全文获取类型
收费全文 | 550篇 |
免费 | 25篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 43篇 |
妇产科学 | 3篇 |
基础医学 | 67篇 |
口腔科学 | 2篇 |
临床医学 | 45篇 |
内科学 | 161篇 |
皮肤病学 | 3篇 |
神经病学 | 43篇 |
特种医学 | 8篇 |
外科学 | 49篇 |
综合类 | 7篇 |
预防医学 | 40篇 |
眼科学 | 13篇 |
药学 | 26篇 |
中国医学 | 3篇 |
肿瘤学 | 58篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 12篇 |
2021年 | 28篇 |
2020年 | 9篇 |
2019年 | 17篇 |
2018年 | 29篇 |
2017年 | 14篇 |
2016年 | 21篇 |
2015年 | 11篇 |
2014年 | 11篇 |
2013年 | 24篇 |
2012年 | 32篇 |
2011年 | 46篇 |
2010年 | 21篇 |
2009年 | 17篇 |
2008年 | 33篇 |
2007年 | 36篇 |
2006年 | 32篇 |
2005年 | 33篇 |
2004年 | 24篇 |
2003年 | 15篇 |
2002年 | 17篇 |
2001年 | 18篇 |
2000年 | 18篇 |
1999年 | 11篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有575条查询结果,搜索用时 0 毫秒
81.
Ki67 Changes Identify Worse Outcomes in Residual Breast Cancer Tumors After Neoadjuvant Chemotherapy 下载免费PDF全文
82.
Cárdaba B Ezendam J Gallardo S del Pozo V Izquierdo M Martín C Cortegano I Aceituno E Rojo M Arrieta I Palomino P Posada M Lahoz C 《Tissue antigens》2000,55(2):110-117
Toxic oil syndrome (TOS) was an epidemic which broke out in Spain in 1981, caused by the ingestion of rapeseed oil denatured with 2% aniline and sold illegally as edible oil. More than 20,000 people were affected and mortality rate was 8.4%. Genetic susceptibility appears to be involved in the pathology of this disease. Several reports have described association between the chronic stage of the disease and DR-DQ antigens (DR3, DR4, DR2 and DQ8). In the present work, we have reassessed the HLA class II antigens in a well-designed case-control study. Triplets of subjects (n=265) composed by chronic patients (n=117), non-affected family members (n=71) and non-related controls (n=77) were studied. Also, HLA class II antigens were analyzed in patients who had died from TOS (n= 34) and in TOS control patients who died from other non-TOS related causes (n=13). Regarding surviving patients no significant association was found between HLA and disease. In contrast, an increase in phenotypic frequency of DR2 antigen, was found in patients who had died from TOS (73.5%) compared with the whole study group: TOS-affected alive patients (25.6%, corrected P<0.001), non-affected family members (28.5%, corrected P<0.001), non-related controls (23.9%, corrected P<0.001) and dead controls (38.4%, P=0.03). 相似文献
83.
Peru is moving toward a universal health insurance system, and it is facing important challenges in the provision of public health services. As more citizens gain access to health insurance, the flow of patients exceeds the capacity of public hospitals to provide care with quality. In this study we explore the relationship between technical efficiency and patient safety events in neonatal care units of Peru’s public hospitals. We use Data Envelope Analysis (DEA) with output congestion to assess the association between technical efficiency and patient safety events. We study 35 neonatal care units of public hospitals in Peru’s Social Security Health System, and identify two undesirable (risk-adjusted) safety outcomes: neonatal mortality and near-miss neonatal mortality. We found that for about half of hospital’s neonatal care units, technical efficiency is affected by output congestion. For those hospitals, patient safety is being compromised by receiving too many patients. Our results are consistent with public reports indicating that hospitals in the Peru’s Social Security Health System are overcrowded, affecting efficiency and jeopardizing quality of care. We found that most congested hospitals are located in the capital city and suburban areas, and are more likely to be hospitals with the lowest and the highest level of care. Our results call for improvements in the patient referral system and capacity expansion. 相似文献
84.
85.
Arrieta J Arrieta Lezama J Gutiérrez Avila G Gutiérrez Avila G Moreno Alía I Moreno Alía I Sierra Yébenes T Sierra Yébenes T Estébanez C Estébanez C Olmos Linares AM Olmos Linares AM González R González R Fernández Renedo C Fernández Renedo C Arias M Arias M Cotorruelo J Cotorruelo J de Francisco AL de Francisco AL Zurriaga O Zurriaga O García Blasco MJ García Blasco MJ García Bazaga Mde L García Bazaga Mde L Ramos Aceitero JM Ramos Aceitero JM Gil Paraíso A Gil Paraíso A Sánchez Casajús A 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2008,28(2):151-158
In 2005, renal replace treatment (dialysis and transplant) was necessary for about 40,000 people, without being known the number accurate and either their basic characteristics, such as: time in treatment, modality or treatment changes. The presented data cover the 76% of the Spanish population and are the result of the cooperation among technicians of registries, nephrologists and transplant coordinations. 4,125 people started RRT in 2005, the total estimated acceptance rate for renal replacement therapy in adults in Spain was 126 pmp and regarding other European countries it locates us in an intermediate area. The incidence rate seems to keep stable in the last years although there were some differences among communities (from 104 pmp in Castile and Leon to 186 pmp in Canary Islands). Diabetes Mellitus is the most diagnosed cause of renal failure in 2005, more than 20% of patients, followed by vascular diseases. The estimated prevalence of renal replacement therapy in Spain at the end of 2005 was 903 pmp, with important variations among communities (from 806 pmp in Cantabria to 1056 pmp in Valencia Region). The 47% of prevalent RRT patients had a functioning transplant. Mortality on haemodialysis and peritoneal dialysis was 13.7% and 10.8% respectively. Mortality on transplant was 1.3%, one of the lowest values registered so far. Mortality on renal replacement therapy was around 5% among patients from 45 to 64 years, 11% between 65 and 74 years and 19% among the patients older than 75 years. 相似文献
86.
Reyes-Trejo B Sánchez-Mendoza ME Becerra-García AA Cedillo-Portugal E Castillo-Henkel C Arrieta J 《The Journal of pharmacy and pharmacology》2008,60(7):931-936
Croton reflexifolius H. B. K (Euphorbiaceae) is a very common medicinal plant in the Huastecan region of Mexico that, according to local folk medicine, is considered useful in the treatment of gastritis and gastric ulcer. We have aimed to test the validity of this practice by using the experimental model of an ethanol-induced gastric ulcer in male Wistar rats. The results showed that C. reflexifolius had gastroprotector activity, that the hexane extract had the highest protective activity (64.38+/-7.72%), and that polyalthic acid isolated from this extract was the main active gastroprotector agent. Rats treated orally with polyalthic acid showed a gastroprotective effect similar to that elicited by carbenoxolone. As with carbenoxolone, the effect elicited by polyalthic acid was attenuated by pretreatment with either N(G)-nitro-L-arginine methyl ester (70 mgkg(-1), i.p.), a nitric oxide (NO) synthase inhibitor, or N-ethylmaleimide (10 mgkg(-1), s.c.), a blocker of sulfhydryl groups. This suggested that the gastroprotective mechanism of this diterpenoid involved the participation of both NO and endogenous sulfhydryl groups. Contrary to carbenoxolone, the gastroprotective effect of polyalthic acid was not affected by the inhibition of prostaglandin synthesis with indometacin (10 mgkg(-1), s. c.). In conclusion, Croton reflexifolius contains compounds with gastroprotector activity. Polyalthic acid, which was isolated from this plant, was the main compound with gastroprotector activity, having effectiveness similar to that found with the use of carbenoxolone. Whereas NO and sulfhydryl groups were involved in the mechanisms of gastroprotective action of polyalthic acid, prostaglandins were not. 相似文献
87.
88.
89.
Ivan Cordon María Jesús Nicolás Sandra Arrieta Manuel Alegre Julio Artieda Miguel Valencia 《Brain stimulation》2018,11(1):231-238
Background
High-frequency deep brain stimulation (DBS) has become a widespread therapy used in the treatment of Parkinson's Disease (PD) and other diseases. Although it has proved beneficial, much recent attention has been centered around the potential of new closed-loop DBS implementations.Objective
Here we present a new closed-loop DBS scheme based on the phase of the theta activity recorded from the motor cortex. By testing the implementation on freely moving 6-OHDA lesioned and control rats, we assessed the behavioral and neurophysiologic effects of this implementation and compared it against the classical high-frequency DBS.Results
Results show that both stimulation modalities produce significant and opposite changes on the movement and neurophysiological activity. Close-loop stimulation, far from improving the animals' behavior, exert contrary effects to those of high-frequency DBS which reverts the parkinsonian symptoms. Motor improvement during open-loop, high-frequency DBS was accompanied by a reduction in the amount of cortical beta oscillations while akinetic and disturbed behavior during close-loop stimulation coincided with an increase in the amplitude of beta activity.Conclusion
Cortical-phase-dependent close-loop stimulation of the STN exerts significant behavioral and oscillatory changes in the rat model of PD. Open-loop and close-loop stimulation outcomes differed dramatically, thus suggesting that the scheme of stimulation determines the output of the modulation even if the target structure is maintained. The current framework could be extended in future studies to identify the correct parameters that would provide a suitable control signal to the system. It may well be that with other stimulation parameters, this sort of DBS could be beneficial. 相似文献90.
Mathias Bruyand Marie-Anne Vandenhende Guillaume Marcel Estibaliz Lazaro Marie-Edith Lafon Michel Dupon François Dabis Stéphane Geffard Hervé Fleury Muriel Faure-Della Corte Fabrice Bonnet Rodolphe Thiebaut Isabelle Garrigue 《Journal of clinical virology》2011,50(2):177-180
BackgroundCMV reactivation, which enhances immune senescence, could be associated with a higher risk of cancer.ObjectivesWe compared the prevalence of positive CMV DNAemia in HIV-infected patients with and without cancer.Study designThis case–control study, nested in the ANRS-CO3 Aquitaine Cohort, included patients with a first diagnosis of cancer (2002–2007) as cases. Two controls were matched per case.Cancer risk was estimated using conditional logistic regression models, an Odds Ratio (OR) of 2 could be detected with 80% power. The variables considered were: ≥1 positive CMV DNAemia, CD4+ and CD8+ counts, HIV plasma load. Plasma CMV DNA was retrospectively quantified within the 3-year period preceding the endpoint.ResultsThe 143 cases (93 non-AIDS-related and 50 AIDS-related cancers) and 284 controls had a median age of 47 years (IQR: 41–56). At the time of diagnosis or censorship, for cases and controls, median values were respectively, for CD4+ count: 327 cells/mm3 (IQR: 164–514) and 416 (IQR: 275–582), and for HIV plasma load: 2.6 log10 copies/mL (IQR: 1.7–4.7) and 1.7 log10 copies/mL (IQR: 1.7–3.3). We performed 2056 CMV PCR; 14 cases (9.8% [95% CI: 4.9–14.7]) and 19 controls (6.7% [CI: 3.8–9.6]) presented ≥1 positive PCR. CMV DNAemia was not associated with the risk of cancer (unadjusted and adjusted p-values = 0.19 and 0.54, respectively). HIV load >500 copies/mL was independently associated with a higher risk of cancer (OR = 2.02; p = 0.002; 95% CI: 1.29–3.17).ConclusionThis large case–control study did not show any differential exposure to positive CMV plasma DNAemia between cancer cases and controls. 相似文献