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The flash-lag effect (FLE) is the perceptual phenomenon in which a flash adjacent to a continuously moving object is perceived behind it. Horizontal propagation of activity could explain a shorter latency for moving than for flashed objects but, to our knowledge, no psychophysical data supporting this has been given. We show that two concurrent moving stimuli increase the FLE, presumably due to a latency decrease in movement perception. Our results support the idea that spatial facilitation along the trajectory of a moving object reduces movement perception delay and, therefore, sustains an involvement of latency differences in FLE generation.  相似文献   
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BACKGROUND: Mycetoma is a chronic infection caused by aerobic actinomycetes and filamentous fungi. It is an occupational disease frequent in tropical countries and is uncommon in children. METHODS: A retrospective (25 years) report of mycetomas was conducted in children less than 15 years of age. Each of the cases was studied clinically and proven with microbiologic tests: direct examinations (to identify and classify the grains), cultures and identification based on morphology and biochemical tests. The therapeutic experience of the cases was also reviewed. RESULTS: In a 25-year period, a total of 334 mycetomas were seen at our institution, 15 of which (4.5%) were in patients 15 years of age and younger (mean age: 11.2 years, age range: 6-15 years). Twelve cases were males and 3 females. The main clinical location was the foot in 10 of 15 (66.6%). Etiologies included 13 actinomycetomas and 2 eumycetomas. Etiologic agents were Nocardia brasiliensis in 12 cases, Nocardia asteroides in one and Madurella mycetomatis in 2. Eleven of the13 cases of actinomycetomas treated with trimethoprim-sulfamethoxazole plus diaminodiphenylsulfone were cured. The 2 failures were successfully treated with amoxicillin/clavulanate. One of the eumycetomas was cured with itraconazole therapy, whereas the other failed various treatments eventuating in surgical amputation. CONCLUSIONS: Mycetomas are exceptional in children; in our setting, actinomycetomas are more frequent than eumycetomas. The clinical and microbiologic diagnosis is simple. Overall, treatment response is better for actinomycetomas than for eumycetomas.  相似文献   
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IntroductionInsula plays an integrating role in sensory, affective, emotional, cognitive and autonomic functions in migraine, especially in migraine with aura (MA). Insula is functionally divided into 3 subregions, the dorsoanterior, the ventroanterior and the posterior insula respectively related to cognition, emotion, and somatosensory functions. This study aimed at investigating functional connectivity of insula subregions in MA.MethodsTwenty-one interictal patients with MA were compared to 18 healthy controls (HC) and 12 interictal patients with migraine without aura (MO) and were scanned with functional MRI during the resting state. Functional coupling of the insula was comprehensively tested with 12 seeds located in the right and left, dorsal, middle, ventral, anterior and posterior insula, by using a seed-to-voxel analysis.ResultsSeed-to-voxel analysis revealed, in MA, a strong functional coupling of the right and left antero-dorsal insula with clusters located in the upper cerebellum. The overlap of these cerebellar clusters corresponded to the vermis VI. These functional couplings were not correlated to duration of MA, frequency of MA attacks nor time since last MA attack, and were not found in MO.DiscussionThe anterior insula and superior cerebellum, including vermis VI, are components of the central Autonomic Nervous System (ANS) network. As these regions are involved in the control of cardiovascular parasympathetic tone, we hypothesize that this connectivity may reflect the cardiovascular features of MA.ConclusionThe anterior dorsal insula is connected with vermis VI in MA patients in the resting state. This connectivity may reflect the cardiovascular features of MA.Trial registrationNCT02708797.  相似文献   
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Gastric emptying, gastric secretion and esophageal pH were studied prospectively in 32 patients who had either a Lortat-Jacob type operation (n = 7) or a fundoplication with a 360 degrees (n = 4), 270 degrees (n = 5) or 180 degrees (n = 16) gastric fundic wrap. The goal was to determine the effects of various antireflux mechanisms on these functions as well as to try to explain abnormal postoperative esophageal pH scoring indexes. Esophageal pH was recorded during the 3 h period following a standard meal. Acid reflux was expressed using a scoring index taking into account the duration and magnitude of pH fall. Preoperatively, all patients had an abnormal pH scoring index. Postoperatively, the pH scoring index remained increased in 7 patients (group A) and returned to normal values in 25 (group B). Clinical data, esophageal pH parameters and gastric acid secretion measured preoperatively were not significantly different in the two groups of patients. Preoperative gastric emptying for liquids was shorter in group A than in group B patients (p less than 0.05). Postoperative gastric emptying of radiopaque markers was not different in the two groups of patients. Postoperative resting pressure of the lower esophageal sphincter was always less than 10 cm H2O in group A and more than 10 cm H2O in group B patients. Changes in lower esophageal pressure after surgery were higher in group B than in group A patients (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A 17 year-old girl with chronic idiopathic intestinal pseudo-obstruction is reported. Abnormalities of smooth intestinal muscle were shown on light and electron microscopic studies of the excised small intestine and led to the diagnosis of visceral myopathy based on the following features: vacuolar degeneration of intestinal smooth muscle cells with replacement by fibrous preferential involvement of the external longitudinal muscle layer normal myenteric plexus. For the first time similar ultrastructural changes were found on histological study of the colon. Manometric studies revealed a diffuse disease involving the esophagus, small bowel, and bladder. Anorectal abnormalities, never described before, were reported. Family involvement was shown by abnormal esophageal and anorectal manometries in the patient's brother and by paternal history of fatal small intestine occlusion without mechanical obstruction. The prognosis of severe forms of visceral myopathy is generally poor because of the inefficiency of drugs. In this case, after a long period of parenteral nutrition with maintenance of a good nutritional status, a terminal ileostomy (with a special procedure to avoid evagination) associated with a second stage total colectomy allowed to stop parenteral nutrition.  相似文献   
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Background: To identify new epigenetic markers and further characterize Urothelial Cell Carcinoma (UCC), we tested the promoter methylation (PM) status of 19 genes previously identified as cancer specific methylated genes in other solid tumors.Methods: We used bisulfite sequencing, methylation specific PCR and quantitative methylation specific PCR (QMSP) to test the PM status of 19 genes in urothelial cancer cell lines.Results: Among the 19 genes tested, VGF was found to be completely methylated in several UCC cell lines. VGF QMSP analysis showed that methylation values of almost all the primary 19 UCC tissues were higher than the paired normal tissues (P=0.009). In another cohort, 12/35 (34.3%) of low grade UCC cases displayed VGF methylation. As a biomarker for non-invasive detection of UCC, VGF showed a significantly higher frequency of methylation in urine from UCC cases (8/20) compared to controls (1/20) (P=0.020). After treatment of cell lines with 5-Aza-2''-deoxycytidine, VGF was robustly re-expressed. Forced expression of VGF in bladder cancer cell lines inhibited cell growth.Conclusion: Selection of candidates from genome-wide screening approach in other solid tumors successfully identified UCC specific methylated genes.  相似文献   
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