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排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. Forty percent of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyxoid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion. 相似文献
2.
The Jansen type of metaphyseal dysplasia is a rare disorder with significant clinical and radiographic variability. Two cases of classical Jansen disease and one with some distinctive features suggestive of the Jansen variant are reported. 相似文献
3.
Dynamic spike threshold reveals a mechanism for synaptic coincidence detection in cortical neurons in vivo 下载免费PDF全文
Azouz R Gray CM 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(14):8110-8115
Cortical neurons are sensitive to the timing of their synaptic inputs. They can synchronize their firing on a millisecond time scale and follow rapid stimulus fluctuations with high temporal precision. These findings suggest that cortical neurons have an enhanced sensitivity to synchronous synaptic inputs that lead to rapid rates of depolarization. The voltage-gated currents underlying action potential generation may provide one mechanism to amplify rapid depolarizations. We have tested this hypothesis by analyzing the relations between membrane potential fluctuations and spike threshold in cat visual cortical neurons recorded intracellularly in vivo. We find that visual stimuli evoke broad variations in spike threshold that are caused in large part by an inverse relation between spike threshold and the rate of membrane depolarization preceding a spike. We also find that spike threshold is inversely related to the rate of rise of the action potential upstroke, suggesting that increases in spike threshold result from a decrease in the availability of Na(+) channels. By using a simple neuronal model, we show that voltage-gated Na(+) and K(+) conductances endow cortical neurons with an enhanced sensitivity to rapid depolarizations that arise from synchronous excitatory synaptic inputs. Thus, the basic mechanism responsible for action potential generation also enhances the sensitivity of cortical neurons to coincident synaptic inputs. 相似文献
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Shwikar AbdelSalam Ahmed Azza Mahmoud Elhefnawy Hanan Galal Azouz Yara Safwat Roshdy Mona Hamdy Ashry Ahmed Elsayed Ibrahim Marwa Ahmed Meheissen 《Journal of molecular neuroscience : MN》2020,70(6):887-896
The role of gut microbiome was recently raised in the pathogenesis of neurodevelopmental disorders including autism spectrum disorder (ASD). The aim of this study was to elucidate changes in gut microbiome in Egyptian autistic children and its possible correlation with the severity of autism and gastrointestinal (GI) symptoms. The gut bacterial microbiome of 41 ASD children, 45 siblings, and 45 healthy controls were analyzed using quantitative SYBR Green real-time PCR technique targeting 16S rRNA of selected bacteria. The gut microbiome of ASD children and their siblings contained a higher relative abundance of Bacteroides as well as Ruminococcus than controls. Prevotella/Bacteroides (P/B) ratio and Firmicutes/Bacteroidetes (F/B) were significantly lower in both ASD cases and their siblings. The only difference between the autistic cases and their siblings was the significantly higher level of Bifidobacterium in siblings, which appears to offer them a protective role. There was no correlation between the altered gut microbiome and the severity of autism or GI symptoms. The current study showed an evidence of changes in the gut microbiome of autistic children compared to the unrelated control. However, the microbiome profile of siblings was more like that of autistic children than that of unrelated controls indicating that gut microbiota is affected by dietary habits, living conditions together with host genetic factors. 相似文献
6.
Anissa Chouikha Wasfi Fares Asma Laamari Sondes Haddad-Boubaker Zeineb Belaiba Kais Ghedira Wafa Kammoun Rebai Kaouther Ayouni Marwa Khedhiri Samar Ben Halima Henda Krichen Henda Touzi Imen Ben Dhifallah Fatma Z. Guerfali Chiraz Atri Saifeddine Azouz Oussema Khamessi Monia Ardhaoui Mouna Safer Nissaf Ben Alaya Ikram Guizani Rym Kefi Mariem Gdoura Henda Triki 《Viruses》2022,14(3)
Documenting the circulation dynamics of SARS-CoV-2 variants in different regions of the world is crucial for monitoring virus transmission worldwide and contributing to global efforts towards combating the pandemic. Tunisia has experienced several waves of COVID-19 with a significant number of infections and deaths. The present study provides genetic information on the different lineages of SARS-CoV-2 that circulated in Tunisia over 17 months. Lineages were assigned for 1359 samples using whole-genome sequencing, partial S gene sequencing and variant-specific real-time RT-PCR tests. Forty-eight different lineages of SARS-CoV-2 were identified, including variants of concern (VOCs), variants of interest (VOIs) and variants under monitoring (VUMs), particularly Alpha, Beta, Delta, A.27, Zeta and Eta. The first wave, limited to imported and import-related cases, was characterized by a small number of positive samples and lineages. During the second wave, a large number of lineages were detected; the third wave was marked by the predominance of the Alpha VOC, and the fourth wave was characterized by the predominance of the Delta VOC. This study adds new genomic data to the global context of COVID-19, particularly from the North African region, and highlights the importance of the timely molecular characterization of circulating strains. 相似文献
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Scuccimarri R Azouz EM Duffy KN Fassier F Duffy CM 《Annals of the rheumatic diseases》2000,59(11):864-869
Osteochondrodysplasias are a heterogeneous group of genetic skeletal dysplasias. Patients with these diseases commonly develop an early degenerative arthritis or osteoarthritis. Occasional observations of inflammatory arthritis have been made in this population but such observations are based on clinical grounds alone without confirmatory imaging studies. Four patients followed up in a paediatric rheumatology clinic with three different skeletal dysplasias, who had both clinical and radiological evidence of an inflammatory arthritis and coexistent degenerative arthritis, are described. 相似文献
9.
Antro-choanal polyp: a 10-year retrospective study in the pediatric population with a review of the literature 总被引:1,自引:0,他引:1
Antro-choanal polyp is generally recognized to represent approximately 4-6% of all nasal polyps; however, it is much more prevalent in the pediatric population. It warrants special consideration in children because its clinical manifestations may be mimicked by other less benign conditions, such as juvenile angiofibroma, meningoencephalocele, and nasopharyngeal malignancies. Fifty patients with surgically treated nasal polyps were reviewed at the Montreal Children's Hospital, between 1976 and 1986. Fourteen (28%) were antro-choanal polyps. Our results are compared with the literature, and special emphasis was given to radiographic manifestations and the differential diagnoses. 相似文献
10.
An adolescent with classical Williams' syndrome who presented with hypertensive encephalopathy is described. He had the unusual combination of supravalvular aortic stenosis, long segment coarctation of the aorta, aortic hypoplasia and a high bifurcation of the abdominal aorta. Surgical resection of the coarctation was required; however, the patient has remained moderately hypertensive. The aortic anomalies in this syndrome are reviewed and their frequency and importance examined. 相似文献