全文获取类型
收费全文 | 160121篇 |
免费 | 14306篇 |
国内免费 | 9908篇 |
专业分类
耳鼻咽喉 | 1741篇 |
儿科学 | 2083篇 |
妇产科学 | 2809篇 |
基础医学 | 17959篇 |
口腔科学 | 2786篇 |
临床医学 | 21041篇 |
内科学 | 24018篇 |
皮肤病学 | 1414篇 |
神经病学 | 8284篇 |
特种医学 | 5700篇 |
外国民族医学 | 74篇 |
外科学 | 17382篇 |
综合类 | 25254篇 |
现状与发展 | 35篇 |
一般理论 | 23篇 |
预防医学 | 10123篇 |
眼科学 | 4409篇 |
药学 | 16757篇 |
108篇 | |
中国医学 | 8986篇 |
肿瘤学 | 13349篇 |
出版年
2024年 | 1632篇 |
2023年 | 2349篇 |
2022年 | 5920篇 |
2021年 | 7659篇 |
2020年 | 5840篇 |
2019年 | 4976篇 |
2018年 | 5374篇 |
2017年 | 4832篇 |
2016年 | 4538篇 |
2015年 | 7046篇 |
2014年 | 8931篇 |
2013年 | 8121篇 |
2012年 | 12037篇 |
2011年 | 13099篇 |
2010年 | 8373篇 |
2009年 | 6575篇 |
2008年 | 8466篇 |
2007年 | 8453篇 |
2006年 | 8271篇 |
2005年 | 8308篇 |
2004年 | 5539篇 |
2003年 | 5027篇 |
2002年 | 4367篇 |
2001年 | 3562篇 |
2000年 | 3693篇 |
1999年 | 3670篇 |
1998年 | 2202篇 |
1997年 | 2045篇 |
1996年 | 1763篇 |
1995年 | 1590篇 |
1994年 | 1308篇 |
1993年 | 873篇 |
1992年 | 1295篇 |
1991年 | 1093篇 |
1990年 | 884篇 |
1989年 | 758篇 |
1988年 | 761篇 |
1987年 | 671篇 |
1986年 | 517篇 |
1985年 | 403篇 |
1984年 | 265篇 |
1983年 | 190篇 |
1982年 | 109篇 |
1981年 | 123篇 |
1980年 | 105篇 |
1979年 | 151篇 |
1978年 | 67篇 |
1977年 | 67篇 |
1976年 | 52篇 |
1975年 | 55篇 |
排序方式: 共有10000条查询结果,搜索用时 5 毫秒
61.
头颈部恶性肿瘤患者血清可溶性白介素2受体水平 总被引:1,自引:0,他引:1
目的:研究头颈部恶性肿瘤患者血清可溶性白介素2受体(sIL-2R)水平的变化。方法:用双抗体夹心法对60例头颈部恶性肿瘤患者,60例良性肿瘤患者以及50例健康对照者的血清sIL-2R水平进行检测。结果:头颈部恶性肿瘤患者组血清sIL-2R水平显著高于健康对照组(P<0.01),而良性肿瘤患者组血清sIL-2R水平与健康对照组无统计学差异(P>0.05)。结论:血清中高sIL-2R水平可能与头颈部恶性肿瘤的发生有相关性。 相似文献
62.
Chang WJ Lee SY Wu CC Lin CT Abiko Y Yamamichi N Huang HM 《Dental materials journal》2007,26(5):665-671
Resonance frequency (RF) analysis technology was used to design a new dental implant stability detector. To calibrate and test the performance of this novel apparatus, in vitro and in vivo models, respectively, were used. The RF values of the test implants detected using our new device and a commercially available analogous device (Osstell) were compared. Further, implant stability status was also detected clinically using our device at 2, 4, 8, and 12 weeks after surgery. A high correlation was demonstrated between the values measured with the two devices (y = 0.31x-12.45; R2 = 0.98, p < 0.05). In our clinical tests, an initial RF value above 10.0 kHz indicated that the implant was ready to accept functional loading, while values in the 4.0-10.0 kHz range reflected the need for further osseointegration. In conclusion, these results indicated that our new device might be useful in a clinical setting for evaluating the healing status of a placed implant. 相似文献
63.
目的:探讨倾斜种植体作为一种避免上颌窦植骨的方法,应用于上颌骨后牙区骨量不足患者种植修复的可靠性。方法:2005年1月—2007年12月间,21例患者共27个固定桥修复上颌后牙缺失,分别使用ITI和Br覽nemark 2种种植系统共植入78颗种植体,其中34颗种植体采用倾斜植入,44颗轴向植入。所有患者均为上颌后牙区骨量不足无法直接接受常规种植体植入。种植体植入后常规愈合3个月,除1颗种植体失败外,其余种植体均功能性负载支持固定义齿修复,修复方式为黏结固位和螺丝固位。每例患者均于负载后12、24和36个月接受临床和放射学随访检查。采用SPSS11.0软件包对数据进行统计学处理。结果:上颌有1颗轴向种植体在术后2个月时失败,倾斜种植体无失败。随访时间为36个月。上颌轴向种植体的累积存活率为97.72%,倾斜种植体的累积存活率为100%,修复成功率为100%。随访期间,种植体周围软组织保持稳定,平均探诊深度和附着水平无明显变化。结论:倾斜种植体作为一种上颌骨后牙区骨量不足患者的治疗方法是可靠的,能有效避免植骨手术,并节约治疗时间。 相似文献
64.
下颌骨应力分布的三维有限元分析 总被引:4,自引:0,他引:4
本文用三维有限元方法建立了人类下颌骨的力学模型,采用双侧下颌角加力,模拟了前牙及后牙咬合,对下颌骨的应力分布进行了计算分析。结果表明:应力在下颌骨下缘及牙槽嵴处明显,下颌内侧面应力改变较下颌外侧面明显。 相似文献
65.
Dental implants for orthodontic anchorage 总被引:7,自引:0,他引:7
Lien-Hui Huang Jeffrey Lynn Shotwell Hom-Lay Wang 《American journal of orthodontics and dentofacial orthopedics》2005,127(6):713-722
The purpose of this article is to review and update current concepts involving the use of dental implants for orthodontic anchorage. Topics to be discussed include indications, implant requirements (eg, materials, size, designs of dental implants), surgery and healing time, biomechanics and forces, loading time, implant maintenance, posttreatment considerations, and disadvantages. 相似文献
66.
目的 介绍自行研制的带控制阀种植牙手术骨粉收集器,并观察其临床应用效果.方法 选取2008年5月至2009年10月38例牙种植患者,应用自制的骨粉收集器收集种植窝制备时产生的骨碎屑,并将其用于修复种植体周围骨缺损,其中开窗式骨缺损29处,唇颊(舌)侧种植体颈部角形缺损23处.结果 所有病例术后均无创口感染及裂开,原缺损处局部形态饱满,牙龈无明显退缩,X线片示种植体与周围牙槽骨形成良好的骨结合.结论 应用自制骨粉收集器收集的骨粉修复种植体周围小型骨缺损效果良好,使用方便,具有良好的应用前景.Abstract: Objective To introduce a self-developed bone collector designed by the authors and evaluate its effect in clinical application. Methods A self-developed bone collector was used in 38 patients who underwent the dental implant operation from May 2008 to October 2009. During the operation the bone particles were harvested, which was used for the reconstruction of the bone defects around the implant simultaneously. The defects were fenestrate in 29 regions and triangle in 23 regions on buccal or lingual side of the dental implants. Results All cases had no surgical wound infection and dehiscence 7-10 days after operation. Three to six months after implantation, the X-ray showed that all the dental implants had perfect osseointergration and the alveolar bone were successfully augmented. Conclusions Bone debris harvested by self-developed bone collector could repair small peri-implant bone defects, which is simple to use in clinic. 相似文献
67.
Objectives
To investigate the effects of acidic and neutral 30% hydrogen peroxide (HP) on human tooth enamel in terms of chemical structure, mechanical property, surface morphology and tooth colour.Methods
Twenty-seven human dental blocks were obtained from premolars and randomly divided into three groups (n = 9): Group acidic HP (30% HP, pH ≈ 3.6), Group neutral HP (30% HP, pH ≈ 7.0) and Group DW (distilled water, pH ≈ 6.8). Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, atomic force microscopy (AFM) investigation, microhardness test and colour measurements were carried out before and after treatments. ATR-FTIR and Raman spectroscopy were analysed and then the carbonate:mineral ratio (C:M), Raman absolute intensity (RAI), Raman relative intensity (RRI), and laser-induced fluorescence intensity (FI) were obtained for evaluation.Results
The C:M, percentage microhardness and percentage RRI of group acidic HP decreased more significantly than those of group neutral HP (P = 0.02, P = 0.001, P < 0.001, respectively) and group DW (P = 0.01, P = 0.008, P < 0.001, respectively). Whilst group neutral HP and group DW had no statistical difference in above terms (P = 0.818, P = 0.528, P = 0.158, respectively). Significant morphological alterations were observed in group acidic HP. Group acidic HP and neutral HP had no significant difference in percentage FI (P = 0.652) and ΔE (P = 0.906).Conclusions
This study suggested that neutral 30% HP had the same efficiency in tooth bleaching and it caused less deleterious effects on enamel than acidic 30% HP. 相似文献68.
69.
Clinical evaluation of different treatment methods for oral submucous fibrosis. A 10-year experience with 150 cases 总被引:3,自引:0,他引:3
D. R. Lai H. R. Chen L. M. Lin Y. L. Huang C. C. Tsai Der-Rong Lai 《Journal of oral pathology & medicine》1995,24(9):402-406
Over a 10-year period (1982–1991), a total of 150 patients divided into two groups with varying degrees of oral submucous fibrosis (OSF) were treated by either medical or surgical therapies. Medical treatment involved (a) conservative oral administration of vitamin B-complex, buflomedial hydrochloride and topical triamcinolone acetonide 0.1%, or (b) conventional submucosal injections of a combination of dexamethasone and hyaluronidase, or (c) a combination of both (a) and (b). The surgical group was treated by the excision of fibrotic tissues and covering the defect with split-thickness skin, fresh human amnion, or buccal fat pad (BFP) grafts. Treatment was chosen according to the stage of clinical progression to gain maximal interincisal distance (ID). The cases were followed up by monthly examinations for at least two years, or when possible even longer. A combination of (a) and (b) medical treatment was satisfactory in cases of mild impairment (ID > 20 mm) but in the long term it led to symptomatic relief only. Surgical therapy, on the other hand, when accepted by the patients, led to a significant improvement of trismus in cases of severe limitation (ID < 20 mm). Following this strategy, an additional ID increase was observed in all patients. BFP grafting was particularly successful in diminishing scarring after two years as compared with the other two grafts. Together with a cessation of the betel quid chewing habit before and after therapy, these treatment regimens combined with daily mouth opening exercises were found to be necessary to manage OSF cases in early and advanced stages of progression. 相似文献
70.
Han W Yang X Huang X Hu Q Wang Z 《The British journal of oral & maxillofacial surgery》2008,46(5):376-378
The diagnosis of squamous cell carcinoma (SCC) of the tongue metastasising to the lingual lymph nodes is rare. Until now lingual lymph nodes have not been mentioned in any system of lymph node classification. We report a case of SCC of the tongue with metastases to the lymph nodes in the superficial floor of the mouth, and to levels I and II lymph nodes. We provide evidence of the existence of lingual lymph nodes, and validate the practice of removing the lymph node-bearing-tissue of the floor of the mouth during neck dissection in cancers of the oral cavity. 相似文献