全文获取类型
收费全文 | 410840篇 |
免费 | 26689篇 |
国内免费 | 3225篇 |
专业分类
耳鼻咽喉 | 5518篇 |
儿科学 | 9135篇 |
妇产科学 | 10652篇 |
基础医学 | 57700篇 |
口腔科学 | 12252篇 |
临床医学 | 33139篇 |
内科学 | 84952篇 |
皮肤病学 | 9252篇 |
神经病学 | 29656篇 |
特种医学 | 15098篇 |
外国民族医学 | 95篇 |
外科学 | 64372篇 |
综合类 | 11222篇 |
现状与发展 | 2篇 |
一般理论 | 66篇 |
预防医学 | 19985篇 |
眼科学 | 10060篇 |
药学 | 33443篇 |
7篇 | |
中国医学 | 2814篇 |
肿瘤学 | 31334篇 |
出版年
2021年 | 3663篇 |
2019年 | 3536篇 |
2018年 | 5504篇 |
2017年 | 4152篇 |
2016年 | 4227篇 |
2015年 | 4895篇 |
2014年 | 6810篇 |
2013年 | 8814篇 |
2012年 | 12108篇 |
2011年 | 12296篇 |
2010年 | 7488篇 |
2009年 | 6908篇 |
2008年 | 10993篇 |
2007年 | 11859篇 |
2006年 | 11716篇 |
2005年 | 10679篇 |
2004年 | 10047篇 |
2003年 | 9720篇 |
2002年 | 9303篇 |
2001年 | 29192篇 |
2000年 | 29727篇 |
1999年 | 24514篇 |
1998年 | 5481篇 |
1997年 | 4525篇 |
1996年 | 4070篇 |
1995年 | 3677篇 |
1994年 | 3295篇 |
1993年 | 3001篇 |
1992年 | 16467篇 |
1991年 | 15215篇 |
1990年 | 14550篇 |
1989年 | 14327篇 |
1988年 | 12962篇 |
1987年 | 12381篇 |
1986年 | 11426篇 |
1985年 | 10612篇 |
1984年 | 7125篇 |
1983年 | 5770篇 |
1982年 | 2825篇 |
1979年 | 5658篇 |
1978年 | 3436篇 |
1977年 | 3077篇 |
1976年 | 2344篇 |
1975年 | 2729篇 |
1974年 | 3180篇 |
1973年 | 2957篇 |
1972年 | 2944篇 |
1971年 | 2843篇 |
1970年 | 2600篇 |
1969年 | 2641篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
D Doummar B Roussat B Pelosse H Ducou Le Pointe M Iba-Zizen A Roubergue D Rodriguez T Billette de Villemeur 《Archives de pédiatrie》2004,11(11):1384-1388
Acute or rapidly progressive visual loss in children needs urgent attention and treatment. It may be unilateral orbilateral. Etiology depends upon the involved areas: eye ball, optic nerve, retro-chiasmatic pathways. Psychogenic origin is quite common in school-age children, however, it has to be considered last. Unilateral visual loss may be overlooked. Acute total transitory visual loss may be due to epilepsy or to migraine. Rapidly progressive visual loss may be due to retinal disease, optic neuritis or cortical blindness. Management of visual loss depends on clinical features, associated symptoms, and aspect of the optic disc. It needs collaboration between ophthalmologist,pediatrician and neuropediatrician. Retinal hemorrhages first call to mind a traumatic origin. Swelling of the optic disc may be due to increased intracranial pressure or due to optic neuritis. When the optic disc is normal it is necessary to rule out organic diseases before establishing the diagnosis of a psychogenic vision disturbance. In emergency, brain neuroimaging is the best way to diagnose intracranial mass and visualize optic pathways. 相似文献
995.
996.
997.
998.
G Gorincour F Rypens C Lapierre T Costa F Audibert Y Robitaille 《Ultrasound in obstetrics & gynecology》2006,27(1):78-80
We report the case of a fetus with a sonographic mid-gestation diagnosis of hyperechogenic cerebellum suspected to be of hemorrhagic origin on fetal brain magnetic resonance imaging (MRI). No etiological factors for fetal hemorrhage were found other than a maternal heterozygocity for factor V Leiden. Following termination of the pregnancy, autopsy confirmed the prenatal diagnosis of massive cerebellar hemorrhage without underlying vascular anomaly. As an additional tool to ultrasonography, fetal brain MRI can affirm the hemorrhagic origin of hyperechogenic cerebellar lesions, especially by showing a high signal on T1-weighted images. 相似文献
999.
The efficacy of two dry cow treatment (DCT) regimens for subclinical Staphylococcus aureus mastitis was evaluated in naturally infected dairy cows. At dry‐off, cows were assigned to two treatment groups by randomized blocks on the basis of parity and somatic cell count (SCC). Two antibiotic DCT regimens were used, namely: (1) a single intramammary infusion containing sodium nafcillin, procaine benzylpenicillin and dihydrostreptomycin; and (2) systemic cefquinome administered intramuscularly, twice at a 24‐h interval. In the intramammary (IMM) treatment group, the S. aureus intramammary infection (IMI) rate was reduced from 40% (56/140 quarters) before dry‐off to 20% (28/140) after calving. Seventy per cent (39/56) of the S. aureus‐positive quarters were negative after calving, and 13% (11/84) of the negative quarters were positive after calving. In the systemic treatment group, the S. aureus IMI rate increased from 39% (29/74 quarters) before dry‐off to 55% (41/74) after calving. Twenty‐eight per cent (8/29) of the S. aureus‐positive quarters were negative after calving and 45% (20/45) of the negative quarters were positive after calving. The odds ratio of an S. aureus‐positive quarter being negative after calving in the IMM group relative to the systemic therapy group was 44.6 (95% confidence interval = 2.1–909.1, P < 0.01). Parity, quarter, milk SCC and N‐acetyl‐β‐D‐glucosaminidase were tested in the model, and were found to have no significant effect on S. aureus cure rates or new IMI rates. The IMM treatment resulted in a higher cure rate compared with that observed in previous studies. The very low cure rate after systemic cefquinome treatment was comparable to the spontaneous cure rate observed in untreated controls in previous studies. The unfavourable results of the cefquinome systemic DCT might reflect inadequate pharmacokinetic properties of the drug regarding poor udder penetration in subclinical mastitis and short antimicrobial effect compared with the IMM treatment. 相似文献
1000.
C Schweitzer L T T Vu Y T Nguyen C Choné B Demoulin F Marchal 《The European respiratory journal》2006,28(1):89-95
The bronchomotor effects of a deep inhalation (DI) may provide relevant information about the mechanisms of exercise-induced airway obstruction in children and may be assessed by respiratory conductance (Grs) measured using the forced oscillation technique. The aims of the present study were to assess the effect of DI on Grs after exercise in relationship to the lung function response to exercise. Grs at 12 Hz using a head generator and spirometric data were measured in 62 children suspected of asthma before and 5 min after a 6-min free run. After exercise, Grs was significantly increased by DI in 38 subjects, who also showed larger Grs and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) responses to exercise than the 24 nonresponders. Stepwise regression indicated significant correlation between the response of Grs to DI and both Grs and FEV1/FVC responses to exercise. The data are consistent with exercise-induced bronchoconstriction being reversed by deep inhalation. 相似文献