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71.
Novák J Benísek M Pacherník J Janosek J Sídlová T Kiviranta H Verta M Giesy JP Bláha L Hilscherová K 《Environmental toxicology and chemistry / SETAC》2007,26(8):1591-1599
Retinoids are known to regulate important processes such as differentiation, development, and embryogenesis. Some effects, such as malformations in frogs or changes in metabolism of birds, could be related to disruption of the retinoid signaling pathway by exposure to organic contaminants. A new reporter gene assay has been established for evaluation of the modulation of retinoid signaling by individual chemicals or environmental samples. The bioassay is based on the pluripotent embryonic carcinoma cell line P19 stably transfected with the firefly luciferase gene under the control of a retinoic acid-responsive element (clone P19/ A15). The cell line was used to characterize the effects of individual chemicals and sediments extracts on retinoid signaling pathways. The extracts of sediments from the River Kymi, Finland, which contained polychlorinated dioxins and furans and polycyclic aromatic hydrocarbons (PAHs), significantly increased the potency of all-trans retinoic acid (ATRA), while no effect was observed with the extract of the sediment from reference locality. Considerable part of the effect was caused by the labile fraction of the sediment extracts. Also, several individual PAHs potentiated the effect of ATRA; on the other hand, 2,3,7,8-tetrachlorodibenzo-p-dioxin and several phthalates showed slightly inhibiting effect. These results suggest that PAHs could be able to modulate the retinoid signaling pathway and that they could be responsible for a part of the proretinoid activity observed in the sediment extracts. However, the effects of PAHs on the retinoic acid signaling pathways do not seem to be mediated directly by crosstalk with aryl hydrocarbon receptor. 相似文献
72.
Origins of the Xylella fastidiosa Prophage-Like Regions and Their Impact in Genome Differentiation
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Alessandro de Mello Varani Rangel Celso Souza Helder I. Nakaya Wanessa Cristina de Lima Luiz Gonzaga Paula de Almeida Elliot Watanabe Kitajima Jianchi Chen Edwin Civerolo Ana Tereza Ribeiro Vasconcelos Marie-Anne Van Sluys 《PLoS Clinical Trials》2008,3(12)
Xylella fastidiosa is a Gram negative plant pathogen causing many economically important diseases, and analyses of completely sequenced X. fastidiosa genome strains allowed the identification of many prophage-like elements and possibly phage remnants, accounting for up to 15% of the genome composition. To better evaluate the recent evolution of the X. fastidiosa chromosome backbone among distinct pathovars, the number and location of prophage-like regions on two finished genomes (9a5c and Temecula1), and in two candidate molecules (Ann1 and Dixon) were assessed. Based on comparative best bidirectional hit analyses, the majority (51%) of the predicted genes in the X. fastidiosa prophage-like regions are related to structural phage genes belonging to the Siphoviridae family. Electron micrograph reveals the existence of putative viral particles with similar morphology to lambda phages in the bacterial cell in planta. Moreover, analysis of microarray data indicates that 9a5c strain cultivated under stress conditions presents enhanced expression of phage anti-repressor genes, suggesting switches from lysogenic to lytic cycle of phages under stress-induced situations. Furthermore, virulence-associated proteins and toxins are found within these prophage-like elements, thus suggesting an important role in host adaptation. Finally, clustering analyses of phage integrase genes based on multiple alignment patterns reveal they group in five lineages, all possessing a tyrosine recombinase catalytic domain, and phylogenetically close to other integrases found in phages that are genetic mosaics and able to perform generalized and specialized transduction. Integration sites and tRNA association is also evidenced. In summary, we present comparative and experimental evidence supporting the association and contribution of phage activity on the differentiation of Xylella genomes. 相似文献
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Borilova Linhartova Petra Deissova Tereza Musilova Kristina Zackova Lenka Kukletova Martina Kukla Lubomir Izakovicova Holla Lydie 《Clinical oral investigations》2018,22(4):1873-1877
Clinical Oral Investigations - The enamelin gene (ENAM) polymorphism (rs12640848) was recently associated with dental caries in primary teeth in Polish children. The aims of the present study were... 相似文献
77.
AJ Barrêto LD Sá Jde A Nogueira PF Palha PG Pinheiro NM Farias DC Rodrigues TC Villa 《Ciência & saúde coletiva》2012,17(7):1875-1884
The scope of this study was to analyze the discourse of managers regarding the relationship between the organization of the health services and tuberculosis care management in a city in the metropolitan region of Jo?o Pessoa, State of Pernambuco. Using qualitative research in the analytical field of the French line of Discourse Analysis, 16 health workers who worked as members of the management teams took part in the study. The transcribed testimonials were organized using Atlas.ti version 6.0 software. After detailed reading of the empirical material, an attempt was made to identify the paraphrasic, polyssemic and metaphoric processes in the discourses, which enabled identification of the following discourse formation: Organization of the health services and the relation with TB care management: theory and practice. In the discourse of the managers the fragmentation of the actions of control of tuberculosis, the lack of articulation between the services and sectors, the compliance of the specific activities for TB, as well as the lack of strategic planning for management of care of the disease are clearly revealed. In this respect, for the organization of the health services to be effective, it is necessary that tuberculosis be considered a priority and acknowledged as a social problem in the management agenda. 相似文献
78.
Cordeiro Rde A e Silva KR Brilhante RS Moura FB Duarte NF Marques FJ Cordeiro Rde A Filho RE de Araújo RW Bandeira Tde J Rocha MF Sidrim JJ 《Emerging infectious diseases》2012,18(4):668-670
To analyze the eco-epidemiologic aspects of Histoplasma capsulatum in Brazil, we tested 83 bats for this fungus. Although H. capsulatum was not isolated, Coccidioides posadasii was recovered from Carollia perspicillata bat lungs. Immunologic studies detected coccidioidal antibodies and antigens in Glossophaga soricina and Desmodus rotundus bats. 相似文献
79.
Matos LN Guimarães TC Brandão MA Santoro DC 《Revista latino-americana de enfermagem》2012,20(2):307-315
The purposes of the study were to identify the prevalence of defining characteristics (DC) of decreased cardiac output (DCO) in patients with cardiac insufficiency under evaluation for heart transplantation, and to ascertain the likelihood of defining characteristics being predictive factors for the existence of reduction in cardiac output. Data was obtained by retrospective documental analysis of the clinical records of right-sided heart catheterizations in 38 patients between 2004 and 2009. The results showed that 71.1% of the patients had decreased cardiac output (measured by cardiac index). The majority of the NANDA-International defining characteristics for DCO were more frequent in individuals with reduced cardiac index levels. The study emphasizes the odds ratio (OR) for increased Systemic Vascular Resistance of OR=4.533, of the third heart sound with OR=3.429 and the reduced ejection fraction with OR=2.850. By obtaining the predictive values for the defining characteristics the study identifies them as diagnostic indicators of decreased cardiac output. 相似文献
80.
Provaznikova D Kumstyrova T Kotlin R Salaj P Matoska V Hrachovinova I Rittich S 《Platelets》2008,19(6):471-475
May-Hegglin anomaly (MHA), Sebastian (SBS), Fechtner (FTNS) and Epstein (EPS) syndromes are rare autosomal dominant disorders with giant platelets and thrombocytopenia. Other manifestations of these disorders are combinations of the presence of granulocyte inclusions and deafness, cataracts and renal failure. Currently, MHA, SBS, FTNS and EPS are considered to be distinct clinical manifestation of a single illness caused by mutations of the MYH9 gene encoding the heavy chain of non-muscle myosin IIA (NMMHC-IIA). As the MYH9 gene has a high number of exons, it takes much time and material to use this method for the detection of MYH9 mutations. Recently, a new method has been introduced for scanning DNA mutations without the need for direct sequencing: high-resolution melting analysis (HRMA). Mutation detection with HRMA relies on the intercalation of the specific dye (LC Green plus) in double-strand DNA and fluorescence monitoring of PCR product melting profiles. In our study, we optimized the conditions and used HRMA for rapid screening of mutations in all MYH9 exons in seven affected individuals from four unrelated families with suspected MYH9 disorders. Samples identified by HRMA as positive for the mutation were analysed by direct sequencing. HRMA saved us over 85% of redundant sequencing. 相似文献