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101.
Larson JD Thurman JM Rubtsov AV Claypool D Marrack P van Dyk LF Torres RM Pelanda R 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(18):E1092-E1100
Gammaherpesvirus infections, such as those caused by EBV, have been suggested to promote the development of autoimmunity. To test this idea, we infected healthy WT and lupus-prone B6.Sle123 mice with an EBV-related and rodent-specific gammaherpesvirus, γHV68. Although acute γHV68 infection increased autoantibody levels for 4 to 6 wk, latent infection inhibited these responses for 1 y. The inhibition of autoantibody expression was only observed in B6.Sle123 females and not in males, which already displayed lower autoantibody titers. Contrary to the initial hypothesis, infection of young B6.Sle123 mice, both male and female, resulted in suppression of lymphoid activation and expansion and of glomerular inflammation and sclerosis, preserving kidney function. Moreover, γHV68 infection led to reduced autoantibody titers, lymphoid activation, and glomerular inflammation whether lupus-prone females were infected before or during disease manifestation. Finally, γHV68 infection also inhibited autoantibody production in the genetically distinct MRL/lpr lupus-prone mice. Our findings indicate that γHV68 infection strongly inhibits the development and progression of lupus-like disease in mice that spontaneously develop this condition mediating its beneficial effects at the humoral, cellular, and organ levels. The mechanisms by which the virus exerts this down-modulatory action are not yet clear, but appear to operate via reduced activation of dendritic cells, T cells, and B cells. Gammaherpesviruses coevolved with the vertebrate immune systems, establishing lifelong infections in humans and other mammals. Our findings that γHV68 infection prevents rather than exacerbates autoimmunity in mice suggest that infection with gammaherpesviruses may be protective rather than pathological in most individuals. 相似文献
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103.
Kühn MW Radtke I Bullinger L Goorha S Cheng J Edelmann J Gohlke J Su X Paschka P Pounds S Krauter J Ganser A Quessar A Ribeiro R Gaidzik VI Shurtleff S Krönke J Holzmann K Ma J Schlenk RF Rubnitz JE Döhner K Döhner H Downing JR 《Blood》2012,119(10):e67-e75
To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia. 相似文献
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105.
Baskin JL Reiss U Wilimas JA Metzger ML Ribeiro RC Pui CH Howard SC 《Haematologica》2012,97(5):641-650
Background
Long-term central venous catheters have improved the quality of care for patients with chronic illnesses, but are complicated by obstructions which can result in delay of treatment or catheter removal.Design and Methods
This paper reviews thrombolytic treatment for catheter obstruction. Literature from Medline searches using the terms “central venous catheter”, “central venous access device” OR “central venous line” associated with the terms “obstruction”, “occlusion” OR “thrombolytic” was reviewed. Efficacy of thrombolytic therapy, central venous catheter clearance rates and time to clearance were assessed.Results
Alteplase, one of the current therapies, clears 52% of obstructed catheters within 30 min with 86% overall clearance (after 2 doses, when necessary). However, newer medications may have higher efficacy or shorter time to clearance. Reteplase cleared 67–74% within 30–40 min and 95% of catheters overall. Occlusions were resolved in 70 and 83% of patients with one and 2 doses of tenecteplase, respectively. Recombinant urokinase cleared 60% of catheters at 30 min and 73% overall. Alfimeprase demonstrated rapid catheter clearance with resolution in 40% of subjects within 5 min, 60% within 30 min, and 80% within 2 h. Additionally, urokinase prophylaxis decreased the incidence of catheter occlusions from 16–68% in the control group to 4–23% in the treatment group; in some studies, rates of catheter infections were also decreased in the urokinase group.Conclusions
Thrombolytic agents successfully clear central venous catheter occlusions in most cases. Newer agents may act more rapidly and effectively than currently utilized therapies, but randomized studies with direct comparisons of these agents are needed to determine optimal management for catheter obstruction. 相似文献106.
Raul Gonzalez Igor Grant S. Walden Miller Michael J. Taylor Brian C. Schweinsburg Catherine L. Carey 《The Clinical neuropsychologist》2013,27(3):396-413
Logical grammatical structures comprehension is the ability to understand the relations between objects, actions, and qualities in spoken and written sentences. The Logical Grammatical Structures Test (LGST) was especially devised to assess these abilities in children and adolescents. In the present study the LGST was administered to 405 healthy Dutch children and adolescents. The aims of the present study were (i) to evaluate the psychometric properties of the LGST (using an Item Response Theory framework), and (ii) to establish demographically corrected normative data. The results showed that there was a strong curvilinear relationship between age and LGST performance, i.e., the relative improvement in ability level was much more pronounced for younger children (aged below 14 years) than for older children (aged above 14 years). Level of parental education was positively associated with the LGST performance. Normative data that took the relevant demographic variables into account were established, and it was shown that the LGST had sound psychometric properties. 相似文献
107.
108.
Nazima Sultana Prasanta K. Raul Diganta Goswami Dipankar Das Saidul Islam Varun Tyagi Bodhaditya Das Hemanta K. Gogoi Pronobesh Chattopadhyay Pakalapati S. Raju 《RSC advances》2020,10(16):9356
Background: Vector-borne diseases such as malaria, dengue, yellow fever, encephalitis and filariasis are considered serious human health concerns in the field of medical entomology. Controlling the population of mosquito vectors is one of the best strategies for combating such vector-borne diseases. However, the use of synthetic insecticides for longer periods of time increases mosquito resistance to the insecticides. Recently, the search for new environmentally friendly and efficient insecticides has attracted major attention globally. With the evolution of material sciences, researchers have reported the effective control of such diseases using various sustainable resources. The present investigation demonstrates a potent on-site biolarvicidal agent against different mosquito vectors such as Aedes albopictus, Anopheles stephensi and Culex quinquefasciatus. Methods: Stable and photo-induced colloidal silver nanoparticles were generated via the surface functionalization of the root extract of Cyprus rotundas. Characterizations of the nanoparticles were performed using assorted techniques, such as UV-visible spectroscopy, FTIR spectroscopy, DLS and HRTEM. The bioefficacy of the synthesized nanoparticles was investigated against different species of mosquito larvae through the evaluation of their life history trait studies, fecundity and hatchability rate of the treated larvae. Histopathological and polymerase chain reaction-random amplified polymorphic DNA (RAPD) analyses of the treated larvae were also examined to establish the cellular damage. Results: The synthesized nanoparticles showed remarkable larvicidal activity against mosquito larvae in a very low concentration range (0.001–1.00) mg L−1. The histopathological study confirmed that the present nanoparticles could easily enter the cuticle membrane of mosquito larvae and subsequently obliterate their complete intestinal system. Furthermore, RAPD analysis of the treated larvae could assess the damage of the DNA banding pattern. Conclusion: The present work demonstrates a potent biolarvicidal agent using sustainable bioresources of the aqueous Cyprus rotundas root extract. The results showed that the synthesized nanoparticles were stable under different physiological conditions such as temperature and photo-induced oxidation. The effectiveness of these materials against mosquito larvae was quantified at very low dose concentrations. The present biolarvicidal agent can be considered as an environmentally benign material to control the mosquito vectors with an immense potential for on-site field applications.The present work demonstrates a potent and stable biolarvicidal agent using sustainable bioresources. The synthesized nanomaterials can control the mosquito vectors at a very low concentration range (0.01–1.00 mg L−1) for on-site field applications. 相似文献
109.
The past seventy-five years have witnessed an extraordinary growth of scientific knowledge related to oral health and the development of evidence-based dentistry. The centrality of prevention to the control of oral diseases and the maintenance of good oral health has become increasingly recognized by the scientific community, dental educators, dental practitioners, and the public at large. Yet, despite significant improvements in the overall oral health of Americans, important disparities exist, and large segments of the population are disproportionately burdened by oral diseases. Despite the proven effectiveness of various preventive modalities, such as fluoridation and dental sealants, these have not been universally disseminated and implemented. This review will highlight the challenges remaining in completing the decades-long paradigm shift to prevention and the important role to be played by the dental education community in this process. 相似文献
110.