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991.
《Journal of the American College of Radiology》2018,15(10):1458-1463
PurposeThe aim of this study is to determine the impact of a simulation-based ultrasound-guided (USG) breast biopsy training session on radiology trainee procedural knowledge, comfort levels, and overall procedural confidence and anxiety.MethodsTwenty-one diagnostic radiology residents from a single academic institution were recruited to participate in an USG breast biopsy training session. The residents filled out a questionnaire before and after the training session. Ten multiple-choice questions tested general knowledge in diagnostic breast ultrasound and USG breast biopsy concepts. Subjective comfort levels with ultrasound machine and biopsy device functionality, patient positioning, proper biopsy technique, image documentation, needle safety and overall procedural confidence and anxiety levels were reported on a 5-point Likert scale before and after training.ResultsParticipants demonstrated significant improvement in number of correctly answered general knowledge questions after training (P < .0001). Significant improvement was seen in resident comfort level in ultrasound machine functionality, patient positioning, biopsy device functionality, biopsy technique, image documentation, as well as overall confidence level (all P < .05). Participants indicated a slight but not significant reduction in anxiety levels (P = .27).ConclusionsA simulation-based USG breast biopsy training session may improve radiology trainee procedural knowledge, comfort levels, and overall procedural confidence. 相似文献
992.
Roberto M. Lang Karima Addetia Akhil Narang Victor Mor-Avi 《JACC: Cardiovascular Imaging》2018,11(12):1854-1878
The ongoing refinements in 3-dimensional (3D) echocardiography technology continue to expand the scope of this imaging modality in clinical cardiology by offering new features that stem from the ability to image the heart in its complete dimensionality. Over the years, countless publications have described these benefits and tested new frontiers where 3D echocardiographic imaging seemed to offer promising ways to improve patients’ care. These include improved techniques for chamber quantification and novel ways to visualize cardiac valves, including 3D printing, virtual reality, and holography. The aims of this review article are to focus on the most important developments in the field in the recent years, discuss the current utility of 3D echocardiography, and highlight several interesting future directions. 相似文献
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994.
Alexander Grimm Hubertus Axer Bianka Heiling Natalie Winter 《Clinical neurophysiology》2018,129(7):1403-1409
Objective
Reference values are crucial for nerve ultrasound. Here, we reevaluated normal nerve and fascicle cross-sectional area (CSA) values in humans and compared them to published values. Based on these data, ultrasound pattern sum score (UPSS) boundary values were revisited and readjusted.Methods
Ultrasound of different peripheral nerves was performed in 100 healthy subjects at anatomically defined landmarks. Correlations with age, gender, height and weight were calculated.Results
Overall, correspondence to other published reference values was high. Gender-dependency was found for the proximal median nerve. Dependency from height occurred in the tibial nerve (TN). Weight-dependency was not found. However, the most obvious differences were found in the TN between men >60?years and women <60?years. Thus, general boundary values were defined using the mean plus the twofold standard deviation for all subjects and nerve segments except for the TN, in which different cut-offs were proposed for elder men. Accordingly, the cut-offs for the UPSS were re-adjusted, none of the individuals revealed more than 2 points at maximum.Conclusions
The influence of distinct epidemiological factors on nerve size is most prominent in the TN, for which thus several normal values are useful.Significance
Adjusted reference values improve the accuracy of the UPSS. 相似文献995.
996.
Christopher J. Moore Melissa C. Caughey Diane O. Meyer Regina Emmett Catherine Jacobs Manisha Chopra James F. Howard Caterina M. Gallippi 《Ultrasound in medicine & biology》2018,44(12):2519-2530
Our group has previously found that in silico, mechanical anisotropy may be interrogated by exciting transversely isotropic materials with geometrically asymmetric acoustic radiation force excitations and then monitoring the associated induced displacements in the region of excitation. We now translate acoustic radiation force-based anisotropy assessment to human muscle in vivo and investigate its clinical relevance to monitoring muscle degeneration in Duchenne muscular dystrophy (DMD). Clinical anisotropy assessments were performed using Viscoelastic Response ultrasound, with a degree of anisotropy reflected by the ratios of Viscoelastic Response relative elasticity (RE) or relative viscosity (RV) measured with the asymmetric radiation force oriented parallel versus perpendicular to muscle fiber alignment. In vivo results from rectus femoris and gastrocnemius muscles of boys aged ~7.9–10.4 y indicate that RE and RV anisotropy ratios in rectus femoris muscles of boys with DMD were significantly higher than those of healthy control boys (RE: DMD?=?1.51 ± 0.87, control?=?0.99 ± 0.69, p?=?0.04, Wilcoxon rank sum test; RV: DMD?=?1.04 ± 0.71, control?=?0.74 ± 0.22, p?=?0.02). In the gastrocnemius muscle, only the RV anisotropy ratio was significantly higher in dystrophic than control patients (DMD?=?1.23 ± 0.35, control?=?0.88 ± 0.31, p?=?0.04). In the dystrophic rectus femoris muscle, the RE anisotropy ratio was inversely correlated (slope?=?–0.03/lbf, r?=?–0.43, p?=?0.07, Pearson correlation) with quantitative muscle testing functional output measures but was not correlated with quantitative muscle testing in the dystrophic gastrocnemius. These results suggest that Viscoelastic Response RE and RV measures reflect differences in mechanical anisotropy associated with functional impairment with dystrophic degeneration that are relevant to monitoring DMD clinically. 相似文献
997.
998.
999.
Dong Hyo Noh Kyu Choi Seonhye Gu Juhee Cho Kee-Taek Jang Young Sik Woo 《Scandinavian journal of gastroenterology》2018,53(1):94-99
Background: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is effective for tissue diagnosis of pancreatic mass. To improve diagnostic yield and drawbacks, 22-gauge (G) core biopsy (FNB) needle has been developed. This study aims to compare 22G FNA and FNB needles for EUS-guided sampling of suspected pancreatic cancer.Methods: This is a randomized controlled crossover trial. A total of 60 patients with suspected unresectable pancreatic cancer referred for EUS-guided sampling were randomly assigned to two groups. Both groups had 22G FNA and FNB needles performed in a randomized order. The primary endpoint was the cytological, histological and overall diagnostic accuracy of pancreatic cancer.Results: FNA and FNB needles reported similar level of diagnostic accuracy (FNA needle 95% vs. FNB needle 93.3%; p?=?.564), and it was not statistically different. However, cytological cellularity was significantly higher in the FNB needles compared to FNA needles (odds ratio 2.75, 95% confidence interval (CI)). There were no procedure-related complications in both needles.Conclusions: The diagnostic accuracy of EUS-guided sampling for pancreatic cancer using 22G FNA is comparable to FNB needles. The cytological quality of specimen is better in the FNB needle. 相似文献
1000.