全文获取类型
收费全文 | 1736709篇 |
免费 | 168282篇 |
国内免费 | 6855篇 |
专业分类
耳鼻咽喉 | 24533篇 |
儿科学 | 57787篇 |
妇产科学 | 43390篇 |
基础医学 | 243771篇 |
口腔科学 | 46127篇 |
临床医学 | 180782篇 |
内科学 | 360494篇 |
皮肤病学 | 43570篇 |
神经病学 | 153296篇 |
特种医学 | 61949篇 |
外国民族医学 | 447篇 |
外科学 | 258575篇 |
综合类 | 30064篇 |
现状与发展 | 73篇 |
一般理论 | 570篇 |
预防医学 | 142442篇 |
眼科学 | 36976篇 |
药学 | 119467篇 |
6篇 | |
中国医学 | 4751篇 |
肿瘤学 | 102776篇 |
出版年
2021年 | 17990篇 |
2020年 | 18438篇 |
2019年 | 26845篇 |
2018年 | 35481篇 |
2017年 | 30294篇 |
2016年 | 32609篇 |
2015年 | 35214篇 |
2014年 | 47797篇 |
2013年 | 63088篇 |
2012年 | 67244篇 |
2011年 | 70260篇 |
2010年 | 50222篇 |
2009年 | 47361篇 |
2008年 | 62778篇 |
2007年 | 63861篇 |
2006年 | 65163篇 |
2005年 | 60849篇 |
2004年 | 57306篇 |
2003年 | 53401篇 |
2002年 | 51858篇 |
2001年 | 69234篇 |
2000年 | 70133篇 |
1999年 | 59407篇 |
1998年 | 19081篇 |
1997年 | 17426篇 |
1996年 | 16981篇 |
1995年 | 16179篇 |
1994年 | 14117篇 |
1993年 | 13003篇 |
1992年 | 45084篇 |
1991年 | 44260篇 |
1990年 | 42472篇 |
1989年 | 40339篇 |
1988年 | 37334篇 |
1987年 | 36172篇 |
1986年 | 34606篇 |
1985年 | 32781篇 |
1984年 | 24681篇 |
1983年 | 21010篇 |
1982年 | 12840篇 |
1979年 | 22042篇 |
1978年 | 15790篇 |
1977年 | 13057篇 |
1976年 | 12596篇 |
1975年 | 12999篇 |
1974年 | 15803篇 |
1973年 | 15495篇 |
1972年 | 14395篇 |
1971年 | 13387篇 |
1970年 | 12409篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
92.
93.
Anne E. Kazak Fang Fang Chen Wei‐Ting Hwang Martha A. Askins Gabriela Vega E. Anders Kolb Anne Reilly Lamia P. Barakat 《Pediatric blood & cancer》2020,67(2)
Purpose: Family psychosocial risk in pediatric oncology can be assessed using the Psychosocial Assessment Tool (PAT), a brief parent report screener based on the Pediatric Psychosocial Preventative Health Model (PPPHM; universal, targeted, and clinical). However, little is known about risk over the course of treatment and its association with medical and psychosocial healthcare utilization. Methods: Primary caregivers of children with cancer participated in this prospective multisite investigation, completing the PAT at diagnosis (T1; n = 396) and 6 months later (T2; n = 304). Healthcare utilization data were extracted from electronic health records. Results: The distribution of PPPHM risk levels at T1 and T2 was highly consistent for the samples. Two‐thirds of families remained at the same level of risk, 18% decreased and 16% increased risk level. Risk was not related to sociodemographic or treatment variables. The PAT risk score correlated with psychosocial contacts over the 6‐month period. Conclusions: Although the majority of families reported universal (low) risk on the PAT and were stable in their risk level over 6 months, reassessing risk is helpful in identifying those families who report higher level of risk during treatment than at diagnosis. PAT scores were related to psychosocial services that are provided to most but not all families and could be tailored more specifically to match risk and delivery of evidence‐based care. 相似文献
94.
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
95.
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96.
Notfall + Rettungsmedizin - 相似文献
97.
98.
99.