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121.
Gregorio Sánchez Jorge VivesJosé L Serrano José PérezGregorio López 《Inorganica chimica acta》2002,328(1):74-80
The synthesis of palladacyclopentadiene derivatives with the mixed-donor bidentate ligands o-Ph2PC6H4CHNR (N∧P) has been achieved. The new complexes of general formula [Pd{C4(COOMe)4}(o-Ph2PC6H4CHNR)] [R=Me (1), Et (2), iPr (3), tBu (4), NHMe (5)] have been prepared by reaction between the precursor [Pd{C4(COOMe)4}]n and the corresponding iminophosphine. The polymer complex [Pd{C4(COOMe)4}]n also reacts with pyridazine (C4H4N2) to give the insoluble dinuclear complex [Pd{C4(COOMe)4}(μ-C4H4N2)]2 (6), which has been successfully employed as precursor in the synthesis of pyridazine-based palladacyclopentadiene complexes. The reaction of 6 with tertiary phosphines yielded complexes containing an N,P-donor setting of formula [Pd{C4(COOMe)4}(C4H4N2)(L)] (L=PPh3 (7), PPh2Me (8), P(p-MeOC6H4)3 (9), P(p-FC6H4)3 (10)). The new complexes were characterized by partial elemental analyses and spectroscopic methods (IR, 1H, 19F and 31P NMR). The molecular structure of complex 3 has been determined by a single-crystal diffraction study, showing that the iminophosphine acts as chelating ligand with coordination around the palladium atom slightly distorted from the square-planar geometry. 相似文献
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The progress achieved by several groups in the field of computational protein design shows that successful design methods include two major features: efficient algorithms to deal with the combinatorial exploration of sequence space and optimal energy functions to rank sequences according to their fitness for the given fold. 相似文献
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Poly(vinyl alcohol), PVA, is amenable to several structural modifications because of the presence of the hydroxyl moiety in the backbone. The chemical versatility of this polymer can be used for the obtainment of new wall-to-wall pH-responsive PVA chemical hydrogels and for the preparation of air-filled microspheres, for example, microbubbles. Here, we report on the characterization of the physical and chemical properties of these novel networks that can be potentially used in different biomedical applications as controlled drug delivery and as ultrasonic contrast agent. 相似文献
127.
The synergistic interaction between xanthan and glucomannan in solution and in the gel phase has been studied by circular dichroism spectroscopy and differential scanning calorimetry. The study in solution of the polysaccharidic mixture indicates a preferred stoichiometry of the interaction corresponding to a weight fraction of xanthan around 0.55. This finding is in reasonable agreement with the differential scanning calorimetry measurements carried out on the gel phase. Models from conformational analysis based on these results were formulated in terms of 1:1 and 2:1 Konjac glucomannan/xanthan molecular assemblies. The experimental and calculation results clearly indicate the involvement of the side chains of xanthan and suggest that the ordered portions of the macromolecular complex in solution act in the gel phase as junction zones. 相似文献
128.
González Díaz H Olazabal E Castañedo N Sánchez IH Morales A Serrano HS González J de Armas RR 《Journal of molecular modeling》2002,8(8):237-245
A novel method for in silico selection of fluckicidal drugs is introduced. Two QSARs that permit us to discriminate between fasciolicide and non-fasciolicide drugs (the first) and to outline some conclusions about the possible mechanism of action of a chemical (the second) are performed. The first model correctly classified 93.85% of compounds in the training series and 89.5% of the compounds in the predicting one. This model correctly classified 87.7, 93.8, 92.2 and 93.9% of compounds in leave- n-out cross validation procedures when n takes values from 2 to until 6. The model seems to be stable in around 92% of good classification in leave- n-out cross validation analysis when n>6. The second model correctly classified 70% of non-fasciolicide compounds, 85.71% of beta-tubulin inhibitors and 100% of proton ionophores in the training set. This model recognizes as proton ionophores 100% of any nitrosalicylanilides in the predicting series. Both models have a low p-level <0.05. Finally, the experimental assay of six organic chemicals by an in vivo test permit us to carry out an assessment of the model with a fairly good 100% agreement between experiment and theoretical prediction. 相似文献
129.
Velasco A Román C Aragüés M Noguera X Ventura C Lerís E 《Revista iberoamericana de micología》2002,19(3):169-172
Different clinical studies have demonstrated flutrimazole's efficacy in the treatment of superficial dermatomycoses when administered either twice daily or once daily for four weeks. The aim of the present study was to compare both dosing schedules for the treatment of superficial dermatomycoses. In this randomized, controlled, double blind study, we included 84 patients suffering superficial dermatophytosis (confirmed by microscopic examination (KOH) and culture) susceptible for topical monotherapy. Forty-one patients received flutrimazole 1% twice daily (TD) and forty-three once daily (OD) for four weeks. The efficacy of treatment was evaluated by clinical and mycological criteria at the end of treatment (D28) and after four weeks without treatment (D58). Clinical and mycological cure rates on D28 were 50% with TD and 65% with OD treatment. Only considering clinical evaluation, clinical cure rates on D28 were 63% (TD) and 70% (OD). Also, clinical and mycological cure rates on D56 were 65% with TD and 72% with OD treatment. Only considering clinical evaluation, clinical cure rates on D56 were of 68% (TD) and 72% (OD). The overall tolerability was similar in both treatment groups. The efficacy assessment at the end of treatment (D28) and four weeks after treatment discontinuation (D56) showed that the OD treatment is not inferior to the TD treatment, with similar clinical and mycological cure rates and clinical cure rates in both cases. The OD administration of flutrimazole cream 1% is the most appropriate dosing schedule as it provides the same efficacy, it improves patient's compliance and the cost per day of treatment. 相似文献
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