全文获取类型
收费全文 | 4470篇 |
免费 | 479篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 45篇 |
儿科学 | 104篇 |
妇产科学 | 119篇 |
基础医学 | 703篇 |
口腔科学 | 51篇 |
临床医学 | 509篇 |
内科学 | 735篇 |
皮肤病学 | 44篇 |
神经病学 | 432篇 |
特种医学 | 141篇 |
外科学 | 667篇 |
综合类 | 105篇 |
一般理论 | 2篇 |
预防医学 | 463篇 |
眼科学 | 57篇 |
药学 | 414篇 |
中国医学 | 3篇 |
肿瘤学 | 359篇 |
出版年
2021年 | 51篇 |
2020年 | 35篇 |
2019年 | 58篇 |
2018年 | 69篇 |
2017年 | 55篇 |
2016年 | 63篇 |
2015年 | 80篇 |
2014年 | 107篇 |
2013年 | 145篇 |
2012年 | 226篇 |
2011年 | 191篇 |
2010年 | 114篇 |
2009年 | 89篇 |
2008年 | 158篇 |
2007年 | 191篇 |
2006年 | 180篇 |
2005年 | 172篇 |
2004年 | 165篇 |
2003年 | 160篇 |
2002年 | 146篇 |
2001年 | 174篇 |
2000年 | 167篇 |
1999年 | 117篇 |
1998年 | 61篇 |
1997年 | 63篇 |
1996年 | 72篇 |
1995年 | 50篇 |
1994年 | 49篇 |
1993年 | 54篇 |
1992年 | 139篇 |
1991年 | 122篇 |
1990年 | 110篇 |
1989年 | 124篇 |
1988年 | 112篇 |
1987年 | 89篇 |
1986年 | 68篇 |
1985年 | 76篇 |
1984年 | 66篇 |
1983年 | 40篇 |
1982年 | 33篇 |
1981年 | 29篇 |
1980年 | 33篇 |
1979年 | 47篇 |
1978年 | 50篇 |
1977年 | 41篇 |
1975年 | 42篇 |
1974年 | 40篇 |
1973年 | 36篇 |
1971年 | 38篇 |
1966年 | 28篇 |
排序方式: 共有4953条查询结果,搜索用时 0 毫秒
91.
The COVID-19 pandemic has necessitated the rapid implementation of telemedical health services. In the United Kingdom, one service that has benefitted from this response is the provision of early medical abortion. England, Wales, and Scotland have all issued approval orders to this effect. These orders allow women to terminate pregnancies up to certain gestational limits, removing the need for them to contravene social distancing measures to access care. However, they are intended only as temporary measures for the duration of the pandemic response. In this paper, we chart these developments and further demonstrate the already acknowledged politicisation of abortion care. We focus on two key elements of the orders: (1) the addition of updated clinical guidance in the Scottish order that suggests an extended gestational limit, and (2) sunset clauses in the English and Welsh orders, as well as an indication of similar intentions in Scotland. In discussing these two issues, we suggest that the refusal of UK governments to introduce telemedical provision of early medical abortion previously has not been based on health concerns. Further, we question whether it would be appropriate for the approval orders to be lifted following the pandemic, suggesting that to do so would represent regressive and harmful policy. 相似文献
92.
93.
Marie T. Williams D.W. Parsons Elizabeth R. Ellis A.J. Martin S.E. Giles R.A. Frick 《Physiotherapy theory and practice》2013,29(2):57-67
Cystic fibrosis (CF) results in increased energy requirements at rest. However, the energy expended during physiotherapy management is unknown. The aim of this study, therefore, is to examine the energy expended during two commonly used forms of chest physiotherapy in CF subjects. Twenty-six CF subjects completed a randomised crossover trial with 48 hours between treatments. Two regimens of treatment were conducted: therapist-assisted treatment (active cycle of breathing, ACBT, with percussion, vibration), and independent treatment (ACBT alone, under the supervision of a physiotherapist). Subjects completed pulmonary function tests before and after either treatment. Indirect calorimetry and oximetry parameters were recorded at rest, during, and following treatment. Treatment groups were compared using ANOVA and two-sample crossover t-tests. When compared to resting values, physiotherapy treatment resulted in significant increases in VO2, VCO2 and respiratory exchange ratio. No difference was evident between treatment regimens for the change in VO2 between baseline and treatment. The increase in ventilation (baseline to treatment) was significantly greater for the therapist-assisted treatment. The therapist-assisted ACBT was associated with a significant carryover effect for forced expiratory flow at 50% of vital capacity (FEF50). Oxygen requirements for the two treatments were similar. However, the assisted regimen resulted in greater changes in minute ventilation during treatment and improved 48-hour post-treatment pulmonary function after only one treatment session. These findings suggest that the inclusion of percussion and vibration within the ACBT may influence respiratory muscle activity during treatment and result in improved pulmonary function. 相似文献
94.
95.
96.
The vegetation and geology of the Wet Tropics Bioregion of North Queensland, covering 1?998?150 ha, were mapped at a scale of 1:50?000. The resulting geographic information system (GIS) data base provided an unprecedented opportunity to examine vegetation condition across the entire bioregion. Mapping used colour aerial photography at 1:25?000, informed by ground truthing. Vegetation type, nature of the understory and ground cover, degree and type of disturbance, and the presence of secondary vegetation were described by a coding system, with codes marked directly on the aerial photos.Analysis of these data has confirmed a picture, which emerged from ground truthing, of large areas of sclerophyll woodland and forest being invaded by a rainforest understory that prevents regeneration of the sclerophyll canopy. Fifty-three per cent of the native vegetation of the bioregion consists of non-rainforest vegetation types, dominated in both area and number by sclerophyll woodlands and forests. Seventeen per cent of the 735?713 ha of sclerophyll woodland and forest types were assessed as having suffered irreversible change. Between 25% and 79% of individual forest vegetation types were judged to have been affected by irreversible change. No climatic changes, or changes in the environment, apart from those related to changing fire regimes, were identified as causative factors. Changed fire regimes, predominantly fire exclusion, are considered to be the most likely cause. 相似文献
97.
98.
Nikolas A. Jagodzinski Adrian Hughes Niel P. Davis Michael Butler Ian G. Winson Stephen W. Parsons 《Foot and Ankle Surgery》2013,19(2):125-130
BackgroundSymptomatic tarsal coalitions failing conservative treatment are traditionally managed by open resection. We describe an arthroscopic technique for excising talocalcaneal coalitions and present a retrospective two-surgeon case series of the first eight patients (nine feet).MethodsOutcome measures include restoration of subtalar movements, return to work and sports, visual analogue pain scales and Sports Athlete Foot and Ankle Scores (SAFAS). Follow-up ranges from 1 to 5.5 years.ResultsPain and SAFAS improved in 7 patients. Subtalar movements were improved in all feet. All patients achieved early good function but one relapsed requiring subsequent fusions. One posterior tibial nerve was damaged.ConclusionsMinimal destruction of bone and soft tissues allows early mobilization and minimizes pain. Patient selection and preoperative planning are crucial to avoid relapse and complication. This series from two independent surgeons supports the feasibility and effectiveness of this technique. 相似文献
99.
Houvast Ruben D. Baart Victor M. Bhairosingh Shadhvi S. Cordfunke Robert A. Chua Jia Xin Vankemmelbeke Mireille Parsons Tina Kuppen Peter J. K. Durrant Lindy G. Vahrmeijer Alexander L. Sier Cornelis F. M. 《Molecular imaging and biology》2020,22(6):1511-1522
Molecular Imaging and Biology - Aberrantly expressed glycans in cancer are of particular interest for tumor targeting. This proof-of-concept in vivo study aims to validate the use of aberrant Lewis... 相似文献
100.