全文获取类型
收费全文 | 31049篇 |
免费 | 2683篇 |
国内免费 | 656篇 |
专业分类
耳鼻咽喉 | 394篇 |
儿科学 | 1281篇 |
妇产科学 | 367篇 |
基础医学 | 3135篇 |
口腔科学 | 321篇 |
临床医学 | 6728篇 |
内科学 | 3120篇 |
皮肤病学 | 113篇 |
神经病学 | 1678篇 |
特种医学 | 1499篇 |
外科学 | 2760篇 |
综合类 | 5223篇 |
现状与发展 | 1篇 |
一般理论 | 3篇 |
预防医学 | 3702篇 |
眼科学 | 230篇 |
药学 | 2099篇 |
258篇 | |
中国医学 | 1057篇 |
肿瘤学 | 419篇 |
出版年
2024年 | 76篇 |
2023年 | 645篇 |
2022年 | 1123篇 |
2021年 | 1616篇 |
2020年 | 1678篇 |
2019年 | 1258篇 |
2018年 | 1177篇 |
2017年 | 1276篇 |
2016年 | 1191篇 |
2015年 | 1192篇 |
2014年 | 2542篇 |
2013年 | 2720篇 |
2012年 | 2069篇 |
2011年 | 2081篇 |
2010年 | 1665篇 |
2009年 | 1508篇 |
2008年 | 1429篇 |
2007年 | 1333篇 |
2006年 | 1126篇 |
2005年 | 992篇 |
2004年 | 799篇 |
2003年 | 663篇 |
2002年 | 489篇 |
2001年 | 421篇 |
2000年 | 358篇 |
1999年 | 315篇 |
1998年 | 258篇 |
1997年 | 252篇 |
1996年 | 213篇 |
1995年 | 197篇 |
1994年 | 191篇 |
1993年 | 155篇 |
1992年 | 166篇 |
1991年 | 118篇 |
1990年 | 117篇 |
1989年 | 98篇 |
1988年 | 97篇 |
1987年 | 91篇 |
1986年 | 78篇 |
1985年 | 67篇 |
1984年 | 84篇 |
1983年 | 50篇 |
1982年 | 59篇 |
1981年 | 49篇 |
1980年 | 43篇 |
1979年 | 39篇 |
1978年 | 36篇 |
1977年 | 47篇 |
1976年 | 30篇 |
1975年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
《Sleep medicine》2020
Study objectivesTo analyze the association between sleep-related symptoms and sleep length in parents and their children in relation to other risk factors in both generations.MethodThe participants were parents (n = 5,855, age 54.3 ± 6.5 years, 45.2% men) who participated in the community-based Respiratory Health in Northern Europe (RHINE) study and one random member of their adult offspring (n = 5,855, age 30.2 ± 7.7 years, 41.5% men) who participated in the Respiratory Health in Northern Europe, Spain and Australia (RHINESSA) study. Both generations responded to identical questionnaires on sleep symptoms, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), snoring, nocturnal sweating, nocturnal gastroesophageal reflux (nGER), sleep time and excessive daytime sleepiness (EDS). Insomnia was defined as either, or both, DIS and DMS in combination with EDS.ResultsAll sleep variables except nocturnal sweating were more common in offspring whose parents had reported the same symptom. After adjusting for age, gender, BMI, smoking, physical activity, education, center and parents' total number of children, there were independent associations between sleep symptoms in parents and offspring for DIS (adj. OR, 95% CI: 1.52, 1.20–1.93), DMS (1.34, 1.15–1.56), snoring (1.45, 1.15,1.83), nGER (1.65, 1.15–2.37), insomnia (1.39, 1.13–1.73), short sleep time (<6 h/night) (2.51, 1.72–3.68) and EDS (1.48, 1.26,1.72). There were no independent relationships between symptoms in parents and offspring for EMA, nocturnal sweating or long sleep time (>9 h/night).ConclusionThe familiar aggregation of many sleep disturbances was not explained by investigated lifestyle and environmental factors. This supports a heritable factor in sleep problems. 相似文献
42.
43.
44.
Yu-yan LI Jun-qing WU Yu-ming SHF Shang-chun WU 《生殖与避孕(英文版)》2006,17(3):158-163
Since the International Conference on Population and Development held in Cairo in 1994, and the Fourth World Conference on Women held in Beijing in 1995, the international organizations and public health communities have paid more attention to reproductiv… 相似文献
45.
A. Taytard J. F. Tessier J. G. Faugere J. Vergeret P. Freour 《European journal of epidemiology》1988,4(3):326-330
Professional exposure to vegetable dusts affect the respiratory function of the exposed subjects. A previous survey conducted in an industrial flour-mill demonstrated a higher frequency of respiratory symptoms in workers compared to a control group. Ten subjects employed in a work site particularly exposed to dust were studied. Each subject answered a questionnaire and performed on Mondays and Fridays, at the begenning and end of his work shift, a flow volume curve and an isocapnic hyperventilation test. The aerobiology of the professional environment was also measured. We noted: 1) in the flow volume curves: a drop in the FEV1 during the Monday morning shift, a significant difference between the FEV1 (p<0.05) and the MMEFR 25–75 (p<0.05) measured at 6 am on Monday and Friday, and between the MMEFR 25–75 values obtained at 12 noon on Monday and Friday (p<0.05). 2) after isocapnic hyperventilation, a significant drop in the MMEFR 25–75 at 6 am on Monday (p<0.01) and in the FEV1 and MMEFR 25–75 at 12 noon on Mondays (p<0.05), a significant drop in the FEV1 at 1 pm on Monday (p<0.01). 相似文献
46.
Zoï Kapoula Maria Pia Bucci Frederic Jurion Julie Ayoun Farzaneh Afkhami Dominique Brémond-Gignac 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,245(7):931-936
Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative
problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children.
Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and
divergence capacities were evaluated at two distances (30 cm and 400 cm).
Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was
significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more
reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and
12 pD, at far and near).
Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently
from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct
control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits
are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence
and divergence subsystems. 相似文献
47.
心房颤动(房颤)的导管消融治疗技术是近年来心血管病治疗领域最重要的进展之一[1-2].这一技术目前在国内的临床应用已越来越广泛,能够开展这一技术的医生和单位也越来越多. 相似文献
48.
Marcos Ribeiro Luciene Angelini Priscila Games Robles-Ribeiro Rafael Stelmach Ubiratan de Paula Santos Mario Terra-Filho 《The Journal of asthma》2007,44(5):371-375
Background. The European Community Respiratory Health Survey (ECRHS) questionnaire was planned to answer questions about the distribution of asthma. Our objective was to determine the cultural equivalence of the ECRHS into the Brazilian-Portuguese language. Methods. We translated the ECRHS according to international criteria. Results. Small cultural adaptations were necessary. Among the 80 participating patients, the Cronbach indices were higher (0.98-1.00) and the Kappa indices varied from 0.77 to 1.00. Conclusion. The study suggests that the Brazilian version of the ECRHS is conceptually equivalent to the original and similarly reliable and may be used in international studies involving Portuguese-speaking respiratory patients. 相似文献
49.
Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons. 相似文献
50.
探索临床技能培训和提高学生临床实践能力的有效方法.通过培训前考核、观看教学片、指导教师示范、模拟练习、现场点评、培训后考核等方式,比较培训前后考核成绩.通过短期集中培训,使实习生在临床技能方面快速提高.学生们很快掌握了临床基本技能操作规范,为更好地投入到临床实习打下了良好的基础. 相似文献