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991.
A 2.5-year-old girl presented with koilonychia since birth and was subsequently found to have dome-shaped femoral epiphyses and platyspondylia with anterior central tongues on a skeletal survey. 相似文献
992.
Exercise-induced gene expression changes in the rat spinal cord 总被引:2,自引:0,他引:2
There is growing evidence that exercise benefits recovery of neuromuscular function from spinal cord injury (SCI). However, the effect of exercise on gene expression in the spinal cord is poorly understood. We used oligonucleotide microarrays to compare thoracic and lumbar regions of spinal cord of either exercising (voluntary wheel running for 21 days) or sedentary rats. The expression data were filtered using statistical tests for significance, and K-means clustering was then used to segregate lists of significantly changed genes into sets based upon expression patterns across all experimental groups. Levels of brain-derived neurotrophic factor (BDNF) protein were also measured after voluntary exercise, across different regions of the spinal cord. BDNF mRNA increased with voluntary exercise, as has been previously shown for other forms of exercise, contributed to by increases in both exon I and exon III. The exercise-induced gene expression changes identified by microarray analysis are consistent with increases in pathways promoting neuronal health, signaling, remodeling, cellular transport, and development of oligodendrocytes. Taken together these data suggest cellular pathways through which exercise may promote recovery in the SCI population. 相似文献
993.
Two Leonardo projects, EMERALD and EMIT, have developed in a partnershipof university and hospital departments (the consortia) e-Learning materials in X-ray diagnostic radiology, nuclear medicine, radiotherapy, ultrasound and magnetic resonance imaging for medical physics graduates and other healthcare professionals. These e-Learning materials are described in a separate paper in this issue. To assess the effectiveness and relevance of the e-Learning material, a series of evaluations by student users groups plus experts in medical physics education and training were undertaken. The students, with backgrounds in physics and clinical ultrasound, reviewed the e-Learning material using an evaluation form developed by the consortia. The student feedback was favourable with students commenting that their level of knowledge had increased having completed the tasks. Areas identified for development were a reduction in text volume and an increase in the time allowed for completion of some tasks. The feedback from the experts was positive with an overall appreciation of the value of the learning material as a resource for students in medical physics field across Europe and identified other disciplines in which the access to the learning material could be useful contribution to their learning. Suggestions made for improvements ranged from grading the tasks into basic and advanced topics to increasing the interactive nature of the material. These early evaluation of the e-Learning material look promising and provide a framework for further developments in the field. Insight into users and providers views is important if developers are to provide relevant and worthwhile educational learning opportunities. 相似文献
994.
Victoria L. Finkenstadt Julious L. Willett 《Macromolecular chemistry and physics.》2005,206(16):1648-1652
Summary: The effects of monomer/starch feed ratios and moisture content during reactive extrusion of starch‐polyacrylamide graft copolymers were investigated. Acrylamide/starch ratios ranged from 0.20 to 1.87 at 50% moisture content, while moisture content was increased from 45 to 75% with an acrylamide/starch ratio of 0.33. Average conversion was 86.6% (±3.5%), independent of monomer content, at acrylamide/starch ratios of 0.77 and less. Conversion increased to approximately 95% when the acrylamide/starch ratio exceeded unity. Molecular weight of grafted polyacrylamide increased as the acrylamide/starch ratio increased. Graft efficiency was constant at approximately 75% for monomer/starch ratios of 0.77 or less, and decreased to 52.3% as the monomer/starch ratio increased to 1.87. Higher acrylamide/starch ratios gave more frequent grafts of higher molecular weight. As moisture content decreased from 75 to 45%, conversion and graft content increased from 78 and 14% to 97 and 23%, respectively. Lower moisture content gave fewer grafts of higher molecular weight. Ungrafted polyacrylamide homopolymer increased with monomer/starch ratio and moisture content. These results indicate that graft copolymer properties can be controlled through the monomer/starch ratio and moisture content during reactive extrusion.
995.
Broiler breeders are subjected to quantitative food restriction in order to control their growth, and this restriction is particularly severe during rearing. While such restriction improves some welfare problems associated with ad libitum feeding, it causes others: birds routinely show abnormal oral behaviours and have elevated plasma corticosterone concentration (PCC) and changes in white blood cell counts (WBCs). The aim of this study was to examine if feeding birds qualitatively restricted diets ad libitum during rearing could reduce signs of impaired welfare, as judged by behaviour and blood indices of stress, while also meeting commercially desired growth rates and uniformity. Furthermore, we examined what carry-over effects such a feeding method had on birds in the laying phase when all birds were fed on a conventional quantitative restriction regime. During rearing (1-20 weeks of age), pens of birds were either fed limited amounts of standard basal diets (Control, i.e. quantitative restriction), or ad libitum diets consisting of standard basal diets with gradually increasing levels of calcium propionate (CaP) and a constant level of oat hulls (OH), designated CaP + OH (i.e. qualitative restriction). Results showed that, during rearing, weights and weight uniformity were similar for the two groups. During feeding motivation tests, Control birds always consumed more food than CaP + OH birds. This suggests that Control birds were more highly motivated to feed than CaP + OH birds, although care has to be taken in interpreting these results. Treatment did not affect PCCs or WBCs, but there was a general decline in PCCs with bird age. All reported behaviours differed significantly between treatment groups during rearing, but disappeared during lay when all birds were fed a similar amount of food. Control birds spent up to 50% of time in object pecking during rearing periods, but this behaviour was virtually non-existent in birds in the qualitative feeding regime. Overall, the results indicate that broiler breeders can be successfully limited in growth rates by qualitative food restriction and this results in significant changes of behaviour that suggest improvements to bird welfare. 相似文献
996.
This study examined whether neuroticism was related to the antibody response to influenza vaccination and whether the relationship was mediated by cortisol reactions to acute laboratory mental stress. Antibody status was assessed at baseline and to a trivalent influenza vaccination in 57 students at 5-week and 5-month follow-up. Neuroticism was also measured at baseline. Cortisol was measured at rest and in response to a pressurized mental arithmetic task. At both follow-ups, higher neuroticism scores were associated with poorer A/Panama antibody response, following adjustment for baseline antibody titer. Higher neuroticism scores were also associated with blunted cortisol reactivity, and blunted cortisol reactivity was associated with poorer A/Panama antibody response, but only at 5 months. However, there was no conclusive evidence that cortisol reactivity mediated the association between neuroticism and antibody response. 相似文献
997.
Lee AC Buckley MJ Pegman SJ Spiers H Scahill VL Gaffan D Bussey TJ Davies RR Kapur N Hodges JR Graham KS 《Hippocampus》2005,15(6):782-797
There has been considerable debate as to whether the hippocampus and perirhinal cortex may subserve both memory and perception. We administered a series of oddity tasks, in which subjects selected the odd stimulus from a visual array, to amnesic patients with either selective hippocampal damage (HC group) or more extensive medial temporal damage, including the perirhinal cortex (MTL group). All patients performed normally when the stimuli could be discriminated using simple visual features, even if faces or complex virtual reality scenes were presented. Both patient groups were, however, severely impaired at scene discrimination when a significant demand was placed on processing spatial information across viewpoint independent representations, while only the MTL group showed a significant deficit in oddity judgments of faces and objects when object viewpoint independent perception was emphasized. These observations provide compelling evidence that the human hippocampus and perirhinal cortex are critical to processes beyond long-term declarative memory and may subserve spatial and object perception, respectively. 相似文献
998.
999.
Mohr DC Burke H Beckner V Merluzzi N 《Multiple sclerosis (Houndmills, Basingstoke, England)》2005,11(2):222-226
OBJECTIVE: Peer-support interventions have shown no statistically significant or clinically meaningful effect on quality of life (QOL) or depressive symptoms for multiple sclerosis (MS) patients. Peer-support interventions for MS generally provide support but no skills training. The aim of this study was to evaluate a brief telephone-administered skills-training model of peer-support for patients with MS. METHODS: Sixteen patients with MS showing signs of moderate distress received eight sessions of telephone-administered peer support (TAPS). TAPS is a manualized programme administered by peer-support counsellors diagnosed with MS. Using a workbook, peer-support counsellors teach skills to manage distress and MS symptoms. Subjective depression was assessed using the Center for Epidemiological Studies Depression Scale while objective depression was rated using the Hamilton Rating Scale for Depression. QOL was measured pre- and post-treatment using the SF-36. RESULTS: The participants showed significant improvements on both the CESD (p = 0.04) and the HRSD (p = 0.01). Overall QOL improved significantly (p = 0.045), however this was not reflected in either the Physical Health composite score or the Mental Health Composite Scale (p > 0.17). CONCLUSIONS: These findings suggest that TAPS may prove to be an efficacious peer-support model for patients with MS. 相似文献
1000.