全文获取类型
收费全文 | 27018篇 |
免费 | 1252篇 |
国内免费 | 68篇 |
专业分类
耳鼻咽喉 | 654篇 |
儿科学 | 1135篇 |
妇产科学 | 398篇 |
基础医学 | 2926篇 |
口腔科学 | 552篇 |
临床医学 | 1639篇 |
内科学 | 7212篇 |
皮肤病学 | 1080篇 |
神经病学 | 1848篇 |
特种医学 | 698篇 |
外科学 | 4119篇 |
综合类 | 113篇 |
一般理论 | 6篇 |
预防医学 | 2206篇 |
眼科学 | 747篇 |
药学 | 1540篇 |
中国医学 | 68篇 |
肿瘤学 | 1397篇 |
出版年
2023年 | 131篇 |
2022年 | 81篇 |
2021年 | 581篇 |
2020年 | 249篇 |
2019年 | 668篇 |
2018年 | 1041篇 |
2017年 | 617篇 |
2016年 | 528篇 |
2015年 | 575篇 |
2014年 | 598篇 |
2013年 | 964篇 |
2012年 | 1743篇 |
2011年 | 1918篇 |
2010年 | 1015篇 |
2009年 | 739篇 |
2008年 | 1582篇 |
2007年 | 1747篇 |
2006年 | 1591篇 |
2005年 | 1638篇 |
2004年 | 1473篇 |
2003年 | 1457篇 |
2002年 | 1412篇 |
2001年 | 1083篇 |
2000年 | 1353篇 |
1999年 | 990篇 |
1998年 | 134篇 |
1997年 | 91篇 |
1996年 | 103篇 |
1995年 | 66篇 |
1994年 | 45篇 |
1993年 | 48篇 |
1992年 | 330篇 |
1991年 | 245篇 |
1990年 | 200篇 |
1989年 | 151篇 |
1988年 | 155篇 |
1987年 | 154篇 |
1986年 | 119篇 |
1985年 | 110篇 |
1984年 | 83篇 |
1983年 | 61篇 |
1981年 | 31篇 |
1979年 | 54篇 |
1976年 | 31篇 |
1974年 | 31篇 |
1973年 | 34篇 |
1972年 | 29篇 |
1971年 | 27篇 |
1970年 | 25篇 |
1968年 | 28篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
M D Paz-Caballero E García-Austt 《Electroencephalography and clinical neurophysiology》1992,82(5):369-376
Event-related potential (ERP) components associated with target stimulus selection in a double discrimination visual task were studied. The experimental paradigm consisted in the presentation of low intensity stimuli that varied according to two physical features: geometrical form (squares and circles) and location (a spot in different positions inside the stimulus). Subjects performed 3 tasks on these stimuli: control task in which they looked passively at the stimuli, and 2 discrimination tasks, in which they had to respond to a certain stimulus (a specific conjunction of form and spot location). The early components (P1 and N1) obtained in the control and discrimination tasks were associated with sensory analysis of simple stimulus features. Relevance of a particular feature modified the latency and/or the area of these components. The longer-latency components (N2 and P3) were elicited only in the discrimination tasks. N2 was associated with target stimulus selection because its area was significantly larger for target stimuli and because its "offset" latency correlated with choice reaction time. Results are discussed and contrasted with various models of target selection. 相似文献
992.
Faustino Núñez-Batalla Gabriela Vasile Noelia Cartón-Corona Daniel Pedregal-Mallo Marta Menéndez de Castro Maite Guntín García Justo Gómez-Martínez Pilar Carro Fernández Jose Luis Llorente-Pendás 《Acta otorrinolaringologica espanola》2019,70(5):251-257
Introduction and objectivesInadequate auditory feedback in prelingually deaf children alters the articulation of consonants and vowels.The purpose of this investigation was to compare vowel production in Spanish-speaking deaf children with cochlear implantation, and with hearing-aids with normal-hearing children by means of acoustic analysis of formant frequencies and vowel space.MethodsA total of 56 prelingually deaf children (25 with cochlear implants and 31 wearing hearing-aids) and 47 normal-hearing children participated. The first 2 formants (F1 and F2) of the five Spanish vowels were measured using Praat software. One-way analysis of variance (ANOVA) and post hoc Scheffé test were applied to analyze the differences between the 3 groups. The surface area of the vowel space was also calculated.ResultsThe mean value of F1 in all vowels was not significantly different between the 3 groups. For vowels /i/, /o/ and /u/, the mean value of F2 was significantly different between the 2 groups of deaf children and their normal-hearing peers.ConclusionBoth prelingually hearing-impaired groups tended toward subtle deviations in the articulation of vowels that could be analyzed using an objective acoustic analysis programme. 相似文献
993.
Faustino Núñez-Batalla Noelia Cartón-Corona Gabriela Vasile Patricia García-Cabo Laura Fernández-Vañes José Luis Llorente-Pendás 《Acta otorrinolaringologica espanola》2019,70(4):222-228
Introduction and objectivesPerceptual rating of overall voice quality and other more specific perceptual dimensions is difficult, as such judgments depend on the listener's subjectivity. Thus, finding objective, valid, and accessible clinical measures to include in comprehensive voice evaluation protocols is a priority.The purposes of this study were to 1) determine the diagnostic accuracy of a single acoustic measure, smoothed cepstral peak prominence (CPPS), to predict voice disorder status from sustained vowels and connected speech samples using the software Praat; 2) to determine the relationship between measures of CPPS and perceptual ratings of vocal quality; and 3) describe the normative values of CPPS.MethodMeasures of CPPS were obtained from connected speech and sustained vowel recordings of 72 Spanish-speaking subjects with voice disorders and 52 nondysphonic Spanish-speaking subjects with no vocal disorders using freely downloadable Praat software. IBM SPSS Statistics software version 23 was used to complete the statistical analyses.Resultsresults revealed a 70% sensitivity rate, a specificity rate of 85%. Estimated severity for sustained vowels and connected speech were strongly correlated and significantly associated with listener ratings of dysphonia severity.ConclusionsA single acoustic measure of CPPS was highly predictive of voice disorder status using Praat software. Clinicians may consider using CPPS to complement clinical voice evaluation and screening protocols. 相似文献
994.
Alberto E. Paniz‐Mondolfi MD MSc FFTM RCPS Carolina Talhari MD María F García Bustos MD PhD Tamara Rosales MD Wilmer E. Villamil‐Gomez MD Marilianna Marquez BSc Alexandra M. Pérez Alvarez Lic Biol Alejandra I. Tálamo Sánchez BSc 《International journal of dermatology》2017,56(12):1328-1341
Infant and young child skin diseases are among the most common features of morbidity throughout the tropics. Because the skin is directly exposed to the environment, it is considerably affected by climatic and local conditions such as vectors and microorganisms, as in the case of leishmaniasis. In America the observed magnitude of cutaneous leishmaniasis in children has led to the study of increased risk of exposure of this group due to the possibility of peri‐ and intradomiciliary transmission. The present review pretends to make a concrete approach all through the broad and main figures of this parasitic disease, including the clinical, physiopathological, epidemiological, diagnostic, and therapeutic aspects, in order to be used as a practical source of reference for pediatricians leading with tropical cutaneous pathology in the region. 相似文献
995.
996.
997.
998.
Enrique Sanchis-Sánchez Enrique Lluch-Girbés Pepe Guillart-Castells Sylvia Georgieva Pablo García-Molina Jose-María Blasco 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2021,25(2):117-134
ObjectiveTo determine the effectiveness of mechanical diagnosis and therapy (MDT) in patients with chronic low back pain (CLBP) compared to other traditional physical therapy interventions.MethodsRandomized controlled trials investigating the effect of MDT compared to other traditional physical therapy interventions in individuals with CLBP were considered eligible. For the purpose of this review, MDT was compared to active and passive physical therapy interventions. Independent reviewers assessed the eligibility of studies, extracted data, and assessed the risk of bias. The primary outcomes investigated were pain and disability.ResultsFourteen studies were included in the review. Of these, 11 provided data to be included in the meta-analyses. Our findings showed that MDT was no more effective in decreasing pain (standardized mean difference [SMD] = 0.01, 95% confidence interval [CI]: ?0.44, 0.46) and disability (SMD = 0.08, 95% CI: ?0.53, 0.68) than other active treatments. Similar results were found when comparing MDT to other passive treatments for pain (SMD = ?0.39, 95% CI: ?0.90, 0.11) and disability (SMD = ?0.13, 95% CI: ?0.29, 0.03).ConclusionThere is low to moderate quality evidence that MDT is not superior than other traditional physical therapy interventions in improving pain and disability in people with CLBP. 相似文献
999.
1000.
R. Navarro E. Vilarrasa P. Herranz L. Puig X. Bordas J.M. Carrascosa R. Taberner M. Ferrán M. García‐Bustinduy A. Romero‐Maté R. Pedragosa A. García‐Diez E. Daudén 《The British journal of dermatology》2013,168(3):609-616
Background Both the safety and efficacy of biologic therapy may be affected in the presence of highly prevalent chronic viral hepatitis. Objectives To evaluate the safety and effectiveness of ustekinumab and antitumour necrosis factor therapy in patients with psoriasis and concomitant chronic viral hepatitis. Methods This was a retrospective, multicentre study. Twenty‐five patients with psoriasis and concurrent hepatitis C virus (HCV) (20 patients) or hepatitis B virus (HBV) (five patients) infection who had received at least one biologic agent (etanercept, 21 treatments; adalimumab, four; ustekinumab, four; infliximab, two) were included. Clinical, imaging and laboratory data were recorded. Results In the case of HCV infection, the majority of the patients did not exhibit increases in their viral load or serum liver tests. Aspartate aminotransferase, alanine aminotransferase and gamma glutamyl transpeptidase were doubled from the baseline measurement in only one patient treated with etanercept. Two other cases exhibited viral load increases during the follow‐up period. In total, 18 of the 26 treatments achieved a 75% improvement in their Psoriasis Area and Severity Index (PASI 75) score during the follow‐up period. Two patients treated with etanercept were diagnosed with hepatocellular carcinoma. In the case of HBV infection, all of the patients were being treated with antiviral therapy, and none presented significant variations in viral load or serum liver enzymes. All patients achieved a PASI 75 during follow‐up. Conclusions Biologic therapy was effective and safe for the majority of our patients with HCV and HBV infection, although there may be a risk of reactivation or aggravation. We describe the first cases to receive ustekinumab. The use of biologics should be limited to those cases in which the risk–benefit ratio is justified. 相似文献