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排序方式: 共有323条查询结果,搜索用时 31 毫秒
241.
Anna Nowak Martyna Zagrska-Dziok Paula Ossowicz-Rupniewska Edyta Makuch Wiktoria Duchnik ukasz Kucharski Urszula Adamiak-Giera Piotr Prowans Norbert Czapla Piotr Bargiel Jan Petriczko Marta Markowska Adam Klimowicz 《Molecules (Basel, Switzerland)》2021,26(11)
Epilobium angustifolium L. is a popular and well-known medicinal plant. In this study, an attempt to evaluate the possibility of using this plant in preparations for the care and treatment of skin diseases was made. The antioxidant, antiaging and anti-inflammatory properties of ethanolic extracts from Epilobium angustifolium (FEE) were assessed. Qualitative and quantitative evaluation of extracts chemically composition was performed by gas chromatography with mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The total polyphenol content (TPC) of biologically active compounds, such as the total content of polyphenols (TPC), flavonoids (TFC), and assimilation pigments, as well as selected phenolic acids, was assessed. FEE was evaluated for their anti-inflammatory and antiaging properties, achieving 68% inhibition of lipoxygenase activity, 60% of collagenase and 49% of elastase. FEE also showed high antioxidant activity, reaching to 87% of free radical scavenging using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 59% using 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Additionally, in vitro penetration studies were performed using two vehicles, i.e., a hydrogel and an emulsion containing FEE. These studies showed that the active ingredients contained in FEE penetrate through human skin and accumulate in it. The obtained results indicate that E. angustifolium may be an interesting plant material to be applied as a component of cosmetic and dermatological preparations with antiaging and anti-inflammatory properties. 相似文献
242.
Urszula Rychlewska Beata Warżajtis Danica Cvetić Dušanka D. Radanović Dejan M. Gurešić Miloš I. Djuran 《Polyhedron》2007
The ability of Mn(II) ion to form two distinctly different complexes with 1,3-propanediaminetetraacetate (1,3-pdta) ligand has been demonstrated by performing X-ray analyses of their crystalline Mg(II) salts. The two types of Mn(II) complexes have been obtained by different synthetic routes and their crystals constitute, respectively, the solid solution of the composition [Mg(H2O)6][Mg0.5Mn0.5(1,3-pdta)] · 2H2O (1) and the ordered crystals of the composition [Mg(H2O)6][Mn(1,3-pdta)(H2O)] · 2H2O (2). In both, six- 1 and seven-coordinated 2 Mn(II) complexes the 1,3-pdta ligand acts as a hexadentate. As 2 makes the second example of the seven-coordinated 1,3-pdta complex with divalent transition metal ion, the other being the [Mg(H2O)6][Cd(1,3-pdta)(H2O)] · 2H2O (3) complex, the paper reports the results of X-ray investigations of both of these complexes at 130 K. 相似文献
243.
244.
Urszula Domańska Piotr Morawski Maria Piekarska 《The Journal of chemical thermodynamics》2008,40(4):710-717
The (solid + liquid) phase equilibria (SLE) of binary mixtures containing 1-octanol and fragrance raw materials based on cyclohexane were investigated. The systems {1-octanol (1) + cyclohexyl carboxylic acid (CCA), or cyclohexyl acetic acid (CAA), or cyclohexyl acetate (CA), or 2-cyclohexyl ethyl acetate (2CEA), or 2-cyclohexyl ethanol (2CE)(2)} have been measured by a dynamic method in wide range of temperatures from (220 to 320) K and ambient pressure. For all systems SLE diagrams were detected as eutectic mixtures with complete miscibility in the liquid phase. The experimental data were correlated by means of the Wilson and NRTL equations, utilizing parameters derived from the (solid + liquid) equilibrium. The root-mean-square deviations of the solubility temperatures for all calculated data are dependent upon the particular system and the particular equation used.Additionally, the SLE in binary mixture that contain {1-octanol (1) + CCA (2)} has been measured under very high pressures up to about 900 MPa at the temperature range from T = (303.15 to 353.15) K. The thermostatted apparatus for the measurements of transition pressures from the (liquid + solid) state was used. The freezing and melting temperatures at a constant composition increase monotonously with pressure. The high pressure experimental results obtained at isothermal conditions (p–x) were interpolated to more convenient T–x diagram. Data of the (pressure + temperature) composition relation at the high pressure (solid + liquid) phase equilibria was correlated by the polynomial based on the Yang model.The basic thermodynamic properties of pure substances viz. the melting point, enthalpy of fusion, enthalpy of solid–solid phase transition, and glass transition, have been determined by the differential scanning calorimetry (DSC). 相似文献
245.
Beata Michalkiewicz Joanna Sreńscek-Nazzal Piotr Tabero Barbara Grzmil Urszula Narkiewicz 《Chemical Papers》2008,62(1):106-113
The investigations of selective methane oxidation to formaldehyde over T-Nb2O5, the mixture of M-Nb2O5 and H-Nb2O5 as well as H-Nb2O5 were carried out. The tests were conducted under atmospheric pressure, in the temperature range 420–750°C, using oxygen as
the oxidizing agent. T-Nb2O5 samples were examined at the contact time 0.7–1.8 s (GHSV 2000–5143 h−1). Other polymorphic forms of niobium(V) oxide were examined at the contact time 0.9 s. Various polymorphic forms of Nb2O5 displayed various formaldehyde and carbon dioxide yield. Using H-Nb2O5 and M-Nb2O5 phases with a block type structure, made it possible to obtain higher formaldehyde selectivity (78 % at 0.9 s) as compared
to T-Nb2O5 (47 % at 0.9 s), a polymorphic form which does not have a block type structure. However, the highest space time yield of
formaldehyde (46 g per kg of catalyst per h) was obtained over T-Nb2O5 supported on SiO2.
Presented at the 34th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 21–25 May
2007. 相似文献
246.
MSc Daria B. Wojtala Sc.D. Urszula K. Komarnicka Sc.D. Agnieszka Kyzioł Dr. Sandra Kozieł BSc Magdalena Szmitka MSc Mateusz Słowikowski MSc Julia Kulczyńska Prof. Grażyna Stochel 《欧洲无机化学杂志》2023,26(33):e202300515
Two piano-stool ruthenium(II) complexes Ru(η6-p-cymene)Cl2PPh2CH2OH ( RuPOH ) and Ru(η6-p-cymene)Cl2P(p-OCH3Ph)2CH2OH ( RuMPOH ) and two half-sandwich iridium(III) complexes Ir(η 5-Cp*)Cl2PPh2CH2OH ( IrPOH ) and Ir(η 5-Cp*)Cl2P(p-OCH3Ph)2CH2OH ( IrMPOH ) have been studied in terms of potential anticancer activity on previously selected cell line (human lung adenocarcinoma). Based on experimental results obtained in monoculture in vitro model mechanistic considerations on the possible cellular modes of action have been carried out. ICP-MS analysis revealed the higher cellular uptake for less hydrophobic Ir(III) complexes in comparison to the corresponding Ru(II) compounds. Cytometric analysis showed a predominance of apoptosis over the other types of cell death for all complexes. The apoptotic pathway was confirmed by a decrease in mitochondrial membrane potential and the activation of caspases-3/9 for both Ru(II) and Ir(III) complexes. It was concluded that in the case of Ru(II) complexes the intense ROS generation is mainly responsible for the resulting cytotoxicity. The corresponding Ir(III) complexes trigger simultaneously at least three different cytotoxic pathways i. e., depletion of mitochondrial potential, activation of caspases-dependent apoptosis, and ROS-associated oxidation. Thus, it can be assumed that the final accumulation of toxic effects over time via parallel activation of different pathways results in the highest cytotoxicity in vitro exhibited by Ir(III) complexes when compared with Ru(II) complexes. 相似文献
247.
Cytotoxic and Antimicrobial Properties of Copper(II) Complexes of Pyridine and Benzimidazole Derivatives
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Urszula Kalinowska‐Lis Ilona Szabłowska‐Gadomska Katarzyna Lisowska Justyn Ochocki Maciej Małecki Aleksandra Felczak 《无机化学与普通化学杂志》2017,643(15):993-998
The cytotoxic and antimicrobial activity of a series of six copper(II) complexes with phosphate and hydroxymethyl derivatives of pyridine and benzimidazole were investigated. The complexes and the corresponding free ligands were tested against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Pseudomonas aeruginosa ATCC 15442, Escherichia coli ATCC 25922, Proteus hauseri ATCC 13315, and Candida albicans ATCC 10231. Among the tested copper(II) complexes, compounds 2 and 5 containing 1H‐benzimidazol‐2‐ylmethyl diethyl phosphate and 2‐(hydroxymethyl)benzimidazole as ligands, respectively, were most active and limited the growth of S. aureus, E. coli, and C. albicans by 30–60 % according to concentration and microorganism. The in vitro cytotoxic activity of the CuII complexes and free ligands towards cancerous B16 (murine melanoma) and non‐cancerous 10T1/2 (murine fibroblasts) cell lines was determined. The 10T1/2 cells were treated with the compounds at concentrations equal to IC50 values for B16 cells. In spite of the use of relatively high concentrations of the complexes, the viability of 10T1/2 cells was very high, ca. 80 % in some cases. Stability of the CuII complexes was evaluated in water solutions by UV/Vis spectroscopy. The copper(II) complex of 4‐(hydroxymethyl)pyridine was synthesized and identified. 相似文献
248.
A Functional Role for Aβ in Metal Homeostasis? N‐Truncation and High‐Affinity Copper Binding
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Mariusz Mital Nina E. Wezynfeld Tomasz Frączyk Magdalena Z. Wiloch Urszula E. Wawrzyniak Arkadiusz Bonna Carolin Tumpach Kevin J. Barnham Cathryn L. Haigh Wojciech Bal Simon C. Drew 《Angewandte Chemie (International ed. in English)》2015,54(36):10460-10464
Accumulation of the β‐amyloid (Aβ) peptide in extracellular senile plaques rich in copper and zinc is a defining pathological feature of Alzheimer′s disease (AD). The Aβ1–x (x=16/28/40/42) peptides have been the primary focus of CuII binding studies for more than 15 years; however, the N‐truncated Aβ4–42 peptide is a major Aβ isoform detected in both healthy and diseased brains, and it contains a novel N‐terminal FRH sequence. Proteins with His at the third position are known to bind CuII avidly, with conditional log K values at pH 7.4 in the range of 11.0–14.6, which is much higher than that determined for Aβ1–x peptides. By using Aβ4–16 as a model, it was demonstrated that its FRH sequence stoichiometrically binds CuII with a conditional Kd value of 3×10?14 M at pH 7.4, and that both Aβ4–16 and Aβ4–42 possess negligible redox activity. Combined with the predominance of Aβ4–42 in the brain, our results suggest a physiological role for this isoform in metal homeostasis within the central nervous system. 相似文献
249.
Summary. Various heteroaromatic N-oxides were efficiently deoxygenated to the corresponding bases under mild conditions using formamidinesulfinic
acid (thiourea S,S-dioxide).
Received March 24, 2000. Accepted April 18, 2000 相似文献
250.
Urszula Trych Magdalena Buniowska Sylwia Skpska Ireneusz Kapusta Krystian Marszaek 《Molecules (Basel, Switzerland)》2022,27(3)
Blackcurrant juice (Ribes nigrum L.) was subjected to supercritical carbon dioxide (SCCD) at 10, 30, and 60 MPa for 10 min at 45 °C, as well as thermally treated at 45 and 85 °C for 10 min to determine the stability, antioxidant capacity (AC), and bioaccessibility (BAc) of vitamin C, total anthocyanins, and their individual monomers. An in vitro gastrointestinal digestion model completed with dialysis was used to assess BAc. The use of SCCD at each of the pressures applied improved the stability of vitamin C, total anthocyanins, and AC before in vitro digestion. As a result of digestion, the total content of vitamin C, anthocyanins, and AC decreased. The highest BAc of vitamin C was noted in fresh juice (FJ) (40%) and after mild heat treatment at 45 °C (T45) (46%). The highest BAc of total anthocyanins was also noted in the FJ (4.4%). The positive effect of the application of SCCD on the BAc of the delphinidin-3-O-glycosides was observed compared to T45 and thermal pasteurization at 85 °C (T85). Although SCCD did not significantly improve the BAc of vitamin C and total anthocyanins, the higher AC of SCCD samples after intestinal digestion (ABTS+• and DPPH•) and in dialysate (ABTS+•) compared to thermally treated was observed. The protocatechuic acid was detected by UPLC-PDA-MS/MS as the major metabolite formed during the digestion of delphinidin-3-O-rutinoside. This may indicate the influence of SCCD on improvement of the accessibility of antioxidants for digestion, thanks to which more metabolites with high antioxidant activity were released. 相似文献