全文获取类型
收费全文 | 214050篇 |
免费 | 3255篇 |
国内免费 | 156篇 |
专业分类
耳鼻咽喉 | 1769篇 |
儿科学 | 8388篇 |
妇产科学 | 3961篇 |
基础医学 | 21130篇 |
口腔科学 | 3511篇 |
临床医学 | 15727篇 |
内科学 | 38791篇 |
皮肤病学 | 1759篇 |
神经病学 | 19541篇 |
特种医学 | 10233篇 |
外科学 | 34808篇 |
综合类 | 2453篇 |
一般理论 | 18篇 |
预防医学 | 20531篇 |
眼科学 | 3789篇 |
药学 | 11998篇 |
中国医学 | 809篇 |
肿瘤学 | 18245篇 |
出版年
2024年 | 44篇 |
2023年 | 355篇 |
2022年 | 220篇 |
2021年 | 717篇 |
2020年 | 462篇 |
2019年 | 760篇 |
2018年 | 23070篇 |
2017年 | 18154篇 |
2016年 | 20372篇 |
2015年 | 1864篇 |
2014年 | 1874篇 |
2013年 | 2552篇 |
2012年 | 9792篇 |
2011年 | 24239篇 |
2010年 | 20159篇 |
2009年 | 12292篇 |
2008年 | 22191篇 |
2007年 | 24592篇 |
2006年 | 3502篇 |
2005年 | 5129篇 |
2004年 | 6173篇 |
2003年 | 6930篇 |
2002年 | 4911篇 |
2001年 | 1099篇 |
2000年 | 1368篇 |
1999年 | 716篇 |
1998年 | 447篇 |
1997年 | 414篇 |
1996年 | 271篇 |
1995年 | 259篇 |
1994年 | 235篇 |
1993年 | 198篇 |
1992年 | 132篇 |
1991年 | 160篇 |
1990年 | 221篇 |
1989年 | 167篇 |
1988年 | 133篇 |
1987年 | 97篇 |
1986年 | 77篇 |
1985年 | 84篇 |
1984年 | 73篇 |
1983年 | 60篇 |
1982年 | 79篇 |
1981年 | 41篇 |
1980年 | 85篇 |
1978年 | 36篇 |
1977年 | 42篇 |
1938年 | 60篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Reading abilities and cognitive functions of children with epilepsy: influence of epileptic syndrome
Chaix Y Laguitton V Lauwers-Cancès V Daquin G Cancès C Démonet JF Villeneuve N 《Brain & development》2006,28(2):122-130
Children with epilepsy are at risk of developing learning disorders. To explore the influence of the epileptic syndrome on reading abilities, we have compared the neuropsychological profile of 12 children with benign idiopathic epilepsy with rolandic spikes, 10 with temporal lobe epilepsy and 12 with idiopathic generalized epilepsy. Children underwent a selection of standardised tests designed to assess: oral language, reading, short-term memory, attention and behavioural adjustment. Analysis of variance was adjusted according to age of onset of the epileptic syndrome, duration of the syndrome, and performance IQ for each group. Children with temporal lobe epilepsy (TLE) had significantly lower scores for reading speed and comprehension, but epileptic variables (the age of onset of epilepsy, duration and activity of epilepsy) had influenced academic performances. In the TLE group there was a clear effect of the topography of the epileptic foci (left-side TLE vs. right-side TLE) on reading profile. Furthermore, the effect of epileptic syndromes was found in phonological, semantic and verbal working memory deficits in the TLE group. To a lesser extent children with idiopathic generalized epilepsy (IGE) also exhibit cognitive deficit. The results of the present study lend support to epilepsy-specific patterns of neuropsychological dysfunction in children that should be considered to improve remediation of academic underachievement in these populations. 相似文献
992.
Fèvre-Montange M Hasselblatt M Figarella-Branger D Chauveinc L Champier J Saint-Pierre G Taillandier L Coulon A Paulus W Fauchon F Jouvet A 《Journal of neuropathology and experimental neurology》2006,65(10):1004-1011
Papillary tumor of the pineal region (PTPR) is a recently described tumor entity thought to arise from the specialized ependyma of the subcommissural organ. Whereas histologic features of PTPR are well defined, data on the prognostic value of PTPR remain scarce. We therefore investigated clinicopathologic features, including data on progression-free survival and overall survival, in a retrospective series of 31 PTPR. The age of the 14 males and 17 females ranged from 5 to 66 years (median age, 29 years). Histologically, all tumors were characterized by an epithelial-like growth pattern in which the vessels were covered by layers of columnar or cuboidal tumor cells forming perivascular pseudorosettes. Most of the tumor cells showed strong expression of neuron-specific enolase, cytokeratins (particularly CK18), S-100 protein, and vimentin. Most PTPRs examined also expressed microtubule-associated protein-2. Expression of synaptophysin, epithelial membrane antigen, transthyretin, neural cell adhesion molecule, and nestin was encountered in some tumors. Gross total resection could be achieved in 21 of 31 cases; 15 patients received radiotherapy on resection of the primary tumor. Nevertheless, the majority of patients experienced recurrences; 5-year estimates for overall survival and progression-free survival were 73% and 27%, respectively. To conclude, the clinical course of PTPR is characterized by frequent local recurrence, and the value of radiotherapy on disease progression will need to be investigated in future prospective trials. 相似文献
993.
Acute-stage evolution of watershed infarction assessed on diffusion-weighted MR imaging 总被引:2,自引:0,他引:2
Kim SJ Lee CW Kim HJ Lee JH Lee DH Choi CG Suh DC Kang DW 《Cerebrovascular diseases (Basel, Switzerland)》2006,21(5-6):357-362
BACKGROUND: To investigate acute stage (<5 days) evolution of the watershed infarction (WI) on diffusion-weighted (DW) magnetic resonance (MR) imaging and to evaluate the role of perfusion MR imaging in predicting the progression of watershed infarction. METHODS: Twenty-eight patients with acute WI within 24 h after symptom onset were selected for this study. Criterion for WI was based on DW images. We assessed the infarct volume changes between the initial and follow-up (mean: 2.2 days) DW images. Perfusion images were obtained in 20 patients at the initial work-up and sensitivity, specificity, and accuracy of perfusion-diffusion mismatch in predicting severe infarct progression were evaluated. Clinical outcome was assessed by using National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). RESULTS: Infarct volumes on initial and follow-up DW images were 8.6+/-7.7 cm3 and 20.2+/-27.0 cm3, respectively. Twenty-one cases showed no or slight increment (<15 cm3) of infarct volume on follow-up MR imaging and seven cases showed severe progression (>15 cm3 increment). Among 20 cases in which perfusion maps were obtained, 5 cases showed perfusion-diffusion mismatch: among those, 4 developed severe progression of infarction. Severe progression group showed higher follow-up NIHSS score and poor outcome by 90-day mRS score. CONCLUSION: WI usually begins as a small volume lesion, and progression of infarction during the acute stage is usually limited in most cases. Perfusion imaging may have an important role in predicting severe infarct progression in WI. 相似文献
994.
OBJECTIVES: The aims of the study were (i) to examine the localizing value of three MRI quantitative modalities (qMRI) currently used for the analysis of the hippocampus and amygdala in the context of pre-surgical screening and (ii) to propose a step-by-step protocol based on the sensitivity and performance of the different MR techniques. METHODS: Ninety-two adults with chronic mesial temporal lobe epilepsy (TLE) of which 28 underwent amygdalo-hippocampal resection, and 34 age-matched controls were included in the study. High-resolution qMRI was performed at 1.5 T, including a tilted T1-weighted 3D-dataset for volumetry and four-echoes T2 relaxometry (both for hippocampus and amygdala quantifications) and multi-voxel spectroscopy [NAA/(Cho+Cre)] (exclusively in the hippocampus). Individual qMRI data were compared with electroencephalography regarding the localization of the epileptogenic area, with the neuropathological data and with postoperative outcome. MRI pathology was defined based on 99% confidence ellipses. Ten controls were used to assess the quantitative MRI intra- and inter-observer variability for all variables. RESULTS: Volumetric measurements revealed unilateral damage in 77% of the patients, T2-relaxometry in 64% and spectroscopy in 53%. Additional measurements of the amygdalae (T2-relaxometry) allowed us to localize pathology that coexists with that of the hippocampus in 34%, and isolated unilateral amygdala damage in 8% of patients. Volumetry and T2-relaxometry (not spectroscopy) were associated with postoperative outcome, but accurate predictive models were computed based on hippocampal measures only. At least at 1-year follow-up, volumetry predicts outcome correctly in 100% of the cases, whilst T2-relaxometry classified 96.4% (27/28) of these patients. All operated patients had hippocampal sclerosis. CONCLUSIONS: Hippocampal structural damage is equivocally depicted by spectroscopy. For diagnostic and pre-operative evaluation, hippocampal volumetry and T2-relaxometry provide maximal accuracy. Amygdala quantifications are irrelevant in the pre-operative evaluation but may be useful for diagnostic purposes. Of the three qMRI modalities tested, T2-relaxometry provided the best balance between diagnosis accuracy and time-efficiency to lateralize a sclerotic lesion on the majority of the patients. Cases that remain undecided after T2-relaxometry may benefit from additional measurements based on hippocampal volumetry. 相似文献
995.
Camdessanché JP Lassablière F Meyronnet D Férraud K Absi L Honnorat J Antoine JC 《Journal of neuroimmunology》2006,174(1-2):168-173
Anti-CV2 antibodies (AB) react with the developmentally regulated neural proteins CRMPs and particularly with CRMP5. They occur with small cell lung cancer (SCLC) and thymoma. SCLCs universally express CRMP5. We investigated the expression of CRMPs in thymoma and thymus. In thymoma, none of the CRMPs were detected by immunohistochemistry in tumorous epithelial cells with specific antibodies including CRMP5 but an antibody reacting with a peptide common to the CRMPs labeled a 66-kDa protein in Western blot of rat brain, thymus, and thymoma extracts. Thus, the normal CRMP5 is probably not expressed by tumorous epithelial cells. These results indicate that the mechanisms leading to CRMP5 autoimmunization are different in SCLC and thymoma. 相似文献
996.
Effect of fetal neural transplants in patients with Huntington's disease 6 years after surgery: a long-term follow-up study 总被引:2,自引:0,他引:2
Bachoud-Lévi AC Gaura V Brugières P Lefaucheur JP Boissé MF Maison P Baudic S Ribeiro MJ Bourdet C Remy P Cesaro P Hantraye P Peschanski M 《Lancet neurology》2006,5(4):303-309
BACKGROUND: Although we have shown in three out of five patients with Huntington's disease that motor and cognitive improvements 2 years after intracerebral fetal neural grafts are correlated with recovery of brain metabolic activity in grafted striatal areas and connected regions of the cerebral cortex, neural grafts are not known to have protective effects on the host brain per se. We undertook long-term follow-up of previously reported patients with the disease to ascertain the nature and extent of any secondary decline after grafting. METHODS: Five patients with Huntington's disease from our pilot study were assessed annually with the unified Huntington's disease rating scale, neuropsychological tests, and MRI, for up to 6 years after neural grafting. Resting cerebral activity was recorded at 2 and 6 years. FINDINGS: Clinical improvement plateaued after 2 years and then faded off variably 4-6 years after surgery. Dystonia deteriorated consistently, whereas chorea did not. Cognitive performance remained stable on non-timed tests, whereas progression of motor disability was shown by deterioration on timed tests. Hypometabolism also affected the brain heterogeneously, sparing the benefits in the frontal cortex and at the precise location of the grafts, but showing a progressive deterioration in other areas. Two patients who had no benefit from grafting at 2 years continued to decline in the same way as non-grafted patients. INTERPRETATION: Neuronal transplantation in Huntington's disease provides a period of several years of improvement and stability, but not a permanent cure for the disease. Improvement of the surgical procedure and in patient selection could improve the therapeutic value, but neuroprotective treatment seems to be unavoidable in the disease. 相似文献
997.
Wang MY 《Acta neurochirurgica》2011,153(3):557-557
998.
Iris Zachenhofer Klaus Novak Christoph Baumgartner Daniela Prayer Thomas Czech 《Acta neurochirurgica》2011,153(2):239-248
Background
Selective amygdalohippocampectomy (SAHE) yields 60–80% of patients with medically refractory mesial temporal lobe epilepsy seizure-free and seems to be equally effective compared to the more extended temporal lobe resections. The resection of the entire entorhinal cortex (EC) is of crucial importance to warrant complete seizure control for those patients. Thus, evidence of residual EC could be a predictor of a potentially successful reoperation in patients with recurrent seizures after SAHE. We performed an analysis of preoperative and postoperative magnetic resonance imaging (MRI) in patients who underwent a reoperation after an unsuccessful transsylvian SAHE to assess the presence of residual EC before reoperation and to determine whether certain anatomical variants may dispose patients to incomplete resection of EC. 相似文献999.
1000.
Application of the Ilizarov Technique to the Correction of Neurologic Equinocavovarus Foot Deformity
Dong Yeon Lee In Ho Choi Won Joon Yoo Soong Joon Lee Tae-Joon Cho 《Clinical orthopaedics and related research》2011,469(3):860-867