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101.
OBJECTIVE: We assessed a new estradiol (E2) immunoassay on the Architect-i2000 (Abbott Laboratories) for monitoring ovulation stimulation for IVF-ET and re-establishing clinical cut-off points. The method has been modified to improve E2 measurements especially at normal and low concentrations. DESIGN AND METHOD: E2 was determined for 552 samples, from 83 women, presenting normal follicular status and undergoing 100 cycles of IVF treatment. We assessed the value of this assay for down-regulation of E2 concentration limit using gonadoliberin-releasing hormone agonist (GnRHa), and monitoring of the ovarian hyperstimulation, expected range of E2 per mature follicle prior to the administration of exogenous hCG and day 3 concentration limit. We compared results with our routine method (E2-6II Advia-Centaur; Siemens-Diagnostics) for which decision-making values were known. RESULTS: Considering E2 concentrations obtained with the new Architect-i2000 assay for patients treated with GnRHa for 2 weeks, the cutoff-point for ovarian down-regulation should be set down at 110 pmol/L to maintain 100% of sensitivity. Considering day 3 concentration limit determination, results were not significantly different from those obtained with our routine method. The mean E2 values per mature follicle fell into the range generally expected. CONCLUSION: E2 determination with the new E2 Architect-i2000 assay could be used to monitor ovulation, in patients undergoing IVF-ET, in combination with transvaginal ultrasound. 相似文献
102.
G Lavie ; Y Mazur ; D Lavie ; AM Prince ; D Pascual ; L Liebes ; B Levin ; D Meruelo 《Transfusion》1995,35(5):392-400
103.
Paloma Flórez Borges Pilar Pérez Lozano Encarna García Montoya Montserrat Mi?arro Josep R Ticó Enric Jo Josep M Su?e Negre 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2014,22(1)
Background
A new, simple and accurate stability-indicating reverse phase high performance liquid chromatography method was developed and validated during the early stage of drug development of an oral lyophilizate dosage form of cetirizine dihydrochloride.Methods
For RP-HPLC analysis it was used an Eclipse XDB C8 column 150 mm × 4.6 mm, 5 μm (Agilent columns, Barcelona, Spain) as the stationary phase with a mobile phase consisted of a mixture of 0.2 M K2HPO4 pH 7.00 and acetonitrile (65:35, v/v) at a flow rate of 1 mL min −1. Detection was performed at 230 nm using diode array detector. The method was validated in accordance with ICH guidelines with respect to linearity, accuracy, precision, specificity, limit of detection and quantification.Results
The method results in excellent separation between the drug substance and its stress-induced degradation products. The peak purity factor is >950 for the drug substance after all types of stress, which confirms the complete separation of the drug substance peak from its stress induced degradation products.Regression analysis showed r2 > 0.999 for cetirizine dihydrochloride in the concentration range of 650 μg mL −1 to 350 μg mL−1 for drug substance assay and a r2 > 0.999 in the concentration range of 0.25 μg mL−1 to 5 μg mL−1 for degradation products. The method presents a limit of detection of 0.056 μg mL −1 and a limit of quantification of 0.25 μg mL−1. The obtained results for precision and accuracy for drug substance and degradation products are within the specifications established for the validation of the method.Conclusions
The proposed stability-indicating method developed in the early phase of drug development proved to be a simple, sensitive, accurate, precise, reproducible and therefore useful for the following stages of the cetirizine dihydrochloride oral lyophilizate dosage form development. 相似文献104.
105.
M.A. Pabón C.E. Navarro J.C. Osorio N. Gómez J.P. Moreno A.F. Donado H.C. Pérez E. Lozano 《Transplantation proceedings》2014,46(9):2957-2965
BackgroundHLA class I molecules are divided into classic (Ia) and nonclassic (Ib). Nonclassic HLA molecules (E, F, and G) have acquired relevance owing to their immunomodulatory properties and possible repercussions for induction of tolerance in organ transplantation. The objective of this study was to identify the impact of these molecules on transplant success or failure.MethodsA systematic review of literature was performed with the use of MeSH terms in Pubmed. Clinical trials, randomized clinical trials, case-control studies, and reviews from the past 15 years were included.ResultsHLA-E*0103/E*0103 genotype is associated with lower risk of graft-versus-host disease, decreased mortality, and greater disease-free survival after bone marrow transplantation. There were no significant associations between HLA-F and clinical outcomes in any of the studies. Elevated serum levels of HLA-G were associated with a lower incidence of rejection in hepatic and renal transplantation during the 1st year and lower T-cell response after bone marrow, liver, and kidney transplantation. Detection of mRNA of HLA-G1 was also associated with less graft rejection.ConclusionsCurrent literature suggests that nonclassic HLA Ib molecules play an important role in immunotolerance in organ transplantation; however, more studies are required to predict outcomes related to specific genotypes. 相似文献
106.
O. Suarez M. Pardo S. Gonzalez D.P. Escobar-Serna D.A. Castaneda D. Rodriguez J.C. Osorio E. Lozano 《Transplantation proceedings》2014,46(9):3015-3020
BackgroundNew-onset diabetes after renal transplantation (NODAT) is one of the most frequent metabolic complications after transplantation; it is present in ~25% of kidney transplant recipients, increasing their cardiovascular risk and inducing graft damage. The medical approach of this entity is still a matter of controversy, so our aim was to review the evidence available and offer a practical approach for diagnosis, treatment, and follow-up.MethodsA systematic review of the literature in the Medline, Embase, Cochrane, and Lilacs databases was carried out with the use of the terms “Diabetes Mellitus,” “Kidney Transplantation,” “Drug Therapy,” “Prognosis,” “Therapeutics,” and “Risk Factors.” Randomized controlled trials, meta-analyses, and observational studies were included.ResultsThe main risk factors were elevated body mass index, family history of diabetes, recipient >60 years old, hepatitis C virus infection, and treatment with tacrolimus/corticosteroids or sirolimus. Some small studies suggest that thiazolidinediones, sulfonylureas, glinides, and dipeptidyl peptidase 4 inhibitors could be useful in the treatment of the disease. NODAT constitutes a prognostic factor for the renal transplant. Although there is a higher risk of developing diabetes in kidney transplant recipients than in the general population, both populations share the same diagnostic criteria.ConclusionsThere is no consensus on the treatment regimen for these patients. It is necessary to review the diagnostic criteria and the screening methods for NODAT, given the higher susceptibility of kidney transplant recipients to develop this entity; therefore, an earlier intervention could be implemented to decrease the negative effects that this disease has on the kidney graft and the recipient. 相似文献
107.
Ramiro Gomez‐Villa MD Francisco Aguilar‐Rebolledo MD PhD Adriana Lozano‐Platonoff MD Juan Miguel Teran‐Soto MD Maria Rosy Fabian‐Victoriano ETN Nicole Stephanie Kresch‐Tronik MD Ximena Garrido‐Espíndola ETN Adriana Garcia‐Solis MD Augusto Bondani‐Guasti MD PhD Guillermo Bierzwinsky‐Sneider MD José Contreras‐Ruiz MD 《Wound repair and regeneration》2014,22(4):497-503
The healing process in diabetic foot ulcer (DFU) is hindered by factors such as chronic inflammation, defects in fibroblast function, poor angiogenesis, and lack of cell migration. Recombinant human epidermal growth factor (rhEGF) has been shown to enhance extracellular matrix formation, cellular proliferation, and angiogenesis. Therefore, intralesional application of rhEGF in DFU could accelerate wound healing. Our objective was to determine the efficacy and safety of rhEGF in patients with DFU. A randomized, double‐blinded, placebo‐controlled study was conducted comparing a thrice‐per‐week intralesional application of rhEGF (75 μg) or placebo in patients with DFU for 8 weeks. The number of completely healed ulcers, size, and wound bed characteristics were evaluated to determine the efficacy of rhEGF. Adverse events were recorded and analyzed to establish its safety. A total of 34 patients were recruited for the study. After three dropouts, we were able to follow and analyze 16 patients in the placebo group and 15 patients in the rhEGF study to the end of the trial. Baseline testing showed that both groups were similar. Compared to the placebo group, more ulcers achieved complete healing in the rhEGF group (rhEGF, n = 4; placebo, n = 0; p = 0.033); ulcers in the rhEGF group decreased in area size (12.5 cm2 [rhEGF] vs. 5.2 cm2 [placebo]; p = 0.049); and more epithelial islands in the wound bed were present (28% vs. 3%; p = 0.025). Mild transitory dizziness was the only side effect that was more frequently noted in the rhEGF group. Our results showed that in patients with DFU who received standard care, intralesional rhEGF application resulted in complete healing in more patients, promoted the epithelialization of the wound bed, and significantly reduced the area of the DFU treated. Therefore, rhEGF resulted in better outcomes for patients suffering from DFU. 相似文献
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