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51.
52.
Michael Nazarkovsky Albina Mikhraliieva Carlos A. Achete Luiz Anastacio Alves Joyce Araujo Brulio S. Archanjo Jos Júnior Frana de Barros Liana Monteiro da Fonseca Cardoso Jos Nelson S. S. Couceiro Fernanda Davi Marques Bruno S. Oliveira Rafael Nascimento Dias de Souza Ayla Josma Teixeira Thiago L. Vasconcelos Vladimir Zaitsev 《RSC advances》2022,12(23):14342
Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L−1. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™). 相似文献
53.
Prevalence of youth gambling and potential influence of substance use and other risk factors throughout 33 European countries: first results from the 2015 ESPAD study 下载免费PDF全文
Sabrina Molinaro Elisa Benedetti Marco Scalese Luca Bastiani Loredana Fortunato Sonia Cerrai Natale Canale Pavla Chomynova Zsuzsanna Elekes Fernanda Feijão Anastasios Fotiou Anna Kokkevi Ludwig Kraus Liudmila Rupšienė Karin Monshouwer Alojz Nociar Julian Strizek Tanja Urdih Lazar 《Addiction (Abingdon, England)》2018,113(10):1862-1873
54.
Paolo Turchetti Fernanda Pacella Elena Pacella Concetta Mirisola Ilaria Uccella 《European journal of medical research》2012,17(1):3
Unilateral papillitis caused by Treponema pallidum was found in an immunocompetent homosexual patient with severe vision loss who had received previous antibiotics treatment. Syphilis-related ocular manifestation is more common in the early stages of the disease and it can be associated with a central nervous system localization. In this patient, neurosyphilis was diagnosed on the basis of clinical and laboratory findings. Optical examination revealed unilateral papillitis in the left eye and no relative afferent pupillary defects. The patient underwent visual field examinations with conventional perimetry using the 30-2 program of the Humphrey Visual Field Analyzer, which indicated a blind spot enlargement in the left eye. Optical coherence tomography, visual evoked potentials (VEP), and fluorescein angiograms revealed inflammation of the optic nerve head with edematous and blurred margins. A reactive T. pallidum hemagglutination assay with low rapid plasma reagin (RPR) serum titer was performed; an HIV antibody test and MRI of the orbits and head with contrast gave negative results. Resolution of the ocular inflammation after intravenous penicillin treatment was obtained. The reported case illustrates the importance of early recognition of this treatable disease. The rise of syphilis, especially in urban areas, necessitates a high level of suspicion when dealing with patients with intraocular inflammation of unknown origin. Lues serology should be incorporated into routine laboratory diagnostics to aid in the detection of such cases. Considering the re-emergence of syphilis, screening of migrants from countries with high syphilis seroprevalences should be recommended. 相似文献
55.
David E. Barroso Terezinha M.P.P. Casti?eiras Fernanda S. Freitas Jane W. Marsh Mary G. Krauland Mary M. Tulenko érica L. Fonseca Ana C.P. Vicente Maria C. Rebelo Elaine O. Cerqueira Adriano C. Xavier Ana P.C.M. Cardozo Simone E.M. da Silva Lee H. Harrison 《Emerging infectious diseases》2013,19(11):1847-1850
During 2003–2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates. 相似文献
56.
Brandon Eilertson Fernanda Maruri Amondrea Blackman Miguel Herrera David C. Samuels Timothy R. Sterling 《Antimicrobial agents and chemotherapy》2014,58(6):3270-3275
Heteroresistance is the coexistence of populations with differing nucleotides at a drug resistance locus within a sample of organisms. Although Sanger sequencing is the gold standard for sequencing, it may be less sensitive than deep sequencing for detecting fluoroquinolone heteroresistance in Mycobacterium tuberculosis. Twenty-seven fluoroquinolone monoresistant and 11 fluoroquinolone-susceptible M. tuberculosis isolates were analyzed by Sanger and Illumina deep sequencing. Individual sequencing reads were analyzed to detect heteroresistance in the gyrA and gyrB genes. Heteroresistance to fluoroquinolones was identified in 10/26 (38%) phenotypically fluoroquinolone-resistant samples and 0/11 (P = 0.02) fluoroquinolone-susceptible controls. One resistant sample was excluded because of contamination with the laboratory strain M. tuberculosis H37Rv. Sanger sequencing revealed resistance-conferring mutations in 15 isolates, while deep sequencing revealed mutations in 20 isolates. Isolates with fluoroquinolone resistance-conferring mutations by Sanger sequencing all had at least those same mutations identified by deep sequencing. By deep sequencing, 10 isolates had a single fixed (defined as >95% frequency) mutation, while 10 were heteroresistant, 5 of which had a single unfixed (defined as <95% frequency) mutation and 5 had multiple unfixed mutations. Illumina deep sequencing identified a higher proportion of fluoroquinolone-resistant M. tuberculosis isolates with heteroresistance than did Sanger sequencing. The heteroresistant isolates frequently demonstrated multiple mutations, but resistant isolates with fixed mutations each had only a single mutation. 相似文献
57.
Fernanda Neves de Carvalho Carolina Toniolo Zenatti Danila Cassia Reis Santana Juliana Maria da Silva Juliane Cristina Oliveira dos As Katia Kisielow dos Anjos Jessica Sigari Cassia de Lima Santos Marcelle Guerra Olivia Pereira Barros Tomaz Cochemore Roberto Camargo Narciso Mario Lucio Baptista Filho 《The Brazilian journal of infectious diseases》2018
58.
Lívia Alves Amaral Santos Talles Bazeia Lima Laís Augusti Letícia de Campos Franzoni Fabio da Silva Yamashiro Fernanda Bolfi Vânia dos Santos Nunes Mariana de Souza Dorna Cássio Vieira de Oliveira Carlos Antonio Caramori Giovanni Faria Silva Fernando Gomes Romeiro 《Journal of gastroenterology and hepatology》2016,31(1):229-234
59.
Paola Carpinetti Elisa Donnard Fabiana Bettoni Paula Asprino Fernanda Koyama Andrei Rozanski Jorge Sabbaga Angelita Habr-Gama Raphael B. Parmigiani Pedro A.F. Galante Rodrigo O. Perez Anamaria A. Camargo 《Oncotarget》2015,6(35):38360-38371
Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is the mainstay treatment for locally advanced rectal cancer. Variable degrees of tumor regression are observed after nCRT and alternative treatment strategies, including close surveillance without immediate surgery, have been investigated to spare patients with complete tumor regression from potentially adverse outcomes of radical surgery. However, clinical and radiological assessment of response does not allow accurate identification of patients with complete response. In addition, surveillance for recurrence is similarly important for these patients, as early detection of recurrence allows salvage resections and adjuvant interventions. We report the use of liquid biopsies and personalized biomarkers for monitoring treatment response to nCRT and detecting residual disease and recurrence in patients with rectal cancer. We sequenced the whole-genome of four rectal tumors to identify patient-specific chromosomal rearrangements that were used to monitor circulating tumor DNA (ctDNA) in liquid biopsies collected at diagnosis and during nCRT and follow-up. We compared ctDNA levels to clinical, radiological and pathological response to nCRT. Our results indicate that personalized biomarkers and liquid biopsies may not be sensitive for the detection of microscopic residual disease. However, it can be efficiently used to monitor treatment response to nCRT and detect disease recurrence, preceding increases in CEA levels and radiological diagnosis. Similar good results were observed when assessing tumor response to systemic therapy and disease progression. Our study supports the use of personalized biomarkers and liquid biopsies to tailor the management of rectal cancer patients, however, replication in a larger cohort is necessary to introduce this strategy into clinical practice. 相似文献
60.