全文获取类型
收费全文 | 927篇 |
免费 | 57篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 46篇 |
妇产科学 | 59篇 |
基础医学 | 82篇 |
口腔科学 | 113篇 |
临床医学 | 82篇 |
内科学 | 184篇 |
皮肤病学 | 17篇 |
神经病学 | 113篇 |
特种医学 | 29篇 |
外科学 | 109篇 |
综合类 | 5篇 |
预防医学 | 36篇 |
眼科学 | 34篇 |
药学 | 38篇 |
中国医学 | 1篇 |
肿瘤学 | 26篇 |
出版年
2024年 | 1篇 |
2023年 | 15篇 |
2022年 | 26篇 |
2021年 | 61篇 |
2020年 | 39篇 |
2019年 | 42篇 |
2018年 | 52篇 |
2017年 | 44篇 |
2016年 | 52篇 |
2015年 | 49篇 |
2014年 | 65篇 |
2013年 | 68篇 |
2012年 | 108篇 |
2011年 | 75篇 |
2010年 | 26篇 |
2009年 | 35篇 |
2008年 | 49篇 |
2007年 | 38篇 |
2006年 | 54篇 |
2005年 | 35篇 |
2004年 | 24篇 |
2003年 | 13篇 |
2002年 | 11篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 1篇 |
排序方式: 共有987条查询结果,搜索用时 15 毫秒
981.
Hikmet Can Çubukçu Mustafa Yurtdaş Zahide Esra Durak Bilal Aytaç Hafize Nalan Güneş Burcu Gökçe Çokal Tahir Kurtuluş Yoldaş İlker Durak 《Neurological sciences》2016,37(11):1793-1798
Parkinson’s disease (PD) is one of the common neurodegenerative disorders. Oxidative stress is considered as a contributing factor to the development of PD. The present study aims to investigate serum oxidative stress status in patients with PD. Oxidative stress was assessed by measuring serum nitric oxide levels, lipid hydroperoxide concentrations, and nitric oxide synthase activity. In addition, total serum antioxidant capacity (TAC) was evaluated using the serum 2,2-Diphenyl-1-picryl-hydrazyl (DPPH) free-radical scavenging method in 32 patient with Parkinson’s disease and 32 control subjects. Our results indicated that serum nitric oxide and lipid hydroperoxide levels were significantly lower in patients with PD than controls. Moreover, nitric oxide levels were found to be negatively correlated with Unified Parkinson’s Disease Rating Scale (UPDRS). However, no statistical difference was observed in total serum antioxidant capacities and nitric oxide synthase activities between patients and controls. The present study indicates that although antioxidant capacity was not changed, lipid hydroperoxide (LPO) level was found decreased. This might show pre-oxidative process in these patients. In addition, decreased nitric oxide (NO) level and negative correlation observed between NO level and disease rating scale implicated a role for NO in the disease process. 相似文献
982.
Burcu Erdogan Garrett M. Cammarata Eric J. Lee Benjamin C. Pratt Andrew F. Francl Erin L. Rutherford Laura Anne Lowery 《Neural development》2017,12(1):3
Background
Formation of precise neuronal connections requires proper axon guidance. Microtubules (MTs) of the growth cone provide a critical driving force during navigation of the growing ends of axons. Pioneer MTs and their plus-end tracking proteins (+TIPs) are thought to play integrative roles during this navigation. TACC3 is a?+?TIP that we have previously implicated in regulating MT dynamics within axons. However, the role of TACC3 in axon guidance has not been previously explored.Results
Here, we show that TACC3 is required to promote persistent axon outgrowth and prevent spontaneous axon retractions in embryonic Xenopus laevis neurons. We also show that overexpressing TACC3 can counteract the depolymerizing effect of low doses of nocodazole, and that TACC3 interacts with MT polymerase XMAP215 to promote axon outgrowth. Moreover, we demonstrate that manipulation of TACC3 levels interferes with the growth cone response to the axon guidance cue Slit2 ex vivo, and that ablation of TACC3 causes pathfinding defects in axons of developing spinal neurons in vivo.Conclusion
Together, our results suggest that by mediating MT dynamics, the?+?TIP TACC3 is involved in axon outgrowth and pathfinding decisions of neurons during embryonic development.983.
Nesrin Cevik Ayhan Koksal Vasfiye Burcu Dogan Ayten Ceyhan Dirican Sibel Bayramoglu Musa Ozturk Sevim Baybas 《Neurological sciences》2016,37(4):623-627
Our aim in this research is investigating the hypothesis of biochemical changes in frontal cortex and thalamocortical pathways in juvenile myoclonic epilepsy (JME) and the interaction between the biochemical changes and cortical functions. Magnetic resonance spectroscopy (MRS) was applied to 20 JME patients and 20 controls for measuring N-acetyl aspartate (NAA), N-acetyl aspartate to creatine ratio (NAA/Cr), Glutamine and Glutamate (GLX), Glutamine–Glutamate to creatine (GLX/Cr), Choline containing compounds (Cho) and Choline to creatine (Cho/Cr) levels. Neuropsychological cognitive tests for linguistic and visual attention, linguistic and visual memory, visuospatial and executive functions were applied to all participants. NAA and NAA/Cr concentrations were found lower in bilateral frontal and thalamic regions in JME group as compared with the control group (p < 0.05). There was no difference in frontal and thalamic GLX, GLX/Cr, Cho, Cho/Cr levels in between JME patients and controls (p > 0.05). JME patients were found more unsuccessful than the controls in attention, memory, visuospatial function, verbal fluency, Trail B test and executive functions, stroop test, clock drawing test and Trail A test (p < 0.05). Prefrontal NAA/Cr level was positively related to visual attention, memory, stroop test and thalamic NAA/Cr level was positively related to linguistic memory and Wisconsin card sorting test in JME patients. This research highlights regional brain changes and cognitive decline in JME patients and suggests that MRS may be a sensitive technique for showing subclinical cognitive changes. 相似文献
984.
Bas B Ozden B Bekcioglu B Sanal K Yilmaz S Celik B Basoglu A Celenk C 《Oral surgery, oral medicine, oral pathology and oral radiology》2012,114(3):e15-e18
Descending necrotizing mediastinitis (DNM) is a rare condition in which an infection from the head and neck propagates into the mediastinum. The most common cause of DNM is odontogenic infection. DNM is spread by the fascial planes from the neck into the mediastinum and requires an aggressive surgical drainage through cervical and thoracic approaches. We report on a 67-year-old male patient, who had acute mediastinitis related to an infected dentigerous cyst in the left parasymphyseal region. A multidisciplinary team approach was used to treat the patient. The team consisted of thoracic surgeons, maxillofacial surgeons, and a radiologist. After the drainage of the mediastinum and pleural cavity, the cyst was enucleated. The patient was discharged at the 42nd day of hospitalization. The aim of this article is to present diagnosis, management, and follow-up of an infected dentigerous cyst that caused DNM. 相似文献
985.
ObjectiveThe aim of this study was to evaluate the effect of systemic thymoquinone (TQ) in a rat rapid maxillary expansion (RME) study.DesignThirty-two Wistar albino rats were divided into 4 equal groups: only-expansion (OE), expansion plus TQ (TQ1 group, TQ given to the rats during their nursery phase and during the expansion and retention period), expansion plus TQ (TQ2 group, TQ given to the rats only during the retention period), and control group (no procedure done). Expansion appliances were placed on the maxillary incisors of all animals for 5 days. The appliance was deactivated during the 12 day retention period. The rats were sacrificed at the end of the retention period. Histomorphometric evaluation was carried out in order to compare the number of osteoclasts, osteoblasts, and capillaries, as well as the intensities of inflammatory cells, and new bone formation amongst the groups.ResultsNew bone formation, number of capillaries and the ratio of intensities of inflammatory cells in maxillary sutures was higher in the TQ groups than in the other groups. Statistical analysis also demonstrated that osteoblast and osteoclast numbers were also highest in the TQ1 group.ConclusionHistomorphometric analysis demonstrated that systemic use of thymoquinone may be effective in accelerating new bone formation in the RME procedure and that TQ may be beneficial in preventing relapse following the RME procedure. 相似文献
986.
Yasemin Akgun Aysun Soysal Dilek Atakli Burcu Yuksel Cengiz Dayan Baki Arpaci 《Seizure》2009,18(6):387-391
In this study, we aimed to evaluate motor cortical excitability changes in patients with juvenile myoclonic epilepsy (JME) and their asymptomatic siblings (AS) using single-pulse transcranial magnetic stimulation (spTMS). 21 patients with JME and their 21 AS were compared to 20 healthy controls. All of JME patients were receiving antiepileptic therapy and their seizures were well controlled. Firstly, standard EEG examinations and then TMS studies were performed. Resting motor threshold (RMT), motor evoked potential (MEP) amplitudes, the durations of central motor conduction time (CMCT) and cortical silent period (CSP) were measured. After TMS studies, EEG recordings were repeated in an hour to evaluate any effect of TMS study on EEG. There were no significant differences between the first and second EEG recordings. No seizures were recorded during and after the TMS study. RMT was found higher in JME patients than AS and normal controls. There were no significant differences between cortical MEP amplitudes and MEP amplitude/CMAP (compound muscle action potential) amplitude ratio in all three groups. CMCT duration was shorter in JME patients than AS. CSP durations of JME patients were found to be longer than controls. In AS, CSP durations were also found to be longer than controls but this difference was not found statistically significant. Our results suggested that although high MT may be related to antiepileptic therapy, the prolongation of CSP duration may reflect impairment of supraspinal and/or intracortical inhibitory mechanism in JME. To eliminate the drug effect, further studies are needed in newly diagnosed JME patients without medication and large series of their asymptomatic siblings. 相似文献
987.
Emrah Alt?ndi? Burcu E. Tefon Volkan Y?ld?r?m Erkan Özcengiz Dörte Becher Michael Hecker Gülay Özcengiz 《Vaccine》2009
Bordetella pertussis is the causative agent of highly communicable respiratory infection whooping cough (pertussis) which remains one of the world's leading causes of vaccine-preventable deaths. In the present study, total soluble proteins extracted from two B. pertussis strains, Tohama I and the local isolate Saadet were separated by two-dimensional gel electrophoresis and analyzed by Western blotting for their reactivity with the antisera obtained from the mice immunized with inactivated whole cells as well as those collected from the mice challenged intraperitoneally with live cells of each strain. Of a total of 25 immunogenic proteins identified, 21 were shown to be the novel antigens for B. pertussis. 相似文献