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71.
《Mayo Clinic proceedings. Mayo Clinic》2022,97(8):1525-1533
The importance of the left atrial appendage (LAA) as the source of thromboembolism including stroke in patients with nonvalvular atrial fibrillation is well documented, with more than 90% of ischemic strokes related to a LAA thrombus. Although oral anticoagulation has been the standard of care, approximately 50% to 60% of patients either have contraindications to oral anticoagulation or do not continue the medication beyond the first year. This led to the development of local site-specific therapy to occlude the LAA by either surgical or transcatheter means. Despite marked advancements, incomplete LAA closure with surgical and transcatheter approaches remains frequent. The etiology of incomplete LAA closure and its clinical implications remain unclear. Multiple strategies are in development including changes in deployment techniques, a new device design, and alternative approaches to leak closure. 相似文献
72.
《Saudi Pharmaceutical Journal》2022,30(6):655-668
Most vaccines approved by regulatory bodies are administered via intramuscular or subcutaneous injections and have shortcomings, such as the risk of needle-associated blood infections, pain and swelling at the injection site. Orally administered vaccines are of interest, as they elicit both systemic and mucosal immunities, in which mucosal immunity would neutralize the mucosa invading pathogen before the onset of an infection. Hence, oral vaccination can eliminate the injection associated adverse effects and enhance the person's compliance. Conventional approaches to manufacturing oral vaccines, such as coacervation, spray drying, and membrane emulsification, tend to alter the structural proteins in vaccines that result from high temperature, organic and toxic solvents during production. Electrohydrodynamic processes, specifically electrospraying, could solve these challenges, as it also modulates antigen release and has a high loading efficiency. This review will highlight the mucosal immunity and biological basis of the gastrointestinal immune system, different oral vaccine delivery approaches, and the application of electrospraying in vaccines development. 相似文献
73.
Previous event-related potential (ERP) studies show that a salient lateral sound activates the visual cortex more strongly contralateral to the sound, observed as an auditory-evoked contralateral occipital positivity (ACOP). Studies showed that this activation enhances the early cortical processing of co-localized visual stimuli presented after, reflected by better detection rates, better discrimination, and sharper perceived contrast. We replicated the ACOP, using earphones, and tested whether auditory cuing can influence temporal order judgments (TOJ) for two visual stimuli (horizontal arrangement) as well as if the ACOP would predict the amplitude of this influence. A lateral salient sound was followed, after 150 or 630 ms, by the visual presentation of a pair of disks, one in left and one in right hemifield, with variable SOA. The TOJ task was to indicate which disk appeared first or which disk appeared second (controlling for response bias). We observed an ACOP at posterior electrode sites and confirmed our hypothesis that the lateral sound influenced TOJ by accelerating the perception of the disk presented on the cued side, even though the sound was irrelevant to the task. Furthermore, the ACOP amplitude was correlated to this visual perceptual change, indicating that a larger change in brain activity was associated with a faster processing of co-localized visual stimuli. 相似文献
74.
Capillary leak syndrome (CLS) is a rare clinical syndrome associated with significant morbidity and mortality. Intensive care and supportive therapy constitute the mainstay of the treatment, along with judicious use of crystalloids and colloids such as dextran and starch during the leak phase. The advantages of proning, steroids, and intravenous immunoglobins are worth contemplating in patients with such a presentation. Extracorporeal membrane oxygenation appears to be an excellent strategy to surmount the impediments of the leak and post leak phase of CLS, especially in patients with severe or refractory hypoxemia. 相似文献
75.
《Injury》2023,54(2):318-328
PurposeThis study intended to determine the properties of induced membranes after various periods of polymethyl methacrylate (PMMA) retention and the effect of different retention intervals on subsequent defect repair.MethodsModel of a critical bone defect in rabbits was prepared to obtain the induced membrane. For varying intervals of spacer insertion (2, 4, 6, 8, 12, 16, and 20 weeks postoperatively), angiogenesis, osteogenesis, and MSC-related properties were analyzed by immunohistochemistry and western-blot. Furthermore, 2, 4, 6, and 8 weeks after PMMA insertion, bone grafting was performed. Characteristics of defect repair were analyzed by X-ray and micro-CT analysis.ResultsThe induced membrane displayed angiogenesis, osteogenesis, and MSC-related properties from the 2- to 20-week intervals. Quantitation of protein expression (RUNX2, ALP, VEGF, TGF-beta, OCT4, and STRO1) revealed that selected proteins gradually rose to a high level at 4–8 weeks postoperatively and then decreased to a low level over a long time period. Following bone grafting, the most new bone formation was in the group when grafting was performed at 4 weeks, followed by the groups at 2 and 6 weeks, with the least in the group at 8 weeks.ConclusionThe induced membrane displays angiogenesis, osteogenesis, and MSC-related properties from the 2- to 20-week intervals. These were increased to a peak level at 4–8 weeks postoperatively and then gradually decreased. The optimal timing for bone grafting at the second stage in the presented model was 4 weeks after PMMA insertion. 相似文献
76.
Stephanie H. Ameis John D. Haltigan Rachael E. Lyon Amanda Sawyer Pat Mirenda Connor M. Kerns Isabel M. Smith Tracy Vaillancourt Joanne Volden Charlotte Waddell Lonnie Zwaigenbaum Teresa Bennett Eric Duku Mayada Elsabbagh Stelios Georgiades Wendy J. Ungar Anat Zaidman-Zait Meng-Chuan Lai Peter Szatmari for the Pathways in ASD Study Team 《Journal of child psychology and psychiatry, and allied disciplines》2022,63(5):553-562
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79.
Silvia Ceccanti Francesco Cozzi Alice Cervellone Augusto Zani Denis A. Cozzi 《Journal of pediatric surgery》2019,54(2):326-330
Aim
We sought to assess the magnitude of functional decline and the natural history of the operated kidney residual function after zero-ischemia nephron-sparing surgery (Z-NSS) in children with unilateral renal tumor (URT).Patients and methods
50 children were treated for URT at our surgical unit between 1992 and 2016. Of these 12 who underwent Z-NSS were available for the current analysis. Operated kidney function was assessed by 99mTc-dimercapto-succinic acid (DMSA) renal scintigraphy. Operated kidney volume was assessed by renal ultrasonography.Results
A positive correlation between split renal function and split renal volume was found (P?=?0.001). The subset of patients with ≥ 40% preservation of operated kidney function/volume (OKF/V) had no-time dependent changes during adolescence. The subset of patients with < 40% OKF/V preservation had a catch-up growth that after puberty reached values not much different from those with ≥ 40% OKF/V preservation. At 5?years of follow-up, 3 of 5 patients with baseline dysfunction (eGFR between 40.8 and 89.4?ml/min/1.73?m2) presented with a global renal function within normal range. After puberty, all patients presented with global renal function within normal values (eGFR between 95 and 151?ml/min/1.73 m2).Conclusions
In children with URT who underwent Z-NSS, the pattern of OKF/V recovery suggests that compensatory catch-up growth capacity during childhood minimizes OKF/V decline more than Z-NSS.Level of evidence
Level I prognosis study — prospective cohort study with > 80% follow-up and all patients enrolled at same time point in disease. 相似文献80.
《Brain stimulation》2019,12(6):1526-1536
BackgroundEvidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects.ObjectiveHere, we investigated the longitudinal effects of repeated low-intensity rTMS (LI-rTMS) on healthy rodent resting-state networks (RSNs) using resting-state functional MRI (rs-fMRI) and on sensorimotor cortical neurometabolite levels using proton magnetic resonance spectroscopy (MRS).MethodsSprague-Dawley rats received 10 min LI-rTMS daily for 15 days (10 Hz or 1 Hz stimulation, n = 9 per group). MRI data were acquired at baseline, after seven days and after 14 days of daily stimulation and at two more timepoints up to three weeks post-cessation of daily stimulation.Results10 Hz stimulation increased RSN connectivity and GABA, glutamine, and glutamate levels. 1 Hz stimulation had opposite but subtler effects, resulting in decreased RSN connectivity and glutamine levels. The induced changes decreased to baseline levels within seven days following stimulation cessation in the 10 Hz group but were sustained for at least 14 days in the 1 Hz group.ConclusionOverall, our study provides evidence of long-term frequency-specific effects of LI-rTMS. Additionally, the transient connectivity changes following 10 Hz stimulation suggest that current treatment protocols involving this frequency may require ongoing “top-up” stimulation sessions to maintain therapeutic effects. 相似文献