全文获取类型
收费全文 | 4605篇 |
免费 | 316篇 |
国内免费 | 28篇 |
学科分类
医药卫生 | 4949篇 |
出版年
2023年 | 40篇 |
2022年 | 42篇 |
2021年 | 151篇 |
2020年 | 129篇 |
2019年 | 179篇 |
2018年 | 223篇 |
2017年 | 171篇 |
2016年 | 177篇 |
2015年 | 193篇 |
2014年 | 272篇 |
2013年 | 316篇 |
2012年 | 432篇 |
2011年 | 431篇 |
2010年 | 248篇 |
2009年 | 192篇 |
2008年 | 264篇 |
2007年 | 231篇 |
2006年 | 210篇 |
2005年 | 187篇 |
2004年 | 149篇 |
2003年 | 128篇 |
2002年 | 113篇 |
2001年 | 36篇 |
2000年 | 41篇 |
1999年 | 34篇 |
1998年 | 20篇 |
1997年 | 13篇 |
1996年 | 24篇 |
1995年 | 20篇 |
1994年 | 14篇 |
1993年 | 18篇 |
1992年 | 17篇 |
1991年 | 22篇 |
1990年 | 24篇 |
1989年 | 18篇 |
1988年 | 14篇 |
1987年 | 26篇 |
1986年 | 24篇 |
1985年 | 13篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 11篇 |
1979年 | 5篇 |
1978年 | 5篇 |
1972年 | 4篇 |
1971年 | 8篇 |
1970年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有4949条查询结果,搜索用时 31 毫秒
1.
2.
3.
Josh Greenstein Devjani Das Josie Acuna Monica Kapoor Cara Brown Abbas Husain Brendan Lally Barry Hahn 《The American journal of emergency medicine》2019,37(2):313-316
Background
In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.Objectives
The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.Methods
This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.Results
A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.Conclusions
In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation. 相似文献4.
Distinct genetic alterations and luminal molecular subtype in nested variant of urothelial carcinoma
5.
6.
Asim Ghaffar Abbas A. Dehghani-Sanij Sheng Quan Xie 《Disability and rehabilitation. Assistive technology》2020,15(3):256-270
AbstractPurpose: Ambulation is an important objective for people with pathological gaits. Exoskeleton robots can assist these people to complete their activities of daily living. There are exoskeletons that have been presented in literature to assist the elderly and other pathological gait users. This article presents a review of the degree of support required in the elderly and neurological gait disorders found in the human population. This will help to advance the design of robot-assisted devices based on the needs of the end users.Methods: The articles included in this review are collected from different databases including Science Direct, Springer Link, Web of Science, Medline and PubMed and with the purpose to investigate the gait parameters of elderly and neurological patients. Studies were included after considering the full texts and only those which focus on spatiotemporal, kinematic and kinetic gait parameters were selected as they are most relevant to the scope of this review. A systematic review and meta-analysis were conducted.Results: The meta-analysis report on the spatiotemporal, kinematic and kinetic gait parameters of elderly and neurological patients revealed a significant difference based on the type and level of impairment. Healthy elderly population showed deviations in the gait parameters due to age, however, significant difference is observed in the gait parameters of the neurological patients.Conclusion: A level of agreement was observed in most of the studies however the review also noticed some controversies among different studies in the same group. The review on the spatiotemporal, kinematics and kinetic gait parameters will provide a summary of the fundamental needs of the users for the future design and development of robotic assistive devices.
- Implications for rehabilitation
The support requirements provide the foundation for designing assistive devices.
The findings will be crucial in defining the design criteria for robot assistive devices.
7.
Raya Saab MD Anas Obeid MD Fatiha Gachi MD Houda Boudiaf MD Lilit Sargsyan MD Khulood Al-Saad MD Tamar Javakhadze MD Azim Mehrvar MD Sawsan Sati Abbas MD Yasir Saadoon Abed Al-Agele MD Salma Al-Haddad MD Mouroge Hashim Al Ani MD Suleiman Al-Sweedan MD Amani Al Kofide MD Wasil Jastaniah MD Nisreen Khalifa MD Elie Bechara MD Malek Baassiri MD Peter Noun MD Jamila El-Houdzi MD Mohammed Khattab MD Krishna Sagar Sharma MD Yasser Wali MD Naureen Mushtaq MD Aliya Batool MD Mahwish Faizan MD Muhammad Rafie Raza MD Mohammad Najajreh MD Mohammed Awad Mohammed Abdallah MD Ghada Sousan MD Khaled M. Ghanem MD Ulker Kocak MD Tezer Kutluk MD Hacı Ahmet Demir MD Hamoud Hodeish MD Samar Muwakkit MD Asim Belgaumi MD Abdul-Hakim Al-Rawas MD Sima Jeha MD 《Cancer》2020,126(18):4235-4245
8.
Reza Zadali Samad Nejad Ebrahimi Zahra Tofighi Ali Es-haghi Matthias Hamburger Marcel Kaiser Massimiliano D
Ambola Nunziatina De Tommasi Abbas Hadjiakhoondi 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2020,28(2):455
PurposeZhumeria majdae, a unique species of the Zhumeria genus, is an endemic Iranian plant in the Lamiaceae family. Phytochemical investigation and biological activity of this plant are rarely reported. The current study aimed to find new antiprotozoal compounds from the roots of Z. majdae and to determine the absolute configuration of isolated compounds by circular dichroism.MethodsThe extraction process from roots and aerial parts of Z. majdae was carried out by hexane, ethyl acetate and methanol followed by testing their antiprotozoal effects against Leishmania donovani, Trypanosoma brucei rhodesiense, T. cruzi, and Plasmodium falciparum, respectively. Structure elucidation was done using 1D and 2D NMR spectroscopy and HREIMS spectrometry. In addition, experimental and theoretical circular dichroism spectroscopy was used to establish absolute configuration.ResultsIn comparison with aerial parts, the hexane extract from roots showed superior activity against T. b. rhodesiense, L. donovani and P. falciparum with IC50 values of 5.4, 1.6 and 2.1 μg/ml, respectively. From eight abietane-type diterpenoids identified in roots, six were reported for the first time in the genus Zhumeria. 11,14-dihydroxy-8,11,13-abietatrien-7-one (6) exhibited a promising biological activity against P. falciparum (IC50 8.65 μM), with a selectivity index (SI) of 4.6, and lanugon Q (8) showed an IC50 value of 0.13 μM and SI of 15.4 against T. b. rhodesiense.ConclusionAltogether, according to the results, of 8 isolated compounds, dihydroxy-8,11,13-abietatrien-7-one (6) and lanugon Q (8) exhibited a promising activity against T. b. rhodesiense and P. falciparum. In conclusion, these compounds could be potential candidates for further analysis and may serve as lead compounds for the synthesis of antiprotozoal agents. Open in a separate windowGraphical abstractElectronic supplementary materialThe online version of this article (10.1007/s40199-020-00345-w) contains supplementary material, which is available to authorized users. 相似文献
9.
10.