全文获取类型
收费全文 | 343291篇 |
免费 | 7584篇 |
国内免费 | 407篇 |
专业分类
耳鼻咽喉 | 3360篇 |
儿科学 | 11480篇 |
妇产科学 | 6969篇 |
基础医学 | 40614篇 |
口腔科学 | 7138篇 |
临床医学 | 22003篇 |
内科学 | 68481篇 |
皮肤病学 | 5479篇 |
神经病学 | 30051篇 |
特种医学 | 13005篇 |
外国民族医学 | 1篇 |
外科学 | 48218篇 |
综合类 | 3065篇 |
一般理论 | 27篇 |
预防医学 | 37860篇 |
眼科学 | 7205篇 |
药学 | 22389篇 |
中国医学 | 1317篇 |
肿瘤学 | 22620篇 |
出版年
2023年 | 920篇 |
2022年 | 878篇 |
2021年 | 3061篇 |
2020年 | 1713篇 |
2019年 | 3276篇 |
2018年 | 26594篇 |
2017年 | 20060篇 |
2016年 | 22289篇 |
2015年 | 4521篇 |
2014年 | 4962篇 |
2013年 | 7019篇 |
2012年 | 17395篇 |
2011年 | 31706篇 |
2010年 | 23956篇 |
2009年 | 15501篇 |
2008年 | 28165篇 |
2007年 | 30912篇 |
2006年 | 9871篇 |
2005年 | 11000篇 |
2004年 | 11538篇 |
2003年 | 11947篇 |
2002年 | 9722篇 |
2001年 | 5218篇 |
2000年 | 5921篇 |
1999年 | 4399篇 |
1998年 | 973篇 |
1992年 | 2283篇 |
1991年 | 2089篇 |
1990年 | 2120篇 |
1989年 | 1778篇 |
1988年 | 1682篇 |
1987年 | 1555篇 |
1986年 | 1578篇 |
1985年 | 1489篇 |
1984年 | 1068篇 |
1983年 | 918篇 |
1979年 | 1213篇 |
1978年 | 820篇 |
1977年 | 789篇 |
1976年 | 756篇 |
1975年 | 886篇 |
1974年 | 1148篇 |
1973年 | 1174篇 |
1972年 | 1112篇 |
1971年 | 1085篇 |
1970年 | 1035篇 |
1969年 | 1109篇 |
1968年 | 1125篇 |
1967年 | 978篇 |
1966年 | 881篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Nutritional Risk in Emergency‐2017: A New Simplified Proposal for a Nutrition Screening Tool 下载免费PDF全文
62.
63.
Juan R. Ordoñana Juan F. Sánchez Romera Lucía Colodro-Conde Eduvigis Carrillo Francisca González-Javier Juan J. Madrid-Valero José J. Morosoli-García Francisco Pérez-Riquelme José M. Martínez-Selva 《Gaceta sanitaria / S.E.S.P.A.S》2018,32(1):92-95
Genetically informative designs and, in particular, twin studies, are the most widely used methodology to analyse the relative contribution of genetic and environmental factors to inter-individual variability. These studies basically compare the degree of phenotypical similarity between monozygotic and dizygotic twin pairs. In addition to the traditional estimate of heritability, this kind of registry enables a wide variety of analyses which are unique due to the characteristics of the sample. The Murcia Twin Registry is population-based and focused on the analysis of health-related behaviour. The observed prevalence of health problems is comparable to that of other regional and national reference samples, which guarantees its representativeness. Overall, the characteristics of the Registry facilitate developing various types of research as well as genetically informative designs, and collaboration with different initiatives and consortia. 相似文献
64.
Pedro F. Sánchez-López Ignacio Ruiz-Arrondo Heiko Kotter Francisco Pacheco Martínez Manuel Segovia Hernández M. Elisa Gómez Campoy 《Gaceta sanitaria / S.E.S.P.A.S》2018,32(2):181-183
Historically, no black fly (Diptera: Simuliidae) nuisance has been reported in the Murcia Region. Back in September 2016 the Ojós City Council has contacted the Regional Public Health General Directorate for help regarding a local insect nuisance, most probably based on mosquitoes. After sampling with a BG-sentinel 2 trap, collecting adult specimens with an entomological aspirator, and collect larvae and pupae on submerged giant cane stalks at the river, it turned out that Simulium sergenti was the insect species causing the nuisance. This species is not considered particularly anthropophilic; therefore, a low vector risk for human health was considered. However, the high fly density impaired the life quality of the people at the village. A management plan was recommended, treating the river with Bacillus thuringiensis var israelensis. 相似文献
65.
Comparing the Effectiveness of Dynamic Treatment Strategies Using Electronic Health Records: An Application of the Parametric g‐Formula to Anemia Management Strategies 下载免费PDF全文
66.
Xinxin Liu Jian Yang Shuang Song Hong Song Danni Ai Jianjun Zhu Yurong Jiang Yongtian Wang 《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》2018,41(2):495-505
67.
68.
69.
Usha Rani Gogoi Mrinal Kanti Bhowmik Debotosh Bhattacharjee Anjan Kumar Ghosh 《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》2018,41(4):861-879
The purpose of this study is to develop a novel breast abnormality detection system by utilizing the potential of infrared breast thermography (IBT) in early breast abnormality detection. Since the temperature distributions are different in normal and abnormal thermograms and hot thermal patches are visible in abnormal thermograms, the abnormal thermograms possess more complex information than the normal thermograms. Here, the proposed method exploits the presence of hot thermal patches and vascular changes by using the power law transformation for pre-processing and singular value decomposition to characterize the thermal patches. The extracted singular values are found to be statistically significant (p?<?0.001) in breast abnormality detection. The discriminability of the singular values is evaluated by using seven different classifiers incorporating tenfold cross-validations, where the thermograms of the Department of Biotechnology-Tripura University-Jadavpur University (DBT-TU-JU) and Database of Mastology Research (DMR) databases are used. In DMR database, the highest classification accuracy of 98.00% with the area under the ROC curve (AUC) of 0.9862 is achieved with the support vector machine using polynomial kernel. The same for the DBT-TU-JU database is 92.50% with AUC of 0.9680 using the same classifier. The comparison of the proposed method with the other reported methods concludes that the proposed method outperforms the other existing methods as well as other traditional feature sets used in IBT based breast abnormality detection. Moreover, by using Rank1 and Rank2 singular values, a breast abnormality grading (BAG) index has also been developed for grading the thermograms based on their degree of abnormality. 相似文献
70.
Chhavi Raj Bhatt Mary Redmayne Michael J. Abramson Malcolm R. Sim Christopher Brzozek Berihun M. Zeleke Geza Benke 《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》2018,41(4):985-991
The aims of this study were to evaluate the weekly and annual cumulative radiofrequency-electromagnetic field (RF-EMF) exposure attributed to mobile phone (MP) use, and assess whether a novel app (Quanta Monitor?) could be employed in a small human sample to characterise the RF-EMF exposures associated with the use of MPs. Ten participants provided their two months’ daily objective data on their MP exposures (i.e. transmitted and received power densities) attributed to different modes of MP usage such as cellular calls, cellular data and Wi-Fi. The results demonstrated that total transmitted power density (cellular phone calls, data and Wi-Fi surfing) could be many orders of magnitude higher than that from the total received power density. Of the total transmitted power density, cellular data use contributed the largest portion. Our study showed that Quanta Monitor? could be employed in prospective assessment of exposures to MPs in epidemiological studies. 相似文献