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991.
Vega B Muñoz LM Holgado BL Lucas P Rodríguez-Frade JM Calle A Rodríguez-Fernández JL Lechuga LM Rodríguez JF Gutiérrez-Gallego R Mellado M 《Journal of leukocyte biology》2011,90(2):399-408
Use of SPR-based biosensors is an established method for measuring molecular interactions. Their application to the study of GPCRs is nonetheless limited to detergent-solubilized receptors that can then be reconstituted into a lipid environment. Using the chemokine receptor CXCR4 and its specific ligand CXCL12, we outline here a highly reproducible biosensor method based on receptor presentation on the surface of lentiviral particles; the approach is simple and does not require the use of antibodies to achieve correct receptor orientation on the sensorchip surface. We measured the kinetic parameters of CXCR4/CXCL12 binding in a single step and in real time and evaluated the effect of GAG presentation of chemokines on this interaction. The data indicate that at low concentrations, soluble heparin modulates CXCR4/CXCL12 interaction and at high concentrations, abrogates binding. These observations suggest that in addition to their known role in modulating local chemokine availability, GAG affect the receptor/ligand interaction, although their influence on affinity parameters is very limited. The method will also be useful for quantifying these biomarkers in biological fluids and for the development of high-throughput screening for their antagonists. 相似文献
992.
993.
Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia are periodontal pathogens associated with the etiology of adult periodontitis as polymicrobial infections. Recent studies demonstrated that oral infection with P. gingivalis induces both periodontal disease and atherosclerosis in hyperlipidemic and proatherogenic ApoE(-/-) mice. In this study, we explored the expression of microRNAs (miRNAs) in maxillas (periodontium) and spleens isolated from ApoE(-/-) mice infected with P. gingivalis, T. denticola, and T. forsythia as a polymicrobial infection. miRNA expression levels, including miRNA miR-146a, and associated mRNA expression levels of the inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) were measured in the maxillas and spleens from mice infected with periodontal pathogens and compared to those in the maxillas and spleens from sham-infected controls. Furthermore, in response to these periodontal pathogens (as mono- and polymicrobial heat-killed and live bacteria), human THP-1 monocytes demonstrated similar miRNA expression patterns, including that of miR-146a, in vitro. Strikingly, miR-146a had a negative correlation with TNF-α secretion in vitro, reducing levels of the adaptor kinases IL-1 receptor-associated kinase 1 (IRAK-1) and TNF receptor-associated factor 6 (TRAF6). Thus, our studies revealed a persistent association of miR-146a expression with these periodontal pathogens, suggesting that miR-146a may directly or indirectly modulate or alter the chronic periodontal pathology induced by these microorganisms. 相似文献
994.
Kelly PJ Lucas H Yowell C Beati L Dame J Urdaz-Rodriguez J Mahan S 《Journal of medical entomology》2011,48(2):485-488
The highly sensitive nested pCS20 polymerase chain reaction assay for Ehrlichia ruminantium was negative on 506 Amblyomma variegatum from Caribbean islands where clinical heartwater has not been reported, mainly the United States Virgin Islands (18), Dominica (170), Montserrat (5), Nevis (34), St. Kitts (262), and St. Lucia (17). Positive results were obtained with positive controls (Crystal Springs strain) and A. variegatum from countries in Africa where infections are endemic, mainly Tanzania (1/37) and Burkino Faso (2/29). Positive major antigenic protein-1 enzyme-linked immunosorbent assays for E. ruminantium were obtained on convenience samples of sera from apparently healthy cattle, sheep, and goats on Dominica (0/95, 0%; 3/135, 2%; 2/57, 4%), Grenada (0/4, 0%; 1/98, 1%; 1/86, 1%), Montserrat (0/12, 0%; 0/28, 2%; 5/139, 4%), Nevis (0/45, 0%; 0/157, 0%; 0/90, 0%), Puerto Rico (0/422, 0%; 0, 0%), St. Kitts (3/86, 4%; 1/25, 0%; 0/26, 0%), and St. Lucia (0/184, 0%; 0/15, 0%; 0, 0%), respectively. The pCS20 polymerase chain reaction results indicate E. ruminantium is not present on islands where clinical heartwater does not occur. The occasional positive major antigenic protein-1B enzyme-linked immunosorbent assay results appear, then, to be false-positive reactions, and serology appears to be of limited use in testing for E. ruminantium in the Caribbean, as is the case in Africa. 相似文献
995.
996.
997.
D. H. Heo Y. J. Cho S. H. Sheen S. U. Kuh S. M. Cho S. M. Oh 《Osteoporosis international》2009,20(12):2063-2070
Summary
This study was undertaken to investigate the radiologic and clinical outcomes of vertebroplasty with calcium phosphate (CaP) cement in patients with osteoporotic vertebral compression fractures. The morphological changes of injected CaP cement in osteoporotic compressed vertebral bodies were variable and unpredictable. We suggest that the practice of vertebroplasty using CaP should be reconsidered. 相似文献998.
999.
Confusion between radicular and nerve trunk syndrome is not rare. With sciatic pain, any nerve trunk pain or an atypical nerve course should suggest nerve trunk pain of the sciatic nerve in the buttocks. The usual reflex with sciatic pain is vertebral-radicular conflict. The absence of spinal symptoms and the beginning of pain in the buttocks and not in the lumbar region should reorient the etiologic search.Once a tumor of the nerve trunk has been ruled out (rarely responsible for pain other than that caused by tumor pressure), a myofascial syndrome should be explored searching for clinical, electrophysiological, and radiological evidence of compression of the sciatic trunk by the piriform muscle but also the obturator internus muscle.Hamstring syndrome may be confused with this syndrome.Treatment is first and foremost physical therapy. Failures can be treated with classical CT-guided infiltrations with botulinum toxin.Surgery should only be entertained when all these solutions have failed. 相似文献
1000.
Oh Young Bang Bruce Ovbiagele David S. Liebeskind Lucas Restrepo Sa Rah Yoon Jeffrey L. Saver 《Journal of neurology》2009,256(4):591-599
Abstract
Background
Although stroke from large vessel atherothromboembolism has a common pathogenesis, its topographic presentation is variable.
Given the impact of cerebral infarct size and location on incident stroke magnitude and subsequent prognosis, we evaluated
the determinants of cerebral infarct topography among patients with atherosclerotic stroke.
Methods
We analyzed data on 148 consecutive patients admitted over a 4-year period to a university medical center with acute ischemic
stroke within the MCA distribution on DWI, presumed due to atherosclerosis. Based on the DWI data, we divided the patients
into three stroke phenotypes: large cortical, small (< 1 cm in diameter) cortical, and deep pattern. Independent factors for
each stroke phenotype were evaluated using logistic regression.
Results
After adjusting for covariates, premorbid statin use (OR, 3.05; 95 % CI, 1.40–6.65) and older age (OR, 1.05 per 1 year increase;
95 % CI, 1.02–1.08) were independently associated with the small cortical phenotypic pattern. In contrast, younger age (OR,
0.95 per 1 year increase; 95 % CI, 0.92–0.98), premorbid statin non-use (OR, 0.40; 95 % CI, 0.17–0.99), and higher levels
of fasting s-glucose (OR, 1.01 per 1 mg/dl increase; 95 % CI, 1.00–1.02) and admission peripheral WBC counts (OR, 1.13 per
1 × 109 cells/L; 95 % CI, 1.00–1.27) were independently associated with the large cortical pattern. There was no relation between
DWI patterns and LDL-cholesterol levels.
Conclusions
Age, premorbid statin use, s-glucose and WBC count predict atherosclerotic stroke phenotype. Further studies should examine
whether modifying some of these factors may result in more favorable phenotypic patterns.
Electronic Supplementary Material The online version of this article (DOI) contains supplementary material, which is available to authorized users. 相似文献