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101.
102.
Banar Nikolay Bertels Jeroen Laurent François Boedi Rizky Merdietio De Tobel Jannick Thevissen Patrick Vandermeulen Dirk 《International journal of legal medicine》2020,134(5):1831-1841
International Journal of Legal Medicine - Staging third molar development is commonly used for age assessment in sub-adults. Current staging techniques are, at most, semi-automated and rely on... 相似文献
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104.
Sex‐specific extent and severity of white matter damage in multiple sclerosis: Implications for cognitive decline 下载免费PDF全文
Menno M. Schoonheim René M. Vigeveno Fernanda C. Rueda Lopes Petra J.W. Pouwels Chris H. Polman Frederik Barkhof Jeroen J.G. Geurts 《Human brain mapping》2014,35(5):2348-2358
Cognitive dysfunction is common in multiple sclerosis (MS). However, the relationship between white matter (WM) damage and cognition remains insufficiently clear. This study investigates the extent and severity of WM diffusion abnormalities in MS patients and relations with cognition. Diffusion tensor imaging scans were obtained in 131 MS patients (88 women, 6 years postdiagnosis) and 49 age‐matched controls (29 women). Patient groups were equal in terms of disease duration, disability, and WM lesion volume. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between groups. Post hoc analyses calculated the spatial extent and severity of diffusion abnormalities to relate these to cognitive performance. In controls, 31% of WM voxels showed higher FA in men; therefore, all patient analyses were within‐sex. The extent of diffusion changes was higher in male patients than in female patients for all parameters (FA: 24% in women, 53% in men), as was the severity of changes (FA: Z = ?0.18 in women, Z = ?0.41 in men). Especially the extent of FA abnormalities was strongly related to cognitive performance in all patients (r = ?0.42, P < 0.0001). Regionally, thalamic decreases in FA were especially correlated with cognitive performance. Cognitively impaired patients showed greater extent and severity on all diffusion parameters compared to cognitively preserved patients. The WM of male patients was both more extensively and also more severely affected than that of female patients. The extent of WM FA changes, especially in the thalamus, was associated with cognitive performance in this cohort of early MS patients. Hum Brain Mapp 35:2348–2358, 2014. © 2013 Wiley Periodicals, Inc . 相似文献
105.
Prejaas Tewarie Martijn D. Steenwijk Betty M. Tijms Marita Daams Lisanne J. Balk Cornelis J. Stam Bernard M.J. Uitdehaag Chris H. Polman Jeroen J.G. Geurts Frederik Barkhof Petra J.W. Pouwels Hugo Vrenken Arjan Hillebrand 《Human brain mapping》2014,35(12):5946-5961
Both gray matter atrophy and disruption of functional networks are important predictors for physical disability and cognitive impairment in multiple sclerosis (MS), yet their relationship is poorly understood. Graph theory provides a modality invariant framework to analyze patterns of gray matter morphology and functional coactivation. We investigated, how gray matter and functional networks were affected within the same MS sample and examined their interrelationship. Magnetic resonance imaging and magnetoencephalography (MEG) were performed in 102 MS patients and 42 healthy controls. Gray matter networks were computed at the group‐level based on cortical thickness correlations between 78 regions across subjects. MEG functional networks were computed at the subject level based on the phase‐lag index between time‐series of regions in source‐space. In MS patients, we found a more regular network organization for structural covariance networks and for functional networks in the theta band, whereas we found a more random network organization for functional networks in the alpha2 band. Correlation analysis revealed a positive association between covariation in thickness and functional connectivity in especially the theta band in MS patients, and these results could not be explained by simple regional gray matter thickness measurements. This study is a first multimodal graph analysis in a sample of MS patients, and our results suggest that a disruption of gray matter network topology is important to understand alterations in functional connectivity in MS as regional gray matter fails to take into account the inherent connectivity structure of the brain. Hum Brain Mapp 35:5946–5961, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
106.
Susanne J van Veluw Wilmar M T Jolink Jeroen Hendrikse Mirjam I Geerlings Peter R Luijten Geert Jan Biessels Catharina J M Klijn 《Journal of cerebral blood flow and metabolism》2014,34(7):1104-1106
In patients with spontaneous intracerebral hemorrhage (ICH) coexisting abnormalities on brain imaging can provide clues on the etiology of the underlying small vessel disease. We examined cortical cerebral microinfarcts as a novel marker of coexistent vascular damage in ICH. Twelve patients with spontaneous ICH and 15 controls underwent 7Tesla magnetic resonance imaging (MRI). Microinfarcts were present in 9 of 12 patients with spontaneous ICH, and in 5 of 15 controls. This explorative study shows, for the first time, that microinfarcts appear to be a very common vascular comorbidity in spontaneous ICH. Future larger studies should further assess the etiological significance of these lesions. 相似文献
107.
Jeroen E. H. Ponten Irene Thomassen Simon W. Nienhuijs 《The Indian journal of surgery》2014,76(5):371-377
In accordance with the tension-free principles for other hernias, umbilical and epigastric hernia repair should probably be mesh-based. The number of randomized studies is increasing, most of them showing significantly less recurrences with the use of a mesh. Different devices are available and are applicable by several approaches. The objective of this review was to evaluate recent literature for the different types of mesh for umbilical and epigastric hernia repair and recurrences after mesh repair. A multi-database search was conducted to reveal relevant studies since 2001 reporting mesh-based repair of primary umbilical/epigastric hernia and their outcomes in adult patients. A total of 20 studies were included, 15 of them solely involved umbilical hernias, whereas the remaining studies included epigastric hernias as well. A median of 124 patients (range, 17–384) was investigated per study. Three quarters of the included studies had a follow-up of at least 2 years. Six studies described the results of laparoscopic approach, of which one reported a recurrence rate of 2.7 %; in the remaining studies, no recurrences occurred. Two comparative studies reported a lower incidence of complications and postoperative pain after laparoscopic repair compared to open repair. Seventeen studies reported results of open techniques, of which seven studies showed no recurrence. Other studies reported recurrence rates up to 3.1 %. A wide range of complication rates were reported (0–33 %). This collective review showed acceptable recurrence rates for mesh-based umbilical and epigastric hernia repair. A wide range of devices was investigated. A tendency toward more complications after laparoscopic repair was found compared to open repair. 相似文献
108.
Background
Flexible endoscopes are increasingly used to perform advanced intraluminal and transluminal interventions. These complex interventions demand accurate and efficient control, however, current endoscopes lack intuitiveness and ergonomic control of the endoscope tip. Alternative handheld controllers can improve intuitiveness and ergonomics, though previous studies are inconclusive concerning their effect on the efficiency of endoscope manipulation. The aim of this study is to determine the efficiency of a robotic system with intuitive user interface in controlling the tip of the flexible endoscope.Methods
We compared the efficiency of time and tip trajectory when steering the endoscope tip using the conventional steering wheels and a robotic platform with three different user interfaces: a touchpad in combination with a position control algorithm, a joystick combined with linear rate control, and a joystick combined with non-linear rate control. Fourteen participants, without a medical background, used all four interfaces. They performed both large navigational and fine targeting tasks in a simulated environment which allowed objective cross-subject comparison. Afterward, the participants were asked to select their preferred steering method.Results
Participants were significantly faster in steering the endoscope tip when using robotic steering compared to using the conventional steering method. Between the robotic interfaces, using the touchpad was significantly faster compared to the joystick with linear rate control. Use of the joystick with non-linear rate control led to a shorter tip trajectory compared to the touchpad. The majority of participants preferred the joystick with non-linear rate control over the other steering methods.Conclusions
This work shows that intuitive user interfaces can improve the efficiency of endoscope tip steering. 相似文献109.
Sabrina L. Lince Leon C. van Kempen Jeroen R. Dijkstra Joanna IntHout Mark E. Vierhout Kirsten B. Kluivers 《International urogynecology journal》2014,25(9):1237-1242