全文获取类型
收费全文 | 6759篇 |
免费 | 354篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 143篇 |
儿科学 | 141篇 |
妇产科学 | 107篇 |
基础医学 | 939篇 |
口腔科学 | 866篇 |
临床医学 | 465篇 |
内科学 | 1299篇 |
皮肤病学 | 154篇 |
神经病学 | 407篇 |
特种医学 | 123篇 |
外科学 | 747篇 |
综合类 | 13篇 |
一般理论 | 3篇 |
预防医学 | 859篇 |
眼科学 | 103篇 |
药学 | 486篇 |
中国医学 | 70篇 |
肿瘤学 | 231篇 |
出版年
2024年 | 12篇 |
2023年 | 70篇 |
2022年 | 168篇 |
2021年 | 314篇 |
2020年 | 201篇 |
2019年 | 249篇 |
2018年 | 321篇 |
2017年 | 209篇 |
2016年 | 253篇 |
2015年 | 251篇 |
2014年 | 358篇 |
2013年 | 371篇 |
2012年 | 584篇 |
2011年 | 684篇 |
2010年 | 367篇 |
2009年 | 242篇 |
2008年 | 429篇 |
2007年 | 383篇 |
2006年 | 310篇 |
2005年 | 272篇 |
2004年 | 225篇 |
2003年 | 191篇 |
2002年 | 180篇 |
2001年 | 88篇 |
2000年 | 88篇 |
1999年 | 62篇 |
1998年 | 20篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 11篇 |
1992年 | 28篇 |
1991年 | 25篇 |
1990年 | 16篇 |
1989年 | 18篇 |
1988年 | 12篇 |
1987年 | 15篇 |
1986年 | 13篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 9篇 |
1981年 | 4篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1970年 | 3篇 |
1969年 | 7篇 |
1968年 | 3篇 |
排序方式: 共有7156条查询结果,搜索用时 15 毫秒
101.
Clia Domingues Maria Joo Vidigal Ferreira Joana Moura Ferreira Ana Vera Marinho Patrícia Marques Alves Ctia Ferreira Isabel Fonseca Lino Gonalves 《Arquivos brasileiros de cardiologia》2021,116(5):928
Background:Although non-ischemic troponin elevation is frequently seen in patients admitted to the emergency department (ED), consensus regarding its management is lacking.Objectives:This study aimed to characterize patients admitted to the ED with non-ischemic troponin elevation and to identify potential mortality predictors in this population.Methods:This retrospective observational study included ED patients with a positive troponin test result between June and July of 2015. Patients with a clinical diagnosis of acute coronary syndrome (ACS) were excluded. Data on patient demographics and clinical and laboratory variables were extracted from medical records. Follow-up data were obtained for 16 months or until death occurred. The statistical significance level was 5%.Results:Troponin elevation without ACS was found in 153 ED patients. The median (IQR) patient age was 78 (19) years, 80 (52.3%) were female and 59(38.6%) died during follow-up. The median (IQR) follow-up period was 477(316) days. Survivors were significantly younger 76 (24) vs. 84 (13) years; p=0.004) and featured a higher proportion of isolated troponin elevation (without creatine kinase or myoglobin elevation) in two consecutive evaluations: 48 (53.9%) vs. 8 (17.4%), p<0.001. Survivors also presented a lower rate of antiplatelet treatment and same-day hospitalization. In the multivariate logistic regression with adjustment for significant variables in the univariate analysis, isolated troponin elevation in two consecutive evaluations showed a hazard ratio= 0.43 (95%CI 0.17–0.96, p=0.039); hospitalization, previous antiplatelet treatment and age remained independently associated with mortality.Conclusions:Isolated troponin elevation in two consecutive measurements was a strong predictor of survival in ED patients with troponin elevation but without ACS. 相似文献
102.
103.
104.
105.
A Specific Angiographic View of Left Coronary Artery Bifurcation in the Left Main Percutaneous Coronary Intervention Era
下载免费PDF全文
![点击此处可从《Journal of interventional cardiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Samir S. A. Reis M.D. Roberto V. Botelho M.D. Ph.D. Alexandre Abizaid M.D. Ph.D. Antônio D. S. Pereira M.D. Rodrigo Alves M.D. Denis F. de Souza R.N. Sebastião R. Ferreira‐Filho M.D. Ph.D. 《Journal of interventional cardiology》2016,29(3):293-299
Objectives
We propose a right lateral (90–120° RAO) with 30° cranial angiographic view to expose the bifurcation of the left main coronary artery (LMCA) when previously used routine projections were inefficient at clearly showing this region.Background
Little has been published in the medical literature regarding angiographic projections dedicated to special anatomies.Methods
A total of 84 patients were subjected to the proposed projections. A reproducibility study, conducted with the participation of 2 independent observers, judged the effectiveness of the proposed projection. The Prevalence and Bias Adjusted Kappa (PABAK) index, with a 95% confidence interval (CI), was used to demonstrate the intensity of intra/inter‐observer agreement.Results
The proposed projection was efficient in 79% of the angiograms, with agreement of 0.76 (0.6–0.9; P ≤ 0.001). The origins and the proximal segments of: the anterior descending coronary artery were exposed in 89% of the angiograms, agreement of 0.86 (0.7–1.0; P ≤ 0.001); the circumflex artery were exposed in 83% of the angiograms, with agreement of 0.72 (0.5–1.0; P ≤ 0.001); and the intermediate branch, when present, were exposed in 89% of the angiograms, agreement of 0.79 (0.6–1.0; P ≤ 0.001).Conclusion
The right lateral (90–120° RAO) with 30° cranial projection is effective, safe, and reproducible. In special situations where routine projections fail, this proposed projection can reveal important details of the anatomy of the bifurcation of the LMCA during conventional coronary angiography or be the working projection during coronary angioplasty. (J Interven Cardiol 2016;29:293–299)106.
Jo?o Alves de Araújo-Filho Arioldo Carvalho Vasconcelos-Jr Eduardo Martins de Sousa Colombina da Silveira Patrícia Tavares Pereira de Sousa Klaus Andrade Severo Ludmila Ferreira Vieira André Kipnis Ana Paula Junqueira-Kipnis 《The Brazilian journal of infectious diseases》2008,12(1):94-98
Multidrug-resistant tuberculosis (MDR-TB) is an emerging and worrisome health problem that threatens tuberculosis (TB) control worldwide. The clinical management of MDR-TB is a complex issue associated with the use of multiple drugs for a long period, usually accompanied by side effects and high costs. The objective of this work was to relate cases of MDR-TB occurring in Goiás, a central state of Brazil. We related five cases of MDR-TB, three women and two men. All were pulmonary cases. Three were in their second treatment and two in their first treatment. Surgical pulmonary resection was performed in one case. One death occurred. Lack of adherence, gastric intolerance to anti-TB drugs and poor clinical management were the main aspects related to the emergent resistance. A revision of the main clinical aspects of this disease was performed. 相似文献
107.
Ismael Nilo Lino de Queiroz Ana Luíza Gomes Quinderé José Ariévilo Gurgel Rodrigues Edfranck de Sousa Oliveira Vanderlei Natássia Albuquerque Ribeiro Renata Line da Conceição Rivanor Kátia Alves Ribeiro Chistiane Oliveira Coura Karuza Maria Alves Pereira Hellíada Vasconcelos Chaves Mirna Marques Bezerra Ianna Wivianne Fernandes de Araújo Norma Maria Barros Benevides 《Inflammation research》2015,64(12):971-982
108.
Cleverson Alves da Silva Moura Guilherme Kretzmann Belmonte Pulikanti Guruprasad Reddy Kenneth E. Gonslaves Daniel Eduardo Weibel 《RSC advances》2018,8(20):10930
A detailed investigation to understand the mechanism of the resist action at a fundamental level is essential for future Extreme Ultraviolet Lithography (EUVL) resists. The photodynamics study of a newly developed hybrid nonchemically amplified 2.15%-MAPDSA–MAPDST resist using synchrotron radiation excitation at 103.5 eV (12 nm) is presented. Antimony was incorporated in the resist as a heavy metal absorption center in the form of antimonate (2.15%). The results showed the fast decomposition rate of the radiation sensitive sulfonium triflate. HR-XPS and sulfur L-NEXAFS spectra of the copolymer films revealed that after irradiation the Ar–S+–(CH3)2 sulfonium group bonded to the phenyl ring resisted the EUV excitation. Those results confirmed the polarity switching mechanism from hydrophilic sulfonium triflates to hydrophobic aromatic sulfides obtained in previous results. The inorganic component SbF6− included in the resist formulations as an EUV absorption enhancer was particularly illustrative of the photofragmentation process. F 1s and O 1s HR-XPS spectra showed that fluorine remains linked to the antimony, even after 15 min of irradiation. A change of the antimony oxidation state was also observed with an increase in irradiation time. The presence of the heavy metal may control the high energy deposited on the resist which finally led to very well resolved 20 nm isolated line patterns by EUVL. The 10 times improved sensitivity compared with previous poly-MAPDST resists studied in the past showed the potential of this class of hybrid resists for next generation semiconductor industry applications.Understanding the EUV photofragmentation mechanism in a highly sensitive hybrid n-CAR containing SbF6− as an absorption enhancer. 相似文献
109.
Ana Carolina G. Zanetti Tais Milena Pantaleão de Souza Larissa de Souza Tressoldi João Mazzoncini de Azevedo-Marques Gabriel Elias Corrêa-Oliveira Amanda Heloisa Santana da Silva Isabela dos Santos Martin Kelly Graziani Giacchero Vedana Lucilene Cardoso Sueli Aparecida Frari Galera Edilaine Cristina da Silva Gherardi-Donato 《Archives of Psychiatric Nursing》2018,32(3):390-395
BACKGROUND
Evidence suggests that expressed emotion (EE) and family burden (FB) are phenomena that interact, but there is a lack of studies that analyze this association in patients in first-episode psychosis.AIM
This study evaluated the relationship between EE and FB in relatives of patients in first-episode psychosis.METHOD
A convenience sample of 71 family members of patients being assisted in an outpatient care unit participated in the study. We used a form with sociodemographic and clinical variables of family members and patients, the Family Questionnaire-Brazilian Portuguese Version and the Brazilian version of the Burden Interview. The data were obtained via semi-structured interviews. Statistical analyses included Fisher's exact tests, Mann Whitney tests, Spearman correlations, and Student's t-tests.RESULTS
Our results showed high levels of EE and its component emotional over-involvement (EOI) among relatives, and a strong correlation between critical comments (CC) and EOI and FB measurements. In addition, family members with elevated EE levels showed higher means for FB and this difference was significant.CONCLUSIONS
Mental health nurses are expected to consider these concepts for proposing nursing interventions to first-episode psychosis patients and their relatives. 相似文献110.
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