全文获取类型
收费全文 | 615篇 |
免费 | 52篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 18篇 |
妇产科学 | 12篇 |
基础医学 | 79篇 |
口腔科学 | 9篇 |
临床医学 | 113篇 |
内科学 | 113篇 |
皮肤病学 | 11篇 |
神经病学 | 80篇 |
特种医学 | 17篇 |
外科学 | 61篇 |
综合类 | 7篇 |
一般理论 | 2篇 |
预防医学 | 62篇 |
眼科学 | 1篇 |
药学 | 52篇 |
中国医学 | 1篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 23篇 |
2020年 | 13篇 |
2019年 | 20篇 |
2018年 | 30篇 |
2017年 | 17篇 |
2016年 | 23篇 |
2015年 | 23篇 |
2014年 | 34篇 |
2013年 | 40篇 |
2012年 | 53篇 |
2011年 | 50篇 |
2010年 | 24篇 |
2009年 | 24篇 |
2008年 | 41篇 |
2007年 | 36篇 |
2006年 | 43篇 |
2005年 | 38篇 |
2004年 | 33篇 |
2003年 | 15篇 |
2002年 | 17篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 7篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 4篇 |
1966年 | 1篇 |
1965年 | 2篇 |
1959年 | 1篇 |
1910年 | 1篇 |
1903年 | 1篇 |
1902年 | 1篇 |
排序方式: 共有668条查询结果,搜索用时 15 毫秒
601.
Walker LC Krause L;kConFab Investigators Spurdle AB Waddell N 《Breast cancer research and treatment》2012,134(3):1005-1011
A characteristic of sporadic and familial breast tumours is genomic instability, resulting from either inherited mutations in genes that control genome integrity or mutations that are acquired in somatic cells during development. It is well established that abnormal chromosome number and structural changes to chromosomes play an important role in the cause and progression of breast cancer. Familial BRCA1 breast tumours are characterised by basal-like phenotype and high-histological grade which are typically associated with increased genomic instability. Consistent with previous studies, the genomes with the greatest number of base pairs covered by copy number change were typically found in basal-like and/or high-histological grade breast tumours within our cohort. Moreover, we show that luminal A tumours that are high grade had significantly less copy number variant (CNV) coverage than the more clinically aggressive high-grade luminal B tumours, suggesting that chromosomal instability rather than cellular differentiation contributes to the aggressive nature of luminal B tumours. It has previously been proposed that germline CNVs may contribute to somatically acquired chromosome changes in the tumour, but this is the first study to address this idea in breast cancer. By comparing germline CNVs and tumour-specific CNVs in matched breast tumour and normal tissue using data from the Illumina Human CNV370 duo beadarray, we provide evidence that germline CNVs do not tend to act as a foundation on which larger chromosome copy number aberrations develop in tumour cells. Further studies are required with increased sequence resolution that will detect smaller CNVs and define CNV breakpoints to comprehensively assess the relationship between inherited genomic variation and genome evolution in breast cancer. 相似文献
602.
Ettrup A Hansen M Santini MA Paine J Gillings N Palner M Lehel S Herth MM Madsen J Kristensen J Begtrup M Knudsen GM 《European journal of nuclear medicine and molecular imaging》2011,38(4):681-693
Purpose
Positron emission tomography (PET) imaging of serotonin 2A (5-HT2A) receptors with agonist tracers holds promise for the selective labelling of 5-HT2A receptors in their high-affinity state. We have previously validated [11C]Cimbi-5 and found that it is a 5-HT2A receptor agonist PET tracer. In an attempt to further optimize the target-to-background binding ratio, we modified the chemical structure of the phenethylamine backbone and carbon-11 labelling site of [11C]Cimbi-5 in different ways. Here, we present the in vivo validation of nine novel 5-HT2A receptor agonist PET tracers in the pig brain.Methods
Each radiotracer was injected intravenously into anaesthetized Danish Landrace pigs, and the pigs were subsequently scanned for 90?min in a high-resolution research tomography scanner. To evaluate 5-HT2A receptor binding, cortical nondisplaceable binding potentials (BPND) were calculated using the simplified reference tissue model with the cerebellum as a reference region.Results
After intravenous injection, all compounds entered the brain and distributed preferentially into the cortical areas, in accordance with the known 5-HT2A receptor distribution. The largest target-to-background binding ratio was found for [11C]Cimbi-36 which also had a high brain uptake compared to its analogues. The cortical binding of [11C]Cimbi-36 was decreased by pretreatment with ketanserin, supporting 5-HT2A receptor selectivity in vivo. [11C]Cimbi-82 and [11C]Cimbi-21 showed lower cortical BPND, while [11C]Cimbi-27, [11C]Cimbi-29, [11C]Cimbi-31 and [11C]Cimbi-88 gave rise to cortical BPND similar to that of [11C]Cimbi-5.Conclusion
[11C]Cimbi-36 is currently the most promising candidate for investigation of 5-HT2A receptor agonist binding in the living human brain with PET. 相似文献603.
604.
605.
Aquaporin-9 (AQP-9) regulates tissue hydration by promoting transmembrane exchanges of both water and solutes, such as lactate. The latter is a key metabolite of primary spermatocytes and of maturing haploid germ cells (h-GCs). The present investigation was aimed at immunolocalising human AQP-9 in both normal and varicocele testes. Histology and immmunocytochemistry were investigated in archival biopsies from 20 varicocele testes and in eight unaffected ones. AQP-9 immunostaining was performed using a rabbit antibody, and either focal or diffuse cell membrane labelling was recorded. Varicocele testes showed disarranged tubular compartments, with sloughing h-GCs, tissue hyperhydration, spermiogenesis failure and fibrosis. AQP-9 immunohistology of the control testes showed a diffuse cell membrane staining of the primary spermatocytes and h-GCs, without any positive reaction of spermatogonia and Sertoli cells. AQP-9 cell expression in the varicocele testes was focal or lacking in both adluminal and sloughing GCs. AQP-9 expression occurs in normal human testis, at cell membrane of primary spermatocytes and h-GCs, suggesting a possible role of AQP-9 in the water and lactate transport from Sertoli cells to GCs. AQP-9 is focal or lacking in adolescent varicocele testes, and this suggests AQP-9 to be downregulated in such testicular disorder, leading to lactate deprivation with subsequent hypospermatogenesis. 相似文献
606.
607.
van der Helm LH Alhan C Wijermans PW van Marwijk Kooy M Schaafsma R Biemond BJ Beeker A Hoogendoorn M van Rees BP de Weerdt O Wegman J Libourel WJ Luykx-de Bakker SA Minnema MC Brouwer RE Croon-de Boer F Eefting M Jie KS van de Loosdrecht AA Koedam J Veeger NJ Vellenga E Huls G 《British journal of haematology》2011,155(5):599-606
The efficacy of azacitidine in the treatment of high‐risk myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML) and acute myeloid leukaemia (AML) (20–30% blasts) has been demonstrated. To investigate the efficacy of azacitidine in daily clinical practice and to identify predictors for response, we analysed a cohort of 90 MDS, CMML and AML patients who have been treated in a Dutch compassionate named patient programme. Patients received azacitidine for a median of five cycles (range 1–19). The overall response rate (complete/partial/haematological improvement) was 57% in low risk MDS, 53% in high risk MDS, 50% in CMML, and 39% in AML patients. Median overall survival (OS) was 13·0 (9·8–16·2) months. Multivariate analysis confirmed circulating blasts [Hazard Ratio (HR) 0·48, 95% confidence interval (CI) 0·24–0·99; P = 0·05] and poor risk cytogenetics (HR 0·45, 95% CI 0·22–0·91; P = 0·03) as independent predictors for OS. Interestingly, this analysis also identified platelet doubling after the first cycle of azacitidine as a simple and independent positive predictor for OS (HR 5·4, 95% CI 0·73–39·9; P = 0·10). In conclusion, routine administration of azacitidine to patients with variable risk groups of MDS, CMML and AML is feasible, and subgroups with distinct efficacy of azacitidine treatment can be identified. 相似文献
608.
Eimear Muir-Cochrane BSc RN RPN Grad Dip Adult Ed MN 《Journal of advanced nursing》1996,23(3):555-563
Seclusion continues to be used in the care of acutely disturbed psychiatric patients despite often emotionally charged debate about its appropriateness within mental health services Powerful legal and moral arguments about the use of seclusion emphasize an urgent need to critically examine its role in the care of mentally ill people This paper examines the use of seclusion on closed psychiatric wards in the management of acutely disturbed patients Seven psychiatric nurses working in two closed wards in an Australian teaching hospital were interviewed in relation to their perceptions of the role of seclusion Data were analysed using grounded theory methodology revealing the core conceptual category 'controlling' and two sub-categories 'watching out for' and 'watching over' Seclusion was found to be used as an adjunctive treatment in the care of individuals considered to be 'out of control' Clinicians expressed comfort with the use of seclusion, citing a strict protocol that provided parameters for its use Whilst expert therapeutic interventions were described by clinicians, they are contextuahzed within a framework of power and control—a framework that stands in stark contrast to contemporary philosophies of nursing care, providing impetus for a reconsideration of the use of constraining practices in the care of mentally ill people 相似文献
609.
610.