全文获取类型
收费全文 | 1974篇 |
免费 | 129篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 39篇 |
妇产科学 | 71篇 |
基础医学 | 238篇 |
口腔科学 | 241篇 |
临床医学 | 126篇 |
内科学 | 394篇 |
皮肤病学 | 43篇 |
神经病学 | 188篇 |
特种医学 | 40篇 |
外科学 | 136篇 |
综合类 | 9篇 |
预防医学 | 212篇 |
眼科学 | 107篇 |
药学 | 127篇 |
中国医学 | 26篇 |
肿瘤学 | 82篇 |
出版年
2023年 | 17篇 |
2022年 | 27篇 |
2021年 | 91篇 |
2020年 | 61篇 |
2019年 | 78篇 |
2018年 | 84篇 |
2017年 | 52篇 |
2016年 | 71篇 |
2015年 | 82篇 |
2014年 | 97篇 |
2013年 | 127篇 |
2012年 | 158篇 |
2011年 | 177篇 |
2010年 | 69篇 |
2009年 | 68篇 |
2008年 | 141篇 |
2007年 | 162篇 |
2006年 | 92篇 |
2005年 | 99篇 |
2004年 | 90篇 |
2003年 | 56篇 |
2002年 | 34篇 |
2001年 | 22篇 |
2000年 | 32篇 |
1999年 | 23篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 8篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1975年 | 2篇 |
1974年 | 8篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 5篇 |
1969年 | 3篇 |
1968年 | 8篇 |
1967年 | 2篇 |
1965年 | 2篇 |
排序方式: 共有2111条查询结果,搜索用时 625 毫秒
51.
Wiemels JL Xiao Z Buffler PA Maia AT Ma X Dicks BM Smith MT Zhang L Feusner J Wiencke J Pritchard-Jones K Kempski H Greaves M 《Blood》2002,99(10):3801-3805
Recent reports have established the prenatal origin of leukemia translocations and resultant fusion genes in some patients, including MLL-AF4 translocations in infants and TEL-AML1 translocations in children. We now report evidence for the prenatal origin of a translocation in childhood acute myeloid leukemia (AML). The t(8;21) AML1-ETO translocations were sequenced at the genomic level in 10 diagnostic leukemia samples from children with available neonatal Guthrie blood spots. Clonotypic genomic AML1-ETO sequences were detected in the Guthrie spots for 5 individuals, providing unambiguous evidence of prenatal origin in these cases. Two of these patients were older than 10 years of age at diagnosis, indicative of a protracted postnatal latency. Three of the patients were assessed for the persistence of genomic fusion sequences in complete clinical remission samples and were found to be positive. These data indicate that t(8;21) in childhood AML can arise in utero, possibly as an initiating event in childhood AML, and may establish a long-lived or stable parental clone that requires additional secondary genetic alterations to cause leukemia. 相似文献
52.
53.
Fernando G. Zampieri Theodore J. Iwashyna Elizabeth M. Viglianti Leandro U. Taniguchi William N. Viana Roberto Costa Thiago D. Corrêa Carlos Eduardo N. Moreira Marcelo O. Maia Giulliana M. Moralez Thiago Lisboa Marcus A. Ferez Carlos Eduardo F. Freitas Clayton B. de Carvalho Bruno F. Mazza Mariza F. A. Lima Grazielle V. Ramos Aline R. Silva Fernando A. Bozza Jorge. I. F. Salluh Marcio Soares for the ORCHESTRA Study Investigators 《Intensive care medicine》2018,44(9):1512-1520
Purpose
Frail patients are known to experience poor outcomes. Nevertheless, we know less about how frailty manifests itself in patients’ physiology during critical illness and how it affects resource use in intensive care units (ICU). We aimed to assess the association of frailty with short-term outcomes and organ support used by critically ill patients.Methods
Retrospective analysis of prospective collected data from 93 ICUs in Brazil from 2014 to 2015. We assessed frailty using the modified frailty index (MFI). The primary outcome was in-hospital mortality. Secondary outcomes were discharge home without need for nursing care, ICU and hospital length of stay (LOS), and utilization of ICU organ support and transfusion. We used mixed logistic regression and competing risk models accounting for relevant confounders in outcome analyses.Results
The analysis consisted of 129,680 eligible patients. There were 40,779 (31.4%) non-frail (MFI?=?0), 64,407 (49.7%) pre-frail (MFI?=?1–2) and 24,494 (18.9%) frail (MFI?≥?3) patients. After adjusted analysis, frailty was associated with higher in-hospital mortality (OR 2.42, 95% CI 1.89–3.08), particularly in patients admitted with lower SOFA scores. Frail patients were less likely to be discharged home (OR 0.36, 95% CI 0.54–0.79) and had higher hospital and ICU LOS than non-frail patients. Use of all forms of organ support (mechanical ventilation, non-invasive ventilation, vasopressors, dialysis and transfusions) were more common in frail patients and increased as MFI increased.Conclusions
Frailty, as assessed by MFI, was associated with several patient-centered endpoints including not only survival, but also ICU LOS and organ support.54.
Carlos José Moraes Dias Luana Monteiro Anaisse Azoubel Herikson Araújo Costa Ednei Costa Maia Bruno Rodrigues Antonio Carlos Silva‐Filho Carlos Alberto Alves Dias‐Filho Maria Claúdia Irigoyen Richard D Leite Mário Sevilio de Oliveira Junior Cristiano Teixeira Mostarda 《Clinical and experimental pharmacology & physiology》2015,42(12):1239-1244
Modulation of the autonomic nervous system on heart rate can be compromised in chronic kidney disease and may result in changes in the frequency and duration of the cardiac cycle. The aim of this study was to evaluate autonomic modulation in active and sedentary renal transplant recipients. Twenty renal‐transplanted individuals were analyzed at the Centro de Prevenção de Doenças Renais (Kidney Disease Education Centre), in the academic hospital of Universidade Federal do Maranhão, and were divided into the active group (AG) and the sedentary group (SG). The AG comprised of six men and four women (age 43.10 ± 13.02) and was in regular concurrent training intervention for 8 weeks, while the SG was composed of three men and seven women (age 36.8 ± 9.26). Analysis of heart rate (HR) variability in time and frequency domain demonstrated that HR mean values in the SG and AG were 787.32 ± 79.60 and 870 ± 106.66 ms, respectively. Differences were observed in the time domain and frequency domain. The total index of low frequency and high frequency showed no differences between the SG and AG. Biochemical variables presented significantly lower levels after 8 weeks of training. Higher heart rate variability in the time domain and greater vagal modulation was observed in the AG. The AG ad greater vagal modulation when compared to the SG, with removal of the sympathetic and increased parasympathetic in the behaviour was confirmed by sympatho‐vagal balance. The AG also presented significant improvements in the frequency domain. 相似文献
55.
56.
Mariel A. Marlow Ethel Leonor Noia Maciel Carolina Maia Martins Sales Teresa Gomes Robert E. Snyder Regina Paiva Daumas Lee W. Riley 《Journal of urban health》2015,92(4):622-634
To quantitatively assess disease burden due to tuberculosis between populations residing in and outside of urban informal settlements in Rio de Janeiro, Brazil, we compared disability-adjusted life years (DALYs), or “DALY-gap.” Using the 2010 Brazilian census definition of informal settlements as aglomerados subnormais (AGSN), we allocated tuberculosis (TB) DALYs to AGSN vs non-AGSN census tracts based on geocoded addresses of TB cases reported to the Brazilian Information System for Notifiable Diseases in 2005 and 2010. DALYs were calculated based on the 2010 Global Burden of Disease methodology. DALY-gap was calculated as the difference between age-adjusted DALYs/100,000 population between AGSN and non-AGSN. Total TB DALY in Rio in 2010 was 16,731 (266 DALYs/100,000). DALYs were higher in AGSN census tracts (306 vs 236 DALYs/100,000), yielding a DALY-gap of 70 DALYs/100,000. Attributable DALY fraction for living in an AGSN was 25.4 %. DALY-gap was highest for males 40–59 years of age (501 DALYs/100,000) and in census tracts with <60 % electricity (12,327 DALYs/100,000). DALY-gap comparison revealed spatial and quantitative differences in TB burden between slum vs non-slum census tracts that were not apparent using traditional measures of incidence and mortality. This metric could be applied to compare TB burden or burden for other diseases in mega-cities with large informal settlements for more targeted resource allocation and evaluation of intervention programs. 相似文献
57.
Vale Paula D. Silva Livia T. M. de Oliveira Edna Maria M. de Miranda Ricardo F. C. da Silva Renato David Araújo Lielia M. C. da Silva Samuel M. P. Cunha Wanessa C. Neto José S. Péres Ayrton K. Seixas Tamer N. da Rocha Jairo M. Margalho Carla S. Maia Henrique Cesar de A. 《Journal of interventional cardiac electrophysiology》2022,63(2):425-430
Journal of Interventional Cardiac Electrophysiology - Delineate retrospectively and prospectively the incidence and characteristics of transient ST-segment elevation during transseptal puncture.... 相似文献
58.
Two melanocortin receptors MC2-R (ACTH-receptor) and MC5-R are expressed in the adult lamb adrenal cortex. In this work, we have studied the time-course of expression of these two receptors during ovine fetal development. MC2-R expression progressively increases from day 60 to day 140 of gestation (x3), then more rapidly before parturition and remains constant in the newborn. In contrast, the pattern of MC5-R expression is totally different. A strong increase is observed between days 60 and 120 (x7) then followed by a decrease until parturition and after birth. This peak of MC5-R expression precedes that of MC2-R, suggesting that MC5-R might be involved in alpha-MSH- and/or ACTH-stimulated corticosteroid synthesis during early embryonic life. 相似文献
59.
Bentes Aline Almeida de Castro Romanelli Roberta Maia Marinho Paula Eillanny Silva Crispim Ana Paula Correa Loutfi Karina Soares Viegas Eisler Cristiane Carvalho Kroon Erna Geessien 《Journal of neurovirology》2021,27(4):609-615
Journal of NeuroVirology - This study aims to characterize the acute neurological manifestations caused by DENV, ZIKV, and YFV during hospitalization; identify the risk factors associated with... 相似文献
60.
Glauber Pacelli Gomes de Lima Terezinha Maria de Souza Gabrielle de Paula Freire Davi Felipe Farias Arcelina Pacheco Cunha Nágila Maria Pontes Silva Ricardo Selene Maia de Morais Ana Fontenele Urano Carvalho 《Parasitology research》2013,112(5):1953-1958
This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg?mL?1, larvicidal activity with LC50 ranging from 25.5 to 94.6 μg?mL?1, and pupicidal action with PC50 ranging from 276.8 to over 500 μg?mL?1. Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg?mL?1, respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50?>?6,000 mg.kg?1) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg?1, respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals. 相似文献