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141.
Giancarlo Colombo Carla Lobina Paola Maccioni M Francesca Mascia Alessandro Orrù Gian Luigi Gessa Mauro A M Carai 《Alcohol》2005,35(1):35-41
In the current study, we investigated the effect of the concurrent presentation of saccharin on the maintenance of alcohol-drinking behavior in selectively bred Sardinian alcohol-preferring (sP) rats. Rats were initially given access to alcohol [10% (volume/volume) in water] and water under the home cage, two-bottle, free-choice regimen, with unlimited access for 24 h/day for eight consecutive weeks. Next, a third bottle, containing saccharin [0%, 0.01%, 0.1%, 1%, or 3% (weight/volume) in water], was concomitantly offered for an additional 10 consecutive days. Intake of saccharin solution resulted as an inverted-U function of saccharin concentration, with the 0.1% saccharin solution being the highest accepted. Alcohol intake was a U function of saccharin concentration, being reduced by 65%-95% in the group of rats exposed to the 0.1% saccharin solution. These results indicate that (1) the concurrent presentation of highly palatable solutions of saccharin markedly reduced alcohol intake in alcohol-experienced sP rats and (2) the reducing effect of saccharin solutions on the alcohol intake in sP rats was positively related to their degree of acceptability. We hypothesized that saccharin solutions may have functioned as a reinforcer, partially substituting for alcohol reinforcement and rendering alcohol drinking less urgent. 相似文献
142.
Vascular endothelial growth factor and basic fibroblast growth factor in polycystic ovary syndrome during controlled ovarian hyperstimulation. 总被引:4,自引:0,他引:4
Paolo Giovanni Artini Massimiliano Monti Cristiana Matteucci Valeria Valentino Francesca Cristello Andrea Riccardo Genazzani 《Gynecological endocrinology》2006,22(8):465-470
BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disorder that causes anovulation and consequent subfertility. It is well established that increased ovarian mass, supported by new blood vessel proliferation in stroma and theca, is a key feature of PCOS. Recent studies suggest a role for angiogenetic factors in this phenomenon. AIM: To evaluate of levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in serum and follicular fluid of PCOS patients during a controlled ovarian hyperstimulation. METHODS: In 52 patients undergoing in vitro fertilization treatments, 26 PCOS patients and 26 controls, serum VEGF and bFGF levels were assessed before starting administration of follicle-stimulating hormone (FSH) (day 0), on the day of administration of human chorionic gonadotropin (hCG) and on the day of oocyte retrieval. Follicular fluid levels of the two growth factors were detected on the day of oocyte retrieval. RESULTS: PCOS patients showed higher serum VEGF levels than controls before starting FSH administration, on the day of hCG administration and on the day of oocyte retrieval. Serum VEGF levels showed a rise after hCG administration only in the PCOS patients. In addition, serum bFGF levels were higher in PCOS patients than in controls on the day of hCG administration and the day of oocyte retrieval. Furthermore, on the day of hCG administration, serum bFGF levels were directly correlated to the amount of FSH previously administered (p < 0.0001). In follicular fluid, higher VEGF and bFGF levels were found in PCOS patients than in controls. Furthermore, follicular-fluid bFGF concentrations were inversely correlated with the percentage of mature oocytes collected (p < 0.05). CONCLUSIONS: The present study revealed elevated levels of VEGF and bFGF in serum and follicular fluid in PCOS patients compared with controls. bFGF seems to be an FSH-dependent growth factor and its levels in follicular fluid are inversely correlated with the percentage of mature oocytes collected. 相似文献
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145.
Ludmylla Cunha Ana M. Rosa da Costa João P. Lourenço Francesca Buttini 《Journal of microencapsulation》2018,35(4):392-405
Pulmonary tuberculosis accounts for 80% of cases and the delivery of antitubercular drugs into the lungs allows targeting the infected organ and, possibly, reducing systemic drug toxicity. This work aimed at using fucoidan as matrix of inhalable microparticles that associate two first-line antitubercular drugs, for an application in pulmonary tuberculosis therapy. Fucoidan is composed of fucose and sulphated sugar residues, moieties described as being recognised by surface receptors of alveolar macrophages, which host mycobacteria. Inhalable fucoidan microparticles loaded with antitubercular drugs were successfully produced with high association efficiencies of either isoniazid (95%) or rifabutin (81%). The microparticles evidenced no cytotoxicity on lung epithelial cells (A549). However, rifabutin-loaded microparticles showed a certain degree of toxicity on macrophage-like cells (THP-1) at the highest tested concentration (1?mg/mL). Furthermore, microparticles showed favourable aerodynamic properties for deep lung delivery (MMAD 2.0–3.8?µm) and, thus, show potential for an application as inhalable tuberculosis therapy. 相似文献
146.
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148.
Ivana d’Angelo Olimpia Oliviero Francesca Ungaro Fabiana Quaglia Paolo Antonio Netti 《Acta biomaterialia》2013,9(7):7389-7398
New vessel formation is the result of the complex orchestration of various elements, such as cells, signalling molecules and extracellular matrix (ECM). In order to establish the suitable conditions for an effective cell response, the influence of vascular endothelial growth factor (VEGF) complexation with heparin sodium salt (Hp) on its pro-angiogenic activity has been evaluated by an in vitro capillary-like tube formation assay. VEGF with or without Hp was embedded into collagen gels, and the activated matrices were characterized in terms of VEGF activity and release kinetics. Taking into account the crucial role of Hp in VEGF stability and activity, VEGF/Hp complex was then encapsulated into microspheres based on poly(lactide-co-glycolide) (PLGA), and microsphere properties, VEGF/Hp release kinetics and VEGF in vitro activity over time were evaluated. Integrated microsphere/collagen matrices were developed in order to provide a continuous release of active VEGF/Hp inside the matrix but also a VEGF gradient at the boundary, which is an essential condition for endothelial cell attraction and scaffold invasion. The results confirmed a strong influence of Hp on VEGF configuration and, consequently, on its activity, while the encapsulation of VEGF/Hp complex in PLGA-microspheres guaranteed a sustained release of active VEGF for more than 30 days. This paper confirms the importance of VEGF stability and signal presentation to cells for an effective proangiogenic activity and highlights how the combination of two stabilizing approaches, namely VEGF/Hp complexation and entrapment within PLGA-based microspheres, may be a very effective strategy to achieve this goal. 相似文献
149.
Guy N.J. Betts Amanda Eustace Shalini Patiar Helen R. Valentine Joely Irlam Anassuya Ramachandran Ashirwad Merve Jarrod J. Homer Carla Möller-Levet Francesca M. Buffa Gillian Hall Crispin J. Miller Adrian L. Harris Catharine M.L. West 《European journal of cancer (Oxford, England : 1990)》2013,49(1):156-165
Background and purposeTumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours.Materials and methodsTumour samples (n = 201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV).ResultsThe assay was sensitive with linear reaction efficiencies across a 4log10 range of inputted cDNA (0.001–10 ng/μl). Intra- (CoV = 6.9%) and inter- (CoV = 2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO2. TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p < 0.01) and positive pimonidazole scores (p = 0.005).ConclusionsGene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material. 相似文献
150.
In the last decades, international guidelines proposed different strategies of complementary foods introduction during weaning to prevent allergy. Avoidance measures, such as late introduction of allergenic foods, failed to show a significant preventive effect towards allergy. Recently, prospective randomized controlled studies suggested that the early introduction of solid foods ‐ rather than the late introduction ‐ could be a strategy to prevent allergic sensitization and food allergy. However, at today clear evidence of effectiveness and safety of early introduction are not yet available to recommend a radical change in the current clinical practice. A realistic advice for the general population could be to begin the weaning at 4–5 months with the progressive introduction of different foods. The advices for introduction of solid foods during weaning should also take in consideration the global development of child to chose the better timing of introduction of foods. 相似文献