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71.
Prevalence of anti BK virus antibody in Portugal and Norway 总被引:3,自引:0,他引:3
T Flaegstad K R?nne A R Filipe T Traavik 《Scandinavian journal of infectious diseases》1989,21(2):145-147
Specific IgG antibodies against BK virus measured by ELISA were used as a marker of previous infection. Results with sera from healthy people of different counties in Portugal were compared with previous findings in Norwegian sera. No significant difference between the prevalence and level of BKV IgG could be found between Portugal and Norway, and when comparing the different counties of Portugal. Thus, the way of transmission seemed to follow the same routes both in rural and urban counties in Portugal, and in Norway. 相似文献
72.
Dhori and Thogoto viruses are till now the only recognized tick-borne orthomyxoviruses. Like Thogoto virus, also Dhori is highly hepatotropic for laboratory mice; the lesions in several organs resemble those described for influenza virus. 相似文献
73.
c-erbB-2 proto-oncogene expression and its relationship to survival in gastric carcinoma: an immunohistochemical study on archival material. 总被引:4,自引:0,他引:4
S Jain M I Filipe W J Gullick J Linehan R W Morris 《International journal of cancer. Journal international du cancer》1991,48(5):668-671
The c-erbB-2 proto-oncogene encodes a growth factor receptor which is over-expressed in a variety of human adenocarcinomas. Recent reports suggest that it may be of value in arriving at prognosis in breast and ovarian cancer. In this study, c-erbB-2 expression was investigated in 93 routinely processed cases of gastric carcinoma, using an immunohistochemical technique. c-erbB-2 membrane immunoreactivity was observed in 11% (10/93) of tumours, all of which were of the well differentiated intestinal type (p less than 0.01). Overall, patients with tumours expressing this proto-oncogene had a significantly improved prognosis (p less than 0.05). Within the group of intestinal-type tumours, those that were c-erbB-2-positive formed a distinct sub-population which had a better prognosis (p less than 0.02), suggesting possible differences in aetiology. 相似文献
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76.
Sara Rapic Christel Vangestel Filipe Elvas Jeroen Verhaeghe Tim Van den Wyngaert Leonie wyffels Patrick Pauwels Steven Staelens Sigrid Stroobants 《Molecular imaging and biology》2017,19(4):560-569
Purpose
The substrate-based positron emission tomography (PET) tracer [18F]CP18 is capable of detecting the activity of caspase-3/7, two key executioner proteases in the apoptosis pathway, through selective cleavage of the ligand by the activated proteases and subsequent accumulation in apoptotic cells. Using an in vitro and in vivo model of colorectal cancer (CRC), we investigated whether [18F]CP18 tracer accumulation provides a measure for apoptosis and reliably reflects early treatment response to chemotherapeutics.Procedures
[18F]CP18 cell uptake was assessed in treated Colo205 cells (saline, 5-fluorouracil (5-FU), irinotecan or their combination) and correlated with caspase-3/7 activity. [18F]CP18 imaging was performed in Colo205 xenografts, starting with a baseline μPET/micro X-ray computed tomography (?μCT) scan, followed by a 3-day treatment with saline (n = 5), 5-FU (low sensitivity, n = 4), irinotecan (high sensitivity, n = 5), or a combination of both (n = 7). The study was concluded with a second [18F]CP18 scan, 24 h after final treatment administration, followed by tumor removal for gamma counting (%ID/g) and for cleaved caspase-3 immunohistochemistry (apoptotic index/necrosis). Tumors were delineated on μCT images and, using the obtained volumes of interest, average percentage injected dose per cubic centimeter (%ID/cm3) was calculated from every μPET image.Results
In vitro, [18F]CP18 cell uptake was positively correlated with caspase-3/7 activity (r = 0.59, p = 0.003). A drug-dependent increase in [18F]CP18 tumor uptake compared to baseline was observed in animals treated with 5-FU (+14 ± 25 %), irinotecan (+56 ± 54 %), and their combination (+158 ± 69 %, p = 0.002). %ID/cm3 showed a positive relationship with both %ID/g (r = 0.83, p < 0.0001) and the apoptotic index (r = 0.60, p = 0.004), but not with tumor necrosis (r = 0.22, p = 0.36).Conclusion
Both our in vitro and in vivo findings have shown the ability of [18F]CP18-PET to visualize therapy-induced cancer cell apoptosis and possibly serve as a biomarker for early therapy response.77.
Jaime C. Branco Anabela Barcelos Filipe Pombo de Araújo Graça Sequeira Inês Cunha José Vaz Patto Margarida Oliveira Margarida Pratas Mateus Maura Couto Patrícia Nero Patrícia Pinto Paulo Monteiro Walter Castelão Jorge Félix Diana Ferreira João Almeida Maria João Silva 《Advances in therapy》2016,33(1):46-57
Introduction
Low-dose weekly methotrexate (MTX) is the mainstay in the therapy of rheumatoid arthritis (RA). It can be given via oral, intramuscular or subcutaneous (SC) route. This study sought to determine the real-world pattern of treatment with SC MTX in Portuguese adult patients with active RA.Methods
Utilization of Metoject® in Rheumatoid Arthritis (UMAR) was a non-interventional, cohort multicenter study with retrospective data collection. Eligible patients had active RA, at least 18 years of age, and started SC MTX treatment in 2009 or 2010 after failure or intolerance to oral MTX. Data were collected from patient’s clinical records. Both non-parametric and parametric survival methods were used to obtain a detailed understanding of SC MTX treatment duration.Result
Fifty patients were included, of which only 9 discontinued SC MTX during the study follow-up period. The probability of discontinuation after 1, 2, and 3 years of treatment of SC MTX treatment is expected to be 6.10%, 8.50%, and 23.20%, respectively. The extrapolated median duration of SC MTX using an exponential model was 106.4 months/8.87 years. Mean dose of SC MTX was 18.36 mg. The reasons for treatment discontinuation were occurrence of adverse events in six patients and lack of efficacy in three.Conclusion
The long treatment duration of SC MTX highlights its excellent tolerability compared to oral MTX, especially concerning the frequent adverse gastrointestinal events of MTX. Furthermore, long MTX treatment duration provides the opportunity to postpone or even avoid expensive therapies with biologics. The results obtained from the UMAR study provide important information for the utilization and public financing of SC MTX in Portugal.78.
Cerca N Martins S Cerca F Jefferson KK Pier GB Oliveira R Azeredo J 《The Journal of antimicrobial chemotherapy》2005,56(2):331-336
OBJECTIVES: To quantitatively compare the antibiotic susceptibility of biofilms formed by the coagulase-negative staphylococci (CoNS) Staphylococcus epidermidis and Staphylococcus haemolyticus with the susceptibility of planktonic cultures. METHODS: Several CoNS strains were grown planktonically or as biofilms to determine the effect of the mode of growth on the level of susceptibility to antibiotics with different mechanisms of action. The utility of a new, rapid colorimetric method that is based on the reduction of a tetrazolium salt (XTT) to measure cell viability was tested by comparison with standard bacterial enumeration techniques. A 6 h kinetic study was performed using dicloxacillin, cefazolin, vancomycin, tetracycline and rifampicin at the peak serum concentration of each antibiotic. RESULTS: In planktonic cells, inhibitors of cell wall synthesis were highly effective over a 3 h period. Biofilms were much less susceptible than planktonic cultures to all antibiotics tested, particularly inhibitors of cell wall synthesis. The susceptibility to inhibitors of protein and RNA synthesis was affected by the biofilm phenotype to a lesser degree. Standard bacterial enumeration techniques and the XTT method produced equivalent results both in biofilms and planktonic assays. CONCLUSIONS: This study provides a more accurate comparison between the antibiotic susceptibilities of planktonic versus biofilm populations, because the cell densities in the two populations were similar and because we measured the concentration required to inhibit bacterial metabolism rather than to eradicate the entire bacterial population. While the biofilm phenotype is highly resistant to antibiotics that target cell wall synthesis, it is fairly susceptible to antibiotics that target RNA and protein synthesis. 相似文献
79.
João S. TeodoroAnabela M. Simões Filipe V. DuarteAnabela P. Rolo Richard C. MurdochSaber M. Hussain Carlos M. Palmeira 《Toxicology in vitro》2011,25(3):664-670
The major toxicological concern associated with nanomaterials is the fact that some manufactured nanomaterials are redox active, and some particles transport across cell membranes, especially into mitochondria. Thus, evaluation of their toxicity upon acute exposure is essential. In this work, we evaluated the toxicity of silver nanoparticles (40 and 80 nm) and their effects in rat liver mitochondria bioenergetics.Wistar rat liver mitochondria demonstrate alterations in respiration and membrane potential capacities in the presence of either 40 or 80 nm silver nanoparticles. Our data demonstrated a statistically significant decrease in mitochondrial membrane potential, ADP-induced depolarization, and respiratory control ratio (RCR) upon exposure to silver nanoparticles.Our results show that silver nanoparticles cause impairment of mitochondrial function, due mainly to alterations of mitochondrial membrane permeability. This results in an uncoupling effect on the oxidative phosphorylation system. Thus, mitochondrial toxicity may have a central role in the toxicity resulting from exposure to silver nanoparticles. 相似文献
80.
SP Lopes H Ceri NF Azevedo MO Pereira 《International journal of antimicrobial agents》2012,40(3):260-263
Cystic fibrosis (CF) is a genetic disorder associated with multispecies infections where interactions between classical and newly identified bacteria might be crucial to understanding the persistent colonisation in CF lungs. This study investigated the interactions between two emerging species, Inquilinus limosus and Dolosigranulum pigrum, and the conventional CF pathogen Pseudomonas aeruginosa by evaluating the ability to develop biofilms of mixed populations and then studying their susceptibility patterns to eight different antimicrobials. Monospecies biofilms formed by I. limosus and D. pigrum produced significantly less biomass than P. aeruginosa and displayed greater sensitivity to antimicrobials. However, when in dual-species biofilms with P. aeruginosa, the emerging species I. limosus and D. pigrum were crucial in increasing tolerance of the overall consortia to most antibiotics, even without a change in the number of biofilm-encased cells. These results may suggest that revising these and other species interactions in CF might enable the development of more suitable and effective therapies in the future. 相似文献