全文获取类型
收费全文 | 74958篇 |
免费 | 5548篇 |
国内免费 | 162篇 |
专业分类
耳鼻咽喉 | 593篇 |
儿科学 | 2799篇 |
妇产科学 | 2476篇 |
基础医学 | 9145篇 |
口腔科学 | 1007篇 |
临床医学 | 13184篇 |
内科学 | 13385篇 |
皮肤病学 | 1112篇 |
神经病学 | 6917篇 |
特种医学 | 1376篇 |
外国民族医学 | 33篇 |
外科学 | 6391篇 |
综合类 | 969篇 |
一般理论 | 129篇 |
预防医学 | 10526篇 |
眼科学 | 852篇 |
药学 | 4204篇 |
1篇 | |
中国医学 | 103篇 |
肿瘤学 | 5466篇 |
出版年
2023年 | 420篇 |
2022年 | 544篇 |
2021年 | 1430篇 |
2020年 | 1043篇 |
2019年 | 1717篇 |
2018年 | 1919篇 |
2017年 | 1343篇 |
2016年 | 1567篇 |
2015年 | 1697篇 |
2014年 | 2260篇 |
2013年 | 3664篇 |
2012年 | 5185篇 |
2011年 | 5457篇 |
2010年 | 2943篇 |
2009年 | 2722篇 |
2008年 | 4897篇 |
2007年 | 5453篇 |
2006年 | 5287篇 |
2005年 | 5098篇 |
2004年 | 4921篇 |
2003年 | 4668篇 |
2002年 | 4405篇 |
2001年 | 600篇 |
2000年 | 454篇 |
1999年 | 603篇 |
1998年 | 992篇 |
1997年 | 758篇 |
1996年 | 683篇 |
1995年 | 592篇 |
1994年 | 567篇 |
1993年 | 560篇 |
1992年 | 386篇 |
1991年 | 334篇 |
1990年 | 312篇 |
1989年 | 278篇 |
1988年 | 268篇 |
1987年 | 258篇 |
1986年 | 243篇 |
1985年 | 285篇 |
1984年 | 295篇 |
1983年 | 304篇 |
1982年 | 382篇 |
1981年 | 361篇 |
1980年 | 304篇 |
1979年 | 174篇 |
1978年 | 163篇 |
1977年 | 175篇 |
1976年 | 160篇 |
1975年 | 135篇 |
1974年 | 123篇 |
排序方式: 共有10000条查询结果,搜索用时 835 毫秒
991.
Maryam Esmaeili Martin Berry Ann Logan Zubair Ahmed 《中国神经再生研究》2014,9(18):1653-1656
The scarring response after a penetrant central nervous system injury results from the interaction between invading leptominingeal/pericyte-derived fibroblasts and endogenous reactive astrocytes about the wound margin. Extracellular matrix and scar-derived axon growth inhibitory mole- cules fill the lesion site providing both a physical and chemical barrier to regenerating axons. Dec orin, a small leucine-rich chondroitin-dermatan sulphate proteoglycan expressed by neurons and astrocytes in the central nervous system, is both anti-fibrotic and anti-inflammatory and attenu- ates the formation and partial dissolution of established and chronic scars. Here, we discuss the potential of using Decorin to antagonise scarring in the central nervous system. 相似文献
992.
Yu Sun Hayley Reynolds Darren Wraith Scott Williams Mary E. Finnegan Catherine Mitchell Declan Murphy Martin A. Ebert Annette Haworth 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2017,40(1):39-49
The performance of a support vector machine (SVM) algorithm was investigated to predict prostate tumour location using multi-parametric MRI (mpMRI) data. The purpose was to obtain information of prostate tumour location for the implementation of bio-focused radiotherapy. In vivo mpMRI data were collected from 16 patients prior to radical prostatectomy. Sequences included T2-weighted imaging, diffusion-weighted imaging and dynamic contrast enhanced imaging. In vivo mpMRI was registered with ‘ground truth’ histology, using ex vivo MRI as an intermediate registration step to improve accuracy. Prostate contours were delineated by a radiation oncologist and tumours were annotated on histology by a pathologist. Five patients with minimal imaging artefacts were selected for this study. A Gaussian kernel SVM was trained and tested on different patient data subsets. Parameters were optimised using leave-oneout cross validation. Signal intensities of mpMRI were used as features and histology annotations as true labels. Prediction accuracy, as well as area under the curve (AUC) of the receiver operating characteristics (ROC) curve, were used to assess performance. Results demonstrated the prediction accuracy ranged from 70.4 to 87.1% and AUC of ROC ranged from 0.81 to 0.94. Additional investigations showed the apparent diffusion coefficient map from diffusion weighted imaging was the most important imaging modality for predicting tumour location. Future work will incorporate additional patient data into the framework to increase the sensitivity and specificity of the model, and will be extended to incorporate predictions of biological characteristics of the tumour which will be used in bio-focused radiotherapy optimisation. 相似文献
993.
Mary Ellen Goldberg 《Veterinary Nursing Journal》2017,32(2):37-44
Chronic pain can be found in all mammals that have a nociceptive pathway. It is defined as pain that extends beyond the normal time of healing. This article deals with chronic pain that affects canine patients. Chronic pain and depression have both been shown to occur in mammals. Chronic pain can be divided into inflammatory pain, non-osteoarthritis–non-malignant pain and cancer pain. The pet owner is key in the recognition of chronic pain in dogs. There are validated chronic pain scales available for dogs. The article will discuss various examples of chronic pain that affects dogs and ways to alleviate the effects of this pain in selected disease processes. 相似文献
994.
995.
996.
Mary E. McCall 《Gerontology & geriatrics education》2017,38(1):47-60
ABSTRACTThis article examines the similarities and differences in the education and training of gerontologists and others who work with older people in Sweden and the United States. It outlines the aging trends in both countries and assesses the level of training for those who provide care in a variety of fields. Both countries are aging, but the programs for gerontological training are quite different in the two countries, reflecting underlying cultural values. Sweden’s education is generally more oriented toward the integration of some aging education in more disciplinary fields, such as nursing and social work and thus could benefit from more specialized, aging-specific courses. The United States is highly specialized, with multiple programs in various subfields of aging (e.g., geropsychology; aging services administration) and could benefit from integrating more aging knowledge into courses in other disciplines. The authors challenge professionals to consider if there is a basic but global curriculum and/or set of competencies in gerontology that could be agreed upon. As an increasingly global village, the ability to share and learn is more easily achievable. Sweden and the United States have much to learn from each other in terms of appropriately educating and training those who support our older people. 相似文献
997.
998.
Baumrucker Craig R. Macrina Ann L. Bruckmaier Rupert M. 《Journal of mammary gland biology and neoplasia》2021,26(4):419-453
Journal of Mammary Gland Biology and Neoplasia - Colostrogenesis is a separate and unique phase of mammary epithelial cell activity occurring in the weeks before parturition and rather abruptly... 相似文献
999.
Olöf Birna Kristjansdottir André Vågan Margrét Hrönn Svavarsdóttir Hilde Blindheim Børve Kari Hvinden Veerle Duprez Ann Van Hecke Lena Heyn Hilde Strømme Una Stenberg 《Patient education and counseling》2021,104(5):1030-1048
ObjectivesTo provide overview of research on training interventions for healthcare providers aimed at promoting competencies in delivering group-based patient education.MethodsA systematic literature search identified relevant studies. Data was extracted on training details, study design, outcomes and experiences. Results were summarized and qualitative data analyzed using content analysis.ResultsTwenty-seven studies exploring various training interventions were included. Ten studies used qualitative methods, eight quantitative and nine mixed methods. Use of a comparison group, validated instruments and follow-up measures was rare. Healthcare providers’ reactions to training were mostly positive. Several studies indicated positive short-term effects on self-efficacy and knowledge. Results on observed skills and patient outcomes were inconclusive. Results on healthcare providers’ experience of delivery of group-based patient education following training were categorized into 1) Benefits of training interventions, 2) Barriers to implementation and 3) Delivery support.ConclusionsFurther evaluation of training for healthcare providers delivering group-based patient education is needed before conclusions on training efficacy can be drawn. The results indicate an expanding research field still in maturation.Practice implicationsEfficacy studies evaluating theoretically grounded training with clear attention on group facilitation and follow-up support are needed. Inclusion of validated instruments and long-term outcomes is encouraged. 相似文献
1000.
Rowlison Tricia Ottinger Mary Ann Comizzoli Pierre 《Journal of assisted reproduction and genetics》2021,38(8):2061-2071
Journal of Assisted Reproduction and Genetics - Extracellular vesicles (EVs) secreted by the epididymal epithelium transfer key factors to maturing spermatozoa. Using an in vitro system previously... 相似文献