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Yasuhiro Yoshiga Akihiko Shimizu Toshihiko Yamagata Masahiro Esato Takeshi Ueyama Masato Ohmura Kazuo Itagaki Masayasu Kimura Hiroyuki Kakugawa Masahiro Doi Masunori Matsuzaki 《Circulation journal》2003,67(5):437-442
The aims of this study were to evaluate the changes in the electrophysiological characteristics of the right atrium after the administration of flecainide and to clarify whether flecainide has a selective effect on human atrial tissue. Electrophysiological measurements were made in 38 patients, before and after intravenous administration of flecainide (2 mg/kg per 10 min). The effective refractory period of the right atrium (ERP-A), maximum conduction delay (Max.CD), repetitive atrial firing zone (RAFZ), fragmented atrial activity zone (FAAZ), and conduction delay zone (CDZ) were studied in the patients who were divided into 2 groups based on whether repetitive atrial firing (RAF) was induced in the baseline study. Flecainide significantly prolonged the ERP-A (202+/-22 to 238+/-33 ms, p<0.001) and shortened Max.CD (77+/-17 to 63+/-32 ms, p<0.05) in the patients with RAF, but not in those without RAF in the baseline study. After flecainide administration, there were significant reductions in the RAFZ (43+/-22 to 13+/-19 ms, p<0.0001), FAAZ (51+/-22 to 28+/-26 ms, p<0.001) and CDZ (70+/-21 to 48+/-30 ms, p<0.01) in the patients with RAF. However, atrial fibrillation (AF) was induced by stimulation after flecainide in 2 patients without RAF in the baseline study. There was a significant negative correlation between the ERP-A in the baseline study and the change in the ERP-A upon flecainide administration (r=0.45, p<0.01). Flecainide may preferentially activate the substrate for AF and RAF, but that action is mainly based on the electrophysiological characteristics found in the baseline study. 相似文献
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Maeda S Iesaka Y Uno K Otomo K Nagata Y Suzuki K Hachiya H Goya M Takahashi A Fujiwara H Hiraoka M Isobe M 《Heart and vessels》2012,27(1):58-64
Few studies have explored the topographic anatomy of the esophagus, posterior wall of the left atrium (LA), or fat pads using multidetector computed tomography (MDCT) to prevent the risk of esophageal injury during atrial fibrillation (AF) ablation. MDCT was performed in 110 consecutive patients with paroxysmal or persistent AF before the ablation procedure to understand the anatomic relationship of the esophagus. Two major types of esophagus routes were demonstrated. Leftward (type A) and rightward (type B) routes were found in 90 and 10% of the patients, respectively. A type A route had a larger mean size of the LA than type B. The fat pad was identifiable at the level of the inferior pulmonary vein in 91% of the patients without any predominance of either type. The thickness of the fat pad was thinner in the patients with a dilated LA (>42?mm) than in those with a normal LA size (??42?mm) (p?=?0.01). The results demonstrated that the majority of cases had a leftward route of the esophagus. There was a close association between the LA dilatation and fat pad thinning. With a dilated LA, the esophagus may become easily susceptible to direct thermal injury during AF ablation. Visualization of the anatomic relationship may contribute to the prevention of the potential risk of an esophageal injury. 相似文献
45.
Katsunori Iijima Nobuyuki Ara Yasuhiko Abe Tomoyuki Koike Toshimitsu Iwabuchi Hirohiko Shinkai Kaname Uno Hiroyuki Endo Naoki Asano Tooru Shimosegawa 《Journal of gastroenterology》2012,47(12):1290-1297
Background
The association of Helicobacter pylori infection with aspirin-induced gastropathy is controversial. H. pylori infection exerts diverse effects on gastric acid secretion. In this study, the interaction between H. pylori infection and aspirin was investigated with reference to the individual gastric acid secretion level in H. pylori-positive subjects.Methods
Ninety-three (81 men, mean age: 70?years) long-term low-dose aspirin takers were prospectively enrolled. H. pylori infection was evaluated by serum IgG antibody determination, and gastrin-stimulated acid output was assessed with the endoscopic gastrin test. H. pylori-positive aspirin-takers were classified into 2 subgroups (hyposecretors and non-hyposecretors). The grade of gastric mucosal injury was assessed endoscopically according to the modified Lanza score; intensive aspirin-induced gastropathy was defined as a modified Lanza score of ??4. Multiple logistic regression analyses were used to adjust for potential confounders.Results
With H. pylori-negative patients taken as the reference, H. pylori infection was found to be positively associated with intensive gastropathy among non-hyposecretors, with an odds ratio (OR) (95?% confidence interval [CI]) of 4.2 (1.1?C17.1), while the infection was negatively associated with gastropathy among hyposecretors, with an OR (95?% CI) of 0.3 (0.08?C0.9). Aspirin-induced gastropathy occurred preferentially in the antrum among H. pylori-positive non-hyposecretors, while it affected the fundus among H. pylori-positive hyposecretors.Conclusion
The effect of H. pylori infection on the aspirin-induced gastropathy was biphasic depending on the individual gastric acid secretion level. In the presence of sufficient amounts of gastric acid, H. pylori infection and aspirin could synergistically damage gastric mucosal integrity, while in the absence of sufficient amounts of gastric acid, the synergistic effect could be completely counteracted and the infection could even suppress the aspirin-induced gastropathy. 相似文献46.
Domei T Yokoi H Kuramitsu S Soga Y Arita T Ando K Shirai S Kondo K Sakai K Goya M Iwabuchi M Ueeda M Nobuyoshi M 《Circulation journal》2012,76(2):423-429
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49.
Tomoyuki Kono Toshiho Ohtsuki Naohisa Hosomi Ikuko Takeda Shiro Aoki Yoshimasa Sueda Kayoko Ishihara Takeshi Nakamura Takemori Yamawaki Masayasu Matsumoto 《Geriatrics & Gerontology International》2012,12(3):468-474
Aim: Although several studies have reported various causes of ischemic stroke in patients with cancer, only a few have evaluated the clinical relevance of ischemic stroke pathogenesis to cancer. The aim of the present study was to elucidate the clinical characteristics of cancer‐associated ischemic stroke. Methods: We evaluated 154 ischemic stroke patients without cancer and 57 ischemic stroke patients with cancer who had either received continuous treatment for cancer within 5 years before to the onset of ischemic stroke, or who had been diagnosed with cancer within 1 year after the onset of ischemic stroke. Cancer patients were grouped into “cancer‐associated ischemic stroke,” the “conventional ischemic stroke,” or “other.” Results: A total of 15 patients (26%) were classified into the cancer‐associated ischemic stroke in cancer patients. In univariate analysis of the cancer‐associated ischemic stroke and the others, there were significant differences in the prevalence of hypertension, hyperlipidemia and advanced cancer (clinical stage IV), and the levels of d ‐dimer, fibrin degradation product and hemoglobin. With multivariate regression analysis of those factors, the prevalence of hypertension, hyperlipidemia and advanced cancer (clinical stage IV), and the levels of d ‐dimer and fibrin degradation product remained as statistically independent factors, which were associated with cancer‐associated ischemic stroke (n = 111, χ2 = 67.21, P < 0.0001). Conclusion: In acute ischemic stroke, the cancer‐associated ischemic stroke is associated with elevated d ‐dimer and fibrin degradation products, even after controlling hypertension, hyperlipidemia and advanced cancer (clinical stage IV). Geriatr Gerontol Int 2012; 12: 468–474. 相似文献
50.
Masayasu Aikawa Mitsuo Miyazawa Kojun Okamoto Yasuko Toshimitsu Katsuya Okada Naoe Akimoto Yosuke Ueno Isamu Koyama Yoshito Ikada 《Surgery today》2013,43(11):1298-1304