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111.
Mercedes Villegas Alicia Graciela Cid Cintia Alejandra Briones Analía Irma Romero Florencia Alejandra Pistán Elio Emilio Gonzo Juan Carlos Gottifredi José María Bermúdez 《Saudi Pharmaceutical Journal》2019,27(5):694-701
Controlled drug delivery aims to achieve an effective drug concentration in the action site for a desired period of time, while minimizing side effects. In this contribution, biodegradable poly(3-hydroxybutyrate) films were evaluated as a reservoir platform for dexamethasone controlled release. These systems were morphological and physicochemically characterized. In vitro release assays were performed for five different percentages of drug in the films and data were fitted by a mathematical model developed and validated by our research group. When the profiles were normalized, a single curve properly fitted all the experimental data. Using this unique curve, the dissolution efficiency (DE), the time to release a given amount of drug (tX%), and the mean dissolution time were calculated. Furthermore, the dissolution rate, the initial dissolution rate (a%) and the intrinsic dissolution rate were determined. The a% mean value was 1.968 × 10?2% released/min, t80% was about 14 days, and the DE was 59.6% at 14 days and 66.5% at 20 days. After 2 days, when approximately 40% of the drug was released, the dissolution rate decreased about 60% respect to the initial value. The poly(3-hydroxybutyrate) platforms behaved as an appropriate system to release and control the dexamethasone delivery, suggesting that they could be an alternative to improve drug therapy. 相似文献
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María Rosa Güell Rous Salvador Díaz Lobato Gema Rodríguez Trigo Fátima Morante Vélez Marta San Miguel Pilar Cejudo Francisco Ortega Ruiz Alejandro Muñoz Juan Bautista Galdiz Iturri Almudena García Emilio Servera 《Archivos de bronconeumología》2014
Pulmonary rehabilitation (PR) has been shown to improve dyspnea, exercise capacity and health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). PR has also shown benefits in diseases other than COPD but the level of evidence is lower. The fundamental components of PR programs are muscle training, education and chest physiotherapy. Occupational therapy, psychosocial support and nutritional intervention should also be considered. Home programs have been shown to be as effective as hospital therapy. The duration of rehabilitation programs should not be less than 8 weeks or 20 sessions. Early initiation of PR, even during exacerbations, has proven safe and effective. The use of oxygen or noninvasive ventilation during training is controversial and dependent on the patient's situation. At present, the best strategy for maintaining the benefits of PR in the long term is unknown. Longer PR programs or telemedicine could play a key role in extending the results obtained. 相似文献
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Flavio D'Ascenzi MD PhD Francesca Anselmi MD Paolo Emilio Adami MD Antonio Pelliccia MD 《Clinical cardiology》2020,43(8):827-833
The presence of T-wave inversion (TWI) at 12-lead electrocardiogram (ECG) in competitive athletes is one of the major diagnostic challenges for sports physicians and consulting cardiologists. Indeed, while the presence of TWI may be associated with some benign conditions and it may be occasionally seen in healthy athletes presenting signs of cardiac remodeling, it may also represent an early sign of an underlying, concealed structural heart disease or life-threatening arrhythmogenic cardiomyopathies, which may be responsible for exercise-related sudden cardiac death (SCD). The interpretation of TWI in athletes is complex and the inherent implications for the clinical practice represent a conundrum for physicians. Accordingly, the detection of TWI should be viewed as a potential red flag on the ECG of young and apparently healthy athletes and warrants further investigations because it may represent the initial expression of cardiomyopathies that may not be evident until many years later and that may ultimately be associated with adverse outcomes. The aim of this review is, therefore, to report an update of the literature on TWI in athletes, with a specific focus on the interpretation and management. 相似文献
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Monasterio Gustavo Guevara José Ibarra Juan Pablo Castillo Francisca Díaz-Zúñiga Jaime Alvarez Carla Cafferata Emilio A. Vernal Rolando 《Clinical oral investigations》2019,23(4):1887-1894
Clinical Oral Investigations - Periodontitis is a chronic inflammatory disease characterized by tooth-supporting tissue destruction, which is elicited by the host’s immune response triggered... 相似文献
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Annamaria Perna Immacolata Intaglietta Amalia Simonetti Emilio Gambacorta 《Bulletin of environmental contamination and toxicology》2014,92(3):253-258
The aim of the study was to quantify the cadmium (Cd), lead (Pb), chromium (Cr) and arsenic (As) contents in ninety honey samples from nine areas of southern Italy. Results showed that As content was below the detection limit, while Cd, Pb, and Cr contents were below the recommended maximum acceptable levels. Mean Cd, Pb, and Cr contents were 0.013, 0.289 and 0.707 mg kg?1, respectively. The metal contents in honey varied greatly depending on considered area. Correlations between the metals were statistically significant (p < 0.05), suggesting that polluting sources involve the simultaneous presence of metals in honey. 相似文献
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Carlos Pérez García-Pando Michelle C. Stanton Peter J. Diggle Sylwia Trzaska Ron L. Miller Jan P. Perlwitz José M. Baldasano Emilio Cuevas Pietro Ceccato Pascal Yaka Madeleine C. Thomson 《Environmental health perspectives》2014,122(7):679-686
Background: Epidemics of meningococcal meningitis are concentrated in sub-Saharan Africa during the dry season, a period when the region is affected by the Harmattan, a dry and dusty northeasterly trade wind blowing from the Sahara into the Gulf of Guinea.Objectives: We examined the potential of climate-based statistical forecasting models to predict seasonal incidence of meningitis in Niger at both the national and district levels.Data and methods: We used time series of meningitis incidence from 1986 through 2006 for 38 districts in Niger. We tested models based on data that would be readily available in an operational framework, such as climate and dust, population, and the incidence of early cases before the onset of the meningitis season in January–May. Incidence was used as a proxy for immunological state, susceptibility, and carriage in the population. We compared a range of negative binomial generalized linear models fitted to the meningitis data.Results: At the national level, a model using early incidence in December and averaged November–December zonal wind provided the best fit (pseudo-R2 = 0.57), with zonal wind having the greatest impact. A model with surface dust concentration as a predictive variable performed indistinguishably well. At the district level, the best spatiotemporal model included zonal wind, dust concentration, early incidence in December, and population density (pseudo-R2 = 0.41).Conclusions: We showed that wind and dust information and incidence in the early dry season predict part of the year-to-year variability of the seasonal incidence of meningitis at both national and district levels in Niger. Models of this form could provide an early-season alert that wind, dust, and other conditions are potentially conducive to an epidemic.Citation: Pérez García-Pando C, Stanton MC, Diggle PJ, Trzaska S, Miller RL, Perlwitz JP, Baldasano JM, Cuevas E, Ceccato P, Yaka P, Thomson MC. 2014. Soil dust aerosols and wind as predictors of seasonal meningitis incidence in Niger. Environ Health Perspect 122:679–686; http://dx.doi.org/10.1289/ehp.1306640 相似文献
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