing with 0 dose control group, all the threedrug treatment groups show significant different dysfunction from the 4th day to the 20th day post injection (P 〈 0.01). ⑤ stride length test: Mice's stride length decreased, when treated with MPTP, and the mice in the high dose group displayed obviously. ⑥ Dopaminergic neuron stained with TH in nigra pars compacta: The results indicated that administrated MPTP (from low dose to high dose) by intraperitoneal cause chronic lesions on the dopaminergic neuron in the SNpc. CONCLUSION: PD mice models induced with 6-OHDA show high mortality ratio and no asymmetric cycle was found after apomorphine injection. However, injection of MPTP intraperitoneally can simulate the chronic pathway of PD, typical histological changes are found and stable motor behavioral dysfunctions are displayed. 展开更多
关键词 Parkinson disease 6-HYDROXYDOPAMINE 1-methyl-4-phenyl-1 2 3 6-tetrahydropyridine motor behavioral dysfunction
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MADOPAR-INDUCED DYSKINESIA IN 1-METHYL-4-PHENYL-1,2,3,6-TETRAHYDROPYRIDINE (MPTP) HEMIPARKINSONIAN MONKEY MODEL
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作者 陈生弟 周孝达 +3 位作者 钱可久 徐德隆 唐琴梅 徐修蓉 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1991年第1期41-46,共6页
Infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into the right common carotid artery produced hemiparkinsonian syndrome on contralateral limbs in 5 rhesus monkeys. The hemiparkinsonian syndrome produce... Infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into the right common carotid artery produced hemiparkinsonian syndrome on contralateral limbs in 5 rhesus monkeys. The hemiparkinsonian syndrome produced responded to madopar medication and the circling motion changed from toward the MPTP-treated side to away from the MPTP-treated side. Long term use of madopar developed a peak-dose dyskinesia of the face and limbs at the contralateral side. The toxic effect of MPTP was confirmed biochemically by reduction of nigrostriatal DA and histologically by degeneration of nigral neurons on the MPTP-treated side. It is concluded that this hemiparkinsonian monkey model will be of value in the elucidation of the neural mechanism underlying L-DOPA or DA agonists induced dyskinesia in Parkinson’s disease and in the search for newer methods of treatment which would produce less dyskinesia. 展开更多
关键词 DYSKINESIA MADOPAR hemiparkinsonism rhesus MONKEY 1-methyl-4-phenyl-1 2 3 6-TETRAHYDROPYRIDINE (MPTP)
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THE EFFECTS OF DEPRENYL AND 1-METHYL-4-PHENYL-1, 2, 3, 6-TETRAHYDROPYRIDINE (MPTP) ON 2-DEOXYGLUCOSE UPTAKE IN THE MOUSE BRAIN
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作者 陈生弟 徐德隆 +1 位作者 周孝达 钱可久 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1992年第1期70-74,共5页
~3H-2-deoxyglucose (2-DG) autoradiographic technique was used to study the ef feets of a monoamine-oxidase-B (MAO-B) inhibitor deprenyl and the neurotoxin Ⅰ-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) on 2-D... ~3H-2-deoxyglucose (2-DG) autoradiographic technique was used to study the ef feets of a monoamine-oxidase-B (MAO-B) inhibitor deprenyl and the neurotoxin Ⅰ-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) on 2-DG uptake in the mouse brain. Following MPTP intoxication, 2-DG uptake was increased in the substantia nigra and lo(?)us ceruleus. At the same time, obvious abnormal behavior of the animals was induced. In the mice pretreated with deprenyl, 2-DG uptake was similar to that of control animal. Ab normal behavior. though present, was significantly milder than in mice given MPTP alone. It is concluded that MPTP interferes with the glucose metabolism in the substantia nigra and locus ceruleus and induces remarkable abnormal behavioral syndrome of mice. These deleterious effects can be blocked by pretreatment with deprenyl. 展开更多
关键词 ~3H-2-deoxyglucose autoradiography DEPRENYL 1-methyl-4-phenyl-1 2 3 6—tetrahydropyridine
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Dual-parameter Correlation Analysis of the Fluorescence Data of 1-Methyl-2-formyl-5-substituted Pyrrole(4-nitrophenyl)hydrazones
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作者 Roderick Hat Ying HE Xi Kui JIANG(Shanghai Institute of organic Chemistry,354 Feng-Lin Lu.Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期499-502,共4页
By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence ... By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence spectra have been measured. Correlation results show that the Delta E-em values are mainly affected by polar effects, but spin-delocalizatin effects also exist. 展开更多
关键词 fluorescence spectra correlation analysis dual-parameter equation spin-delocalization effect polar effect 1-methyl-2-formyl-5-Y-substituted pyrrole (4-nitrophenyl)hydrazones
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Synthesis, Characterization and X-ray Crystal Structure of 2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline Bromide
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作者 甘紫云 曹日晖 +1 位作者 马芹 郭亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第7期1035-1040,共6页
2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide(H-2-65) was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The re... 2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide(H-2-65) was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The results demonstrate that H-2-65 has more remarkable anticancer activities in vitro. The results of 1H NMR, 13 C NMR, DEPT, g COSY, g HSQC, g HMBC, MS, single-crystal X-ray diffraction and elemental analysis showed that the title compound crystallizes in the triclinic system, space group P1 with a = 9.545(5), b = 11.724(5), c = 11.839(6) , α = 77.530(6), β = 87.169(6), γ = 72.823(5)o, Z = 2, V = 1235.8(10)3, Dc = 1.294 g·cm-3, F(000) = 504, the final R = 0.0453, wR = 0.1262 and S = 1.044. 展开更多
关键词 2-benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide synthesis crystalstructure
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Prenatal and Postnatal Exposures to 1-Methyl-4-phenyl-1,2,3,6-tetra Hydropyridine (MPTP) Impaired Mouse Midbrain Dopamine System and May Produce a Predisposing and Inducing Model for Parkinson’s Disease
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作者 Gladson Muthian Jennifer King +3 位作者 Lemuel Dent Marquitta Smith Veronica Mackey Clivel Charlton 《Journal of Behavioral and Brain Science》 2012年第4期485-494,共10页
Dopamine cell bodies in the substantia nigra of the midbrain and with their terminals projecting to the neostriatum form the nigrostriatum and these dopamine neurons degenerate in Parkinson’s disease (PD). Based on m... Dopamine cell bodies in the substantia nigra of the midbrain and with their terminals projecting to the neostriatum form the nigrostriatum and these dopamine neurons degenerate in Parkinson’s disease (PD). Based on metabolic and func- tional specialization of the cell bodies versus the axon terminals, the level and disposition of dopamine, its metabolites and enzymes are different in both regions and are likely to be affected differently in PD. We examined changes in the midbrain dopamine system following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), to test the hypothesis that a predisposing/sensitization stage and a inducing/precipitating stage underlie PD. Pregnant mice were treated with a low dose of MPTP during gestation days 8 - 12 to model the predisposing/sensitization stage, by interrupting the fetal mid- brain dopamine system during its neurogenesis. For the inducing/precipitating stage, the 12-weeks offspring were ad- ministered MPTP. The prenatal-MPTP offspring appear normal, but midbrain dopamine, 3,4-di-hydroxy-phenyl-acetic- acid, 3-methoxytyramine, tyrosine-hydroxylase and L-aromatic-amino-acid-decarboxylase, were reduced by 49.6%, 48%, 54%, 20.9% and 25%. Postnatal-MPTP of 10, 20, 30 mg/kg administered to the prenatal-PBS vs prenatal-MPTP offspring reduced midbrain dopamine by 43.6%, 47.2%, 70.3% vs 85.4%, 89.1%, 95.2%;tyrosine-hydroxylase by 30%, 63%, 81% vs 30.7%, 70.4%, 91.4%;L-aromatic-amino-acid-decarboxylase by 0%, 2%, 40% vs 32%, 40%, 58%. The prenatal-MPTP may render the DA system sensitive by causing sub-threshold reduction of DA, its metabolites and en- zymes, enabling postnatal-MPTP to reduce dopamine above the 70% - 80% PD-inducing threshold. Thus, the study may produce a prenatal predisposing/sensitization and postnatal inducing/precipitation model of PD. It also indicates that some cases of PD may have a fetal basis, in which sub-threshold nigrostriatal impairments occur early in life and PD-symptoms are induced during aging by further insults to the dopaminergic system that would not cause PD symptoms in normal indi-viduals. 展开更多
关键词 Parkinson’s Disease MIDBRAIN 1-methyl-4-Phenyl-1 2 3 6-TETRAHYDROPYRIDINE (MPTP) Dopamine Tyrosine Hydroxylase L-aromatic Amino Acid Decarboxylase Sensitization Precipitation
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Crystal and Molecular Structure, and Spectral Characteristics of Sodium 3,5-Bis(Hydroxyimino)-1-Methyl-2,4,6-Trioxocyclohexanide
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作者 Olga Kovalchukova Nguyen Dinh Do +6 位作者 Adam Stash Vitaly Bel’sky Paul Strashnov Andrew Alafinov Oleg Volyansky Svetlana Strashnova Konstantin Kobrakov 《Crystal Structure Theory and Applications》 2012年第3期46-51,共6页
Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has bee... Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I. 展开更多
关键词 SODIUM 3 5-Bis(Hydroxyimino)-1-methyl-2 4 6-Trioxocyclohexanide CRYSTAL Structure IR SPECTRA Electronic Absorption SPECTRA Quantum Chemical Modeling
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Transfer kinetics of phenol between aqueous phase and N,N-di(1-methyl-heptyl) acetamide in kerosene 被引量:2
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作者 Zhu-xian, Y. Hui-fang, D. +1 位作者 Qi-hong, Z. Zu-ming, Z. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第2期19-23,共5页
The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of p... The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of phenol in aqueous phase and organic phase, the concentration of N503 in organic phase, the acidity of aqueous phase, the stirring speed and the temperature on the rates of forward and backward extraction of phenol have been examined. The regularity of extraction rate has been obtained. According to experimental results, the rates of both forward and backward extraction of phenol might be controlled by diffusion process. The diffusion step of phenol from aqueous phase to interface for forward extraction and from interface to aqueous phase for backward extraction might be the rate controlling steps. 展开更多
关键词 PHENOL transfer kinetics N N di(1 methyl heptyl) acetamide CLC number: X703 Document code: A Introduction
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Experimental and Theoretical Spectral(FT-IR,Raman,NMR,UV-Vis and NLO)Analysis of a Potential Anti-Tumor Drug:1-Methyl-6-Nitro-1H-Benzimidazole
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作者 Halil Oturak Neslihan Kaya Kιnaytürk Cagrι Cιrak 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第6期1963-1969,共7页
In the present work,the experimental and the theoretical spectroscopic properties of 1-Methyl-6-Nitro-1H-Benzimidazole were investigated.The FT-IR(400~4 000cm^(-1))and FT-Raman spectra(100~4 000cm^(-1))of 1-Methyl-6-N... In the present work,the experimental and the theoretical spectroscopic properties of 1-Methyl-6-Nitro-1H-Benzimidazole were investigated.The FT-IR(400~4 000cm^(-1))and FT-Raman spectra(100~4 000cm^(-1))of 1-Methyl-6-Nitro-1H-Benzimidazole in the solid phase were recorded.Also,experimental NMR and UV spectra of titled molecule were measured.To interpret the experimental data,geometric parameters,vibrational frequencies,NMR,UV spectra and NLO analysis of the optimized molecule were calculated using ab initio Hartree–Fock(HF)method and density functional theory(B3LYP)method with the 6-31++G(d,p)and 6-311++G(d,p)basis sets.Vibrational bands were assigned based on the potential energy distribution using the VEDA 4program.The theoretical results showed good agreement with the experimental values. 展开更多
关键词 光谱学 英文 摘要
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电容器用双向拉伸聚4-甲基-1-戊烯(BOPMP)薄膜开发与应用
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作者 储松潮 潘毓娴 +5 位作者 黄云锴 潘焱尧 石兆峰 汪威 唐兵 冯玲 《电力电容器与无功补偿》 2024年第1期41-48,共8页
聚4-甲基-1-戊烯(PMP)是一种具有等规结构的新型热塑性塑料,PMP为结晶性树脂,熔点在235℃~240℃之间,耐热性好,可在高温下使用,并具有卓越的电气绝缘和介电性能。与聚丙烯树脂相比,熔点高60℃,介电常数、介电损耗相近。随着我国电子工... 聚4-甲基-1-戊烯(PMP)是一种具有等规结构的新型热塑性塑料,PMP为结晶性树脂,熔点在235℃~240℃之间,耐热性好,可在高温下使用,并具有卓越的电气绝缘和介电性能。与聚丙烯树脂相比,熔点高60℃,介电常数、介电损耗相近。随着我国电子工业的发展,PMP的用量在近年来有大幅的增长。目前世界上只有日本三井化学株式会社生产,由于产量有限、售价较高,限制了PMP在国内的应用。为此本文尝试采用双向拉伸的方法,试制聚4-甲基-1-戊烯(BOPMP)薄膜,并加工成金属化膜,试制电容器,最后对电容器的性能进行相应测试评价。采用不同牌号原料生产BOPMP薄膜,其电压击穿强度差别较大,不同频率下的BOPMP薄膜电容器损耗角正切值、介电常数均与BOPP薄膜电容器接近,但其高温下的性能有待进一步验证。如何提升BOPMP薄膜电压击穿强度及其耐热性,开发出适宜于双向拉伸的PMP粒子原料,生产出高质量的BOPMP电容薄膜,将是未来重点研究的方向。 展开更多
关键词 金属化薄膜电容器 聚4-甲基1-戊烯 双向拉伸 BOPMP
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佛手多糖对1-甲基-4-苯基-吡啶离子诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用研究
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作者 陈进炫 龚舒 +3 位作者 刘天开 龚记熠 乙引 刘文华 《食品与发酵工业》 CAS CSCD 北大核心 2024年第8期17-23,共7页
该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s dis... 该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s disease,PD)细胞模型,实验分为对照组、MPP+模型组、佛手多糖组。采用噻唑蓝(methye thiazdye telrazlium,MTT)法检测细胞存活率,Hoechst33258染色法观察细胞形态,2′,7′-二氯荧光黄双乙酸盐荧光探针检测细胞活性氧(reactive oxygen species,ROS)水平,JC-1荧光探针法检测线粒体膜电位,蛋白免疫印迹(Western blot)检测磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、蛋白激酶B(protein kinase B,Akt)、磷酸化细胞外调节蛋白激酶(phosphorylated extracellular regulated protein kinases1/2,p-ERK1/2)和细胞色素c(cytochrome c,Cyt-c)蛋白表达水平。结果表明,佛手多糖的得率4.86%,纯度为44.46%,经过AB-8纯化后,纯度提高到60.81%;与对照组相比,模型组细胞的存活率显著降低,Hoechst33258染色下可见细胞破碎,细胞核皱缩,细胞内ROS显著增加,线粒体膜电位显著降低。与模型组相比,佛手多糖组的细胞存活率显著增加,细胞形态明显得到改善,ROS水平下降,线粒体膜电位升高。Western blot结果显示,佛手多糖能抑制MPP+引起的p-Akt和p-ERK1/2的降低,以及Cyt-c的上升。综上,佛手多糖对MPP+诱导SH-SY5Y细胞损伤具有保护作用,其机制可能是通过调节线粒体ROS的产生和Cyt-c的释放,进而维持线粒体稳态,激活Akt信号通路和ERK信号通路,抑制细胞的凋亡,从而起到保护作用。研究结果可为缓解帕金森病的发生发展提供理论依据,同时也能更好地开发和利用佛手资源。 展开更多
关键词 佛手多糖 提取纯化 MPP+ SH-SY5Y细胞 保护作用
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1-甲基-2,4,5-三硝基咪唑的微通道合成技术
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作者 廉鹏豹 张源 +4 位作者 谷玉龙 吴静静 赵芦奎 曹彩 王建龙 《火炸药学报》 EI CAS CSCD 北大核心 2024年第6期541-548,I0004,共9页
采用微通道式反应技术,分别以1-甲基-2,4-二硝基咪唑(2,4-MDNI)与硝硫混酸硝化反应、2,4,5-三硝基咪唑钾盐(2,4,5-TNIK)与硫酸二甲酯(DMS)甲基化反应,合成了1-甲基-2,4,5-三硝基咪唑(MTNI);采用傅里叶变换红外光谱(FT-IR)、核磁共振光谱... 采用微通道式反应技术,分别以1-甲基-2,4-二硝基咪唑(2,4-MDNI)与硝硫混酸硝化反应、2,4,5-三硝基咪唑钾盐(2,4,5-TNIK)与硫酸二甲酯(DMS)甲基化反应,合成了1-甲基-2,4,5-三硝基咪唑(MTNI);采用傅里叶变换红外光谱(FT-IR)、核磁共振光谱(NMR)、元素分析(EA)、熔点等表征了其结构。结果表明,采用微通道反应技术,基于2,4-MDNI硝化工艺的最优条件为:2,4-MDNI和发烟硝酸摩尔比为2∶3、发烟硝酸和20%发烟硫酸体积比为1∶2、在微通道反应器中停留时间为12min、反应器中反应液温度为75℃,得率和纯度分别为78.1%和99.2%。基于2,4,5-TNIK甲基化工艺的最优条件为:2,4,5-TNIK、DMS和K2CO3摩尔比为1∶2∶2、在微通道反应器中停留时间为20min、反应温度为70℃,得率和纯度分别为71.3%和99.4%。由此可得,微通道式反应工艺与常规釜式反应工艺相比,具有反应时间短、硝化试剂用量少、反应温度略有降低、得率略有提高的优点。 展开更多
关键词 有机化学 微通道式反应器 硝化反应 甲基化反应 1-甲基-2 4 5-三硝基咪唑 MTNI 2 4-MDNI
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1,1’-磺酰基双(2-甲基-1H-咪唑)对宽带隙钙钛矿太阳电池性能的影响
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作者 戴峣 王鹏阳 +1 位作者 赵颖 张晓丹 《太阳能学报》 EI CAS CSCD 北大核心 2024年第4期43-50,共8页
对倒置结构,带隙为1.68 eV的钙钛矿太阳电池光吸收层掺杂1,1’-磺酰基双(2-甲基-1H-咪唑),以改善钙钛矿薄膜质量,提高太阳电池性能。空间电荷限制电流(SCLC)测试结果表明,掺杂后的钙钛矿薄膜的缺陷密度明显降低;稳态光致发光光谱(PL)结... 对倒置结构,带隙为1.68 eV的钙钛矿太阳电池光吸收层掺杂1,1’-磺酰基双(2-甲基-1H-咪唑),以改善钙钛矿薄膜质量,提高太阳电池性能。空间电荷限制电流(SCLC)测试结果表明,掺杂后的钙钛矿薄膜的缺陷密度明显降低;稳态光致发光光谱(PL)结果表明,掺杂后的钙钛矿薄膜的非辐射复合被显著抑制;最终太阳电池的开路电压达到1.17 V,光电转换效率达到21.42%,在氮气环境下储存1000 h后,未封装的太阳电池仍能保持初始效率的96%,稳定性显著提高。 展开更多
关键词 钙钛矿太阳电池 晶体生长 宽带隙半导体 钝化 1 1’-磺酰基双(2-甲基-1H-咪唑)
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结直肠癌p53和DNA损伤调节基因1的表达及临床意义
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作者 张丽静 贾彦彦 +3 位作者 胡波 李晓慧 张倩倩 周长江 《实用肿瘤杂志》 CAS 2024年第2期149-154,共6页
目的 分析p53和DNA损伤调节基因1(p53 and DNA damage regulated gene 1,PDRG1)在结直肠癌中的表达及其临床意义。方法 检索癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中结直肠癌数据集,比较PDRG1 mRNA在结直肠癌组织和正常... 目的 分析p53和DNA损伤调节基因1(p53 and DNA damage regulated gene 1,PDRG1)在结直肠癌中的表达及其临床意义。方法 检索癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中结直肠癌数据集,比较PDRG1 mRNA在结直肠癌组织和正常结直肠组织中的表达差异,分析其表达与临床病理特征及预后的关系。DNA甲基化交互可视化数据库(DNA methylation interactive visualization database,DNMIVD)分析PDRG1基因甲基化与m RNA表达水平的关系。另选取本院2019年2月至2020年5月存档的102例结直肠癌组织及其癌旁正常结直肠组织石蜡标本进行验证,采用免疫组织化学法检测PDRG1蛋白的表达。结果 TCGA数据库分析发现,PDRG1 mRNA在结直肠癌组织(n=284)中的表达较正常结直肠组织(n=41)增高(P<0.01),且结直肠癌PDRG1 mRNA表达与拷贝数变异呈正相关(n=273;r=0.792,P<0.01)。DNMIVD分析显示,PDRG1启动子甲基化β值与基因表达水平呈负相关(r=-0.34,P<0.01)。TCGA数据库分析显示,结直肠癌患者(n=273)PDRG1 mRNA表达在肿瘤位置、TNM分期及远处转移方面比较,差异均具有统计学意义(均P<0.05);对245例结直肠癌患者进行Kaplan-Meier生存分析发现,PDRG1 mRNA高表达患者(以中位数为分界值,大于中位数为高表达)无瘤生存期较短(P=0.019)。免疫组织化学检测显示,结直肠癌组织中PDRG1蛋白表达阳性率高于正常结直肠癌组织[87.3%(89/102) vs32.4%(33/102),P<0.01]。结论 PDRG1在结直肠癌中高表达,且与肿瘤位置、远处转移和无瘤生存期有关,可能成为结直肠癌潜在的生物标志物。 展开更多
关键词 结直肠癌 p53和DNA损伤调节基因1 癌症基因组图谱 甲基化 预后 标志物
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