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1.
【摘 要】 目的 探讨光动力疗法(PDT)对体外培养的铜绿假单胞杆菌的杀伤效应。方法 以多重耐药铜绿假单胞杆菌(P. aeruginosa)为对象,用457 nm和532 nm的激光作为光源,对不同浓度钌化合物孵育的细菌悬液进行光照,用菌落计数法观测PDT对铜绿假单胞杆菌的杀伤作用;同时观察了铜绿假单胞菌临床耐药菌与标准菌株对相同PDT作用的敏感性差异。结果 PDT处理组具有剂量-效应关系,在光照剂量相同的情况下,457 nm激光作为光源有更好的PDT杀伤效果;对多重耐药的铜绿假单胞菌,光动力同样有效,其作用甚至强于标准株。结论 钌化合物介导的光动力作用对体外培养的铜绿假单胞杆菌具有很强的杀伤作用,其效果和剂量关系密切。  相似文献   
2.
Four Ru(II) polypyridyl complexes, [Ru(bpy)2(7-NO2-dppz)]2+, [Ru(bpy)2(7-CH3-dppz)]2+, [Ru(phen)2(7-NO2-dppz)]2+, and [Ru(phen)2(7-CH3-dppz)]2+ (bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline), (7-Nitro-dppz = 7-Nitro dipyrido[3,2-a:2′-3′-c]phenazine, 7-CH3-dppz = 7-Methyl dipyrido[3,2-a:2′-3′-c]phenazine), have been synthesized and characterized by IR, UV, elemental analysis, 1H NMR, 13C-NMR, and mass spectroscopy. The DNA-binding properties of the four complexes were investigated by spectroscopic and viscosity measurements. The results suggest that all four complexes bind to DNA via an intercalative mode. Under irradiation at 365 nm, all four complexes were found to promote the photocleavage of plasmid pBR 322 DNA. Toxicological effects of the selected complexes were performed on industrially important yeasts (eukaryotic microorganisms).  相似文献   
3.
A novel tridentating ligand containing a single ionizable proton was designed for studying proton coupled electron transfer. The ligand was synthesized by derivatizing 2,2′-bipyridine at the 6-position with benzimidazole (bpy-bzimH), and it was used to prepare the compound [Ru(bpy-bzimH)2](PF6)2. Cyclic voltammetry was used to characterize the redox behavior in an aprotic (0.1 M TBAH-CH2Cl2) and protic (1:1 acetonitrile-water buffered solutions) solvent conditions where the latter was employed to characterize the pH-dependence of the Ru(III/II) couple. The redox potential as a function of pH was plotted and reveals a one-proton/one-electron transfer in two separate pH regions (1.39-2.58, and 5.92-7.97), while a two-proton/one-electron process was exhibited between 2.58 and 5.92.  相似文献   
4.
Computational chemical analysis of Ru(II)‐Pheox–catalyzed highly enantioselective intramolecular cyclopropanation reactions was performed using density functional theory (DFT). In this study, cyclopropane ring–fused γ‐lactones, which are 5.8 kcal/mol more stable than the corresponding minor enantiomer, are obtained as the major product. The results of the calculations suggest that the enantioselectivity of the Ru(II)‐Pheox–catalyzed intramolecular cyclopropanation reaction is affected by the energy differences between the starting structures 5l and 5i . The reaction pathway was found to be a stepwise mechanism that proceeds through the formation of a metallacyclobutane intermediate. This is the first example of a computational chemical analysis of enantioselective control in an intramolecular carbene‐transfer reaction using C1‐symmetric catalysts.  相似文献   
5.
A simple and sensitive electrochemiluminescence (ECL) method for the determination of etamsylate has been developed by coupling an electrochemical flow‐through cell with a tris(2,2'‐bipyridyl)ruthenium(II) (Ru(bpy)32+)–Nafion‐modified carbon electrode. It is based on the oxidized Ru(bpy)32+ on the electrode surface reacting with etamsylate and producing an excellent ECL signal. Under optimized experimental conditions, the proposed method allows the measurement of etamsylate over the range of 8–1000 ng/mL with a correlation coefficient of r = 0.9997 (n = 7) and a limit of detection of 1.57 ng/mL (3σ), the relative standard deviation (RSD) for 1000 ng/mL etamsylate (n = 7) is 0.96%. The immobilized Ru(bpy)32+ carbon paste electrode shows good electrochemical and photochemical stability. This method is rapid, simple, sensitive and has good reproducibility. It has been successfully applied to the determination of the studied etamsylate in pharmaceutical preparations with satisfactory results. The possible ECL reaction mechanism has also been discussed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
6.
Tetrapodal ligands H4L1 and H4L2 containing imidazole groups have been synthesized by the reaction of 1,10‐phenanthroline‐5,6‐dione with 1,2,4,5‐tetrakis[(4‐formylphenoxy)methyl]benzene and 1,2,4,5‐tetrakis[(3‐formylphenoxy)methyl]benzene, respectively, in presence of NH4OAc. Two star‐shaped complexes [{Ru(bpy)2}44‐H4L1)](PF6)8 and [{Ru(bpy)2}44‐H4L2)](PF6)8 (bpy = 2,2′‐bipyridine) have been prepared by refluxing Ru(bpy)2Cl2·2H2O and each ligand in ethylene glycol. The deprotonated complexes [{Ru(bpy)2}44‐L1)](PF6)4 and [{Ru(bpy)2}44‐L2)](PF6)4 have been obtained by the reaction of sodium methoxide with [{Ru(bpy)2}44‐H4L1)](PF6)8 and [{Ru(bpy)2}44‐H4L2)](PF6)8, respectively, in methanol. The pH effects on the UV–vis light absorption and emission spectra of both complexes have been studied, and ground‐ and excited‐state ionization constants of both complexes have been derived. The photophysical properties of both complexes are strongly dependent on the solution pH. They act as proton‐induced off–on–off luminescent sensors through two successive deprotonation processes of imidazole groups, with a maximum on–off ratio of 8 in buffer solution at room temperature. Theoretical calculations for the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LOMO) orbitals of bridging ligand are also presented for plausible explanations of the fluorescence changes. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
7.
Here we describe the efficient high yield atmospheric pressure microwave-assisted synthesis for seven distinct RuII coordination complexes relevant to solar energy conversion schemes and dye sensitized solar cells. In all instances, the reaction times have been markedly shortened, concomitant with higher yields with little or no need for subsequent purification and several multi-step reactions proceeded flawlessly in a single pot. Importantly, we observed no evidence for the decarboxylation of the essential metal oxide surface-anchoring 4,4′-diethylester-2,2′-bipyridine or 4,4′-dicarboxy-2,2′-bipyridine ligands as long as open reaction vessel conditions were utilized; these functionalities are not tolerant to sealed microwave reaction (superheated solvent/pressurized) conditions. The combined results suggest that microwave-assisted chemistry is indeed a valuable tool as far as RuII coordination chemistry is concerned and can likely be applied in the combinatorial pursuit of new dyes bearing sensitive functionalities.  相似文献   
8.
目的:探讨保留灌肠清胰汤联合内镜逆行胰胆管造影术(endoscopic retrograde pancreatic cholangiography,ERCP)治疗急性胆源性胰腺炎的临床疗效及作用机制。方法:选择2015年1月~2017年12月我院收治的97例胆源性胰腺炎患者为研究对象,根据治疗方法不同,将其分为对照组(ERCP组,46例)及观察组(保留灌肠清胰汤联合ERCP组,53例)。观察和比较两组的中医临床疗效,治疗前后7天的肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)、C反应蛋白(c-reactive protein,CRP)、白细胞介素-6(Interleukins-6,IL-6)、白细胞介素-8(Interleukin-8,IL-8)、白细胞介素-10(Interleukin-10,IL-10)水平及治疗前、治疗后12 h、24 h、3 d的血清淀粉酶水平的变化,腹痛缓解时间、平均住院时间、平均住院费用。结果:治疗后,观察组的痊愈、显效比例明显高于对照组(P0.05)。两组治疗后的血清TNF-α、CRP、IL-6、IL-8、IL-10水平均显著低于治疗前,且观察组的血清TNF-α、CRP、IL-6、IL-8水平均明显低于对照组(P均0.05);两组的平均住院费用对比差异无统计学意义(P0.05);观察组的腹痛缓解时间、平均住院时间明显低于对照组(P0.05)。与治疗前相比,两组治疗后12 h、24 h、3 d时的血清淀粉酶水平均显著降低,且观察组治疗后12 h、24 h时的血清淀粉酶水平均明显低于对照组(P均0.05)。结论:保留灌肠清胰汤联合ERCP治疗可显著提高急性胆源性胰腺炎的治疗痊愈率及有效率,其作用机制可能与降低患者血清TNF-α、CRP、IL-6、IL-8及淀粉酶水平有关。  相似文献   
9.
A sensitive electrochemiluminescence (ECL) detection of etimicin at Tris(2,2′‐bipyridyl)ruthenium(II) [Ru(bpy)32+]–Nafion modified carbon paste electrodes was developed. The immobilized Ru(bpy)32+ shows good electrochemical and photochemical activities. Electrochemical and electrochemiluminescence characterizations of the modified carbon electrodes were made by means of cyclic voltammetry and electrochemical impendence spectroscopy. The modified electrode showed an electrocatalytic response to the oxidation of etimicin, producing a sensitized ECL signal. The ECL sensor showed a linear response to etimicin in the range of 8.0–160.0 ng mL?1 with a detection limit of 6.7 ng mL?1. This method for etimicin determination possessed good sensitivity and reproducibility with a coefficient of variation of 5.1% (n = 7) at 100 ng mL?1. The ECL sensor showed good selectivity and long‐term stability. Its surface could be renewed quickly and reproducibly by a simple polish step. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
10.
Shi S  Yao TM  Geng XT  Jiang LF  Liu J  Yang QY  Ji LN 《Chirality》2009,21(2):276-283
New chiral Ru(II) complexes delta and lambda-[Ru(bpy)(2)(pyip)](PF(6))(2) [(bpy = 2,2'-bipyridine; pyip = (2-(1-pyrenyl)-1H-imidazo[4,5-f] [1,10]phenanthroline] were synthesized and characterized by elemental analysis, (1)H NMR, ESI-MS, IR, and CD spectra. Their DNA-binding properties were studied by means of UV-vis, emission spectra, CD spectra and viscosity measurements. A subtle but detectable difference was observed in the interaction of both enantiomer with CT-DNA. Spectroscopy experiments indicated that each of these complexes could interact with the DNA. The DNA-binding of the Delta-enantiomer was stronger than that of Lambda-enantiomer. DNA-viscosity experiments provided evidence that both Delta- and Lambda-[Ru(bpy)(2)(pyip)](PF(6))(2) bound to DNA by intercalation. At the same time, the DNA-photocleavage properties of the complexes were investigated too. Under irradiation with UV light, Ru(II) complexes showed different efficiency of cleaving DNA.  相似文献   
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