全文获取类型
收费全文 | 108338篇 |
免费 | 46001篇 |
国内免费 | 233篇 |
专业分类
耳鼻咽喉 | 1808篇 |
儿科学 | 4919篇 |
妇产科学 | 1196篇 |
基础医学 | 20284篇 |
口腔科学 | 5399篇 |
临床医学 | 15340篇 |
内科学 | 30859篇 |
皮肤病学 | 7912篇 |
神经病学 | 16679篇 |
特种医学 | 3482篇 |
外国民族医学 | 1篇 |
外科学 | 20180篇 |
综合类 | 194篇 |
一般理论 | 31篇 |
预防医学 | 6100篇 |
眼科学 | 1598篇 |
药学 | 7791篇 |
中国医学 | 1100篇 |
肿瘤学 | 9699篇 |
出版年
2023年 | 219篇 |
2022年 | 308篇 |
2021年 | 2089篇 |
2020年 | 5430篇 |
2019年 | 11522篇 |
2018年 | 10931篇 |
2017年 | 11977篇 |
2016年 | 12669篇 |
2015年 | 12629篇 |
2014年 | 12977篇 |
2013年 | 13822篇 |
2012年 | 6759篇 |
2011年 | 6836篇 |
2010年 | 10383篇 |
2009年 | 6774篇 |
2008年 | 4462篇 |
2007年 | 3318篇 |
2006年 | 3297篇 |
2005年 | 3034篇 |
2004年 | 2835篇 |
2003年 | 2730篇 |
2002年 | 2805篇 |
2001年 | 1059篇 |
2000年 | 924篇 |
1999年 | 591篇 |
1998年 | 463篇 |
1997年 | 429篇 |
1996年 | 313篇 |
1995年 | 296篇 |
1994年 | 247篇 |
1993年 | 219篇 |
1992年 | 195篇 |
1991年 | 163篇 |
1990年 | 148篇 |
1989年 | 131篇 |
1988年 | 130篇 |
1987年 | 98篇 |
1986年 | 128篇 |
1985年 | 107篇 |
1984年 | 108篇 |
1983年 | 109篇 |
1982年 | 112篇 |
1981年 | 97篇 |
1980年 | 92篇 |
1979年 | 59篇 |
1978年 | 54篇 |
1977年 | 45篇 |
1976年 | 42篇 |
1975年 | 49篇 |
1974年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
Ingmar Fleps Pierre Guy Stephen J Ferguson Peter A Cripton Benedikt Helgason 《Journal of bone and mineral research》2019,34(10):1837-1850
The majority of hip fractures in the elderly are the result of a fall from standing or from a lower height. Current injury models focus mostly on femur strength while neglecting subject-specific loading. This article presents an injury modeling strategy for hip fractures related to sideways falls that takes subject-specific impact loading into account. Finite element models (FEMs) of the human body were used to predict the experienced load and the femoral strength in a single model. We validated these models for their predicted peak force, effective pelvic stiffness, and fracture status against matching ex vivo sideways fall impacts (n = 11) with a trochanter velocity of 3.1 m/s. Furthermore, they were compared to sideways impacts of volunteers with lower impact velocities that were previously conducted by other groups. Good agreement was found between the ex vivo experiments and the FEMs with respect to peak force (root mean square error [RMSE] = 10.7%, R2 = 0.85) and effective pelvic stiffness (R2 = 0.92, RMSE = 12.9%). The FEMs were predictive of the fracture status for 10 out of 11 specimens. Compared to the volunteer experiments from low height, the FEMs overestimated the peak force by 25% for low BMI subjects and 8% for high BMI subjects. The effective pelvic stiffness values that were derived from the FEMs were comparable to those derived from impacts with volunteers. The force attenuation from the impact surface to the femur ranged between 27% and 54% and was highly dependent on soft tissue thickness (R2 = 0.86). The energy balance in the FEMS showed that at the time of peak force 79% to 93% of the total energy is either kinetic or was transformed to soft tissue deformation. The presented FEMs allow for direct discrimination between fracture and nonfracture outcome for sideways falls and bridge the gap between impact testing with volunteers and impact conditions representative of real life falls. © 2019 American Society for Bone and Mineral Research. 相似文献
14.
Ángel Becerra Héctor Trujillo Lucía Valencia Aurelio Rodríguez‐Pérez 《Brazilian Journal of Anesthesiology》2019,69(2):200-203
Background and objectives
A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.Case report
A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.Conclusion
Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma. 相似文献15.
16.
17.
18.
Hyun Jong Choi Jong Ho Moon Yun Nah Lee Hyun Su Kim Ji Su Ha Tae Hoon Lee Sang‐Woo Cha Young Deok Cho Sang‐Heum Park 《Digestive endoscopy》2015,27(7):772-775
Direct peroral cholangioscopy (POC) using an ultra‐slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra‐slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra‐slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS. 相似文献
19.
Autoimmune comorbid diseases associated with lichen planus: a nationwide case–control study
下载免费PDF全文
![点击此处可从《Journal of the European Academy of Dermatology and Venereology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
20.
M.T. Leccia N. Auffret F. Poli J.‐P. Claudel S. Corvec B. Dreno 《Journal of the European Academy of Dermatology and Venereology》2015,29(8):1485-1492
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (P. acnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety. 相似文献