全文获取类型
收费全文 | 475篇 |
免费 | 52篇 |
国内免费 | 20篇 |
专业分类
547篇 |
出版年
2024年 | 3篇 |
2023年 | 10篇 |
2022年 | 20篇 |
2021年 | 33篇 |
2020年 | 27篇 |
2019年 | 25篇 |
2018年 | 27篇 |
2017年 | 19篇 |
2016年 | 20篇 |
2015年 | 22篇 |
2014年 | 32篇 |
2013年 | 40篇 |
2012年 | 31篇 |
2011年 | 32篇 |
2010年 | 25篇 |
2009年 | 24篇 |
2008年 | 30篇 |
2007年 | 20篇 |
2006年 | 16篇 |
2005年 | 15篇 |
2004年 | 11篇 |
2003年 | 15篇 |
2002年 | 7篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有547条查询结果,搜索用时 15 毫秒
11.
Rita Flix Soares Ana Rita Garcia Ana Raquel Monteiro Filipa Macedo Tatiana Cunha Pereira Joana Cunha Carvalho Antnio Pêgo Mnica Mariano Pedro Madeira Sara Pvoa Sofia Broco Teresa Carvalho Isabel Pazos Gabriela Sousa 《Reports of Practical Oncology and Radiotherapy》2021,26(4):563
BackgroundTriple negative breast cancer (TNBC) has the worst prognosis amongst all subtypes. Studies have shown that the achievement of pathologic complete response in the breast and axilla correlates with improved survival. The aim of this study was to identify clinical or pathological features of real-life TNBC patients with a higher risk of early relapse.Materials and methodsSingle-centre retrospective analysis of 127 women with TNBC, stage II–III, submitted to neoadjuvant treatment and surgery between January 2016 and 2020. Multivariate Cox regression analysis for disease free survival (DFS) at 2 years was performed and statistically significant variables were computed into a prognostic model for early relapse.ResultsAfter 29 months of median follow-up, 105 patients (82.7%) were alive and, in total, 38 patients (29.9%) experienced recurrence. The 2-year DFS was 73% (95% CI: 21.3–22.7). In multivariate analysis, being submitted to neoadjuvant radiotherapy [HR 2.8 (95% CI: 1.2–6.4), p = 0.017] and not achieving pathologic complete response [HR 0.3 (95% CI: 0.1–1.7), p = 0.011] were associated with higher risk of recurrence. In our prognostic model, the presence of at least one of these variables defined a subgroup of patients with a worse 2-year DFS than those without these features (59% vs. 90%, p < 0.001, respectively).ConclusionsIn this real-life non-metastatic TNBC cohort, neoadjuvant radiotherapy (performed due to insufficient clinical response to neoadjuvant chemotherapy or significant toxicity) impacted as an independent prognostic factor for relapse along with the absence of pathologic complete response identifying a subgroup of higher risk patients for early relapse that might merit a closer follow-up. 相似文献
12.
Font-Montgomery E Weaver DD Walsh L Christensen C Thurston VC 《Birth defects research. Part A, Clinical and molecular teratology》2004,70(6):408-415
BACKGROUND: Fluorescent subtelomeric probes for the 41 different subtelomeric regions (the p arms of the acrocentric chromosomes were excluded) have been developed over the last 10 years. These probes can detect deletions, duplications, and translocations in the gene-rich subtelomeric regions of human chromosomes, regions where crossing over frequently occurs and where a high number of abnormalities have been found. Recently, commercially produced probes have become available, which has led to the detection of subtelomeric abnormalities in 7.4% of patients with moderate to severe mental retardation (Knight et al., 1999). CASES: We evaluated 43 dysmorphic children with developmental delay and/or mental retardation of unknown etiology and/or autism who were previously assessed for chromosome abnormalities, metabolic disorders, or recognizable dysmorphic syndromes, all of which were ruled out. Of the 43 children tested, 6 (14%) were found to have subtelomeric aberrations. CONCLUSIONS: We recommend that patients with dysmorphic features and mental retardation of unknown etiology who also have a normal standard chromosome analysis should have subtelomeric FISH testing performed earlier in their clinical workup. 相似文献
13.
Sonia Johnson Christian DaltonLocke John Baker Charlotte Hanlon Tatiana Taylor Salisbury Matt Fossey Karen Newbigging Sarah E. Carr Jennifer Hensel Giuseppe Carr Urs Hepp Constanza Caneo Justin J. Needle Brynmor LloydEvans 《World psychiatry》2022,21(2):220
Acute services for mental health crises are very important to service users and their supporters, and consume a substantial share of mental health resources in many countries. However, acute care is often unpopular and sometimes coercive, and the evidence on which models are best for patient experience and outcomes remains surprisingly limited, in part reflecting challenges in conducting studies with people in crisis. Evidence on best approaches to initial assessment and immediate management is particularly lacking, but some innovative models involving extended assessment, brief interventions, and diversifying settings and strategies for providing support are potentially helpful. Acute wards continue to be central in the intensive treatment phase following a crisis, but new approaches need to be developed, evaluated and implemented to reducing coercion, addressing trauma, diversifying treatments and the inpatient workforce, and making decision‐making and care collaborative. Intensive home treatment services, acute day units, and community crisis services have supporting evidence in diverting some service users from hospital admission: a greater understanding of how best to implement them in a wide range of contexts and what works best for which service users would be valuable. Approaches to crisis management in the voluntary sector are more flexible and informal: such services have potential to complement and provide valuable learning for statutory sector services, especially for groups who tend to be underserved or disengaged. Such approaches often involve staff with personal experience of mental health crises, who have important potential roles in improving quality of acute care across sectors. Large gaps exist in many low‐ and middle‐income countries, fuelled by poor access to quality mental health care. Responses need to build on a foundation of existing community responses and contextually relevant evidence. The necessity of moving outside formal systems in low‐resource settings may lead to wider learning from locally embedded strategies. 相似文献
14.
Population‐based analysis of health care contacts among suicide decedents: identifying opportunities for more targeted suicide prevention strategies 下载免费PDF全文
Ayal Schaffer Mark Sinyor Paul Kurdyak Simone Vigod Jitender Sareen Catherine Reis Diane Green James Bolton Anne Rhodes Sophie Grigoriadis John Cairney Amy Cheung 《World psychiatry》2016,15(2):135-145
The objective of this study was to detail the nature and correlates of mental health and non‐mental health care contacts prior to suicide death. We conducted a systematic extraction of data from records at the Office of the Chief Coroner of Ontario of each person who died by suicide in the city of Toronto from 1998 to 2011. Data on 2,835 suicide deaths were linked with provincial health administrative data to identify health care contacts during the 12 months prior to suicide. Sub‐populations of suicide decedents based on the presence and type of mental health care contact were described and compared across socio‐demographic, clinical and suicide‐specific variables. Time periods from last mental health contact to date of death were calculated and a Cox proportional hazards model examined covariates. Among suicide decedents, 91.7% had some type of past‐year health care contact prior to death, 66.4% had a mental health care contact, and 25.3% had only non‐mental health contacts. The most common type of mental health contact was an outpatient primary care visit (54.0%), followed by an outpatient psychiatric visit (39.8%), an emergency department visit (31.1%), and a psychiatric hospitalization (21.0%). The median time from last mental health contact to death was 18 days (interquartile range 5‐63). Mental health contact was significantly associated with female gender, age 25‐64, absence of a psychosocial stressor, diagnosis of schizophrenia or bipolar disorder, past suicide attempt, self‐poisoning method and absence of a suicide note. Significant differences between sub‐populations of suicide decedents based on the presence and nature of their health care contacts suggest the need for targeting of community and clinical‐based suicide prevention strategies. The predominance of ambulatory mental health care contacts, often close to the time of death, reinforce the importance of concentrating efforts on embedding risk assessment and care pathways into all routine primary and specialty clinical care, and not only acute care settings. 相似文献
15.
This paper aims to give an overview of the key issues facing those who are in a position to influence the planning and provision of mental health systems, and who need to address questions of which staff, services and sectors to invest in, and for which patients. The paper considers in turn: a) definitions of community mental health care; b) a conceptual framework to use when evaluating the need for hospital and community mental health care; c) the potential for wider platforms, outside the health service, for mental health improvement, including schools and the workplace; d) data on how far community mental health services have been developed across different regions of the world; e) the need to develop in more detail models of community mental health services for low‐ and middle‐income countries which are directly based upon evidence for those countries; f) how to incorporate mental health practice within integrated models to identify and treat people with comorbid long‐term conditions; g) possible adverse effects of deinstitutionalization. We then present a series of ten recommendations for the future strengthening of health systems to support and treat people with mental illness. 相似文献
16.
Does the primary visual cortex mediate consciousness for higher-level stages of information processing by providing an outlet for mental imagery? Evidence based on neural electrical activity is inconclusive as reflected in the “imagery debate” in cognitive science. Neural information and activity, however, also depend on regulated biophoton (optical) signaling. During encoding and retrieval of visual information, regulated electrical (redox) signals of neurons are converted into synchronized biophoton signals by bioluminescent radical processes. That is, visual information may be represented by regulated biophotons of mitochondrial networks in retinotopically organized cytochrome oxidase-rich neural networks within early visual areas. Therefore, we hypothesize that regulated biophotons can generate intrinsic optical representations in the primary visual cortex and then propagate variably degraded versions along cytochrome oxidase pathways during both perception and imagery. Testing this hypothesis requires to establish a methodology for measurement of in vivo and/or in vitro increases of biophoton emission in humans' brain during phosphene inductions by transcranial magnetic stimulation and to compare the decrease in phosphene thresholds during transcranial magnetic stimulation and imagery. Our hypothesis provides a molecular mechanism for the visual buffer and for imagery as the prevalent communication mode (through optical signaling) within the brain. If confirmed empirically, this hypothesis could resolve the imagery debate and the underlying issue of continuity between perception and abstract thought. 相似文献
17.
18.
基于潜意识理论的青少年网络成瘾研究 总被引:1,自引:0,他引:1
李春明 《现代生物医学进展》2007,7(10):1560-1562
本文综述了青少年网络成瘾的预防和戒除方法,坚持了"习惯说",保留了对"疾病说"的看法。基于潜意识理论,将网络成瘾视为心理亚健康状态,分析了青少年网络成瘾的发生机理、提出了其预防和戒除原则。青少年网络成瘾的成因是心理上的缺失感,与青少年自我防护意识差、自我控制能力小、心理弹性弱,以及潜意识具有反复影响才可改变的特点有关。戒除网络成瘾的原则是淡化评判试测的标准、分散注意力、培养成就感、增强自信心、坚持以心治心等。 相似文献
19.
F W Jennings D D Whitelaw P H Holmes H G Chizyuka G M Urquhart 《International journal for parasitology》1979,9(4):381-384
During the aparasitaemic period following chemotherapy of all three strains of T. brucei infections in mice, successful transmission as shown by subsequent parasitaemia, was regularly achieved following the inoculation of homogenates of brain tissue into recipient mice. Transmission with blood obtained at the same time was consistently negative and in the case of T. brucei TREU 667, homogenates of other organs were non-infective. The implications of this central nervous system involvement are discussed with particular reference to its use as a model for relapsing infections after therapy in man. 相似文献
20.
Szukała K Sowińska A Wierzbicka M Biczysko W Szyfter W Szyfter K 《Mutation research》2006,600(1-2):67-76
BACKGROUND: Patients, who had an upper aerodigestive tract malignancy, have a high incidence of succeeding tumor development. This has been attributed to the role of "field cancerization" in carcinogenesis. The aim of this study was analysis of loss of heterozygosity (LOH) in the regions frequently lost during the course of head and neck squamous cell carcinomas (HNSCC), especially at early stages, which could answer the clinicians' question, if LOH analysis has any "predictive" value in relation to tumor occurrence. MATERIAL AND METHODS: Sixty-five larynx cancer patients were examined for loss of heterozygosity on 3p, 7q, 8p, 9p and 18q chromosomal arms with the use of 12 microsatellite markers. The material from a single patient consisted of blood, tumor, safe margin and one or two clinically unchanged mucosal samples. During follow up, the material from brush specimens (14 patients) as well as laryngeal swabs (4 patients) was also examined. RESULTS: The highest frequency of LOH was detected for marker D3S1234 in tumor tissues (29%). Analysis of margin samples (b) revealed low LOH frequencies (2-5%) and complete retention of heterozygosity for markers: D3S1234, D7S486, D8S261, D8S264, D9S171 and D18S46. Similarly, for normal appearing mucosa from upper part of larynx (c) frequencies of LOH were low (2-6%), with the complete retention of heterozygosity for markers: D3S1284, D3S1304, D3S1234, D8S264 and D9S1870. We did not detect any LOH in the material of normal appearing mucosa from tracheostoma region (d). During follow up, LOH was detected for eight markers, with the highest incidence for markers D18S46 (six cases), D7S486 (four cases) and D3S1300 (three cases). CONCLUSIONS: The data, obtained during this investigation, did not reveal the predictive value of LOH with respect to local relapse occurrence in laryngeal cancer patients. However, time of follow up did not reach 5 years, so that further clinical monitoring should be conducted. 相似文献