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The aim of this study was to investigate the in vitro immunomodulatory effects of zoledronic acid (Zol) on peripheral blood Vgamma9/Vdelta2 (gammadelta) T cells of normal donors and multiple myeloma (MM) patients. gammadelta T cells were stimulated with Zol and low doses of interleukin-2 (IL-2), and then analyzed for proliferation, cytokine production, and generation of effector activity against myeloma cell lines and primary myeloma cells. Proliferation of gammadelta T cells was observed in 100% of normal donors and 50% of MM patients. gammadelta T cells produced IFN-gamma, surface mobilized the CD107a and CD107b antigens, and exerted direct cell-to-cell antimyeloma activity irrespective of the ability to proliferate to Zol and IL-2. The memory phenotype was predominant in the MM gammadelta T cells that proliferated in response to Zol (responders), whereas effector cells were predominant in those that did not (nonresponders). Zol induced antimyeloma activity through the monocyte-dependent activation of gammadelta T cells and by enhancing the immunosensitivity of myeloma cells to gammadelta T cells. Mevastatin, a specific inhibitor of hydroxy-methylglutaryl-CoA reductase, completely abrogated this antimyeloma activity.  相似文献   
104.
B Bruno  L Giaccone  M Rotta  K Anderson  M Boccadoro 《Leukemia》2005,19(10):1729-1738
Multiple myeloma remains an incurable plasma cell neoplasm. New insights into its pathogenesis have identified signaling pathways that have become potential therapeutic targets. It has clearly been established that intracellular regulatory proteins and interactions between malignant plasma cells and the bone marrow microenvironment play an important role in their survival and drug resistance. Several new agents associated with molecular targets are currently being investigated to design new treatment strategies aimed at prolonging survival and improving quality of life. This review illustrates their mechanisms of action and the possible future clinical applications.  相似文献   
105.
Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63‐year‐old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap.  相似文献   
106.
Bites of brown spiders (Loxosceles spp.) are responsible for dermonecrotic lesions and potentially systemic envenoming that can lead to death. The only effective therapy is the use of the antivenom, usually produced in horses. However, little is known about the consequences of the systematic use of the Loxosceles venom and adjuvants and of the bleedings on antivenom-producing horses. Thus, the aim of this study was to evaluate the clinical changes in horses in their first immunization protocol for Loxosceles antivenom production. Eleven healthy horses, never immunized, were evaluated in three different periods: T0 (before immunization); T1 (after their first venom immunization); and T2 (after their first bleeding). Horses were clinically evaluated, sampled for blood, and underwent electrocardiographic (ECG) recordings. Several suppurated subcutaneous abscesses occurred due to the use of Freund’s adjuvants and thrombophlebitis due to systematic venipunctures for the bleeding procedures. ECG showed arrhythmias in few horses in T2, such as an increase in T and R waves. In summary, the immunization protocol impacted on horses’ health, especially after bleeding for antivenom procurement.  相似文献   
107.
Brazil is blessed with a great biodiversity, which constitutes one of the most important sources of biologically active compounds, even if it has been largely underexplored. As is the case of the Amazon and Atlantic rainforests, the Brazilian marine fauna remains practically unexplored in the search for new biologically active natural products. Considering that marine organisms have been shown to be one of the most promising sources of new bioactive compounds for the treatment of different human diseases, the 8000 km of the Brazilian coastline represents a great potential for finding new pharmacologically active secondary metabolites. This review presents the status of marine natural products chemistry in Brazil, including results reported by different research groups with emphasis on the isolation, structure elucidation, and evaluation of biological activities of natural products isolated from sponges, ascidians, octocorals, and Opistobranch mollusks. A brief overview of the first Brazilian program on the isolation of marine bacteria and fungi, directed toward the production of biologically active compounds, is also discussed. The current multidisciplinary collaborative program under development at the Universidade de S?o Paulo proposes to establish a new paradigm toward the management of the Brazilian marine biodiversity, integrating research on the species diversity, ecology, taxonomy, and biogeography of marine invertebrates and microorganisms. This program also includes a broad screening program of Brazilian marine bioresources, to search for active compounds that may be of interest for the development of new drug leads.  相似文献   
108.
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events.  相似文献   
109.
Background:Previous research has identified that people with type 2 diabetes (T2D) within the Hispanic community would benefit from an online peer support community (OPSC) and continuous glucose monitoring (CGM) data to facilitate diabetes self-management.Methods:A mixed-methods feasibility study enrolled Hispanic, Spanish-speaking adults with T2D, not on insulin. Participants were provided with CGM and access to an OPSC for 12 weeks. Feasibility was assessed by number of eligible participants who enrolled, attrition, quantity of CGM data, validated clinical measures of self-efficacy, quality of life and adverse events. Engagement in the OPSC was measured using objective metrics on the online platform. Qualitative interviews were conducted upon conclusion of the intervention to assess feasibility, acceptability, participant satisfaction, and key recommendations for improvement.Results:Of 46 participants screened, 39 were eligible and 26 completed the study. Participants significantly improved self-efficacy scores. Posts in the OPSC related to goal setting had the highest engagement followed by mid-week and end of week check-in posts respectively. Participant interviews described challenges accessing the OPSC platform as a barrier to engagement. Despite this, all participants were satisfied with the intervention. Key recommendations for improvement included providing greater variety of and individualized education and the use of a peer support platform that is easily accessible.Conclusions:The CGM + OPSC intervention tailored to the Hispanic community with T2D was feasible, acceptable and satisfactory and improved participant self-efficacy for diabetes management which may lead to improved clinical outcomes.  相似文献   
110.
COVID-19 mitigation efforts had the potential to exacerbate loneliness among older adults, particularly for the unpartnered or childless, yet specific studies on loneliness among these groups during the COVID-19 pandemic are lacking. Using data from the Survey of Health, Ageing and Retirement in Europe (SHARE) collected before (October 2019–March 2020) and during the pandemic (June–August 2020), we examine two loneliness outcomes: (1) “have you felt lonely recently?” (both datasets) and (2) “have you felt lonelier than before the pandemic?” (2020), and examine differences by partnership and parenthood status. Before COVID-19, those who lacked one tie but had the other (unpartnered parents or partnered childless) were at highest loneliness risk. During COVID-19, unpartnered and childless—especially unpartnered—remain at higher risk for loneliness, entering loneliness, and not “exiting” loneliness. We discuss these findings in light of family norms and needs in pandemic and non-pandemic times and provide recommendations for future research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00718-x.  相似文献   
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