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991.
992.
Electrospun nanofiber drug delivery systems have been studied using various techniques. Herein, we describe the fabrication of a drug-incorporating nanofiber. Drugs, such as proteins, peptide, antibodies, and small molecule drugs, can be loaded within or on the surface of nanofibers according to their properties. Hydrophobic drugs are directly dissolved with a polymer in an organic solvent before electrospinning. However, it is preferred to surface-immobilize bioactive molecules on nanofibers by physical absorption or chemical conjugation. Especially, chemically surface-immobilized proteins on a nanofiber mesh stimulate cell differentiation and proliferation. Using a dual electrospinning nozzle to create nanofiber sheet layers, which are stacked on top of one another, the initial burst release is reduced compared with solid nanofibers because of the layers. Furthermore, hybridization of electrospun nanofibers with nanoparticles, microspheres, and hydrogels is indirect drug loading method into the nanofibers. It is also possible to produce multi-drug delivery systems with timed programmed release. 相似文献
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994.
995.
Interaction of citrate‐coated silver nanoparticles with earthworm coelomic fluid and related cytotoxicity in Eisenia andrei 下载免费PDF全文
Jin Il Kwak Woo‐Mi Lee Shin Woong Kim Youn‐Joo An 《Journal of applied toxicology : JAT》2014,34(11):1145-1154
Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate‐coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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997.
Low‐Dose Aspirin Ameliorated Hyperlipidemia,Adhesion Molecule,and Chemokine Production Induced by High‐Fat Diet in Sprague‐Dawley Rats 下载免费PDF全文
Hui‐Li Lin Hsueh‐Wei Yen Su‐Ling Hsieh Li‐Mei An Kuo‐Ping Shen 《Drug development research》2014,75(2):97-106
Preclinical Research |
998.
Wu-jie Bu Lei Song Dan-yi Zhao Bing Guo Jing Liu 《British journal of clinical pharmacology》2014,78(2):301-309
Aims
Several epidemiological studies have reported inconsistent associations between insulin therapy and the risk of colorectal cancer (CRC) in patients with type 2 diabetes mellitus. We performed this meta-analysis of observational studies to evaluate the effect of insulin therapy on the risk of CRC.Methods
We carried out a systematic search of PubMed, Embase and the Cochrane Library Central database between January 1966 and August 2013. Fixed-effects and random-effects models were used to estimate the pooled relative risk (RR) and corresponding 95% confidence interval (CI).Results
A total of 12 epidemiological studies were included in the present meta-analysis, involving a total of 7947 CRC cases and 491 384 participants. There was significant heterogeneity among the studies, but no publication bias. Insulin therapy significantly increased the risk of CRC [RR = 1.69, 95% CI (1.25, 2.27)]. When the various studies were stratified by study design, we found that insulin use was associated with a statistically significant 115% higher risk of CRC among case–control studies [RR = 2.15, 95% CI (1.41, 3.26)], but not among cohort studies [RR = 1.25, 95% CI (0.95, 1.65)]. Furthermore, a significant association was noted among studies conducted in USA [RR = 1.73, 95% CI (1.15, 2.60)] and Asia [RR = 2.55, 95% CI (2.14, 3.04)], but not in Europe [RR = 1.20, 95% CI (0.92, 1.57)].Conclusions
The present meta-analysis suggests that insulin therapy may increase the risk of CRC. More prospective cohort studies with longer follow-up durations are warranted to confirm this association. Furthermore, future studies should report results stratified by gender and race and should adjust the results by more confounders. 相似文献999.
Min-Hyo Ki Ji-Eon Kim Young-Nam Lee Sang Myoung Noh Sung-Won An Hyun-Jong Cho Dae-Duk Kim 《Pharmaceutical research》2014,31(12):3323-3334
Purpose
Chitosan, a natural and biocompatible cationic polymer, is an attractive carrier for small interfering RNA (siRNA) delivery. The purpose of this study was to develop a chitosan-based hybrid nanocomplex that exhibits enhanced physical stability in the bloodstream compared with conventional chitosan complexes. Hybrid nanocomplexes composed of chitosan, protamine, lecithin, and thiamine pyrophosphate were prepared for systemic delivery of survivin (SVN) siRNA.Methods
Physicochemical properties of the nanoparticles including mean diameters and zeta potentials were characterized, and target gene silencing and cellular uptake efficiencies of the siRNA nanocomplexes in prostate cancer cells (PC-3 cells) were measured. In vivo tumor targetability and anti-tumor efficacy by systemic administration were assessed in a PC-3 tumor xenograft mouse model by near-infrared fluorescence (NIRF) imaging and tumor growth monitoring, respectively.Results
Mean diameters of the SVN siRNA-loaded hybrid nanocomplex (GP-L-CT) were less than 200 nm with a positive zeta potential value in water and were maintained without aggregation in culture media and 50% fetal bovine serum. SVN expression in PC-3 cells was reduced to 21.9% after treating with GP-L-CT. The tumor targetability and growth inhibitory efficacies of GP-L-CT supported the use of this novel hybrid nanocomplex as a cancer therapeutic and as a theranostic system for systemic administration.Conclusions
A chitosan-based hybrid nanocomplex was successfully developed for the systemic delivery of SVN siRNA, which could serve as an alternative to cationic polymeric nanoparticles that are unstable in serum. 相似文献1000.
Irena Loryan Vikash Sinha Claire Mackie Achiel Van Peer Wilhelmus Drinkenburg An Vermeulen Denise Morrison Mario Monshouwer Donald Heald Margareta Hammarlund-Udenaes 《Pharmaceutical research》2014,31(8):2203-2219