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Caroline Louise Diniz Pereira Joelma Carvalho Santos Raissa Melo Arruda Milena Lima Rodrigues Eduardo Sampaio Siqueira Roberto Souza Lemos Andrea Dória Batista Ana Lúcia Coutinho Domingues Edmundo Pessoa Lopes 《Ultrasound in medicine & biology》2021,47(5):1235-1243
In patients with Mansoni schistosomiasis, it is fundamental to evaluate the disease morbidity, which is reflected by the severity of periportal fibrosis (PPF) and parameters of portal hypertension, as analyzed by ultrasonography (US). This study aimed to evaluate the morbidity of schistosomiasis by hepatic and splenic point shear-wave elastography (pSWE) and relate this to US parameters. The PPF pattern, the diameter of the portal and splenic veins and the size of the spleen were evaluated by US. Then, liver and spleen pSWEs were assessed in 74 patients using the same equipment. As the PPF pattern progressed, the splenic pSWE values significantly increased. Significant correlations between splenic pSWE, the longitudinal and transverse lengths of the spleen and the diameters of the portal and splenic veins were observed. These findings, however, were not observed through hepatic pSWE. In conclusion, the splenic pSWE has the potential for assessing morbidity in schistosomiasis mansoni. 相似文献
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Rafaella S. S. Zanette Leonara B. F. de Almeida Nelson L. G. D. Souza Camila G. de Almeida Luiz F. C. de Oliveira Elyabe M. de Matos 《Journal of biomaterials science. Polymer edition》2013,24(16):1489-1504
AbstractCellulose is a renewable polymer quite abundant on the Earth and very attractive for applications in the construction of eco-friendly biomedical products. The aim of this study was to investigate the chemical-physical characteristics of cotton cellulose nanofiber (CCN)/chitosan nanocomposite and its cytocompatibility with human embryonic kidney cells. First, the chemical composition, swelling ratio and surface topography of the nanocomposite were evaluated. Cytocompatibility was then assessed through spreading, proliferation and viability of cells. The experimental results showed that the CCN was an effective nanomaterial agent for increasing the roughness surface of chitosan film. Cell proliferation and changes in cell morphology indicated that the nanocomposite led to improved cell spreading and growth. Cell viability did not decrease after 24?h. However, the cell survival on the nanocomposite was affected at 72?h. The results indicate that CCN/chitosan nanocomposite could be a promising biocompatible biomaterial for biomedical applications. 相似文献
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Beatriz Togoro Ferreira da Silva Livia Tosi Trevelin Ananda Carolina Schroeter Amanda Endres Willers Paulo Francisco Cesar Adriana Bona Matos 《European journal of oral sciences》2021,129(1):e12754
This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented. 相似文献
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Carolina Mayana de Avila Batista Monica Oliveira Piantino Lemos Luis Eduardo de Almeida Prado Franceschi Carolina Borges Basilio Carmelia Matos Santiago Reis 《Anais brasileiros de dermatologia》2014,89(4):671-673
Idiopathic Atrophoderma of Pasini and Pierini (IAPP) is a rare, exclusively
cutaneous disease. It is more frequent in females, with incidence peak in the
second and third decades of life. The etiopathogenesis remains unknown. IAPP
most commonly affects the back, abdomen and proximal regions of the limbs.
Lesions may be rounded, oval or circular; single or multiple. The evolution is
variable and the course is initially progressive. Collagen changes such as
atrophy, thinning, condensation and sclerosis may be observed in the papillary
dermis. This paper describes a case of Idiopathic Atrophoderma of Pasini and
Pierini with histopathologic findings. 相似文献
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Pedro Matos 《Revista portuguesa de cardiologia》2011,30(9):749-751
ObjectivesA proof-of-concept study was undertaken to determine whether differences in corrected coronary opacification (CCO) within coronary lumen can identify arteries with abnormal resting coronary flow.BackgroundAlthough computed tomographic coronary angiography can be used for the detection of obstructive coronary artery disease, it cannot reliably differentiate between anatomical and functional stenoses.MethodsComputed tomographic coronary angiography patients (without history of revascularization, cardiac transplantation, and congenital heart disease) who underwent invasive coronary angiography were enrolled. Attenuation values of coronary lumen were measured before and after stenoses and normalized to the aorta. Changes in CCO were calculated, and CCO differences were compared with severity of coronary stenosis and Thrombolysis In Myocardial Infarction (TIMI) flow at the time of invasive coronary angiography.ResultsOne hundred four coronary arteries (n = 52, mean age = 60.0 ± 9.5 years; men = 71.2%) were assessed. Compared with normal arteries, the CCO differences were greater in arteries with computed tomographic coronary angiography diameter stenoses ≥50%. Similarly, CCO differences were greater in arteries with TIMI flow grade <3 (0.406 ± 0.226) compared with those with normal flow (TIMI flow grade 3) (0.078 ± 0.078, p < 0.001). With CCO differences, abnormal coronary flow (TIMI flow grade < 3) was identified with a sensitivity and specificity, positive predictive value, and negative predictive value of 83.3% (95% confidence interval [CI]: 57.7 to 95.6%), 91.2% (95% CI: 75.2% to 97.7%), 83.3% (95% CI: 57.7% to 95.6%), and 91.2% (95% CI: 75.2% to 97.7%), respectively. Accuracy of this method was 88.5% with very good agreement (kappa = 0.75, 95% CI: 0.55 to 0.94).ConclusionsChanges in CCO across coronary stenoses seem to predict abnormal (TIMI flow grade < 3) resting coronary blood flow. Further studies are needed to understand its incremental diagnostic value and its potential to measure stress coronary blood flow. 相似文献