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71.
The aim of this study was to investigate the cytotoxic activity of the Coriandrum sativum (C. sativum) ethanolic extract (CSEE) in neuroblastoma cells, chemically characterize the compounds present in the CSEE, and predict the molecular interactions and properties of ADME. Thus, after obtaining the CSEE and performing its chemical characterization through dereplication methods using UPLC/DAD-ESI/HRMS/MS, PM6 methods and the SwissADME drug design platform were used in order to predict molecular interactions and ADME properties. The CSEE was tested for 24 h in neuroblastoma cells to the establishment of the IC50 dose. Then, the cell death was evaluated, using annexin-PI, as well as the activity of the effector caspase 3, and the protein and mRNA levels of Bax and Bcl-2 were analyzed by ELISA and RT-PCR, respectively. By UHPLC/DAD/HRMS-MS/MS analysis, the CSEE showed a high content of isocoumarins-dihydrocoriandrin, coriandrin, and coriandrones A and B, as well as nitrogenated compounds (adenine, adenosine, and tryptophan). Flavonoids (apigenin, hyperoside, and rutin), phospholipids (PAF C-16 and LysoPC (16:0)), and acylglicerol were also identified in lower amount as important compounds with antioxidant activity. The in silico approach results showed that the compounds 1 to 6, which are found mostly in the C. sativum extract, obey the “Five Rules” of Lipinski, suggesting a good pharmacokinetic activity of these compounds when administered orally. The IC50 dose of CSEE (20 µg/mL) inhibited cell proliferation and promoted cell death by the accumulation of cleaved caspase-3 and the externalization of phosphatidylserine. Furthermore, CSEE decreased Bcl-2 and increased Bax, both protein and mRNA levels, suggesting an apoptotic mechanism. CSEE presents cytotoxic effects, promoting cell death. In addition to the promising results predicted through the in silico approach for all compounds, the compound 6 showed the best results in relation to stability due to its GAP value.  相似文献   
72.
Dichloro­(4,4′‐dipentyl‐2,2′‐bipyridine‐κ2N,N′)platinum(II), [PtCl2(C20H28N2)], adopts a discrete π–π stacking structure, where the alkyl chains are located in a random manner. In contrast, dichloro­(4,4′‐diheptyl‐2,2′‐bipyridine‐κ2N,N′)platinum(II), [PtCl2(C24H36N2)], forms a layer structure comprised of alkyl chain layers and paired coordination sites, as observed for analogous complexes with longer alkyl chains.  相似文献   
73.
A novel platinum(II)–diimine complex, [Pt(CN)2(H2dcphen)] ( 1 ; H2dcphen=4,7‐dicarboxy‐1,10‐ phenanthroline), was synthesized and its vapochromic shape‐memory behavior was evaluated. The as‐synthesized amorphous purple solid, [Pt(CN)2(H2dcphen)]?2 H2O ( 1 P ), exhibited vapochromic behavior in the presence of alcoholic vapors through transformation to a red, crystalline, porous, vapor‐adsorbed form, 1 R?vapor . The obtained 1 R?vapor complex released the adsorbed vapors upon heating without collapse of the porous structure. The vaporfree, porous 1 R?open could detect water or n‐hexane vapor, although these vapors could not induce 1 P ‐to‐ 1 R?vapor transformation, and 1 R?open could easily be converted to the initial 1 P by manual grinding. These results indicate that 1 is a new shape‐memory material that functions through formation and collapse of the porous framework with an emission change upon vapor‐adsorption and grinding; this enables it to exhibit vapor history and ON–OFF switching sensing functions.  相似文献   
74.
Purpose: Generally, stroke patients can walk and stand up fluidly but fulfill the sit-to-walk (STW) task with difficulty. The purpose of this study was to investigate the relationship between movement fluidity and motor strategy in the initial contact of the STW task. Method: Thirty stroke patients and ten healthy subjects performed the STW task from a sitting position, and their movement was measured by a motion analysis system. The differences in data between patients and healthy subjects were analyzed using the Mann-Whitney U test. The relationship between fluidity index (FI) and other indices (kinetic and kinematic data in STW, functional independence measure [FIM], and Fugl-Meyer Assessment [FMA]) were analyzed using Spearman''s rank correlation coefficient. Results: The stroke patients had lower FI values than the healthy subjects and exhibited shortened step length and prolonged duration from onset to the first stance leg off. FI values correlated with trunk flexure angle at initial contact, first step length, and maximum vertical floor reaction force. The independent level of the FIM of stair climbing and walking ability and the FMA of balance also correlated with FI. Conclusion: There is a possibility that poor balance is one of the reasons why stroke patients are unable to start walking fluently from the sitting position. To perform the STW fluidly, patients must start walking before the trunk extension is fully completed. The relationship between FI and indices of physical ability, namely stair climbing and balance, may have therapeutic benefits for coaching the STW task to stroke patients.  相似文献   
75.
We enclosed cisplatin (CDDP), an anticancer drug, inside single-wall carbon nanohorns (SWNH) with holes opened by being heated from room temperature to a target temperature (475-580 degrees C) in flowing dry air, with an increase rate of 1 degrees C/min. The optimum target temperature was found to be 500 degrees C, in terms of the least amount of CDDP deposited outside the SWNH, when the quantity of CDDP encapsulated inside the SWNH was 12 wt %. The incorporated CDDP was slowly released from the SWNH in phosphate buffer saline, and the released quantity was 80%, which was greatly improved from the previous value of 15%. This indicated that a CDDP-containing SWNH could become more potentially useful for biological applications.  相似文献   
76.
The intermolecular radical addition to chiral nitrones 2, 4, 5, and 16 was studied. The isopropyl radical addition to Oppolzer's camphorsultam derivative 2 of glyoxylic nitrone proceeded with excellent diastereoselectivity to give the desired isopropylated product 3a accompanied by the diisopropylated product 3b. A high degree of stereocontrol in the reaction of cyclic nitrone 4 was achieved. The ethyl radical addition to nitrone 4 with triethylborane afforded the desired ethylated product 9a accompanied by the diethylated product 10a and the ethylated nitrone 11a. To evaluate the utility of cyclic nitrone 4, several alkyl radicals were employed in the addition reaction, which afforded the alkylated products 9b-d with excellent diastereoselectivities. In the presence of Mg(ClO(4))(2), the ethyl radical addition to BIGN 16 afforded selectively syn isomers. In contrast, the alkyl radical addition to 16 took place even in the absence of Lewis acid to give anti isomers.  相似文献   
77.
A nitroxyl‐radical‐catalyzed oxidative coupling reaction between amines with an N‐protecting electron‐withdrawing group (EWG) and silylated nucleophiles was developed to furnish coupling products in high yields, thus opening up new frontiers in organocatalyzed reactions. This reaction proceeded through the activation of N‐halogenated amides by a nitroxyl‐radical catalyst, followed by carbon–carbon coupling with silylated nucleophiles. Studies of the reaction mechanism indicated that the nitroxyl radical activates N‐halogenated amides, which are generated from N‐EWG‐protected amides and a halogenation reagent, to give the corresponding imines.  相似文献   
78.
Benzofuro[2,3-b]quinoline ( Ia ) and its 11-methyl derivative ( Ib ) were synthesized by demethylcyclization of 3-(o-methoxyphenyl)-1,2-dihydroquinolin-2-ones (VIa,b). Benzofuro[2,3-b]quinoline-11-carboxylic acid (Id) was synthesized by chlorination followed by the action of potassium hydroxide of a lactone (IX) prepared by demethyl-cyclization of 3-(o-methoxyphenyl)-2-oxo-1,2-dihydroquinoline-4-carboxylic acid (VIII). Isomeric benzofuro[3,2-c]quinoline (Ha) and its 6-methyl derivative (IIb) were synthesized by demethyl-cyclization of 3-(o-methoxyphenyl)-1,4-dihydroquinolin-4-ones (XIa,b). Both the methyl derivatives (Ib and IIb) were converted to the carboxylic acids (Id and IId) through condensation with benzaldehyde followed by oxidation. The benzofuroquinolines (Ia,b,d and IIa,b) thus obtained were oxidized to the corresponding N-oxides (IIIa,b,d and IVa,b).  相似文献   
79.
Tetracationic water-soluble porphyrin (H(2)P(4+)) has been immobilized by pi-pi stacking interactions onto the skeleton of carbon nanohorns (CNH), without disrupting their pi-electronic network. The stable aqueous solution of the CNH-H(2)P(4+) nanoensemble was examined by both electron microscopy and spectroscopic techniques. The efficient fluorescence quenching of the H(2)P(4+) moiety in the CNH-H(2)P(4+) nanoensemble was probed by steady-state as well as time-resolved fluorescence emission spectroscopy, suggesting charge separation from the photoexcited H(2)P(4+) to CNH. In the presence of methyl viologen dication (MV(2+)) and a hole trap, accumulation of the reduced species of methyl viologen was observed by the photoillumination of CNH-H(2)P(4+), suggesting that the electron migration from the initially formed charge-separated state takes place. Transient absorption spectroscopy gave further insights on the transient species such as the charge-separated state (CNH(*-))-(H(2)P(4+))(*+), which was consumed in the presence of MV(2+) and hole shifter, leaving the reduced methyl viologen.  相似文献   
80.
We show that three-dimensional micro-optical components can be embedded in a photosensitive glass by a femtosecond (fs) laser. After exposure to the tightly focused fs laser beam, latent images are written inside the sample. Modified regions are developed by a postbaking process and then preferentially etched away in a 10%-dilute solution of hydrofluoric acid. After this process, hollow internal structures are formed that act as a mirror and a beam splitter. Furthermore, we find that postannealing smoothes the surfaces of the fabricated hollow structures, resulting in great improvement of their optical properties.  相似文献   
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