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Clinical manifestations of human papillomavirus (HPV) infection in the head and neck can range from benign lesions, which are the most frequent, to malignant lesions. The prevalence of head and neck cancer is increasing, despite currently decreasing trends in known risk factors such as smoking and alcohol use. A new patient profile has appeared in recent practice: most frequently a middle‐aged male patient who does not smoke or drink alcohol, is sexually active (possibly having multiple partners), and presents with oral or cervicofacial lesions requiring diagnosis and treatment. Another risk factor that should be considered in these patients is HPV infection. The association of oral potentially malignant disorders (OPMD) with HPV is a challenge for the medical practitioner. The gold standard for diagnosis is histopathological examination, which can also yield evidence suggesting HPV infection. Determination of the viral genotype provides additional data for assessing the oncological risk of an HPV infection. Treatment of these patients is aimed at removing the lesions, in association or not with antiviral treatment and recurrence control. Clin. Anat. 28:1002–1007, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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Background

Cerebral vasculopathy is a serious complication of sickle cell anemia. Overt strokes are largely due to intracranial arteriopathy, detected by routine transcranial Doppler and largely prevented through chronic transfusions. As extracranial internal carotid artery arteriopathy was considered rare, it has not been routinely assessed in sickle cell anemia. Recent cases of overt strokes associated with stenosis/occlusion of the extracranial portion of the internal carotid artery prompted us to include extracranial internal carotid artery assessment to our transcranial Doppler sonography protocol.

Objective

The aim of the study was to perform a cross-sectional study in children with sickle cell anemia to evaluate Doppler flow patterns of the extracranial internal carotid arteries and to assess potential associated factors.

Materials and methods

Between June 2011 and April 2012, 435 consecutive stroke-free children with sickle cell anemia (200/235 M/F, median age: 7.9 years) were assessed for extracranial internal carotid artery using a 2-MHz transcranial Doppler sonography probe via a submandibular window during routine transcranial Doppler sonography visits. The course of both extracranial internal carotid artery was assessed by color Doppler mapping, and the highest flow velocity was recorded after insonation of the entire length of the artery and analyzed. Intra- and extracranial MR angiographies were available in 104/435 subjects for comparison.

Results

Mean (SD) extracranial internal carotid artery time-averaged mean of maximum velocity was 96 (40) cm/s. Extracranial internal carotid artery tortuosities were echo-detected in 25% cases and were more frequent in boys (33% vs.18%; P?<?0.001). Velocity ≥160 cm/s in at least one extracranial internal carotid artery was found in 45 out of 435 patients with sickle cell anemia (10.3%) and was highly predictive of MR angiography stenosis. Simultaneous abnormal intracranial velocity (≥200 cm/s) was recorded in 5/45 patients, while 40 patients had isolated extracranial internal carotid artery velocity ≥160 cm/s. Low hemoglobin (odds ratio: 1.9/g/dL, 95% confidence interval (CI): 1.3–2.9; P?=?0.001) and tortuosities (odds ratio: 19.2, 95% CI: 7.1–52.6; P?<?0.001) were significant and independent associated factors for isolated extracranial internal carotid artery velocities ≥160 cm/s.

Conclusion

Adding extracranial internal carotid artery evaluation via the submandibular window to transcranial Doppler sonograpy allowed us to detect 10.3% patients at risk for extracranial internal carotid arteriopathy. Further studies are needed to evaluate the prognosis of these anomalies.  相似文献   
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The congenitally missing maxillary lateral incisor is the most common agenesis in the anterior region. There are several treatment options for this anomaly, which causes severe deficiencies: orthodontic space closure, tooth‐supported restoration, or single‐tooth implant. Each of these solutions has a high degree of success if used in the correct situation. An implant‐supported restoration with an interdisciplinary approach provides a predictable outcome. This article describes the treatment of a patient with agenesis of the maxillary left lateral incisor. After orthodontic space management, it was decided to restore the tooth with an all‐ceramic crown cemented on a zirconia custom abutment, which fractured after only 6 weeks of service. Fractographic analysis revealed that the failure was due to over‐reduction of the buccal wall to correct the labial emergence of the implant. Zirconia abutments should be designed with even wall thicknesses of at least 0.8 mm to avoid areas that may compromise functional success.  相似文献   
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Duchenne muscular dystrophy (DMD) is an X‐linked myopathy caused by dystrophin deficiency. Dystrophin is present intracellularly at the sarcolemma, connecting actin to the dystrophin‐associated glycoprotein complex. Interestingly, it is enriched postsynaptically at the neuromuscular junction (NMJ), but its synaptic function is largely unknown. Utrophin, a dystrophin homologue, is also concentrated at the NMJ, and upregulated in DMD. It is possible that the absence of dystrophin at NMJs in DMD causes neuromuscular transmission defects that aggravate muscle weakness. We studied NMJ function in mdx mice (lacking dystrophin) and wild type mice. In addition, mdx/utrn+/? and mdx/utrn?/? mice (lacking utrophin) were used to investigate influences of utrophin levels. The three Duchenne mouse models showed muscle weakness when comparatively tested in vivo, with mdx/utrn?/? mice being weakest. Ex vivo muscle contraction and electrophysiological studies showed a reduced safety factor of neuromuscular transmission in all models. NMJs had ~ 40% smaller miniature endplate potential amplitudes compared with wild type, indicating postsynaptic sensitivity loss for the neurotransmitter acetylcholine. However, nerve stimulation‐evoked endplate potential amplitudes were unchanged. Consequently, quantal content (i.e. the number of acetylcholine quanta released per nerve impulse) was considerably increased. Such a homeostatic compensatory increase in neurotransmitter release is also found at NMJs in myasthenia gravis, where autoantibodies reduce acetylcholine receptors. However, high‐rate nerve stimulation induced exaggerated endplate potential rundown. Study of NMJ morphology showed that fragmentation of acetylcholine receptor clusters occurred in all models, being most severe in mdx/utrn?/? mice. Overall, we showed mild ‘myasthenia‐like’ neuromuscular synaptic dysfunction in several Duchenne mouse models, which possibly affects muscle weakness and degeneration.  相似文献   
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Bulletin of Environmental Contamination and Toxicology - Although water pollution by metals in the Danube River is considered high, little is known about its impact on sturgeons. In this regard,...  相似文献   
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Introduction and objectivesInadequate auditory feedback in prelingually deaf children alters the articulation of consonants and vowels.The purpose of this investigation was to compare vowel production in Spanish-speaking deaf children with cochlear implantation, and with hearing-aids with normal-hearing children by means of acoustic analysis of formant frequencies and vowel space.MethodsA total of 56 prelingually deaf children (25 with cochlear implants and 31 wearing hearing-aids) and 47 normal-hearing children participated. The first 2 formants (F1 and F2) of the five Spanish vowels were measured using Praat software. One-way analysis of variance (ANOVA) and post hoc Scheffé test were applied to analyze the differences between the 3 groups. The surface area of the vowel space was also calculated.ResultsThe mean value of F1 in all vowels was not significantly different between the 3 groups. For vowels /i/, /o/ and /u/, the mean value of F2 was significantly different between the 2 groups of deaf children and their normal-hearing peers.ConclusionBoth prelingually hearing-impaired groups tended toward subtle deviations in the articulation of vowels that could be analyzed using an objective acoustic analysis programme.  相似文献   
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