全文获取类型
收费全文 | 84211篇 |
免费 | 6030篇 |
国内免费 | 1676篇 |
专业分类
耳鼻咽喉 | 3188篇 |
儿科学 | 1033篇 |
妇产科学 | 1534篇 |
基础医学 | 2319篇 |
口腔科学 | 3235篇 |
临床医学 | 8087篇 |
内科学 | 8070篇 |
皮肤病学 | 704篇 |
神经病学 | 4824篇 |
特种医学 | 1883篇 |
外国民族医学 | 20篇 |
外科学 | 27364篇 |
综合类 | 11371篇 |
现状与发展 | 6篇 |
一般理论 | 2篇 |
预防医学 | 2960篇 |
眼科学 | 4771篇 |
药学 | 3576篇 |
181篇 | |
中国医学 | 942篇 |
肿瘤学 | 5847篇 |
出版年
2024年 | 1150篇 |
2023年 | 2439篇 |
2022年 | 3541篇 |
2021年 | 4596篇 |
2020年 | 4527篇 |
2019年 | 3703篇 |
2018年 | 3548篇 |
2017年 | 3134篇 |
2016年 | 3149篇 |
2015年 | 3167篇 |
2014年 | 6198篇 |
2013年 | 5807篇 |
2012年 | 4774篇 |
2011年 | 5013篇 |
2010年 | 4009篇 |
2009年 | 3814篇 |
2008年 | 3627篇 |
2007年 | 3590篇 |
2006年 | 3154篇 |
2005年 | 2771篇 |
2004年 | 2382篇 |
2003年 | 1883篇 |
2002年 | 1476篇 |
2001年 | 1419篇 |
2000年 | 1227篇 |
1999年 | 1110篇 |
1998年 | 912篇 |
1997年 | 862篇 |
1996年 | 657篇 |
1995年 | 543篇 |
1994年 | 481篇 |
1993年 | 382篇 |
1992年 | 330篇 |
1991年 | 323篇 |
1990年 | 234篇 |
1989年 | 218篇 |
1988年 | 235篇 |
1987年 | 224篇 |
1986年 | 178篇 |
1985年 | 214篇 |
1984年 | 198篇 |
1983年 | 115篇 |
1982年 | 131篇 |
1981年 | 114篇 |
1980年 | 94篇 |
1979年 | 69篇 |
1978年 | 45篇 |
1977年 | 42篇 |
1976年 | 34篇 |
1975年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
INTRODUCTION: The aim of this study was to evaluate changes in the pharyngeal and lower facial morphology in Turkish female Class III patients 1.5+/-0.4 years after mandibular setback surgery (bilateral sagittal split osteotomy), and orthodontic multi-bracket treatment. Only women with mandibular prognathism were selected because sex differences in pharyngeal airway changes were evident. MATERIAL AND METHODS: Lateral cephalograms of 25 Turkish female Class III patients (mean age: 25.4+/-2.6 years) with mandibular prognathism, were assessed before and 1.5+/-0.4 years after operation. Paired t and Pearson tests were used. RESULTS: The pharyngeal airway morphology showed significant changes in soft-palate length and posterior reference line (PRL) to point of posterior tongue. The decrease in PTV-Pg distance was correlated with the decreases in PRL-PSP, PRL-PTO and PRL-E distances. It was considered normal for the pharyngeal airway morphology to adapt after surgery to improve the hard tissue relationship. CONCLUSION: The lower facial morphology significantly changed and the pharyngeal airway narrowed 1.5+/-0.4 years after mandibular setback surgery. 相似文献
73.
Perea-Pérez B Santiago-Sáez A García-Marín F Labajo González E 《International journal of oral and maxillofacial surgery》2011,40(9):949-954
The authors propose a new checklist model adapted for ambulatory oral surgery procedures based on the ‘surgical checklist’ proposed by the WHO. The proposed document contains 18 items divided into two sets: those that must be verified before beginning surgery and those that must be verified after its completion, but prior to the patient's departure from the site where the surgery is performed. A checklist is an easy-to-use tool that requires little time but provides order, logic and systematization taking into account certain basic concepts to increase the level of patient safety. The authors think that the result is a checklist that is easy to complete and ensures that key patient safety-related matters are dealt with in this field of surgery. 相似文献
74.
Yamada K Hoshina H Arashiyama T Arasawa M Arai Y Uoshima K Tanaka M Nomura S 《Journal of prosthodontic research》2011,55(4):262-265
Purpose
The aim of this study was to develop and apply a new method for easy intraoperative adjustment of a provisional fixed full-arch restoration, in order to allow immediate implant loading following computer-guided surgery, regardless of any implant positioning errors compared to the virtual planning.Methods
In accordance with the NobelGuide™ protocol, a provisional restoration for immediate loading of six maxillary implants was prepared prior to surgery. Because small shifts between the planned and the actual implant positions were to be expected, the provisional restoration was not fabricated directly on temporary cylinders as a conventional one-piece superstructure, but was divided into two portions: six custom made abutments and a long span fixed restoration which were left unconnected. After implantation, the custom abutments were attached to the six implants to be immediately loaded, and the superstructure was cemented simultaneously to all abutments using dual cure resin cement. After the excess cement was cleaned and polished, the superstructure was then reseated. Passive fit was achieved between implants and the superstructure.Conclusion
The superstructure described in this article can be easily seated and adjusted to accommodate any possible shifts in implant positioning occurring during computer-guided surgery. Through this method uneventful immediate implant loading can be achieved in a reasonable operative time. 相似文献75.
Background: Restoration of edentulous mandibles with dental implants installed with a two‐stage or one‐stage surgical approach, yet with delayed loading, is a predictable and successful treatment. Purpose: The present prospective study evaluated the success up to 3 years of function of nonroughened machined‐surface Brånemark System implants (Nobel Biocare AB, Gothenburg, Sweden) loaded early or immediately with a fixed 12‐unit bridge. Materials and Methods: In total, 184 implants were installed in 36 patients:30 with healed bone and 6 with some remaining teeth, which were extracted simultaneously with implant installation. The provisional or final prostheses were installed 0 to 52 (mean 18.2) days later. Results: Thirteen of 184 (7.1%) implants failed within 3 months of loading in 5 of 36 (13.9%) patients:1 of 153 implants (0.7%) failed in healed bone, and 12 of 31 (39%) failed in fresh extraction sites. This consequently meant a loss of 3 of 36 (8.3%) prostheses, all in the extraction group. No implants were lost during 3 years of functional loading (16 patients, 75 implants). The average marginal bone level measured initially and after 1, 2, and 3 years was 0.8 mm (SD = 0.5), 1.0 mm (SD = 0.4), 1.1 mm (SD = 0.3), and 1.4 mm (SD = 0.5), respectively. Conclusions: Four to six Brånemark implants with nonroughened machined titanium surfaces can be loaded early or immediately with cross‐arch restorations in healed mandibulary bone, but this cannot be recommended for fresh extraction sites. 相似文献
76.
目的 探讨口腔正畸 正颌外科联合治疗前后不同阶段牙齿的变化和术后的稳定性。方法 选取 31例在北京大学口腔医学院进行口腔正畸 正颌外科联合治疗的骨性安氏III类错患者 ,对其不同阶段X线头影测量片进行研究。结果 牙齿在术前正畸阶段有明显的去代偿 ,下切牙平均唇倾 7 0 8°。在术中 ,上切牙随颌骨的旋转有直立 ,下切牙有后移。术后 ,上切牙有唇向复发 ,下切牙相对于基骨稳定。术后牙齿保持良好的咬合 ,而且主要变化发生在术后正畸阶段。结论 III类错患者在术前正畸阶段牙齿明显去代偿 ,术后上前牙稍有复发 ,下前牙相对保持稳定 相似文献
77.
Sumitha Muthu Jitendra Jethani Sriram Annavajjhala Sneha Gupta Krati Gupta Pooja Khamar 《Indian journal of ophthalmology》2020,68(12):2835
Refractive surgeries are one of most commonly performed surgeries for correcting visual impairment due to refractive errors. With the increase in demand for refractive surgeries, there is an enormous strain on the operating surgeon for delivering ideal outcomes i.e 20/20 visual acuity. Regression, under-correction and ectasia are the most dreaded complications post-refractive correction, for the surgeon as well as the patient. They have significant effects on the quantity of the vision and most importantly on the quality of life of the patient. With the advent of digital era and jobs requiring the eyes being glued to the screen for hours there has been a surge in the patients presenting with complaints of asthenopia, glare, halos, and difficulty in focusing; pointing towards diagnosis of non-strabismic binocular vision anomalies (NSBVA). NSBVA in a postrefractive surgery patient may masquerade as regression or under-correction. However, timely diagnosis of NSBVA in such patients would prevent the greater harm caused by wrongful re-correction. Home- and office-based vision therapy results in improvement in visual acuity in a large majority of these patients. This preferred practice pattern intends to guide the refractive surgeons to diagnose and treat the postrefractive surgery NSBVA following a case-based and algorithmic approach. It also emphasizes the inclusion of the binocular vision assessment as a part of the pre-operative workup for patients undergoing refractive procedures. 相似文献
78.
79.
R. E. Mark P. L. Klarenbeek G. J. M. Rutten M. M. Sitskoorn 《The Clinical neuropsychologist》2014,28(1):49-64
Neuropsychological follow-up appointments are important for patients who have had intracranial surgery because cognitive deficits are common in this population and prognosis is not always optimistic. Unfortunately some patients cancel or do not show up. The current study attempted to identify predictors of non-attendance in this population. A total of 428 patients recruited over 2 years with a scheduled neuropsychological follow-up appointment after intracranial surgery in the St. Elisabeth Hospital, Tilburg, The Netherlands were included. Demographic, clinical, and other miscellaneous variables were extracted from medical records. Of this total population, 42% were non-attenders. The predictors of non-attendance were as follows: patients who had subdural hematomas and/or malignant tumors (compared to those who had other diagnoses prior to intracranial surgery); those who had been transferred to another hospital (compared to those sent home); those who had been referred for further medical treatment before the appointment; a shorter time interval between discharge and follow-up appointment; and finally, if the patient’s home was further away from the hospital. Patients who undergo intracranial surgery are a very heterogeneous group with different needs. Neuropsychological follow-up after surgery may be important for some patients (the better-functioning and/or those with cognitive complaints) but perhaps not for others (those with more severe prognoses and/or no complaints). We provide suggestions which should increase attendance in those who could benefit from follow-up neuropsychological assessment. 相似文献