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991.
Ernst RK Moskowitz SM Emerson JC Kraig GM Adams KN Harvey MD Ramsey B Speert DP Burns JL Miller SI 《The Journal of infectious diseases》2007,196(7):1088-1092
Three structural features of lipid A (addition of palmitate [C16 fatty acid], addition of aminoarabinose [positively charged amino sugar residue], and retention of 3-hydroxydecanoate [3-OH C10 fatty acid]) were determined for Pseudomonas aeruginosa isolates from patients with cystic fibrosis (CF; n=86), from the environment (n=13), and from patients with other conditions (n=14). Among P. aeruginosa CF isolates, 100% had lipid A with palmitate, 24.6% with aminoarabinose, and 33.3% retained 3-hydroxydecanoate. None of the isolates from the environment or from patients with other conditions displayed these modifications. These results indicate that unique lipid A modifications occur in clinical P. aeruginosa CF isolates. 相似文献
992.
Wolinsky H 《Journal of the American College of Cardiology》2007,50(19):1911; author reply 1911
993.
Interactive effects of C3, cyclic AMP and ciliary neurotrophic factor on adult retinal ganglion cell survival and axonal regeneration 总被引:1,自引:0,他引:1
We tested whether combined therapy involving Rho inactivation, elevation of cAMP and supply of ciliary neurotrophic factor (CNTF) (i) increased axotomized adult retinal ganglion cell (RGC) survival and (ii) promoted axonal regeneration into peripheral nerve (PN) autografted onto the cut optic nerve. PN-grafted eyes were injected with combinations of a Rho-inactivating enzyme C3 transferase (C3-11), CNTF and a cell-permeant analogue of cAMP (CPT-cAMP). Four weeks after PN transplantation, RGC survival was quantified using beta-III tubulin immunohistochemistry. Regeneration was assessed using retrograde fluorogold tracing and pan-neurofilament immunostaining of grafts. Treatment with C3-11 increased RGC survival but co-injection with CPT-cAMP, CNTF or combined CNTF/CPT-cAMP did not further enhance RGC viability. There were greater numbers of regenerating RGCs after multiple C3-11 injections and regeneration was further and significantly increased after intravitreal injections of all three factors. In the combined C3-11/CNTF/CPT-cAMP treatment group about 15% of RGCs remained viable of which more than half regenerated an axon. These data emphasize the power of combinatorial pharmacotherapeutic and transplant strategies in the treatment of neurotrauma. 相似文献
994.
Anhedonia, the reduced capacity to gain pleasure from pleasurable experiences, is a key symptom of major depression and schizophrenia. Reduced hedonic capacity can also be measured as an enduring trait in non-clinical subjects. Such altered hedonic capacity is likely the result of a basic neuropsychophysiological dysfunction and a vulnerability marker that potentially precedes and contributes to the liability of developing psychiatric disorders. The characterization of the structural and functional neural correlates of trait anhedonia in non-clinical individuals may provide new insights for the early detection of such psychiatric diseases. Twenty-nine non-clinical subjects were scanned at the Montreal Neurological Institute. Trait anhedonia was measured using the Chapman Revised Physical Anhedonia Scale. Semi-automated and automated structural MRI segmentation techniques were used to explore structural correlates of trait anhedonia. Seventeen of the 29 subjects also underwent a functional imaging task where responses to the viewing of affective stimuli were examined to identify the functional correlates of trait anhedonia. Trait anhedonia was inversely related to anterior caudate volume, but positively related to ventromedial prefrontal cortex activity during the processing of positive information. These findings may reflect a specific kind of vulnerability for the development of psychiatric affective disorders and suggest that trait anhedonia may be linked to a volumetric reduction in the basal ganglia and to a prefrontal functional abnormality during hedonic processing. 相似文献
995.
996.
997.
PURPOSE: To improve the immunity of the proton resonance frequency shift (PRFS) method of MRI temperature mapping against magnetic field disturbances. Since PRFS is a phase-sensitive method, it misinterprets magnetic field disturbances as artifact temperature changes. If not corrected, the resulting temperature artifacts can completely obscure the true temperature estimation, especially if the temperature elevations are small. MATERIALS AND METHODS: Since the fat protons experience the same magnetic field disturbances as the water protons, but no temperature-related frequency shift, the fat signal has been used for correcting PRFS temperature maps for the disturbances. A simple correction method is proposed that has either better compensation capability than the phase correction methods previously reported or higher spatial and temporal resolution than the spectroscopic correction methods previously reported. The evaluated method is based on the utilization of several gradient and spin echoes acquired within one repetition interval with water- and fat-selective scans. RESULTS: In a series of phantom experiments, the improved method is shown to enable the reconstruction of accurate temperature maps in spite of interscan motion, suboptimal fat-water separation, and a wide range of magnetic field disturbances. CONCLUSION: Our approach can be used for the guidance of thermal therapies involving tissues containing fat or surrounded by fat. 相似文献
998.
Holloway R Zhou Z Harvey HB Levasseur JE Rice AC Sun D Hamm RJ Bullock MR 《Acta neurochirurgica》2007,149(9):919-927
Summary
Background. In previous studies, it has been shown that intravenous lactate therapy can improve brain neurochemistry, adenosine triphosphate
(ATP) generation and outcome after traumatic brain injury (TBI) in rats. In this study, we examined: (1) four L-lactate concentrations
to determine the optimal therapeutic dose post TBI in terms of cognitive function; (2) ATP production after TBI for the L-lactate
concentration found to be the optimal dose; (3) the possible production of lactic acidosis with the highest L-lactate concentration
tested.
Methods. Thirty minutes following a fluid percussion injury (FPI) over the left cerebral hemisphere, the animals received an intravenous
infusion of 10, 28, 100, or 280 mM L-lactate (n = 10 for each group) for 3 h at a rate of 0.65 ml/h. Shams and control injured animals received a saline infusion. At 11–15
days post injury, cognitive deficits were examined using the Morris Water Maze (MWM) test. Three groups of rats were used
for ATP analysis: shams, injured + saline infusion, and injury + the optimal lactate dose as determined by the MWM (n = 4/group). Additionally, a group receiving 280 mM L-lactate (n = 5) and one receiving a saline infusion (n = 3) were monitored for arterial blood variables and blood pressures.
Findings. In the MWM test, only the 100 mM L-lactate-treated injured animals showed a significant reduction in cognitive deficits
when compared to saline-treated injured animals (p ≤ 0.05). In the ATP study, injured animals without treatment had a 53% reduction in ATP level in the ipsilateral cortex,
while animals with 100 mM lactate treatment had a 28% reduction. (p ≤ 0.05). No lactic acidosis was induced by the intravenous infusion of 280 mM L-lactate.
Conclusions. This study indicates that the intravenous infusion of 100 mM L-lactate provided the optimal concentration of the substrate
to ameliorate cognitive impairment, probably via the regeneration of ATP following TBI in rats. 相似文献
999.
1000.
Livdans-Forret AB Harvey PJ Larkin-Thier SM 《The Journal of the Canadian Chiropractic Association》2007,51(4):235-246