全文获取类型
收费全文 | 6235篇 |
免费 | 347篇 |
国内免费 | 106篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 33篇 |
妇产科学 | 13篇 |
基础医学 | 463篇 |
口腔科学 | 25篇 |
临床医学 | 474篇 |
内科学 | 969篇 |
皮肤病学 | 21篇 |
神经病学 | 791篇 |
特种医学 | 102篇 |
外科学 | 105篇 |
综合类 | 469篇 |
预防医学 | 327篇 |
眼科学 | 28篇 |
药学 | 2669篇 |
1篇 | |
中国医学 | 93篇 |
肿瘤学 | 91篇 |
出版年
2023年 | 33篇 |
2022年 | 35篇 |
2021年 | 103篇 |
2020年 | 99篇 |
2019年 | 127篇 |
2018年 | 132篇 |
2017年 | 171篇 |
2016年 | 164篇 |
2015年 | 156篇 |
2014年 | 320篇 |
2013年 | 865篇 |
2012年 | 285篇 |
2011年 | 328篇 |
2010年 | 305篇 |
2009年 | 308篇 |
2008年 | 345篇 |
2007年 | 308篇 |
2006年 | 276篇 |
2005年 | 239篇 |
2004年 | 184篇 |
2003年 | 216篇 |
2002年 | 171篇 |
2001年 | 142篇 |
2000年 | 143篇 |
1999年 | 117篇 |
1998年 | 82篇 |
1997年 | 82篇 |
1996年 | 74篇 |
1995年 | 77篇 |
1994年 | 76篇 |
1993年 | 67篇 |
1992年 | 46篇 |
1991年 | 31篇 |
1990年 | 35篇 |
1989年 | 31篇 |
1988年 | 29篇 |
1987年 | 57篇 |
1986年 | 35篇 |
1985年 | 68篇 |
1984年 | 43篇 |
1983年 | 26篇 |
1982年 | 36篇 |
1981年 | 32篇 |
1980年 | 39篇 |
1979年 | 36篇 |
1978年 | 30篇 |
1977年 | 25篇 |
1976年 | 24篇 |
1975年 | 10篇 |
1974年 | 11篇 |
排序方式: 共有6688条查询结果,搜索用时 15 毫秒
1.
2.
3.
《Clinical lung cancer》2020,21(2):171-176
BackgroundPatients with lung cancer continue to smoke owing to complex factors. Failure to quit smoking (defined as nicotine dependence) is significantly associated with genetic status. This study aimed to investigate the relationship between polymorphisms in nicotine dependence genes and smoking status after the diagnosis of lung cancer.Patients and MethodsA total of 240 patients with lung cancer were included from July 2017 to March 2018. According to the actual smoking condition after lung cancer diagnosis, eligible patients were divided into 3 groups: the never-smoking group, the failure to quit smoking group, and the successful smoking cessation group. Fagerstrom Test for Nicotine Dependence scores were used to evaluate the smoking status of each group. Three nicotine-dependent genes with 6 loci were detected.ResultsAmong the 240 patients, 86 were never-smokers, 51 failed to quit smoking, and 104 successfully quit smoking. The initial age of smoking in the failure to quit smoking group was significantly younger than those in the successful smoking cessation group (P = .001). There was a significant difference in the GG and AG and AA genotype distributions of CHRNA3 (rs578776) among the 3 groups (P = .003). There was also a significant difference in the distribution of CHRNA4 (rs2229959) genotypes among the 3 groups (P = .003). However, there was no significant difference in the genotype distribution of CHRNA5 (rs588765) among the 3 groups (P = .277).ConclusionsGene polymorphisms of CHRNA3 (rs578776) and CHRNA4 (rs1044396 and rs2229959) were associated with the success of smoking cessation after the diagnosis of lung cancer, which should be considered in the management of smoking cessation after patients are diagnosed with lung cancer. 相似文献
4.
Björn Delfs Ralf-Peter Kapsch Ndimofor Chofor Hui Khee Looe Dietrich Harder Björn Poppe 《Zeitschrift für medizinische Physik》2019,29(1):39-48
The frequently applied narrow and non-standard transverse dose profiles of intensity modulated photon-beam radiotherapy, lacking lateral secondary electron equilibrium, require the use of high-resolution dosimetry detectors, and small air-filled detectors are recommended as the reference detectors for cross-calibration of the high-resolution detectors. The present study focuses on the dosimetric properties of a novel cylindrical ionization chamber, the PTW Semiflex 3D 31021. The chamber's effective point of measurement was found to lie at (0.41 ± 0.04) r downstream the tip of the inner surface of the spherical front wall in the axial orientation and (0.46 ± 0.04) r upstream the chamber axis in the radial orientation. Due to its symmetrical design, the sigma values of its lateral dose response functions for all chamber's orientations are the same (2.10 ± 0.05 mm). The polarity correction factors obtained in this work do not exceed 0.1% and the saturation correction factor was below 1% up to a dose-per-pulse value of 0.956 mGy. The radiation quality correction factor kQ of the chamber as a function of the tissue-phantom-ratio, TPR20,10, has been calculated by Monte Carlo simulation and has been determined experimentally at the German Metrology Institute (Physikalisch-Technische Bundesanstalt, PTB). The values of the non-reference condition correction factor kNR have been Monte-Carlo-calculated for use of the chamber at various depths and field sizes. 相似文献
5.
6.
7.
8.
《Gaceta sanitaria / S.E.S.P.A.S》2020,34(6):615-623
ObjectiveTo evaluate the impact of the Plan for the promotion of personal autonomy and prevention of disability in Andalusia (2016-2020) in 13 public administrations during the first year of its implementation; and to analyse the usability and feasibility of the impact assessment ladder used.MethodThe Plan addresses the promotion of personal autonomy and the prevention of disabilities and dependencies through a multisectoral approach. It is structured in strands or lines of work, objectives and actions that have been assessed through the Adoption Impact Ladder (AIL). The analysis of the face validity, feasibility and inter-rater reliability of the impact assessment ladder was carried out in 30 actions of the Plan that were rated by 20 experts from the 13 ministries and public agencies involved in the Plan, and an external rater.Results176 actions and programmes were launched in 2017. Of these, 67.2% were implemented during the first year. Only one of the 16 objectives had no action initiated during the first year. Moreover, 7 out of 15 objectives implemented were fully multisectoral involving more than three Regional Ministries. The face validity, feasibility and inter-rater reliability of the AIL were good (κ: 0.72).ConclusionsThis Plan has provided a novel framework to coordinate a broad range of proposed policies and actions within the public administration of Andalusia. For the first time, a multisectoral impact analysis has been conducted providing an effective guide for monitoring, planning and setting public priorities in health, social services, ageing and disabilities. 相似文献
9.
10.