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161.
G. Ferro-Flores F. De M. Ramírez M.G. Martínez-mendoza C. Arteaga de Murphy M. Pedraza-lópez L. García-salinas 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(1):7-13
Lanreotide peptide was labeled with 153Sm-H1ETA and 188Re-MAG3 in order to evaluate whether or not their conjugation to the peptide produce significant differences of the in vitro lipophilicity with respect to the 188Re-lanreotide prepared by the direct labeling method (highly lipophilic). The differences of lipophilicity between the complexes, were evaluated using a reverse phase HPLC system. The measured lipophilicity of 153Sm-H1ETA-lanreotide, 188Re-MAG3-lanreotide and 188Re-lanreotide was taken to be the capacity factor [k" = (t
R-t
0)/t
0 where t
R is the retention time and t
0 is the dead time] for each of the complexes under identical chromatography conditions. Results showed that the in vitro lipophilicity decreased in the order 188Re-lanreotide (direct labeling), 188Re-MAG3-lanreotide and 153Sm-H1ETA-lanreotide. Since the last one has a capacity factor (k") similar to that of 188Re-MAG3, some renal elimination for 153Sm-H1ETA-lanreotide could be expected, which probably would reduce the unnecessary radiation dose to normal tissues. 相似文献
162.
Monotone Chemical Reaction Networks 总被引:2,自引:1,他引:2
Patrick De Leenheer David Angeli Eduardo D. Sontag 《Journal of mathematical chemistry》2007,41(3):295-314
We analyze certain chemical reaction networks and show that every solution converges to some steady state. The reaction kinetics
are assumed to be monotone but otherwise arbitrary. When diffusion effects are taken into account, the conclusions remain
unchanged. The main tools used in our analysis come from the theory of monotone dynamical systems. We review some of the features
of this theory and provide a self-contained proof of a particular attractivity result which is used in proving our main result. 相似文献
163.
164.
165.
166.
L. Moens F. De Corte A. Simonits Lin Xilei A. De Wispelaere J. De Donder J. Hoste 《Journal of Radioanalytical and Nuclear Chemistry》1982,70(1-2):539-550
A new method is presented to calculate with improved accuracy the absolute peak efficiency of cylindrical Ge and Ge(Li) detectors
for point, disk and cylinder sources, positioned at any source-detector distance. Moreover attention was paid to true-coincidence
effects. The method is extensively tested and applied for the analysis of reference materials. The accuracy turned out to
be 3% or better.
Research associate of the “Nationaal Fonds voor Wetenschappelijk Onderzoek”. 相似文献
167.
Beverina L Abbotto A Landenna M Cerminara M Tubino R Meinardi F Bradamante S Pagani GA 《Organic letters》2005,7(19):4257-4260
[graph: see text] Condensation of squaric acid with a number of differently substituted 2-pyrrolyl derivatives afforded three new classes of squaraines. Their sharp and intense absorption bands in the biological window (700-900 nm), inherent singlet oxygen generation capabilities, together with proper functionalization allowing good water solubility make them suitable candidates as new non-porphyrinic singlet oxygen photosensitizers for photodynamic therapy (PDT). 相似文献
168.
Giampiero Bettinetti Milena Sorrenti Laura Catenacci Franca Ferrari Silvia Rossi Ilaria Salvadeo Paolo Carraro 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):329-332
Triacetyl α-cyclodextrin, triacetyl β-cyclodextrin and triacetyl γ-cyclodextrin were tested as possible hydrophobic carriers
to prolong the release of hydrophilic teicoplanin (TCP). Physical–chemical characterization of individual components, drug-carrier
physical mixtures at 0.5, 0.67 and 0.75 mass fraction of carrier, and the respective interaction products by kneading or evaporative
crystallization under microwave irradiation was carried out using differential scanning calorimetry (DSC) and thermogravimetric
analysis (TGA). In vitro drug release in pH 7.4 phosphate buffer at 37 °C was determined by intrinsic dissolution rate (IDR)
measurements on non disintegrating compressed discs. Solid-state interactions of TCP with triacetyl α-cyclodextrin by evaporative
crystallization and kneading and with triacetyl β-cyclodextrin by evaporative crystallization (probably resulting in carrier
amorphization) were demonstrated. The role of carrier hydrophobicity, carrier mass fraction and preparation method of solid
drug-carrier combinations on solid-state drug-carrier interactions and slowing down of TCP release was assessed. Modulation
of drug release can be achieved using TCP-triacetyl γ-cyclodextrin combinations at 0.5 mass fraction of carrier. 相似文献
169.
170.
Chemiluminescence immunoassay for the detection and quantification of methyltestosterone residues in muscle tissue 总被引:1,自引:0,他引:1
Chemiluminescence as a detection method for immunoassay has successfully been applied to the measurement of methyltestosterone (MT) residues in muscle tissue. The sample is digested enzymatically, extracted with diethyl ether and purified on a Lipidex-5000 column. An optional clean-up utilized disposable C18 columns. As the luminescent label the N-(4-aminobutyl)-N-ethylisoluminol conjugate of MT was used. The antiserum was raised in a rabbit against MT-3-carboxymethyloxime-bovine serum albumin. The detection limit of the assay was 14 +/- 7 pg (n = 13), with a limit of quantification in muscle tissue of 0.125 ppb. 相似文献