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73.
Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献
74.
IM Gardiner F Ahmed TJ Steiner A McBain C Kennard J de Belleroche 《Cephalalgia : an international journal of headache》1998,18(4):192-196
The project was an investigation into whether changes in the expression of G-proteins underlie altered cell signaling in migraine and cluster headache. The basis for this assumption is that altered physiological responses are seen in migraineurs and that differences in cell signaling are detected biochemically in various cell types isolated from peripheral blood. Levels of three G-protein mRNAs—Gsα, Giα, and Gqα were quantified in lymphocytes from clinically well-defined migraine and cluster headache patients and correlated with headache type and influence of drug treatment. Giα mRNA was reduced by 50% in all migraine patients compared with control subjects; similarly in patients with or without aura, in patients with a migraine headache at the time of sampling, and patients in a quiescent state. No reduction in the levels of Gsα or Gqα mRNA were seen in migraine patients. A smaller reduction was seen in cluster headache patients, most marked in those without medication. Levels of Gsα. mRNA were significantly reduced in cluster headache patients compared with migraine patients. The marked down-regulation of Giα mRNA in migraine, whether quiescent or acute, indicates either an adaptive response to headache in this group of patients or that low levels of Giα mRNA make individuals more susceptible to migraine. 相似文献
75.
Michael G. Fehlings Branko Kopjar Ahmed Ibrahim Lindsay A. Tetreault Paul M. Arnold Helton Defino Shashank Sharad Kale S. Tim Yoon Giuseppe M. Barbagallo Ronald H.M. Bartels Qiang Zhou Alexander R. Vaccaro Mehmet Zileli Gamaliel Tan Yasutsugu Yukawa Darrel S. Brodke Christopher I. Shaffrey Osmar Santos de Moraes Mark B. Dekutoski 《The spine journal》2018,18(4):593-605
Background Context
Degenerative cervical myelopathy (DCM) is a progressive degenerative spine disease and the most common cause of spinal cord impairment in adults worldwide. Few studies have reported on regional variations in demographics, clinical presentation, disease causation, and surgical effectiveness.Purpose
The objective of this study was to evaluate differences in demographics, causative pathology, management strategies, surgical outcomes, length of hospital stay, and complications across four geographic regions.Study Design/Setting
This is a multicenter international prospective cohort study.Patient Sample
This study includes a total of 757 symptomatic patients with DCM undergoing surgical decompression of the cervical spine.Outcome Measures
The outcome measures are the Neck Disability Index (NDI), the Short Form 36 version 2 (SF-36v2), the modified Japanese Orthopaedic Association (mJOA) scale, and the Nurick grade.Materials and Methods
The baseline characteristics, disease causation, surgical approaches, and outcomes at 12 and 24 months were compared among four regions: Europe, Asia Pacific, Latin America, and North America.Results
Patients from Europe and North America were, on average, older than those from Latin America and Asia Pacific (p=.0055). Patients from Latin America had a significantly longer duration of symptoms than those from the other three regions (p<.0001). The most frequent causes of myelopathy were spondylosis and disc herniation. Ossification of the posterior longitudinal ligament was most prevalent in Asia Pacific (35.33%) and in Europe (31.75%), and hypertrophy of the ligamentum flavum was most prevalent in Latin America (61.25%). Surgical approaches varied by region; the majority of cases in Europe (71.43%), Asia Pacific (60.67%), and North America (59.10%) were managed anteriorly, whereas the posterior approach was more common in Latin America (66.25%). At the 24-month follow-up, patients from North America and Asia Pacific exhibited greater improvements in mJOA and Nurick scores than those from Europe and Latin America. Patients from Asia Pacific and Latin America demonstrated the most improvement on the NDI and SF-36v2 PCS. The longest duration of hospital stay was in Asia Pacific (14.16 days), and the highest rate of complications (34.9%) was reported in Europe.Conclusions
Regional differences in demographics, causation, and surgical approaches are significant for patients with DCM. Despite these variations, surgical decompression for DCM appears effective in all regions. Observed differences in the extent of postoperative improvements among the regions should encourage the standardization of care across centers and the development of international guidelines for the management of DCM. 相似文献76.
BACKGROUND : Red cells (RBCs) stored in hypo-os-molar additive solutions with the same concentrations of adenine, dextrose, mannitol, and sodium chloride and varied amounts of ammonium, phosphate, glycerol, and glutamine were better preserved than RBCs in the standard additive solution (Adsol). Cell swelling occurred in all the experimental additives. This observation prompted the evaluation of glutamine and glycine alone, as well as a combination of glutamine and glycine, all of which have been described as producing swelling of rat liver cells. STUDY DESIGN AND METHODS : Aliquots of RBCs were stored at 4°C in Adsol or experimental additive solutions (EASs) all containing adenine, 2 mM; dextrose, 110 mM; mannitol, 55 mM; and sodium chloride, 50 mM. EAS 42 had, in addition, glutamine, 10 mM; glycine 5 mM; and phosphate, 20 mM. EAS 43 had glutamine, 10 mM; glycine, 10 mM; and phosphate 20 mM. EAS 44 had glutamine, 10 mM; EAS 45 had glutamine, 10 mM, and phosphate, 20 mM; and EAS 46 had only glycine, 10 mM. At intervals, measurements were made of mean corpuscular volume, mean corpuscular hemoglobin concentration, morphology, ATP, hemolysis, supernatant potassium, ammonia, pH, and microvesicles shed. RESULTS : The initial mean corpuscular volumes were larger in all EASs than in Adsol, but the greatest difference was between EASs 44 and 46 (108 fL) and Adsol (86 fL) (p<0.001). The morphology scores were significantly better in all the EASs (p<0.04). The ATPs were significantly greater in all the EASs (p<0.001), and highest in those with phosphate. Potassium leakage and hemolysis were less in the EASs (p<0.001). The ammonia levels were higher in all the EASs than in Adsol, with the exception of EAS 46. During storage, the extracorpuscular and intracorpuscular pH levels were essentially identical. The shedding of microvesicles was greatly reduced in all the EASs. CONCLUSION : Cell swelling induced in RBCs after collection appears to improve preservation. Ammonia and phosphate enhance RBC ATP maintenance. Glycine decreases the formation of ammonia by RBCs stored in a hypotonic medium. 相似文献
77.
Susan M Hinck Patricia Webb Susan Sims-Giddens Caroline Helton Kathryn L Hope Rose Utley Deborah Savinske Elizabeth M Fahey Sue Yarbrough 《Journal of Professional Nursing》2006,22(1):23-29
Concept mapping, a learning strategy used to understand key concepts and relationships between concepts, has been suggested as a method to plan and evaluate nursing care. The purpose of this study was to empirically test the effectiveness of concept mapping for student learning and the students' satisfaction with the strategy. A quasi-experimental pre- and posttest design was used to examine the content of concept maps of care plans constructed by junior-level baccalaureate students (n = 23) at the beginning and end of a community-based mental health course. Additionally, students completed a questionnaire to self-evaluate their learning and report their satisfaction with concept mapping. Findings indicated that concept mapping significantly improved students' abilities to see patterns and relationships to plan and evaluate nursing care, and most students (21/23) expressed satisfaction in using the strategy. This study supported concept mapping as an additional learning strategy and has extended knowledge in community-based nursing education. 相似文献
78.
Green AL Helton WS 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,215(3-4):307-313
High-angle climbing is a physically and cognitively challenging activity. Whilst researchers have examined the physiological demands of climbing, the cognitive demands have been relatively neglected. In this experiment, we examined the performance of climbers when required to perform a dual climbing and word memory task, relative to single-task performance (word memory or climbing alone). Whilst there was no significant decrease in climbing distance during the dual-task condition, climbing efficiency was impaired, as was word recall. Participants' Energetic Arousal, Tense Arousal and Task-unrelated Thoughts (TUTs) all changed dependent on the condition, with arousal increasing after the climbing conditions, and TUTs decreasing after the memory-load conditions. These results could be expanded on in future research to examine the physical and cognitive demands of high-angle climbing in greater detail. 相似文献
79.
Helton WS Russell PN 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,212(3):429-437
In this study, we examined the impact of concurrent verbal and spatial working memory demands on performance on an alpha-numeric
successive target detection task. Seven hundred and forty-five participants performed a target detection task while simultaneously
performing either a spatial or a verbal working memory task or they performed matched no-memory control tasks. The vigilance
decrement, both an increase in target detection response times and a decrease in perceptual sensitivity A′ to target stimuli over time, was exacerbated by concurrent working memory load. The spatial and verbal working memory loads
both impacted vigilance performance suggesting utilization of common executive resources. Overall, these results support the
view that the vigilance decrement results from high cognitive resource demands (e.g., hard work), not from cognitive under-load
(e.g., boredom or mindlessness). 相似文献
80.
Patricia K. Duffner Michele Caggana Joseph J. Orsini David A. Wenger Marc C. Patterson Carl J. Crosley Joanne Kurtzberg Georgianne L. Arnold Maria L. Escolar Darius J. Adams Mary R. Andriola Alan M. Aron Emma Ciafaloni Alexandra Djukic Richard W. Erbe Patricia Galvin-Parton Laura E. Helton Edwin H. Kolodny Barry E. Kosofsky David F. Kronn Melissa P. Wasserstein 《Pediatric neurology》2009,40(4):245-252