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991.
992.
The diabetes drug liraglutide reverses cognitive impairment in mice and attenuates insulin receptor and synaptic pathology in a non‐human primate model of Alzheimer's disease 下载免费PDF全文
Andre F Batista Leticia Forny‐Germano Julia R Clarke Natalia M Lyra e Silva Jordano Brito‐Moreira Susan E Boehnke Andrew Winterborn Brian C Coe Ann Lablans Juliana F Vital Suelen A Marques Ana MB Martinez Matthias Gralle Christian Holscher William L Klein Jean‐Christophe Houzel Sergio T Ferreira Douglas P Munoz Fernanda G De Felice 《The Journal of pathology》2018,245(1):85-100
Alzheimer's disease (AD) is a devastating neurological disorder that still lacks an effective treatment, and this has stimulated an intense pursuit of disease‐modifying therapeutics. Given the increasingly recognized link between AD and defective brain insulin signaling, we investigated the actions of liraglutide, a glucagon‐like peptide‐1 (GLP‐1) analog marketed for treatment of type 2 diabetes, in experimental models of AD. Insulin receptor pathology is an important feature of AD brains that impairs the neuroprotective actions of central insulin signaling. Here, we show that liraglutide prevented the loss of brain insulin receptors and synapses, and reversed memory impairment induced by AD‐linked amyloid‐β oligomers (AβOs) in mice. Using hippocampal neuronal cultures, we determined that the mechanism of neuroprotection by liraglutide involves activation of the PKA signaling pathway. Infusion of AβOs into the lateral cerebral ventricle of non‐human primates (NHPs) led to marked loss of insulin receptors and synapses in brain regions related to memory. Systemic treatment of NHPs with liraglutide provided partial protection, decreasing AD‐related insulin receptor, synaptic, and tau pathology in specific brain regions. Synapse damage and elimination are amongst the earliest known pathological changes and the best correlates of memory impairment in AD. The results illuminate mechanisms of neuroprotection by liraglutide, and indicate that GLP‐1 receptor activation may be harnessed to protect brain insulin receptors and synapses in AD. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
993.
Everton Cazzo Fabio de Felice Gallo José Carlos Pareja Elinton Adami Chaim 《Obesity surgery》2014,24(4):666-668
Nonalcoholic fatty liver disease (NAFLD) has become an important health issue lately. The aim of this study is to determine its prevalence among obese subjects which undergo Roux-en-Y gastric bypass (RYGB). It is a cross-sectional retrospective study involving 164 subjects who underwent RYGB. Clinical, biochemical, and histopathologic features were evaluated. The most common histopathologic features observed were steatohepatitis with fibrosis (29.9 %) and isolated fibrosis (29.3 %). Increased alkaline phosphatase was associated to NAFLD. Dyslipidemia and type 2 diabetes mellitus were associated to NAFLD. Ultrasound had a global accuracy of 78 % to detect NAFLD. Higher prevalence of severe forms of NAFLD was observed compared to previous reports. Most routine biochemical studies had poor correlation with NAFLD and ultrasound was useful but not definitive to detect NAFLD. 相似文献
994.
J. S. Bonano R. A. Glennon L. J. De Felice M. L. Banks S. S. Negus 《Psychopharmacology》2014,231(1):199-207
Rationale
Abuse of synthetic cathinones, popularized as “bath salts,” has increased dramatically in the USA since their debut in 2010. Preclinical behavioral studies may clarify determinants of the abuse-related effects produced by these compounds.Objectives
This study examined behavioral effects of (±)-methcathinone, (±)-3,4-methylenedioxypyrovalerone (MDPV), (±)-3,4-methylenedioxymethcathinone (methylone), and (±)-4-methylmethcathinone (mephedrone) in rats using intracranial self-stimulation (ICSS).Methods
Male Sprague–Dawley rats (n?=?18) with electrodes targeting the medial forebrain bundle responded for multiple frequencies of brain stimulation and were tested in two phases. First, dose–effect curves for methcathinone (0.1–1.0 mg/kg), MDPV (0.32–3.2 mg/kg), methylone (1.0–10 mg/kg), and mephedrone (1.0–10 mg/kg) were determined. Second, time courses were determined for effects produced by the highest dose of each compound.Results
Methcathinone produced dose- and time-dependent facilitation of ICSS. MDPV, methylone, and mephedrone produced dose- and time-dependent increases in low rates of ICSS maintained by low brain stimulation frequencies, but also produced abuse-limiting depression of high ICSS rates maintained by high brain stimulation frequencies. Efficacies to facilitate ICSS were methcathinone ≥ MDPV ≥ methylone > mephedrone. Methcathinone was the most potent compound, and MDPV was the longest acting compound.Conclusions
All compounds facilitated ICSS at some doses and pretreatment times, which is consistent with abuse liability for each of these compounds. However, efficacies of compounds to facilitate ICSS varied, with methcathinone displaying the highest efficacy and mephedrone displaying the lowest efficacy to facilitate ICSS. 相似文献995.
996.
Lisa Maccari Augusto Pasini Emanuela Caroli Caterina Rosa Andrea Marotta Diana Martella Luis J. Fuentes Maria Casagrande 《Journal of autism and developmental disorders》2014,44(11):2871-2881
This study assessed visual search abilities, tested through the flicker task, in children diagnosed with autism spectrum disorders (ASDs). Twenty-two children diagnosed with ASD and 22 matched typically developing (TD) children were told to detect changes in objects of central interest or objects of marginal interest (MI) embedded in either emotion-laden (positive or negative) or neutral real-world pictures. The results showed that emotion-laden pictures equally interfered with performance of both ASD and TD children, slowing down reaction times compared with neutral pictures. Children with ASD were faster than TD children, particularly in detecting changes in MI objects, the most difficult condition. However, their performance was less accurate than performance of TD children just when the pictures were negative. These findings suggest that children with ASD have better visual search abilities than TD children only when the search is particularly difficult and requires strong serial search strategies. The emotional–social impairment that is usually considered as a typical feature of ASD seems to be limited to processing of negative emotional information. 相似文献
997.
Ruizhong Wang Tamara King Milena De Felice Wenhong Guo Michael H. Ossipov Frank Porreca 《The journal of pain》2013,14(8):845-853
Neuropathic pain is frequently characterized by spontaneous pain (ie, pain at rest) and, in some cases, by cold- and touch-induced allodynia. Mechanisms underlying the chronicity of neuropathic pain are not well understood. Rats received spinal nerve ligation (SNL) and were monitored for tactile and thermal thresholds. While heat hypersensitivity returned to baseline levels within approximately 35 to 40 days, tactile hypersensitivity was still present at 580 days after SNL. Tactile hypersensitivity at post-SNL day 60 (D60) was reversed by microinjection of 1) lidocaine; 2) a cholecystokinin 2 receptor antagonist into the rostral ventromedial medulla; or 3) dorsolateral funiculus lesion. Rostral ventromedial medulla lidocaine at D60 or spinal ondansetron, a 5-hydroxytryptamine 3 antagonist, at post-SNL D42 produced conditioned place preference selectively in SNL-treated rats, suggesting long-lasting spontaneous pain. Touch-induced FOS was increased in the spinal dorsal horn of SNL rats at D60 and prevented by prior dorsolateral funiculus lesion, suggesting that long-lasting tactile hypersensitivity depends upon spinal sensitization, which is mediated in part by descending facilitation, in spite of resolution of heat hypersensitivity.PerspectiveThese data suggest that spontaneous pain is present for an extended period of time and, consistent with likely actions of clinically effective drugs, is maintained by descending facilitation. 相似文献
998.
Patrizio Tatti Felice Strollo Desiderio Passali 《Journal of diabetes science and technology》2013,7(3):743-748
Background
Disturbed sleep and nocturnal altered breathing are related to disturbances of glucose metabolism. The present uncontrolled observational study explores the role of these factors on the variability of fasting glycemia.Methods
The number and duration of nocturnal awakenings and the fasting glycemia of 97 patients with type 2 diabetes treated with diet, metformin, or gliptins were recorded over seven consecutive days. During the same time period, the main respiratory indexes—oxygen disturbance index, apnea/hypopnea index, and respiratory disturbance index—were recorded for one night.Results
The three respiratory indexes and the number of nocturnal awakenings are highly correlated with the coefficient of variation of the fasting blood glucose recorded over the 7-day period at p <.005 level. A multiple regression analysis showed that the variables in the model explained 86% of the variability.Results
Respiratory/sleep disturbances appear to be modulators superimposed on blood glucose levels determined by other factors. 相似文献999.
Rafael Vital Costa Luanda André Collange Grecco Hugo Pasini Neto Renata Calhes Franco de Moura Jo?o Carlos Ferrari Correa Fernanda Ishida Corrêa Claudia Santos Oliveira 《Journal of Physical Therapy Science》2013,25(8):1001-1005
[Purpose] The aim of this study was to develop and assess the applicability of an
experimental ankle-foot orthosis during gait in patients with hemiparesis. [Subjects and
Methods] This was a noncontrolled cross-sectional study. Ten adult patients with
hemiparesis but who were capable of independent gait were included in the study. Gait
assessment was performed using two platforms (EMG System do Brasil), an electromyograph
(EMG System do Brasil), and a video camera. The experimental orthosis consisted of a
single piece that fit over the foot and 1/3 of the distal tibia and had a steel spring.
[Results] There was greater activation of the rectus femoris and vastus lateralis muscles
in the stance and mid-stance phases with the use of the experimental ankle-foot orthosis
in comparison with the use of a polypropylene ankle-foot orthosis and no orthosis.
Regarding spatial and temporal gait parameters, the individuals achieved an increase in
stride length with the use of the experimental ankle-foot orthosis in comparison with the
use of a polypropylene ankle-foot orthosis. [Conclusion] The results of the present study
demonstrate that individuals with hemiparesis achieved an improvement in the stance and
mid-stance phases of gait with the use of the experimental ankle-foot orthosis.Key words: Orthosis, Hemiparesis, Gait 相似文献
1000.
Roberto Malagò Andrea Pezzato Camilla Barbiani Domenico Tavella Paola Vallerio Anna Fratta Pasini Luciano Cominacini Roberto Pozzi Mucelli 《La Radiologia medica》2013,118(8):1294-1308