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81.
Christodoulakos G Lambrinoudaki I Panoulis C Papadias C Economou E Creatsas G 《Fertility and sterility》2004,82(3):634-638
OBJECTIVE: To investigate the effect of continuous combined hormone therapy and raloxifene on serum VE-cadherin. DESIGN: The study was double blinded, with a placebo run-in period of 28-50 days. SETTING: University menopause clinic. PATIENT(S): Twenty-eight healthy postmenopausal women devoid of climacteric complaints. INTERVENTION(S): Subjects were randomized to 17beta-estradiol (2 mg) + norethisterone acetate (1 mg; E(2)-NETA) or raloxifene hCL (60 mg) for a period of 6 months. MAIN OUTCOME MEASURE(S): Serum VE-cadherin, which was estimated at baseline and at month 6. RESULT(S): Serum VE-cadherin decreased significantly in both E(2)-NETA and raloxifene groups (raloxifene baseline +/- SD: 1.17 +/- 0.44 ng/mL, 6 months: 0.82 +/- 0.29 ng/mL; E(2)-NETA baseline: 1.19 +/- 0.47 ng/mL, 6 months: 0.92 +/- 0.49 ng/mL). Percentage changes from baseline were -21.7 +/- 24.3 for E(2)-NETA and -26.0 +/- 20.6 for raloxifene. CONCLUSION(S): The effect of E(2)-NETA and raloxifene suggests that these drugs may preserve interendothelial junction integrity and control vascular permeability. Although this effect may influence the progress of the atheromatous lesion, its clinical impact on coronary artery disease (CAD) remains uncertain. 相似文献
82.
Effects of Cordyceps militaris extract on angiogenesis and tumor growth 总被引:21,自引:0,他引:21
INTRODUCTIONAngiogenesis is the process of new blood vesselformation from existing blood vessels and a natural re-sponse of tissues to ischemia[1]. The steps of angio-genesis involve proteolytic degradation of extracelluarmatrix, endothelial cell-matrix adhesion, migration,proliferation, and differentiation[2]. This biological re-action is often associated with some diseases, such assolid tumor[3], diabetic retinopathy[4], and rheumatoidarthritis[5].Tumor formation requires the developm… 相似文献
83.
Bartoszyk GD Van Amsterdam C Greiner HE Rautenberg W Russ H Seyfried CA 《Journal of neural transmission (Vienna, Austria : 1996)》2004,111(2):113-126
Summary. Sarizotan exhibited high affinities only to serotonin 5-HT1A receptors and dopamine DA D4>D3>D2 receptors with the profile of a 5-HT1A agonist and DA antagonist demonstrated by the inhibition of cAMP-stimulation and guinea pig ileum contraction, decreased accumulation of the 5-HT precursor 5-hydroxytryptophan and increased levels of 5-HT metabolites, increased accumulation of DA precursor dihydroxyphenylalanine (DOPA) and the reduced levels of DA metabolites in intact rats. However, sarizotan at higher doses decreased DA precursor accumulation in reserpinized rats and induced contralateral rotational behavior in unilaterally substantia nigra lesioned rats, indicating some intrinsic dopaminergic activity; at D2 receptors sarizotan may act as a partial agonist, depending on the dopaminergic impulse flow. Sarizotan represents a new approach for the treatment of extrapyramidal motor complications such as l-DOPA-induced dyskinesia in Parkinsons disease. 相似文献
84.
Paluchowska MH Bojarski AJ Bugno R Charakchieva-Minol S Wesołowska A 《Archiv der Pharmazie》2003,336(2):104-110
Structure-activity relationship studies of a series of novel 4, 6-disubstituted 2-(1-piperazinyl)pyridines were conducted to revise our model of serotonin 5-HT(2A) receptor antagonist. Target compounds were synthesized using the benzotriazole-assisted Katritzky method. The majority of those compounds were found to be selective 5-HT(2A)/5-HT(1A) receptor ligands, though less potent than their previously described pyrimidine counterparts. In particular, the three compounds 6-8 showed the highest 5-HT(2A) receptor affinity (K(i) = 34-78 nM) and were classified as 5-HT(2A) antagonists in in vivo experiments. The influence of the structural modifications on the in vitro results was discussed; however, the elucidation of the role of the central core system requires further studies. 相似文献
85.
A synthesis of two new active substances, DOMCl (1-(4-chloromethyl-2, 5-dimethoxyphenyl)-2-propanamine; 2) and DOMOM (1-(2, 5-dimethoxy-4-methoxymethylphenyl)-2-propanamine; 3), was developed. Unexpectedly, the Blanc reaction permitted successful synthesis of 2, 5-dimethoxyphenylpropylamine derivatives having a substituted methyl group in position 4 since solvation of the reactant occurs during the reaction. Afterwards, their affinities towards the 5-HT(2A) receptor were examined in 5-HT(2A) radioligand receptor binding assays. The study of these substances is of considerable interest because they were predicted, by preliminary molecular modeling studies based on mescalin units, to be potential new hallucinogens that should be added to the list of substances prohibited by law. It was assumed that DOMCl would be 82 times more potent as a hallucinogen than mescalin, and DOMOM would be 94 times more potent. The 5-HT(2A) radioligand receptor binding studies showed that the affinities of DOMCl and DOMOM for the 5-HT(2A) receptor are less than expected but are nevertheless 1.6 and 8.7 times higher, respectively, than that of mescalin. Therefore, scheduling these substances as potential drugs of abuse might be considered. 相似文献
86.
87.
Purpose. A new mucus-secreting in vitro drug absorption model based on monolayers of goblet-cell like sub-clones of the human colon carcinoma cell line HT29 obtained by methotrexate (MTX) treatment was investigated.
Methods. Twelve sub-clones were isolated and characterized by light microscopy (LM), transelectron microscopy (TEM), confocal laser scanning microscopy (CLSM), transepithelial electrical resistance (TEER) and the transport of a paracellular marker FITC-Dextran (Mw 4400) (FD-4).
Results. Significant differences of microscopical appearance, TEER-values and permeability of FD-4 between the sub-clones were evident. However, two of them, namely MTX-D1 and MTX-E12, formed tight confluent monolayers with a thick mucus-layer on the apical surface. They were used to compare the apparent permeability coefficient (Papp) of a series of lipophilic drugs, which should be affected by the mucus-layer, namely barbiturates (barbituric acid, barbital, phenobarbital, methylphenobarbital and heptabarbital) and testosterone, as a reference, to mucus-free Caco-2 cells. The permeability of drugs with a partition coefficient (log P) > 1 was decreased in the mucus-producing cell lines. Testosterone, the most lipophilic compound, showed a decrease of up to 43%.
Conclusions. We demonstrated that the mucus layer is a significant barrier to drug absorption for lipophilic drugs. In conclusion, our model may serve as a suitable in-vitro cell culture model to study the influence of the mucus layer on drug diffusion. 相似文献
88.
肾衰91冲剂对不同慢性肾衰大鼠毒素作用的实验研究 总被引:2,自引:0,他引:2
杨爱东 《中国中医基础医学杂志》1999,5(9):25-28
目的探讨肾衰91冲剂对不同慢性肾衰大鼠毒素作用的机理。方法采用肾衰91冲剂治疗0.75%腺嘌呤和plat法诱发慢性肾衰。结果与模型组相比,肾衰91冲剂组血尿素氮、肌酐、中分子物质、甲基胍、胍基琥珀酸、磷显著降低,钙升高,两组上述各项指标均有显著性差异(P<0.05~0.01)。结论肾衰91冲剂组有降低尿毒证毒素,调整钙磷代谢紊乱的作用。 相似文献
89.
90.
Matthias M. Herth Vasko Kramer Frank Rösch 《Journal of labelled compounds & radiopharmaceuticals》2009,52(6):201-207
5‐HT1A receptors are involved in a variety of psychiatric disorders and in vivo molecular imaging of the 5‐HT1A status represents an important approach to analyze and treat these disorders. We report herein the synthesis of three new fluoroethylated 5‐HT1A ligands (AH1.MZ, AH2.MZ and AH3.MZ) as arylpiperazine derivatives containing a norbornene group. AH1.MZ (Ki= 4.2 nM) and AH2.MZ (Ki=30 nM) showed reasonable in vitro affinities to the 5‐HT1A receptor, whereas AH3.MZ appeared to be non‐affine toward the 5‐HT1A receptor. The receptor profile of AH1.MZ and AH2.MZ showed selectivity within the 5‐HT system. 18F‐labelling via [18F]FETos to [18F]AH1.MZ was carried out in radiochemical yields of >70%. The final formulation of injectable solutions including [18F]FETos synthon synthesis, radiosynthesis and semi‐preparative high‐performance liquid chromatography (HPLC) separation took no longer than 130 min and provided [18F]AH1.MZ with a purity of >98% as indicated by analytical HPLC analyses. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献