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61.
A series of new furanopeptides (3) are prepared by the coupling of arylsubstituted furoic acids (1) with amino acid methyl esters, di and tetra-peptide methyl esters using dicyclohexyl carbodiimide (DCC) as coupling agent. Some of the newly synthesized compounds are characterized on the basis of IR, 1H NMR, mass spectral data and elemental analysis. Some of the selected compounds are also tested for their antibacterial properties. 相似文献
62.
The objective of this study was to evaluate the in vitro and ex vivo percutaneous absorption of chlorpheniramine maleate (CPM) from different hydrogel formulations. Various concentrations of polymers, including hydroxypropylmethylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC) and methyl cellulose (MC) were used in the hydrogel formulations. All experiments were conducted using cellulose dialysis membrane. The passive permeation of CPM was affected by the polymer concentrations. The effect of each polymer on the release rate of CPM was found to be statistically different (P<0.05). The formulation which exhibited maximum drug release through cellulose membrane was then used with other membranes namely polyurethane membrane, rat skin and human skin. The release rate of CPM from different membranes was found to be statistically different (P<0.05). Within the different diffusional barriers rat skin was found to be best alternative to human skin. It seems suitable the use of cellulose derivatives for topical application of CPM to obtain high therapeutic concentration at the application site. The synthetic membranes can be used to assess product performance in quality assurance but give little indication of its performance ex vivo. 相似文献
63.
A randomized controlled trial of a new ovule formulation of ornidazole for the treatment of bacterial vaginosis 总被引:3,自引:0,他引:3
Baloğlu E Ozyazici M Baloğlu A Ova L 《Journal of clinical pharmacy and therapeutics》2003,28(2):131-136
OBJECTIVE: To compare the efficacy of 500 mg ornidazole vaginal ovules (VO) and vaginal tablets (VT) in the treatment of bacterial vaginosis. METHOD: Patients were allocated at random to one group of 50 subjects to be treated with a VO (500 mg) prepared in our laboratory and to a second group of 50 subjects to be treated with a VT of ornidazole (500 mg). Therapeutic efficacy was assessed by Nugent's scoring system and clinical criteria (Amsel's criteria) before and 1 week after treatment. RESULTS: At the first follow-up visit, complete disappearance of the signs and symptoms or highly significant reduction in intensity of symptoms was observed in both treatment groups. No significant difference was evident between the two ornidazole formulations. 相似文献
64.
We identified two cases of chronic active hepatitis with liver fibrosis induced by lipid lowering drugs of the statin and fibrate classes despite regular monitoring of transaminases. There are few reports of clinically significant hepatitis induced by these drugs and even fewer cases of fibrosis. Given the growing use of these drugs, there are implications for monitoring patients on long-term therapy for liver damage. 相似文献
65.
Hitendra N. Karade B. N. Acharya Manisha Sathe M. P. Kaushik 《Medicinal chemistry research》2008,17(1):19-29
A series of thiazole-derived N-Boc amino acids were synthesized and evaluated as targeted potential antimalarials against
plasmepsins II enzyme of malaria parasite Plasmodium falciparum. All the compounds showed moderate to good activity. Compounds 3f and 3g were found to have highest the 50% inhibitory concentration (IC50) values (3.45 μM and 4.89 μM, respectively) against Plasmodium falciparum. The compounds docked to the active site of plasmepsin II. Most of the compounds were found to interact with the catalytic amino acids ASP34 and ASP214 of plasmepsin II. A good correlation was observed between binding energy and antiparasitic activity of the thiazole derivatives. 相似文献
66.
《中药新药与临床药理》1999,10(6):333-335
Eighteen
falciparumn malaria patients with gametocytemia were randomly allocated to 2
groups,treated respectively with dihydroartemisinin (DATM) tablets at a total dose of 360
mg over 5 days and with oral quinine sulfate (QN) at a total dose of 10 5000 mg over 7
days. Peripheral gametocyte counts were done daily in all patients until its
disappearance. Blood samples were taken on D0, D4, D7, D10, D14, D21 and D28 from the
patients to perform infectivity tests to Anopheles dirus. The result showed that the mean
clearance times of PFG were 21.8±5.2 days in DATM group and 31.5±8.7 days in QN group
respectively. And in DATM group, the infectivity tests were positive in 6 cases only. In
those 6 positive cases, the numbers of the positive infectivity on D4, D7, D10, D14 and
D21 were 6/6,6/6,2/6,0/6 and 0/6 respectively. While the 4 negative cases on D0 remained
negative infectivity on D4, D7, D10, D14. In QN group, the infectivity tests were positive
in 4 cases too on D0, the numbers of positive cases on D4, D7, D10, D14, D21 and D28 were
8/8,8/8,8/8,8/8,2/8 and 0/8 respectively. These indicate that QN cannot inhibit
P.Falciparum at sexual stage, while DATM has a remarkable inhibitory effect, and may
prevent the immatured PFG that was failure to infect An. dirus on D0 from maturing. 相似文献
67.
合成了化合物2-氯-5-(5,6-二基-1,4-氧硫杂环己二烯-3-甲酰氨基)苯甲酸异丙酯(UC84),并以其为先导物合成了11个未见报道的衍生物,活性筛选表明该类化合物有明显的抗单纯疱疹病毒(HSV)和乙肝病毒(HBV)活性。 相似文献
68.
Three dimensional QSAR studies for antihistamine and antibradykinin effects of new piper azine derivatives were conducted using the comparative molecular field analysis. Electro static and steric factors, but not hydrophobic factor, of the synthesized compounds were correlated with the antagonistic effect. 相似文献
69.
Ten compounds were isolated from Qianliang tea, a kind of dark tea fully fermented from the leaves of Camellia sinensis (L.) O. Kuntze var. sinensis, and identified as N-(2-hydroxyphenyl)-2-pyrrolidinone (1), p-hydroxyacetophenone (2), salicifoliol (3), (-)-3-hydroxy-β-ionone (4), p-hydroxy ethyl cinnamate (5), ethyl 4-(sulfooxy)benzoate (6), (+)-matairesinol (7), (-)-pinoresinol (8), (+)-lirioresinol-A (9), and caffeine (10), among which compound 1 was isolated as a new natural product, and compound 6 was isolated from Theaceae family for the first time. Compounds 3, 4, 5, 7, 8, and 9 were isolated from this species for the first time. 相似文献
70.
Jiansong Fang Ping Wu Ranyao Yang Li Gao Chao Li Dongmei Wang Song Wu Ai-Lin Liu Guan-Hua Du 《药学学报(英文版)》2014,4(6):430-437
In this study two genistein derivatives (G1 and G2) are reported as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), and differences in the inhibition of AChE are described. Although they differ in structure by a single methyl group, the inhibitory effect of G1 (IC50=264 nmol/L) on AChE was 80 times stronger than that of G2 (IC50=21,210 nmol/L). Enzyme-kinetic analysis, molecular docking and molecular dynamics (MD) simulations were conducted to better understand the molecular basis for this difference. The results obtained by kinetic analysis demonstrated that G1 can interact with both the catalytic active site and peripheral anionic site of AChE. The predicted binding free energies of two complexes calculated by the molecular mechanics/generalized born surface area (MM/GBSA) method were consistent with the experimental data. The analysis of the individual energy terms suggested that a difference between the net electrostatic contributions (ΔEele+ΔGGB) was responsible for the binding affinities of these two inhibitors. Additionally, analysis of the molecular mechanics and MM/GBSA free energy decomposition revealed that the difference between G1 and G2 originated from interactions with Tyr124, Glu292, Val294 and Phe338 of AChE. In conclusion, the results reveal significant differences at the molecular level in the mechanism of inhibition of AChE by these structurally related compounds.KEY WORDS: Genistein derivatives, Acetylcholinesterase (AChE), Kinetics analysis, Molecular docking, Molecular dynamics simulation, MM/GBSAAbbreviations: ACh, acetylcholine; AChEIs, acetylcholinesterase inhibitors; AChE, acetylcholinesterase; AD, Alzheimer׳s disease; BuChE, butyrylcholinesterase; BuSCh, S-butyrylthiocholine chloride; CAS, catalytic active site; DTNB, 5,5′-dithiobis-(2-nitrobenzoic acid); GAFF, generalized AMBER force field; G1, 3-(4-methoxyphenyl)-7-(2-(piperidin-1-yl)ethoxy)-4H-chromen-4-one; G2, (S)-3-(4-methoxyphenyl)-7-(2-(2-methylpiperidin-1-yl)ethoxy)-4H-chromen-4-one; iso-OMPA, tetraisopropyl pyrophosphoramide; MD, molecular dynamics; MM/GBSA, molecular mechanics/generalized born surface area; PAS, peripheral anionic site; PDB, protein data bank; PME, particle mesh Ewald; RMSD, root-mean-square deviation; S-ACh, acetylthiocholine iodide; ΔEele, electrostatic energy contribution; ΔEMM, gas-phase interaction energy between receptor and ligand; ΔEvdw, van der Waals energy contribution; SASA, solvent accessible surface area; ΔGexp, experimental binding free energy; ΔGGB, polar desolvation energy term; ΔGpred, total binding free energy; ΔGSA, nonpolar desolvation energy term; ΔS, conformational entropy contribution 相似文献