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991.
Reyzer ML Hsieh Y Ng K Korfmacher WA Caprioli RM 《Journal of mass spectrometry : JMS》2003,38(10):1081-1092
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been used to directly analyze and image pharmaceutical compounds in intact tissue. The anti-tumor drug SCH 226374 was unambiguously determined in mouse tumor tissue using MALDI-QqTOFMS (QSTAR) by monitoring the dissociation of the protonated drug at m/z 695.4 to its predominant fragment at m/z 228.1. A second drug, compound A, was detected in slices of rat brain tissue following oral administration with doses ranging from 1-25 mg/kg. Quantitation of compound A from whole brain homogenates using routine high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) procedures revealed that concentrations of the drug in whole brain varied from a low of 24 ng/g to a high of 1790 ng/g. The drug candidate was successfully detected by MALDI-QqTOF in samples from each dose, covering a range of approximately two orders of magnitude. In addition, good correlation was observed between the MALDI-QqTOFMS intensities at each dose with the HPLC/MS/MS results. Thus the MALDI-MS response is proportional to the amount of drug in tissue. Custom software was developed to facilitate the imaging of small molecules in tissue using the MALDI-QqTOF mass spectrometer. Images revealing the spatial localization of SCH 226374 in tumor tissue and compound A in brain tissue were acquired. 相似文献
992.
G S Yang D M Chen Y Yang B Tang J J Gao H Y Aboul-Enein B Koppenhoefer 《Chromatographia》2005,62(7-8):441-445
The enantiomeric separation of 37 clinically used racemic basic drugs among 50 drugs was achieved using sulfated β-cyclodextrin
(S-β-CD) as chiral selector at pH2.5 and in the reversed polarity mode. The results obtained in this study were different
from the one obtained using neutral β-CD and its derivatives as chiral selectors. Using S-β-CD as chiral selector did not
require the presence of the substructure 4H to achieve chiral separation as observed with β-Cyclodextrin (β-CD) and its derivatives
since among the 37 separated drugs only 7 possess the 4H substructure. The chiral discrimination depends on the appropriate
interaction between the analyte and the sulfated β-cyclodextrin. 相似文献
993.
High performance thin-layer chromatography was used for the separation of nine therapeutically important and structurally similar β-adrenoceptor blocking drugs on silica gel plates. In situ scanning of the plate in the reflectance mode gave detection limits in the low nanogram range depending on the individual drug and the wavelength selected for its determination. Scanning the HPTLC plate at several wavelengths can be used to aid the identification of partially resolved components. Continuous development and continuous multiple development techniques are compared for the simultaneous separation of the drug mixture. 相似文献
994.
Kenneth L. Kirk 《Journal of fluorine chemistry》2006,127(8):1013-1029
Advances in the development of newly developed fluorinated drugs, approved or in clinical trials, as organized by biological targets/disease states, are reviewed. In a few cases, compounds in early stages of development will be discussed, particularly where new promising targets are involved. Important topics such as anticancer and antiviral drugs were covered in the two previous reviews in this series. Included herein will be fluorinated drugs for treatment of diseases of the central nervous system, various cardiovascular diseases and obesity, antibacterial agents, and antifungal therapy. 相似文献
995.
新型环糊精衍生物单6-O-苯基胺甲酰基-β-环糊精的合成及其在手性药物毛细管区带电泳拆分中的应用 总被引:6,自引:4,他引:6
合成了新型的环糊精衍生物单6-O-苯基胺甲酰基—β-环糊精,并对合成产物进行了表征。以新型环糊精衍生物为手性选择剂,考察了手性选择剂浓度、缓冲液PH值和浓度及有机溶质对8种手性药物对映体的毛细管电泳分离的影响。结果表明:手性选择剂浓度和缓冲液PH值是影响药物对映体分离的重要因素,有机溶质亦对分离有很大影响。单6-O-苯基胺甲酰基—β-环糊精能使所研究的8种手性药物中的5种达基线分离,3种达部分分离。而在同样条件下.β-环糊精仅能使上述药物中的菜心安达部分分离(及。=0.67),这说明我们合成的环糊精衍生物手性拆分能力要强于天然环糊精。我们还就单6-O-苯基胺甲酰基-β-环糊精对手性药物可能的拆分机理进行了探讨。 相似文献
996.
This paper reports the research results which the anticancer drugs Ara-C with controlled slow release were made by radiation induced polymerization of monomers such as methacrylates at room temperature. Our studies showed that not only hydrophilic synthetic polymers but also hydrophobic polymers such as hydrophobic methacrylates (including MMA, EMA, and BMA) could be used to the immobilization. In vitro the rate of drugs release was controlled by the many factors such as the content of drugs, the monomer material, the crosslinking agent, the irradiation dose and the water content, etc. 相似文献
997.
D. Attwood R. Blundell V. Mosquera M. Garcia J. Rodriguez 《Colloid and polymer science》1994,272(1):108-114
The apparent molar volumes and adiabatic compressibilities of aqueous solutions of the amphiphilic tricyclic drugs, chlorpromazine, promethazine, promazine and imipramine have been determined from measurements of density and ultrasound velocity. Positive deviations of the apparent molar volume from the Debye-Hückel limiting law in dilute solution indicate possible premicellar association. The changes of molar volume and compressibility accompanying aggregate formation were appreciably smaller than those of typical surfactants, suggesting a more tightly packed aggregate. The magnitude of the increase in molar compressibility on micellisation of imipramine decreased with temperature rise between 20 and 35°C. The results are discussed in terms of the structure and hydration of the drug aggregates. 相似文献
998.
Carlos Alemán 《Theoretical chemistry accounts》1998,99(5):312-319
A quantum mechanical study of the conformational preferences of Hoechst 33258, a synthetic minor groove-binding drug, has
been performed in both gas-phase and aqueous solution. Gas-phase calculations were performed at the HF/6-31G(d) and MP2/6-31G(d) levels of theory, whereas calculations in the aqueous solution phase were performed using the PCM model with the 6-31G(d) basis set. The molecule was divided into three fragments, which were submitted to a systematic and detailed conformational
study. The results clearly indicate that Hoechst 33258 does not adopt a planar conformation in either the gas-phase or aqueous
solution. Thus, a folded conformation is not induced by binding of the molecule to DNA, but is an intrinsic property of the
compound.
Received: 3 March 1998 / Accepted: 29 May 1998 / Published online 19 August 1998 相似文献
999.
Large-volume sample stacking using the electroosmotic flow (EOF) pump (LVSEP) has been used to analyze some nonsteroidal anti-inflammatory drugs (NSAIDs) in water samples. With methanol as the run buffer solvent to suppress the EOF, sensitivity was enhanced by 80-100-fold. The sample for the analysis of real water sample was pretreated by solid-phase extraction (SPE). When the method was based on off-line SPE-LVSEP-CE, sensitivity improved by as much as 1000 times. 相似文献
1000.
rico Marlon de Moraes Flores Fabiana E. Barcelos da Silva Eliane Pereira dos Santos Fvero Reisdorfer Paula Juliano Smanioto Barin Renato Zanella Valderi Luiz Dressler Celso Figueiredo Bittencourt 《Spectrochimica Acta Part B: Atomic Spectroscopy》2002,57(12):2095-2102
A procedure for the determination of arsenic by batch hydride generation atomic absorption spectrometry (HG AAS) in commercial samples of injectable drugs, containing high concentrations of Sb(V), is described. The procedure is based on the complexing effect for Sb of citric, oxalic and acetic acids as reaction media. Aqua regia was used for sample digestion prior to As determination by HG AAS. The following experimental conditions for the determination of total As, as As(V), were evaluated: the acid medium and its concentration, sodium tetrahydroborate concentration, purge time, and influence of the different oxidation states of As. The effect of the delay time after mixing of sample and acid solution was also studied. Optimized conditions were: 10% (m/v) citric acid, 1.5% (m/v) sodium tetrahydroborate solution and 30 s for purge time. A delay time of 1 h was required after the digested sample had been mixed with citric acid, before As determination could be carried out. No interference on As(III) and As(V) signals was observed in the presence of up to 1 mg Sb(V). The tolerance limits for Ni(II), Cu(II) and Pb(II) were 1 mg, 100 μg and 100 μg, respectively. Recovery tests for As(III) and As(V) resulted in values between 97 and 101%. Characteristic mass and detection limit (3σ), using the recommended conditions, were 0.52 and 0.8 ng, respectively, for total As. 相似文献