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排序方式: 共有6425条查询结果,搜索用时 15 毫秒
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Natalia J. Szmacinski Ruth M. DeBar Tina M. Sidener David W. Sidener 《Journal of developmental and physical disabilities》2018,30(5):653-668
The effectiveness of an audio model faded by volume on manding for materials was evaluated within an interrupted behavior chain with two children with autism. Behavior chains were interrupted to contrive an establishing operation (EO) by providing broken items and were interspersed with abolishing operation (AO) trials. An auditory model to teach mands was faded systematically by volume. Using a multiple probe design across three preferred activities, it was found that both participants were manded for some items in the absence of an audio prompt after it was faded systematically. Following the introduction of a prompt delay, participants learned to mand across remaining targets. Across participants, manding generalized to a novel interruption form (i.e., in sight but out of reach materials), to novel materials, and were maintained. Goals, procedures, and outcomes of the intervention were rated socially valid by clinicians. 相似文献
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Natalia A. Pauletti Luiza P. S. Girotto Françoise H. S. Leite Débora N. Mario 《European journal of oral sciences》2017,125(3):223-226
Composite resins are predominantly marketed in developing countries in tube form, and the contents of the tube may be used in numerous procedures for different patients. This represents a problem because of the risk of cross‐contamination. This study aimed to evaluate contamination in vitro of the internal contents of composite resin tubes in the dental clinics of a higher‐education institution, as well as the effect of photoactivation on the level of contamination. Twenty‐five tubes containing composite resin were randomly chosen (by lottery). From each tube, two samples of approximately 2 mm of composite resin were removed, and then one sample, but not the other, was photoactivated. These samples were plated on Brain–Heart Infusion (BHI), Sabouraud and MacConkey agars, and the plates were incubated at 37°C for 24–48 h. Colony counting and Gram staining were performed for subsequent microscopic identification of fungi and bacteria. The non‐photoactivated composite resin group presented significantly higher microbial contamination in relation to the photoactivated composite resin group. The photoactivation of camphorquinone present in composite resin produces reactive oxygen species, which might promote cell death of contaminant microorganisms. Thus, although the same tube of composite resin may be used for a number of different patients in the dental clinics of developing countries, the photoactivation process potentially reduces the risk of cross‐contamination. 相似文献
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Sara F. Ferreiro Natalia Vilariño Cristina Carrera M. Carmen Louzao Germán Santamarina Antonio G. Cantalapiedra Laura P. Rodríguez J. Manuel Cifuentes Andrés C. Vieira K. C. Nicolaou Michael O. Frederick Luis M. Botana 《Archives of toxicology》2014,88(2):425-434
Azaspiracids (AZAs) are marine biotoxins produced by the dinoflagellate Azadinium spinosum that accumulate in several shellfish species. Azaspiracid poisoning episodes have been described in humans due to ingestion of AZA-contaminated seafood. Therefore, the contents of AZA-1, AZA-2 and AZA-3, the best-known analogs of the group, in shellfish destined to human consumption have been regulated by food safety authorities of many countries to protect human health. In vivo and in vitro toxicological studies have described effects of AZAs at different cellular levels and on several organs, however, AZA target remains unknown. Very recently, AZAs have been demonstrated to block the hERG cardiac potassium channel. In this study, we explored the potential cardiotoxicity of AZA-2 in vivo. The effects of AZA-2 on rat electrocardiogram (ECG) and cardiac biomarkers were evaluated for cardiotoxicity signs besides corroborating the hERG-blocking activity of AZA-2. Our results demonstrated that AZA-2 does not induce QT interval prolongation on rat ECGs in vivo, in spite of being an in vitro blocker of the hERG cardiac potassium channel. However, AZA-2 alters the heart electrical activity causing prolongation of PR intervals and the appearance of arrhythmias. More studies will be needed to clarify the mechanism by which AZA-2 causes these ECG alterations; however, the potential cardiotoxicity of AZAs demonstrated in this in vivo study should be taken into consideration when evaluating the possible threat that these toxins pose to human health, mainly for individuals with pre-existing cardiovascular disease when regulated toxin limits are exceeded. 相似文献
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Hancheng Guan Manunya Nuth Natalia Zhukovskaya Yih Ling Saw Edward Bell Stuart N. Isaacs Robert P. Ricciardi 《Antimicrobial agents and chemotherapy》2014,58(12):7383-7389
The dermatological disease molluscum contagiosum (MC) presents as lesions restricted solely to the skin. The poxvirus molluscum contagiosum virus (MCV) is responsible for this skin disease that is easily transmitted through casual contact among all populations, with greater frequency in children and immunosuppressed individuals. In addition, sexual transmission of MCV in adolescents and adults is a health concern. Although the skin lesions ultimately resolve in immunocompetent individuals, they can persist for extended periods, be painful, and result in scarring. Treatment is problematic, and there is no drug that specifically targets MCV. The inability of MCV to propagate in cell culture has impeded drug development. To overcome these barriers, we integrated three new developments. First, we identified a new MCV drug target (mD4) that is essential for processive DNA synthesis in vitro. Second, we discovered a small chemical compound that binds to mD4 and prevents DNA synthesis in vitro. Third, and most significant, we engineered a hybrid vaccinia virus (mD4-VV) in which the natural vaccinia D4 (vD4) gene is replaced by the mD4 target gene. This hybrid virus is dependent on mD4 for viral growth in culture and is inhibited by the small compound. This target system provides, for the first time, a platform and approach for the discovery and evaluation of new therapeutics that can be used to treat MC. 相似文献
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