全文获取类型
收费全文 | 184998篇 |
免费 | 15980篇 |
国内免费 | 10987篇 |
专业分类
耳鼻咽喉 | 1514篇 |
儿科学 | 2653篇 |
妇产科学 | 2165篇 |
基础医学 | 20208篇 |
口腔科学 | 3396篇 |
临床医学 | 23383篇 |
内科学 | 26113篇 |
皮肤病学 | 2428篇 |
神经病学 | 8801篇 |
特种医学 | 6823篇 |
外国民族医学 | 56篇 |
外科学 | 16840篇 |
综合类 | 33868篇 |
现状与发展 | 37篇 |
一般理论 | 19篇 |
预防医学 | 15297篇 |
眼科学 | 4389篇 |
药学 | 19885篇 |
163篇 | |
中国医学 | 10417篇 |
肿瘤学 | 13510篇 |
出版年
2024年 | 533篇 |
2023年 | 2185篇 |
2022年 | 5585篇 |
2021年 | 7391篇 |
2020年 | 5670篇 |
2019年 | 4841篇 |
2018年 | 5159篇 |
2017年 | 5029篇 |
2016年 | 4939篇 |
2015年 | 7677篇 |
2014年 | 9732篇 |
2013年 | 10018篇 |
2012年 | 14749篇 |
2011年 | 15626篇 |
2010年 | 11382篇 |
2009年 | 9575篇 |
2008年 | 11691篇 |
2007年 | 11479篇 |
2006年 | 10551篇 |
2005年 | 9735篇 |
2004年 | 7444篇 |
2003年 | 7312篇 |
2002年 | 6043篇 |
2001年 | 4874篇 |
2000年 | 4262篇 |
1999年 | 3552篇 |
1998年 | 2111篇 |
1997年 | 2147篇 |
1996年 | 1568篇 |
1995年 | 1470篇 |
1994年 | 1213篇 |
1993年 | 781篇 |
1992年 | 902篇 |
1991年 | 785篇 |
1990年 | 683篇 |
1989年 | 590篇 |
1988年 | 474篇 |
1987年 | 462篇 |
1986年 | 351篇 |
1985年 | 305篇 |
1984年 | 193篇 |
1983年 | 137篇 |
1982年 | 100篇 |
1981年 | 77篇 |
1980年 | 53篇 |
1979年 | 81篇 |
1978年 | 52篇 |
1976年 | 36篇 |
1973年 | 44篇 |
1970年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Shuei-Tu Chen Ko-Hsiu Lu Hai-Lun Sun Wen-Tung Chang Ko-Huang Lue Ming-Chih Chou 《Pediatric allergy and immunology》2006,17(1):49-54
Leukotriene receptor antagonists (LTRAs) were recently added to the method of treating allergic rhinitis (AR). However, in children under 6 yr old, there has been no study about its efficacy in treating AR. We aim to compare the clinical efficacy of montelukast, cetirizine and placebo in the treatment of children from 2 to 6 yr old with perennial allergic rhinitis (PAR), to see if there are any significant differences. Sixty children were selected and treated with montelukast, or cetirizine, or placebo once daily. The efficacy of the three agents was compared with the Pediatric Rhinoconjunctivitis Quality of Life Questionnaire (PRQLQ) and Total Symptom Score (TSS) by diary. In addition, we also examined serum IgE, serum eosinophil cationic protein (ECP), blood eosinophil counts, nasal airway resistance (NAR) and eosinophil percentage in nasal smears. The results revealed that both montelukast and cetirizine were significantly efficacious compared with placebo in NAR, eosinophil percentage in nasal smears, PRQLQ, TSS and all symptom items except nasal itching, throat itching and tearing. For nasal itching, only cetirizine was significantly efficacious. On the other hand, for night sleep quality, montelukast was significantly superior to cetirizine. 相似文献
102.
103.
104.
We compared the aniseikonia, Seidel aberrations, spot diagrams, and peripheral refractive power errors of a schematic eye with a super-reversed intraocular lens (IOL) and with conventional IOLs. The results did not indicate that the super-reversed IOL performs better optically than the other IOLs, primarily because of its poorer on-axis image performance. However, this disadvantage can be overcome by aspherizing the super-reversed IOL. 相似文献
105.
过去,为了保证前段的血液供应,外直肌全麻痹的手术治疗要分2~3次完成,考虑到全麻痹的外直肌已无功能,我们提出在这种条件下可以不动含睫状前动脉的外直肌,只退后内直肌和将上,下直肌的外侧1/2移到外直肌的附着处,如此安排,可以一次手术完成治疗,这样可以缩短治疗时间,减少病人的痛苦和负担,我们治疗了7例8眼,结果比较满意。 相似文献
106.
Summary To characterize and compare the pathologic, hemodynamic and electrocardiographic changes of both transeatheter laser and electrical
energy on ventricle, 33 subendocardial myocardium lesions were induced at energy 60, 120 and 240 Joules by either transcatheter
laser irradiation or electrical shock in 7 anesthetized dogs. The following results were observed: 1) Both laser and electrical
ablation on myocardium created nonhomogeneous myocardium injury, but laser ablation caused mainly focal tissue vaporization
and necrosis, while electrical shock induced widespread tissue degenerations; 2) Both laser and electrical induced-lesion
dimensions increased parallel to the total dosage of energy; 3) Laser ablation caused mainly (90%) single ventricular premature
beats and 86 % of them occurred within the first minute after energy discharged, while ventricular tachycardias were found
in any electrical energy groups; ventricular fibrillations occurring during laser and electrical ablation were 5 % and 13
% respectively (P< 0.01): 4) A decrease in aortic blood pressure and an increase in central verous pressure induced by laser ablation were
significantly less than that produced by the same amount of electrical energy (P<0.0l). Our preliminary results have shown that transeatheter laser ablation has great potential for becoming a practical
method in the management of refractory tachycardias. 相似文献
107.
目的 :进一步探讨 MRI增强前后的准备与护理方法。材料与方法 :共增强 833例 ,男 5 85例 ,女 2 4 8例。使用顺磁性造影剂 Gd- DTPA,按 0 .2 m L/kg体重给药。其中双倍量增强 110例 ,增强前认真履行告知义务和签署同意书。发生造影剂外漏者给予鲜马铃薯片外敷。结果 :增强效果达良好以上共 82 5例 ,占 99% ,未发生严重负反应。 3例造影剂外漏 ,鲜马铃薯片外敷后 3h痊愈。结论 :增强前充分细致的准备是保证增强效果的重要因素。认真履行告知义务和签置同意书 ,不仅尊重了病人的权利 ,也是依法行医 ,保证医疗安全的需要 相似文献
108.
The authors performed a study of intraocular pressure-dependent changes in optic disc cupping in 17 adults with chronic open-angle glaucoma. Analyses with the Rodenstock Optic Nerve Head Analyzer were performed at baseline low intraocular pressure during therapy, after elevation of intraocular pressure (from therapeutic failure or noncompliance), and after reduction of intraocular pressure with successful therapy. Optic disc cupping increased significantly upon short-term increase of intraocular pressure from baseline of 20.4 +/- 2.5 mmHg to 31.1 +/- 5.9 mmHg. Optic disc cupping reverted to baseline after persistent intraocular pressure reduction to 19.3 +/- 4.8 mmHg. These data demonstrate intraocular pressure-dependent dynamic changes of optic disc cupping in patients with demonstrable glaucomatous optic nerve damage. They underscore the detrimental effect of elevated intraocular pressure and the beneficial effect of intraocular pressure reduction on optic disc cup changes. 相似文献
109.
Preexpanded distant "super-thin" intercostal perforator flaps for facial reconstruction without the need for microsurgery. 总被引:1,自引:0,他引:1
F Lu J H Gao R Ogawa H Hykusoku 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(11):1203-1208
BACKGROUND: Concept of the 'super-thin perforator flap' was introduced in 1994 by authors. Since then, various types of 'super-thin perforator flaps' were applied successfully especially for contour sensitive reconstruction such as face and neck. METHODS: Eleven patients requiring large flaps who presented with extensive disfiguring facial scar (male: seven cases, female: four cases). On the consideration of flaps' colour, texture and thickness requirements, the authors selected 'super-thin' anterior intercostal perforator flaps (AICP, range from 4 x 14 cm to 25 cm x 9 cm) for reconstruction purpose. First, tissue expanders (volume range from 800 cc to 1200 cc) were carefully inserted under the AICP. After the flaps were expanded for 2 months, distant scars were removed and the covering super-thinned flaps were transferred into recipient site. Two weeks later, pedicles in the anterior chest were cut down and flaps were transferred to replace all the left scars. RESULTS: Flap were survived without any complications. The colour, texture and thickness of the transferred flap were satisfactory, shrink of flaps were not observed after long term follow-up. The authors present a method of facial reconstruction that has the advantages of creating a large amount of thin tissue of both good colour and texture, without the need of microsurgery and few disadvantages of donor-site morbidity. The disadvantages are three-staged procedures, complications of tissue expansion and uncomfortable compulsory posture for patients. In our opinion, this is an alternative method of choice for reconstructing all large defects in the lower two-thirds of the face. 相似文献
110.
We consider a class of Cohen–Grossberg neural networks with delays. We prove the existence and global asymptotic stability of an equilibrium point and estimate the region of existence. Furthermore, we show that the trajectories of the neural networks with positive initial data will stay in the positive region if the amplification function satisfies a divergent condition. We also establish the existence of a globally attracting compact set for more general networks. We estimate this compact set explicitly in terms of the network parameters from physiological and biological models. Our results can be applied to neural networks with a wide range of activation functions which are neither bounded nor globally Lipschitz continuous such as the Lotka–Volterra model. We also give some examples and simulations. 相似文献