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101.
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Xiaohong Wang George Huyang Sri Vikram Palagummi Xiaohui Liu Drago Skrtic Carlos Beauchamp Rafael Bowen Jirun Sun 《Dental materials》2018,34(2):228-237
Objective
The objectives of this project were to: 1) develop strong and durable dental resin composites by employing new monomers that are hydrolytically stable, and 2) demonstrate that resin composites based on these monomers perform superiorly to the traditional bisphenol A glycidyl dimethacrylate/triethylene glycol dimethacrylate (Bis-GMA/TEGDMA) composites under testing conditions relevant to clinical applications.Methods
New resins comprising hydrolytically stable, ether-based monomer, i.e., triethylene glycol divinylbenzyl ether (TEG-DVBE), and urethane dimethacrylate (UDMA) were produced via composition-controlled photo-polymerization. Their composites contained 67.5 wt% of micro and 7.5 wt% of nano-sized filler. The performances of both copolymers and composites were evaluated by a battery of clinically-relevant assessments: degree of vinyl conversion (DC: FTIR and NIR spectroscopy); refractive index (n: optical microscopy); elastic modulus (E), flexural strength (F) and fracture toughness (KIC) (universal mechanical testing); Knoop hardness (HK; indentation); water sorption (Wsp) and solubility (Wsu) (gravimetry); polymerization shrinkage (Sv; mercury dilatometry) and polymerization stress (tensometer). The experimental UDMA/TEG-DVBE composites were compared with the Bis-GMA/TEGDMA composites containing the identical filler contents, and with the commercial micro hybrid flowable composite.Results
UDMA/TEG-DBVE composites exhibited n, E, Wsp, Wsu and Sv equivalent to the controls. They outperformed the controls with respect to F (up to 26.8% increase), KIC (up to 27.7% increase), modulus recovery upon water sorption (full recovery vs. 91.9% recovery), and stress formation (up to 52.7% reduction). In addition, new composites showed up to 27.7% increase in attainable DC compared to the traditional composites. Bis-GMA/TEGDMA controls exceeded the experimental composites with respect to only one property, the composite hardness. Significantly, up to 18.1% lower HK values in the experimental series (0.458 GPa) were still above the clinically required threshold of approx. 0.4 GPa.Significance
Hydrolytic stability, composition-controlled polymerization and the overall enhancement in clinically-relevant properties of the new resin composites make them viable candidates to replace traditional resin composites as a new generation of strong and durable dental restoratives. 相似文献104.
Vacante Marco DAgata Velia Motta Massimo Malaguarnera Giulia Biondi Antonio Basile Francesco Malaguarnera Michele Gagliano Caterina Drago Filippo Salamone Salvatore 《BMC surgery》2012,12(1):1-8
Background
Five percent of all patients with breast cancer have distant metastatic disease at initial presentation. Because metastatic breast cancer is considered to be an incurable disease, it is generally treated with a palliative intent. Recent non-randomized studies have demonstrated that (complete) resection of the primary tumor is associated with a significant improvement of the survival of patients with primary metastatic breast cancer. However, other studies have suggested that the claimed survival benefit by surgery may be caused by selection bias. Therefore, a randomized controlled trial will be performed to assess whether breast surgery in patients with primary distant metastatic breast cancer will improve the prognosis.Design
Randomization will take place after the diagnosis of primary distant metastatic breast cancer. Patients will either be randomized to up front surgery of the breast tumor followed by systemic therapy or to systemic therapy, followed by delayed local treatment of the breast tumor if clinically indicated. Patients with primary distant metastatic breast cancer, with no prior treatment of the breast cancer, who are 18 years or older and fit enough to undergo surgery and systemic therapy are eligible. Important exclusion criteria are: prior invasive breast cancer, surgical treatment or radiotherapy of this breast tumor before randomization, irresectable T4 tumor and synchronous bilateral breast cancer. The primary endpoint is 2-year survival. Quality of life and local tumor control are among the secondary endpoints. Based on the results of prior research it was calculated that 258 patients are needed in each treatment arm, assuming a power of 80%. Total accrual time is expected to take 60 months. An interim analysis will be performed to assess any clinically significant safety concerns and to determine whether there is evidence that up front surgery is clinically or statistically inferior to systemic therapy with respect to the primary endpoint.Discussion
The SUBMIT study is a randomized controlled trial that will provide evidence on whether or not surgery of the primary tumor in breast cancer patients with metastatic disease at initial presentation results in an improved survival.Trial registration
NCT01392586. 相似文献105.
Left atrial (LA) strain and strain rate, determined by speckle-tracking echocardiography (STE), are reproducible indices to assess LA function. Different normal ranges for LA phasic functions have been reported. We investigated the role of the reference point (P- and R-wave), gain, and region of interest (ROI), as the major sources of variation when assessing LA function. 52 subjects were evaluated for LA conventional and STE analysis. 45 of them (46 ± 14 years, 26 men) were feasible for concomitant LA deformation, and LA phasic volumes and ejection fractions (LAEF) evaluation. First, we compared the P- and R-wave methods, for the evaluation of the LA functions. We used diastolic mitral profile to clearly delineate the time intervals for each LA function. For the P-wave method, active function was assessed from negative global strain as a difference between the strain at pre-atrial contraction and strain just before mitral valve closure (GSA-), and late diastolic strain rate (GSRL); passive function from positive strain at MVO (GSA+), and from early negative diastolic strain rate (GSRE); reservoir function from the sum of GSA? and GSA+ (TGSA), and positive strain rate at the beginning of LV systole (GSR+). For the R-wave method we used the same SR parameters. The active function was evaluated by late positive global strain (GSAC), the reservoir by positive peak before the opening of the mitral valve (TGSA), and conduit function by the difference between TGSA and GSAC (GSA+). Then, by using P-wave method, we measured all previously described parameters for different gains—minimum (G0), medium (G12), and maximum (G24), and for different ROIs—minimum (ROI0), step 1 (ROI1), and 2 (ROI2). Feasibility of the LA strain measurements was 87 %. Active LA function was similar in the absolute value (GSAC and GSA?), whereas passive and reservoir functions were significantly higher (GSA+, TGSA) with the R-wave method. Active LAEF correlated with GSA? measured by the P-wave (r = ?0.44, p = 0.002), but not with the GSAC measured by the R-wave method. Similar correlations were found for passive and reservoir LAEF with correspondent strain parameters, only with P-wave method. There were no differences between methods regarding SR indices and their correlations with correspondent LAEFs. Increase of gain from minimum to maximum overestimated all measured LA functions (all p < 0.05). Intermediary changes did not have a significant impact on the measurement of active and conduit function, but they do have on the measurement of the reservoir function. Increase of ROI from minimum to ROI2 was associated with an overestimation of all measurements of atrial functions (all p < 0.05). For all parameters, except GSR+, a decrease of atrial S and SR values from minimum ROI to step 1 was recorded. For GSA+, TGSA, GSRE a decrease of S and SR values with each ROI step was recorded. The two methods used to assess LA functions by STE do not provide similar results. The R-wave method essentially ignores negative peak, creating a positive strain for atrial contraction, and also provides higher values for the reservoir and conduit functions, by comparison with the P-wave method. Increase of gain overestimates, whereas increase of ROI underestimates all parameters of LA functions. Therefore, we suggest that P-wave as a reference point, a medium gain, and a minimum ROI should be used as the best choice for a correct assessment. 相似文献
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Federico Tremolada Carla Casarin Alfredo Alberti Claudio Drago Alessandro Tagger Maria Luisa Ribero Giuseppe Realdi 《Journal of hepatology》1992,16(3)
One hundred and thirty-five patients who developed non-A, non-B post-transfusion hepatitis mostly after cardiac surgery, were followed for a mean (±S.D.) of 90±41 months (range: 13–180) to evaluate clinical and histological outcome.Thirty-one cases resolved within 12 months, while 104 (77%) progressed to chronicity. Twenty-one of 65 (32%) biopsied patients developed cirrhosis at the end of the follow-up, and one further progressed to hepatocellular carcinoma. One patient had a complete histological remission (1%). The remaining cases had chronic active (37%), chronic persistent (27%) or chronic lobular hepatitis (3%). About half of the cases with cirrhosis developed portal hypertension, and three of these died due to esophageal varices hemorrhage, one due to liver failure, and one due to hepatocellular carcinoma. Out of 26 patients with the initial histologic diagnosis of chronic hepatitis that were rebiopsied during follow-up, 13 (50%) progressed to cirrhosis. These patients were significantly older than patients who did not develop cirrhosis (mean age 57 and 45 years respectively; p<0.01).During acute hepatitis anti-HCV was positive in all but one of the 114 patients tested. Percentages were similar for patients who recovered (95%) and those who developed chronic hepatitis (100%). However, during follow-up, 71% of the 1st generation and 21% of the 2nd generation ELISA test patients with acute resolved hepatitis became anti-HCV negative, while the same figures in chronic cases were only 8.5% (p<0.0001) and 1.4% (p=0.012). This suggests a correlation between anti-HCV antibody activity, hepatitis C virus replication, and the development of chronic liver disease. 相似文献
108.
Giaquinto C Callegaro S Andreola B Bernuzzi M Cantarutti L D'Elia R Drago S De Marchi A Falconi P Felice M Giancola G Lista C Manni C Perin M Pisetta F Scamarcia A Sidran MP Da Dalt L 《Infection》2008,36(4):351-357
BACKGROUND: : Data on the burden of rotavirus gastroenteritis in Europe are needed to help understand the potential impact of introducing new rotavirus vaccines. MATERIALS AND METHODS: : As part of prospective observational study (Rotavirus gastroenteritis Epidemiology and Viral types in Europe Accounting for Losses in Public Health and Society Study, REVEAL) conducted in 2004-2005 in seven European countries, we studied, the characteristics of acute gastroenteritis and rotavirus gastroenteritis in children less than 5 years in primary care, emergency room and hospital settings (Padova, Italy). RESULTS: : A total of 757 children with acute gastroenteritis were included and enzyme-linked immunoabsorbent assay (ELISA) results were available for 725 cases. The overall estimated annual incidence for rotavirus gastroenteritis was 4.7%. Overall, rotavirus gastroenteritis was estimated to account for 43.6% of acute gastroenteritis cases. Among children with acute gastroenteritis (AGE) aged 6-23 months, 61.2% were rotavirus positive. Rotavirus gastroenteritis (RVGE) was responsible for 68.8% of hospitalizations, 61% of emergency consultations, and 33% of primary care consultations. The most prevalent serotype was G9 (84.4%) followed by G1 (11.8%). The relative risk for rotavirus gastroenteritis of being referred to hospital after an initial consultation in primary care was 3.37 (95% CI: 1.77-6.43) and 3.38 (95% CI: 2.28-5.01) for emergency room referral. Children with rotavirus gastroenteritis generally had more severe disease than children with rotavirus-negative gastroenteritis. CONCLUSION: : Rotavirus accounts for a significant proportion of acute gastroenteritis cases in children less than 5 years in Italy, many of whom require frequent primary care consultations, or care in emergency room or hospital settings. 相似文献
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110.
Drago L Romanò CL Mattina R Signori V De Vecchi E 《Clinical orthopaedics and related research》2012,470(10):2915-2925