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《Neuro-Chirurgie》2021,67(6):579-586
BackgroundLiponeurocytoma is an uncommon tumor of the central nervous system. It is very rare for this tumor to originate within the lateral ventricle. In the context of the rarity of this tumor entity, this review article aims to summarize the clinical, radiological, and pathological features of lateral ventricular liponeurocytoma to facilitate its diagnosis and management.MethodsHere, we conduct a systematic literature review using the Pubmed, Scopus, and Cochrane Library database for all cases of lateral ventricular liponeurocytoma. A case illustration complements this review.ResultsThe described cases from 1997 onward include 14 cases that have been published in full papers in the English literature. Six additional cases are reported in short English abstracts in full non-English papers, and one case was described in a central neurocytoma report. There is a definite male predominance of 70% (14 male) and a mean age of 37 years (range 24–62). Heterogenous enhancement and signals in magnetic resonant images (MRI) are the radiological characteristics. In all reported cases, the presence of lipocytes and fat vacuoles is considered the paramount histopathological feature. Total surgical resection was achieved in 80% (12 out of 15) of the cases. Only two cases (including ours) received radiation therapy. Recurrence was seen in two patients during follow-up that was treated by radiation therapy in one and surgery in the other. The proliferation index is mostly below 5% in all cases, with the Ki-67 range between < 1% to 10%.ConclusionsLateral ventricular liponeurocytoma has been treated effectively by surgical resection in a limited number of cases. The decision for radiation therapy is based on a high proliferation index and tumor recurrence.  相似文献   
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BackgroundSerum neurofilament light chain (sNfL) is a promising biomarker for neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS), but there is limited validation data in specific ethnic and disease groups.ObjectiveTo investigate the levels of sNfL in a cohort of Chinese patients with NMOSD and compare sNfL levels in patients with different disease courses and treatments.MethodsWe analysed sNfL levels in 153 Chinese patients with NMOSD (n = 51) and MS (n = 102) using single-molecule array (Simoa) technology. The sNfL levels were compared with those of 71 healthy controls from two centres in southern China. For each disease, we assessed correlations between sNfL and disease phases and treatments.ResultsHigher levels of sNfL were found in the patients with NMOSD [17.97 (10.55–27.94) pg/mL] and MS [15.83 (8.92–25.67) pg/mL] compared to healthy controls [10.09 (7.19–13.29) pg/mL, p < 0.001]. No significant differences were found between the AQP4-IgG-positive NMOSD group and OCB-positive MS group.ConclusionssNfL measured by Simoa technology is a potential candidate blood biomarker for the diagnosis and disease monitoring of NMOSD in Chinese patients, warranting further prospective and multicentre studies.  相似文献   
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A principal characteristic of the mammalian visual system is its high capacity for plasticity in early postnatal development during a time commonly referred to as the critical period. The progressive diminution of plasticity with age is linked to the emergence of a collection of molecules called molecular brakes that reduce plasticity and stabilize neural circuits modified by earlier visual experiences. Manipulation of braking molecules either pharmacologically or though experiential alteration enhances plasticity and promotes recovery from visual impairment. The stability of neural circuitry is increased by intermediate filamentous proteins of the cytoskeleton such as neurofilaments and α‐internexin. We examined levels of these intermediate filaments within cat and human primary visual cortex (V1) across development to determine whether they accumulate following a time course consistent with a molecular brake. In both species, levels of intermediate filaments increased considerably throughout early postnatal life beginning shortly after the peak of the critical period, with the highest levels measured in adults. Neurofilament phosphorylation was also observed to increase throughout development, raising the possibility that posttranslational modification by phosphorylation reduces plasticity due to increased protein stability. Finally, an approach to scale developmental time points between species is presented that compares the developmental profiles of intermediate filaments between cats and humans. Although causality between intermediate filaments and plasticity was not directly tested in this study, their accumulation relative to the critical period indicates that they may contribute to the decline in plasticity with age, and may also constrain the success of treatments for visual disorders applied in adulthood. J. Comp. Neurol. 523:2111–2126, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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目的: 探讨血清神经丝轻链蛋白(neurofilament light chain protein,NFL)是否可以作为预测阿尔茨海默病(Alzheimer''s disease,AD)早期的外周血生物标志物。 方法: 纳入新疆医科大学附属中医医院阿尔茨海默病临床数据库的AD患者50例,遗忘型轻度认知功能障碍(amnestic mild cognitive impairment,aMCI)患者50例,以及选择同一时间段内按年龄、文化程度相匹配的健康对照者(cognitively normal,CN)50例,受试者均采集血清,采用酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)检测血清NFL水平。 结果: ①AD、aMCI与CN患者的年龄、教育年限、体质指数(body mass index,BMI)比较均无统计学差异(P>0.05),资料具有可比性。②AD患者简易精神状态检查量表(mini-mental state examination,MMSE)、蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)评分显著低于aMCI组和CN组[AD组(17.48±7.50),aMCI组(25.56±1.63),CN组(28.60±1.09);F=81.830,P=0.000],MoCA评分差异最明显[AD组(12.04±6.31),aMCI组(19.92±3.17),CN组(27.62±1.16);F=177.187,P=0.000]。③血清NFL水平[AD组(4.486±2.463)ng/mL,aMCI组(5.101±2.172)ng/mL,CN组(2.885±1.469)ng/mL,F=15.167,P=0.000],AD组和aMCI组NFL水平显著高于CN组,其中aMCI组最高,3组间比较具有统计学差异;应用Spearman相关性分析发现3组间年龄、MMSE评分、MoCA评分、日常生活能力量表评分(activity of dai1y living scale,ADL)、临床痴呆评定量表(clinical dementia rating,CDR)评分与NFL水平没有相关性(P>0.05)。 结论: 轻度认知功能障碍患者血清NFL水平最高,提示血清NFL也许是预测阿尔茨海默病早期的外周血生物标志物。  相似文献   
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The claustrum (CLA) is a subcortical structure that is reciprocally and topographically connected with the cerebral cortex. The complexity of the cerebral cortex varies dramatically across mammals, raising the question of whether there might also be differences in CLA organization, circuitry, and function. Species variations in the shape of the CLA are well documented. Studies in multiple species have identified subsets of neurochemically distinct interneurons; some data suggest species variations in the nature, distribution, and numbers of different neurochemically identified neuronal types. We have studied the CLA in a smooth-brained primate, the squirrel monkey, using Nissl-stained sections and immunohistochemistry. We found that the shape of the CLA is different from that in other primates. We found several different neurochemically defined populations of neurons equally distributed throughout the CLA. Immunoreactivity to GAD65/67 and GABAA receptors suggest that GABAergic interneurons provide widespread inhibitory input to CLA neurons. Immunoreactivity to glutamate transporters suggests widespread and overlapping excitatory input from cortical and possibly subcortical sources. Comparison of CLA organization in different species suggests that there may be major species differences both in the organization and in the functions of the CLA. Anat Rec, 303:1439–1454, 2020. © 2019 American Association for Anatomy  相似文献   
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Glutaric Aciduria type I (GA-I) is caused by mutations in the GCDH gene. Its deficiency results in accumulation of the key metabolites glutaric acid (GA) and 3-hydroxyglutaric acid (3-OHGA) in body tissues and fluids. Present knowledge on the neuropathogenesis of GA-I suggests that GA and 3-OHGA have toxic properties on the developing brain.We analyzed morphological and biochemical features of 3D brain cell aggregates issued from Gcdh?/? mice at two different developmental stages, day-in-vitro (DIV) 8 and 14, corresponding to the neonatal period and early childhood. We also induced a metabolic stress by exposing the aggregates to 10 mM l-lysine (Lys).Significant amounts of GA and 3-OHGA were detected in Gcdh?/? aggregates and their culture media. Ammonium was significantly increased in culture media of Gcdh?/? aggregates at the early developmental stage. Concentrations of GA, 3-OHGA and ammonium increased significantly after exposure to Lys. Gcdh?/? aggregates manifested morphological alterations of all brain cell types at DIV 8 while at DIV 14 they were only visible after exposure to Lys. Several chemokine levels were significantly decreased in culture media of Gcdh?/? aggregates at DIV 14 and after exposure to Lys at DIV 8.This new in vitro model for brain damage in GA-I mimics well in vivo conditions. As seen previously in WT aggregates exposed to 3-OHGA, we confirmed a significant ammonium production by immature Gcdh?/? brain cells. We described for the first time a decrease of chemokines in Gcdh?/? culture media which might contribute to brain cell injury in GA-I.  相似文献   
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Cardiac reflexes originating from sensory receptors in the heart ensure blood supply to vital tissues and organs in the face of constantly changing demands. Atrial volume receptors are mechanically sensitive vagal afferents which relay to the medulla and hypothalamus, affecting vasopressin release and renal sympathetic activity. To date, two anatomically distinct sensory endings have been identified which may subserve cardiac mechanosensation: end-nets and flower-spray endings. To map the distribution of atrial receptors in the subendocardial space, we have double-labelled rat right atrial whole mounts for neurofilament heavy chain (NFH) and synaptic vesicle protein 2 (SV2) and generated high-resolution maps of the rat subendocardial neural plexus at the cavo-atrial region. In order to elucidate the nature of these fibres, double labelling with synaptophysin (SYN) and either NFH, calcitonin gene-related peptide (CGRP), choline acetyltransferase (ChAT) or tyrosine hydroxylase (TH) was performed. The findings show that subendocardial nerve nets are denser at the superior cavo-atrial junction than the mid-atrial region. Adluminal plexuses had the finest diameters and stained positively for synaptic vesicles (SV2 and SYN), CGRP and TH. These plexuses may represent sympathetic post-ganglionic fibres and/or sensory afferents. The latter are candidate substrates for type B volume receptors which are excited by stretch during atrial filling. Deeper nerve fibres appeared coarser and may be cholinergic (positive staining for ChAT). Flower-spray endings were never observed using immunohistochemistry but were delineated clearly with the intravital stain methylene blue. We suggest that differing nerve fibre structures form the basis by which atrial deformation and hence atrial filling is reflected to the brain.  相似文献   
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