全文获取类型
收费全文 | 2538篇 |
免费 | 179篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 65篇 |
妇产科学 | 49篇 |
基础医学 | 344篇 |
口腔科学 | 14篇 |
临床医学 | 247篇 |
内科学 | 708篇 |
皮肤病学 | 30篇 |
神经病学 | 301篇 |
特种医学 | 48篇 |
外科学 | 186篇 |
综合类 | 21篇 |
一般理论 | 3篇 |
预防医学 | 236篇 |
眼科学 | 16篇 |
药学 | 196篇 |
中国医学 | 13篇 |
肿瘤学 | 245篇 |
出版年
2024年 | 6篇 |
2023年 | 38篇 |
2022年 | 55篇 |
2021年 | 92篇 |
2020年 | 58篇 |
2019年 | 81篇 |
2018年 | 84篇 |
2017年 | 68篇 |
2016年 | 66篇 |
2015年 | 85篇 |
2014年 | 103篇 |
2013年 | 136篇 |
2012年 | 213篇 |
2011年 | 211篇 |
2010年 | 118篇 |
2009年 | 101篇 |
2008年 | 163篇 |
2007年 | 172篇 |
2006年 | 165篇 |
2005年 | 151篇 |
2004年 | 156篇 |
2003年 | 127篇 |
2002年 | 122篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 13篇 |
1998年 | 14篇 |
1997年 | 13篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1984年 | 3篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1972年 | 6篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1968年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有2727条查询结果,搜索用时 15 毫秒
961.
Nkiruka V. Arinze Sharon M. Karp Sabina B. Gesell 《Journal of immigrant and minority health / Center for Minority Public Health》2016,18(1):282-286
Excessive gestational weight gain (GWG) is associated with complications for both mother and child. Minority women are at increased risk for excessive GWG, yet are underrepresented in published weight control interventions. To inform future interventions, we examined the prevalence and accuracy of provider advice and its association with personal beliefs about necessary maternal weight gain among predominantly Latina pregnant women. Secondary analysis examining baseline data (N = 123) from a healthy lifestyle randomized controlled trial conducted in and urban area of the South East. Only 23.6 % of women reported being told how much weight to gain during pregnancy; although 58.6 % received advice that met Institute of Medicine recommendations. Concordance of mothers’ personal weight gain target with clinical recommendations varied by mothers’ pre-pregnancy weight status [χ (4) 2 = 9.781, p = 0.044]. Findings suggest the need for prenatal providers of low-income, minority women to engage patients in shaping healthy weight gain targets as a precursor to preventing excessive GWG and its complications. 相似文献
962.
A number of state Medicaid programs have recently proposed or implemented new or increased copayments for nonemergent emergency department (ED) visits. Evidence suggests that copayments generally reduce the level of healthcare utilization, although there is little specific evidence regarding the effectiveness of copayments in reducing nonurgent ED use among Medicaid enrollees or other low‐income populations. Encouraging efficient and appropriate use of healthcare services will be of particular importance for Medicaid programs as they expand under the Patient Protection and Affordable Care Act. This analysis uses national data from 2001 to 2009 to examine the effect of copayments on nonurgent ED utilization among nonelderly adult enrollees. We find that visits among Medicaid enrollees in state‐years where a copayment is in place are significantly less likely to be for nonurgent reasons. Our findings suggest that copayments may be an effective tool for reducing use of the ED for nonurgent care. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
963.
Kirwan JR Fries JF Hewlett SE Osborne RH Newman S Ciciriello S van de Laar MA Dures E Minnock P Heiberg T Sanderson TC Flurey CA Leong AL Montie P Richards P 《The Journal of rheumatology》2011,38(8):1711-1715
The workshop Choosing or Developing Instruments held at the Outcome Measures in Rheumatology (OMERACT) 10 meeting was designed to help participants think about the underlying methods of instrument development. Conference pre-reading material and 3 brief introductory presentations elaborated the issues, and participants broke into discussion groups before reconvening to share insights, engage in a more general discussion of the issues, and vote on recommendations. Tradeoffs between using current imperfect measures and the long and complex process of developing new instruments were considered, together with the need for rigor in patient-reported outcome (PRO) instrument development. The main considerations for PRO instrument development were listed and a research agenda for action produced. As part of the agenda for action, it is recommended that researchers and patient partners work together to tackle these issues, and that OMERACT bring forward proposals for acceptable instrument development protocols that would meet an enhanced "Truth" statement in the OMERACT Filter. 相似文献
964.
Allegra A Sant'antonio E Penna G Alonci A D'Angelo A Russo S Cannavò A Gerace D Musolino C 《European journal of haematology》2011,86(2):93-110
Despite advances in understanding the molecular pathogenesis of multiple myeloma and promising new therapies, almost all patients eventually relapse with resistant disease. There is therefore a strong rationale for combining novel therapies that target intrinsic molecular pathways mediating multiple myeloma cell resistance. One such protein family is the heat shock proteins (HSP), especially the HSP90 family. Heat shock protein inhibitors have been identified as promising cancer treatments as, while they only inhibit a single biologic function, the chaperone-protein association, their effect is widespread as it results in the destruction of numerous client proteins. This article reviews the preclinical and clinical data, which support the testing of HSP90 inhibitors as cancer drugs and update the reader on the current status of the ongoing clinical trials of HSP90 inhibitors in multiple myeloma. 相似文献
965.
Janciauskiene SM Bals R Koczulla R Vogelmeier C Köhnlein T Welte T 《Respiratory medicine》2011,105(8):1129-1139
α1-Antitrypsin (AAT) is the archetype member of the serine protease inhibitor (SERPIN) supergene family. The AAT deficiency is most often associated with the Z mutation, which results in abnormal Z AAT folding in the endoplasmic reticulum of hepatocytes during biogenesis. This causes intra-cellular retention of the AAT protein rather than efficient secretion with consequent deficiency of circulating AAT. The reduced serum levels of AAT contribute to the development of chronic obstructive pulmonary disease (COPD) and the accumulation of abnormally folded AAT protein increases risk for liver diseases. In this review we show that with the discovery of AAT deficiency in the early 60s as a genetically determined predisposition to the development of early-onset emphysema, intensive investigations of enzymatic mechanisms that produce lung destruction in COPD were pursued. To date, the role of AAT in other than lung and liver diseases has not been extensively examined. Current findings provide new evidence that, in addition to protease inhibition, AAT expresses anti-inflammatory, immunomodulatory and antimicrobial properties, and highlight the importance of this protein in health and diseases. In this review co-occurrence of several diseases with AAT deficiency is discussed. 相似文献
966.
967.
968.
969.
Shoshy Mizrahy Sabina Rebe Raz Martin HasgaardHong Liu Neta Soffer-Tsur Keren Cohen Ram Dvash Dalit Landsman-Milo Maria G.E.G. BremerS. Moein Moghimi Dan Peer 《Journal of controlled release》2011,156(2):231-238
Hyaluronan (HA), a naturally occurring glycosaminoglycan, exerts different biological functions depending on its molecular weight ranging from 4000-10M Da. While high Mw HA (HMw-HA) is considered as anti-inflammatory, low Mw HA (LMw-HA) has been reported to activate an innate immune response. In addition, opposing effects on cell proliferation mediated by the HA receptor CD44, have also been reported for high and low Mw HA. We have previously demonstrated that HMw-HA can be covalently attached to the surface of lipid nanoparticles (NPs), endowing the carriers with long circulation and active targeting towards HA-receptors (CD44 and CD168) highly expressed on tumors. Here we present a small library of HA-coated NPs distinguished only by the Mw of their surface anchored HA ranging from 6.4 kDa to 1500 kDa. All types of NPs exerted no effect on macrophages, T cells and ovarian cancer cells proliferation. In addition, no induction of cytokines or complement activation was observed. The affinity towards the CD44 receptor was found to be solely controlled by the Mw of the NPs surface-bound HA, from extremely low binding for LMw-HA to binding with high affinity for HMw-HA. These findings have major implications for the use of HA in nanomedicine as LMw-HA surface modified-NPs could be a viable option for the replacement of polyethylene glycol (PEG) when passive delivery is required, lacking adverse effects such as complement activation and cytokine induction, while HMw-HA-coated NPs could be used for active targeting to CD44 overexpressing tumors and aberrantly activated leukocytes in inflammation. 相似文献
970.
Maria Teresa Pellecchia MD PhD Paolo Barone MD PhD Caterina Vicidomini PhD Carmine Mollica MD PhD Elena Salvatore MD PhD Marta Ianniciello MD Raffaele Liuzzi PhD Katia Longo MD Marina Picillo MD Giuseppe De Michele MD Alessandro Filla MD Arturo Brunetti MD Marco Salvatore MD Sabina Pappatà MD 《Movement disorders》2011,26(7):1303-1309
Diffusion‐weighted imaging has been largely used to detect and quantify early degenerative changes in patients with multiple system atrophy, but progression of neurodegeneration has been poorly investigated. We performed a serial diffusion‐weighted imaging study in a population of multiple system atrophy patients and analyzed the evolution of diffusion properties in striatal and extrastriatal brain regions. Diffusion‐weighted imaging was obtained in 11 multiple system atrophy patients at baseline and after a follow‐up of 11.7 ± 1.2 months, and Trace (D) changes in different brain regions were correlated with disease duration and severity. A significant increase in Trace (D) was observed at follow‐up in the putamen (P < .001), pons (P = .003), cerebellar white matter (P = .03), thalamus (P = .013), and frontal white matter (P = .021). Both Unified Multiple System Atrophy Rating Scale Part II and Unified Parkinson's Disease Rating Scale Part III scores significantly increased at follow‐up (P = .003), but percent changes of Unified Parkinson's Disease Rating Scale Part III and Unified Multiple System Atrophy Rating Scale Part II did not correlate with percent changes of Trace (D) values in any brain region. This longitudinal study provides new insights into the progression of neurodegeneration in different brain regions in multiple system atrophy. Our results confirm that abnormal diffusivity in the putamen is sensitive to change over time in multiple system atrophy patients and show for the first time a progression of Trace (D) alterations in specific extrastriatal regions. Diffusivity changes in these regions may be useful for monitoring disease progression even after a short follow‐up period. © 2011 Movement Disorder Society 相似文献