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51.
Carlos Franciney Moreira Vasconcelos Nívea Maria da Cunha Ferreira Nayanne Hardy Lima Pontes Thomas Dominik de Sousa dos Reis Ricardo Basto Souza Francisco Eduardo Arago Catunda Junior Lissiana Magna Vasconcelos Aguiar Rodrigo Maranguape Silva da Cunha 《Basic & clinical pharmacology & toxicology》2020,127(4):287-302
Parkinson's disease is a neurodegenerative disorder that affects the central nervous system and is mainly characterized by the loss of dopaminergic neurons and pro‐oxidant mechanisms. Eugenol has been widely studied due to its anti‐inflammatory and antioxidant activities, making it a promising neuroprotective agent. This study aimed to investigate the effects of eugenol and its combined action with levodopa in the 6‐hydroxydopamine‐induced Parkinson's disease model. Wistar rats were subjected to intrastriatal injection of 6‐hydroxydopamine (21 μg) and then treated with eugenol (0.1, 1, or 10 mg/kg), levodopa (25 mg/kg) or their combination (eugenol 10 mg/kg + levodopa 12.5 mg/kg) orally for 14 days. On the 14th day, the animals were subjected to behavioural tests, and after euthanization and dissection of the brain areas, neurochemical analyses were performed. The results showed that eugenol reduced the oxidative stress and behavioural disturbances induced by 6‐hydroxydopamine. The eugenol and levodopa combination was more effective in some behavioural parameters and body‐weight gain in addition to promoting an increase in reduced glutathione levels compared to levodopa alone. Thus, the neuroprotective activity of eugenol was observed against motor and neurochemical disorders. Additionally, the eugenol and levodopa combination was promising when compared to conventional treatment. 相似文献
52.
Chiang Jannifer O. Azevedo Rafael S. Justino Maria C. A. Matos Haroldo J. Cabeça Hideraldo L. S. Silva Sandro P. Henriques Daniele F. Silva Eliana V. P. Andrade Gabriela S. S. Vasconcelos Pedro FC. Martins Lívia C. Azevedo Raimunda S. S. 《Journal of neurovirology》2021,27(4):626-630
Journal of NeuroVirology - We describe two neurological cases of Oropouche virus infection in northern Brazil, where the virus is endemic but neglected as a pathogen. This study reiterates the... 相似文献
53.
G.S.B. Viana E.M. do Vale A.R.A. de Araujo N.C. Coelho S.M. Andrade R.O. da Costa P.E.A. de Aquino C.N.S. de Sousa I.S. de Medeiros S.M.M. de Vasconcelos K.R.T. Neves 《Brazilian journal of medical and biological research》2021,54(2)
Ketamine (KET) is an N-methyl-D-aspartate (NMDA) antagonist with rapid and long-lasting antidepressant effects, but how the drug shows its sustained effects is still a matter of controversy. The objectives were to evaluate the mechanisms for KET rapid (30 min) and long-lasting (15 and 30 days after) antidepressant effects in mice. A single dose of KET (2, 5, or 10 mg/kg, po) was administered to male Swiss mice and the forced swim test (FST) was performed 30 min, 15, or 30 days later. Imipramine (IMI, 30 mg/kg, ip), a tricyclic antidepressant drug, was used as reference. The mice were euthanized, separated into two time-point groups (D1, first day after KET injection; D30, 30 days later), and brain sections were processed for glycogen synthase kinase-3 (GSK-3), histone deacetylase (HDAC), brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP) immunohistochemical assays. KET (5 and 10 mg/kg) presented rapid and long-lasting antidepressant-like effects. As expected, the immunoreactivities for brain GSK-3 and HDAC decreased compared to control groups in all areas (striatum, DG, CA1, CA3, and mainly pre-frontal cortex, PFC) after KET injection. Increases in BDNF immunostaining were demonstrated in the PFC, DG, CA1, and CA3 areas at D1 and D30 time-points. GFAP immunoreactivity was also increased in the PFC and striatum at both time-points. In conclusion, KET changed brain BDNF and GFAP expressions 30 days after a single administration. Although neuroplasticity could be involved in the observed effects of KET, more studies are needed to explain the mechanisms for the drug’s sustained antidepressant-like effects. 相似文献
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55.
Eduarda Helena Leandro Nascimento Rocharles Cavalcante Fontenele Priscila de Azeredo Lopes Gustavo Machado Santaella Karla Faria Vasconcelos Deborah Queiroz de Freitas Anne Caroline Oenning Francisco Carlos Groppo 《Dento maxillo facial radiology》2021,50(3)
Objectives:To present the ballistic gelatin as a new material capable of simulating the soft tissues in cone-beam CT (CBCT) images.Methods:CBCT images of three piglet heads were acquired with their soft tissues intact (standard group). Subsequently, the piglet heads were fixed in a container using metallic pins and moulded with acrylic resin; the soft tissues were then removed and replaced by ballistic gelatin, with the same thickness of the original soft tissues. The images were evaluated by two oral radiologists, to check the adaptation on bone surfaces, thickness and density, penetration into large bone cavities and cancellous bone, and the presence of air bubbles using a 5-score scale. Additionally, an objective analysis was carried out by one oral radiologist. For each CBCT scan, three axial reconstructions were selected to represent the mandibular, occlusal, and maxillary levels. The mean and standard deviation (SD) of the grey values were calculated in four regions of interest determined on soft tissue areas and compared by two-way ANOVA.Results:The ballistic gelatin showed subjective scores ranging from good to excellent for all parameters evaluated. There was no significant difference in the mean and SD values of the grey values between ballistic gelatin and the gold standard groups for all levels (p > 0.05). Higher SD values were observed in the occlusal level for both groups (p < 0.05).Conclusions:Ballistic gelatin has visual and objective similarity with the gold standard. Thus, the ballistic gelatin is a promising material capable of simulating soft tissues in CBCT images. 相似文献
56.
The environmental health-related relevance of cyanobacteria is primarily related to their ability to produce a wide range of toxins, which are known to be hazardous to many organisms, including human beings. The occurrence of cyanobacterial blooms has been related to eutrophic surface water. In the bloom-forming process the levels of phosphorus and nitrogen have been well documented but information regarding concentrations of other chemicals (inorganic, organo-metallic, and organic) is still incipient. Several contaminants, like trace metals, elicit a variety of acute and chronic toxicity effects, but cyanobacteria also have the capability to accumulate, detoxify, or metabolize such substances, to some extent. The role of cyanobacterial exudates has been proved a means of both nutrient acquisition and detoxification. In addition, cyanobacteria are effective biological metal sorbents, representing an important sink for metals in aquatic environment. Understanding the fundamental physicochemical mechanisms of trace metal bio-uptake by cyanobacteria in natural systems is a step towards identifying under what conditions cyanobacterial growth is favored and to ascertain the mechanisms by which blooms (and toxin production) are triggered. In this review the cyanobacterial interactions with metals will be discussed, focusing on freshwater systems. 相似文献
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58.
Vasconcelos Camila Vilela Costa Alan Carlos Müller Caroline Castoldi Gustavo Costa Andréia Mendes de Paula Barbosa Kássia Rodrigues Arthur Almeida da Silva Adinan Alves 《Ecotoxicology (London, England)》2020,29(2):203-216
Ecotoxicology - Common bean (Phaseolus vulgaris) cultivation occurs mainly in regions with acidic soils, where high aluminum (Al) concentration is a major constraint to crop production. In this... 相似文献
59.
Fernando Tadeu Vasconcelos Amaral Paulo Henrique Manso André Schmidt Ricardo Nilson Sgarbieri Walter Villela de Andrade Vicente Clovis Carbone Junior Jane Somerville 《Brazilian Journal Of Cardiovascular Surgery》2015,30(3):373-379
During the last decades, advances in diagnosis and treatment of congenital heart
disease have allowed many individuals to reach adulthood. Due mainly to the great
diagnostic diversity and to the co-morbidities usually present in this age group,
these patients demand assistance in a multidisciplinary facility if an adequate
attention is aimed. In this paper we reviewed, based in the international literature
and also on the authors’ experience, the structural conditions that should be
available for these patients. We highlighted aspects like the facility
characteristics, the criteria usually adopted for patient transfer from the
paediatric setting, the composition of the medical and para- medical staff taking
into account the specific problems, and also the model of outpatient and in-hospital
assistance. We also emphasized the importance of patient data storage, the
fundamental necessity of institutional support and also the compromise to offer
professional training. The crucial relevance of clinical research is also approached,
particularly the development of multicenter studies as an appropriate methodology for
this heterogeneous patient population. 相似文献
60.