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51.
Cancer is a complex disease and unfortunately understanding how the components of the cancer system work does not help understand the behavior of the system as a whole. In the words of the Greek philosopher Aristotle “the whole is greater than the sum of parts.” To date, thanks to improved information technology infrastructures, it is possible to store data from each single cancer patient, including clinical data, medical images, laboratory tests, and pathological and genomic information. Indeed, medical archive storage constitutes approximately one-third of total global storage demand and a large part of the data are in the form of medical images. The opportunity is now to draw insight on the whole to the benefit of each individual patient. In the oncologic patient, big data analysis is at the beginning but several useful applications can be envisaged including development of imaging biomarkers to predict disease outcome, assessing the risk of X-ray dose exposure or of renal damage following the administration of contrast agents, and tracking and optimizing patient workflow. The aim of this review is to present current evidence of how big data derived from medical images may impact on the diagnostic pathway of the oncologic patient.  相似文献   
52.
We investigated the relationship of locus of control and life events to outcome of treatment at 6 months in 67 patients with alcohol dependence. Outcome was less favourable in patients with pre-treatment scores indicating external locus of control than in those with internal locus of control. Furthermore, patients with relapse in the follow-up period experienced more independent life events with moderate to severe objective negative impact than those with more favourable outcome. These results suggest that locus of control may be of clinical use in formulating treatment and prognosis, and that the occurrence of life events may influence outcome. The results are discussed in relation to strategies for treatment and prevention of relapse.  相似文献   
53.
Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) are currently used alone or in combination for therapeutic applications especially for bone repair. We tested whether MSCs can be isolated from bone marrow (BM) aspirate using a commercially available kit commonly used to obtain PRP from peripheral blood (PB). Results revealed that mononuclear cells and platelets from both PB and BM could be efficiently isolated by obtaining a mononuclear and platelet rich fraction (PB‐MPRF and BM‐MPRF, respectively). Starting with comparable volumes, the number of platelets increased 1.5‐fold in BM‐MPRF compared to PB‐MPRF. The number of clonogenic cells in BM‐MPRF samples was significantly higher than whole BM samples as revealed by CFU‐F assay (54.92 ± 8.55 CFU‐F/1.5 x 105 nucleated cells and 32.50 ± 12.43 CFU‐F/1.5 x 105 nucleated cells, respectively). Cells isolated from BM‐MPRF after in vitro expansion fulfilled the definition of MSCs by phenotypic criteria, and differentiated along osteogenic, adipogenic and chondrogenic lineages following induction. Results showed that the kit isolated MSCs and platelets from BM aspirate. Isolated MSCs were further expanded in a laboratory and BM‐MPRF was used clinically following BM withdrawal for rapid intra‐operative cell therapy for the treatment of bone defects. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
54.
Phase-contrast imaging is one of the most important emerging x-ray imaging techniques. In this work we analyse, from a theoretical point of view, the in-line phase-contrast image formation under general assumptions. The approach is based on wave-optical theory (Fresnel/Kirchoff diffraction integrals) and on the formalism of the mutual coherence function for the evolution of the coherence wavefield properties. Our theoretical model can be applied to phase-contrast imaging realized both by using highly coherent synchrotron radiation and micro-focus x-ray laboratory sources. Thus, the model is suitable for widespread applications, ranging from material science to medical imaging of human body parts. However, it cannot be applied to polychromatic sources, although the validity of the model does not require particularly demanding characteristics of monochromaticity. In addition, for moderate phase gradients, a useful analytical formula of the phase-contrast visibility is derived, based on the a priori knowledge of source size and distance, pixel detector size, defocus distance, material/tissue dielectric susceptibility and characteristic scales of transversal and longitudinal non-uniformities of the material/tissue dielectric susceptibility. Comparisons both with experimental results published by other authors and with simulations based on a Fourier optics approach have been reported, to confirm the validity of the proposed analytical formula  相似文献   
55.
PURPOSE: Serum levels of angiogenic cytokines decrease after radiotherapy in patients with cancer, and this may be relevant for treatment response and progression-free survival. Herein, we set out to determine whether circulating fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF) and platelet-derived growth factor-beta (PDGF-beta) decrease after radiotherapy in patients with non-Hodgkin lymphomas (NHLs) and if so, whether their decrease correlates with age, tumour histotype and stage, and radiation dose. MATERIAL AND METHODS: The serum levels of FGF-2, VEGF, HGF and PDGF-beta were evaluated before and after radiotherapy by an enzyme-linked immunosorbent assay (ELISA). These levels were correlated both reciprocally and with age, histotype, stage and radiation dose. RESULTS: After radiotherapy, FGF-2, VEGF and PDGF-beta, but not HGF, significantly decreased in relation to the radiation dose and response. No correlation was established between cytokine levels, except for VEGF and PDGF-beta, which decreased in parallel. Haemoglobin levels did not decrease after radiotherapy, while FGF-2, VEGF, HGF and PDGF-beta levels did not correlate with age, NHL stage and histotype. CONCLUSIONS: Soluble FGF-2, VEGF and PDGF-beta levels decline after radiotherapy in NHLs, and may have predictive significance for response to treatment and recurrence.  相似文献   
56.
Motor imagery (MI) is the ability to imagine performing a movement without executing it. In literature, there have been numerous reports on the influence of MI on motor practice and the beneficial effects of “mental practice” on the physical performance has been suggested to rely to the close temporal association between motor rehearsal and actual performance. In the present study, we aimed to evaluate whether the addition of a period of motor imagery between two motor practice trials could modify movement execution in a repetitive finger opposition motor task performed at maximal speed and whether the effect of motor imagery on motor practice is dependant on the complexity of movement. We observed that the addition of motor imagery to the sole motor practice was able to influence the performance of repetitive finger opposition movements inducing an increase of the velocity of movement greater than that observed with the motor practice alone. Further the addition of motor imagery was able to induce a modification in the motor strategy in terms of duration of the main phases of movements. This was more evident when subjects executed a finger sequential task with respect to a simple finger tapping task. We assume that mental rehearsal facilitates the brain network involved in sensorimotor control, particularly acting on those neural structures involved in the motor program.  相似文献   
57.

Purpose

To investigate the effect of creatine (CR) supplementation on the acute interference induced by aerobic exercise on subsequent maximum dynamic strength (1RM) and strength endurance (SE, total number of repetitions) performance.

Methods

Thirty-two recreationally strength-trained men were submitted to a graded exercise test to determine maximal oxygen consumption (VO2max: 41.56 ± 5.24 ml kg?1 min?1), anaerobic threshold velocity (ATv: 8.3 ± 1.18 km h?1), and baseline performance (control) on the 1RM and SE (4 × 80 % 1RM to failure) tests. After the control tests, participants were randomly assigned to either a CR (20 g day?1 for 7 days followed by 5 g day?1 throughout the study) or a placebo (PL-dextrose) group, and then completed 4 experimental sessions, consisting of a 5-km run on a treadmill either continuously (90 % ATv) or intermittently (1:1 min at vVO2max) followed by either a leg- or bench-press SE/1RM test.

Results

CR was able to maintain the leg-press SE performance after the intermittent aerobic exercise when compared with C (p > 0.05). On the other hand, the PL group showed a significant decrease in leg-press SE (p ≤ 0.05). CR supplementation significantly increased bench-press SE after both aerobic exercise modes, while the bench-press SE was not affected by either mode of aerobic exercise in the PL group. Although small increases in 1RM were observed after either continuous (bench press and leg press) or intermittent (bench press) aerobic exercise in the CR group, they were within the range of variability of the measurement. The PL group only maintained their 1RM.

Conclusions

In conclusion, the acute interference effect on strength performance observed in concurrent exercise may be counteracted by CR supplementation.  相似文献   
58.
59.
Silk fibroin (SF) obtained from Bombyx mori cocoon is a very promising biopolymer. It can be processed from aqueous solutions to obtain many versatile scaffolds useful in optoelectronics, photonics, and biomedicine. Aqueous solutions are prepared by dissolving degummed fibroin with chaotropic agents and then purifying by dialysis. This work presents, for the first time, a solubilization protocol, involving CeCl3·7H2O as chaotropic salt in water and ethanol, that allows to regenerate SF under a fibrous form, unlike the standard Ajisawa’s method, which uses CaCl2 and allows to obtain aqueous gels. All the experimental analyses performed (SEM, XPS, WAXS, ATR‐FTIR, NMR) suggest that the fiber recovered preserves most of the morphological and structural features of the pristine SF and is doped with Ce(III) ions, that interact mainly with the oxygen atoms of C?O moieties and side‐chains of amino acids. Ce(III) doped SF could be the base for new luminescent materials.  相似文献   
60.
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