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131.
The thermal properties of clothing products are influenced by external environmental parameters, such as temperature, humidity, air flow and parameters related to the user’s body, which mainly include temperature and humidity. Depending on the type of raw material, its thickness and the material manufacturing technique, clothing products are characterised by certain insulating properties to protect the human body from external factors. A multilayer system made of different material groups can change the thermal insulating capacity significantly, which cannot be determined by the testing of individual layers used in the production. In order to determine the influence of weather conditions on thermal insulation and air permeability, tests were carried out for two types of sleeping bags (summer and autumn) produced by the same manufacturer, differing in insulation thickness. Simulations were carried out using SolidWorks and verified using a Newton thermal mannequin. During tests, both the temperature (range from −20 °C to 20 °C) and humidity values were changed (range 40–80% humidity). For sleeping bags, the effective thermal insulation decreases along with the increase of temperature and decrease of humidity. It can be observed, for the autumn sleeping bags, that for a temperature of 20 °C and humidity of 60%, the thermal insulation is 1.063 m2·K·W−1, while for a temperature of −20 °C and humidity of 60% thermal insulation increases significantly and amounts to 1.111 m2·K·W−1. A similar situation occurs for the effective thermal insulation of a summer sleeping bag (20 °C/60% thermal insulation is 0.794 m2·K·W−1, while for −20 °C/60%—0.851 m2·K·W−1. During the tests, the humidity and temperature between the layers of the clothing system were also controlled, in order to learn more about the influence of these parameters on the thermal insulation properties of the sleeping bags. 相似文献
132.
Obniska J Tatarczyńska E Nikiforuk A Charakchieva-Minol S Duszyńska B 《Pharmacological reports : PR》2006,58(1):107-114
Two series of N-[(4-arylpiperazin-1-yl)-alkyl]-2-azaspiro[4.4]nonane (5-10) and [4.5]decane-1,3-dione (11-16) derivatives were synthesized and their serotonin 5-HT1A and 5-HT2A receptor affinities were determined. Compounds with the methylene spacer (5-7 and 11-13) exhibited low 5-HT1A/5-HT2A receptor affinity, in contrast to their ethylene analogues regarded as potent 5-HT1A ligands, especially those containing a cyclohexane moiety (14-16; Ki = 5.1, 2.7 and 4.3 nM, respectively) in the 3-position of the pyrrolidine-2,5-dione ring. Moreover, derivatives with 3-chloro substituent (10 and 14) showed distinct affinity for 5-HT2A receptors. The functional activity of compounds 10, 14, 15 and 16 was tested in vivo in the commonly used animal models. In those experiments, the tested compounds showed features of agonists of pre- and postsynaptic (14), agonists of presynaptic and antagonists of postsynaptic (10, 15), or agonists of postsynaptic (16) 5-HT1A receptors. Additionally, 10 and 16 exhibited properties of potential 5-HT2A receptor antagonists. The above results suggested a crucial role of the spacer between the amide fragment and 4-arylpiperazine moiety, as well as of the size of the cycloalkyl ring at the 3-position of pyrrolidine-2,5-dione ring in functional 5-HT1A/5-HT2A properties. 相似文献
133.
134.
Kubiak G Tomasik A Kawecki D Traczewska M Dola J Jacheć W Nowalany-Kozielska E 《Kardiologia polska》2012,70(5):533-5; discussion 536
A case of a 51-year-old woman with symptoms of non-ST-segment elevation acute coronary syndrome and concomitant atrial flutter is presented. Patient underwent atrioventricular septal defect repair in childhood. Coronary angiography showed total occlusion of left main coronary artery and massive collateral network originating from right coronary artery supplying entire left coronary artery. Ablation of atrial flutter had been performed and patient was subsequently submitted to mitral valve replacement, tricuspid valvuloplasty and coronary artery bypass grafting. The potential causes of left main occlusion are in this case discussed. 相似文献
135.
Caulfield MP Lynn T Gottschalk ME Jones KL Taylor NF Malunowicz EM Shackleton CH Reitz RE Fisher DA 《The Journal of clinical endocrinology and metabolism》2002,87(8):3682-3690
Definitive neonatal diagnosis of congenital adrenal hyperplasia (CAH) is frequently complicated by normal 17-hydroxyprogesterone levels in 21-hydroxylase-deficient patients, residual maternal steroids, and other interfering substances in neonatal blood. In an effort to improve the diagnosis, we developed a gas chromatography/mass spectrometry method for simultaneous measurement of 15 urinary steroid metabolites as early as the first day of life. Furthermore, we developed 11 precursor/product ratios that diagnose and clearly differentiate the four enzymatic deficiencies that cause CAH. Random urine samples from 31 neonatal 21-hydroxylase-deficient patients and 59 age-matched normal newborns were used in the development. Additionally, samples from two 11 beta-hydroxylase-deficient patients and one patient each for 17 alpha-hydroxylase and 3 beta-hydroxysteroid dehydrogenase deficiencies were used. The throughput for one bench-top gas chromatography/mass spectrometry instrument is 20 samples per day. Thus, this method affords an accurate, rapid, noninvasive means for the differential diagnosis of CAH in the newborn period without the need for invasive testing and ACTH stimulation. 相似文献
136.
137.
Kratz E Poland DC van Dijk W Katnik-Prastowska I 《Clinica chimica acta; international journal of clinical chemistry》2003,331(1-2):87-95
BACKGROUND: The degree of branching and types of fucosylation of glycans on alpha(1)-acid glycoprotein (AGP) have been found to be associated with alpha(1)-acid glycoprotein concentrations in human seminal plasma. The glycosylation pattern of alpha(1)-acid glycoprotein in seminal plasma obtained from men living in infertile couples can undergo alterations in relation to sperm analysis and/or alpha(1)-acid glycoprotein concentrations. METHODS: The glycosylation of alpha(1)-acid glycoprotein was studied upon the reactivity with specific lectins by crossed affinity immunoelectrophoresis (concanavalin A), and by glycoprotein lectin immunosorbent assay (Maackia amurensis and Sambucus nigra lectins), as well as high pH anion-exchange chromatography with pulsed amperometric detection. RESULTS: Nonsignificant differences in alpha(1)-acid glycoprotein glycan branching and degree of its sialylation were observed among the AGP derived from seminal plasmas in relation to spermiogram and sperm morphology. However, significant concentration-dependent differences were found in extent of branching and type of sialylation. CONCLUSIONS: The presence in seminal plasma of high concentrations of aberrantly glycosylated AGP molecules might be indicative for a chronic inflammatory condition in the reproductive tract, and can be used as additional tool to subdivide the seminal plasmas of men living in infertile couples. 相似文献
138.
Magazin M Poszepczynska-Guigné E Bagot M Boumsell L Pruvost C Chalon P Culouscou JM Ferrara P Bensussan A 《The Journal of investigative dermatology》2004,122(1):111-118
Circulating malignant Sezary cells are a clonal proliferation of CD4+CD45RO+ T lymphocytes primarily involving the skin. To study the biology of these malignant T lymphocytes, we tested their ability to migrate in chemotaxis assays. Previously, we had shown that the neuropeptide neurotensin (NT) binds to freshly isolated Sezary malignant cells and induces through NT1 receptors the cell migration of the cutaneous T cell lymphoma cell line Cou-L. Here, we report that peripheral blood Sezary cells as well as the Sezary cell line Pno fail to migrate in response to neurotensin although they are capable of migrating to the chemokine stromal-cell-derived factor 1 alpha. This is in contrast with normal circulating CD4+ or CD8+ lymphocytes, which respond to both types of chemoattractants except after ex vivo short-time anti-CD3 monoclonal antibody activation, which abrogates the neurotensin-induced lymphocyte migration. Furthermore, we demonstrate that neurotensin-responsive T lymphocytes express the functional NT1 receptor responsible for chemotaxis. In these cells, but not in Sezary cells, neurotensin induces recruitment of phosphatidylinositol-3 kinase, and redistribution of phosphorylated cytoplasmic tyrosine kinase focal adhesion kinase and filamentous actin. Taken together, these results, which show functional distinctions between normal circulating lymphocytes and Sezary syndrome cells, contribute to further understanding of the physiopathology of these atypical cells. 相似文献
139.
Reductions in the number of neuronal nicotinic acetylcholine receptors (nAChRs) have been shown to occur in connection with Parkinson's disease (PD), but it is still unclear which subtype of this receptor is affected. In the present study we examined various nAChR subtypes employing ligand binding, as well as levels of subunit protein and mRNA in the brains of PD patients and age-matched controls. Binding of [3H]epibatidine and levels of alpha3 mRNA in the caudate nucleus and temporal cortex, but not in the hippocampus were significantly decreased in the PD brain. The level of the alpha3 protein subunit was significantly reduced in all these brain regions but there was no change in the level of alpha4. The level of the beta2 protein subunit in the temporal cortex and hippocampus and the beta2 mRNA in the temporal cortex was lowered. Both the levels of the alpha7 subunit protein and [125I]alpha-bungarotoxin binding were significantly increased in the temporal cortex of PD patients whereas the alpha7 mRNA level was unchanged. These findings reveal selective losses of the alpha3- and beta2-containing nAChRs and an increase in the alpha7 nAChRs that might be related to the pathogenesis of PD. 相似文献
140.