全文获取类型
收费全文 | 198篇 |
免费 | 11篇 |
专业分类
209篇 |
出版年
2022年 | 7篇 |
2021年 | 10篇 |
2020年 | 3篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 10篇 |
2015年 | 23篇 |
2014年 | 13篇 |
2013年 | 17篇 |
2012年 | 20篇 |
2011年 | 13篇 |
2010年 | 6篇 |
2009年 | 8篇 |
2008年 | 9篇 |
2007年 | 10篇 |
2006年 | 12篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1975年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有209条查询结果,搜索用时 0 毫秒
51.
Angoh Siow Yan Jennifer Freeland Joanna Paterson James Rupasinghe Prabha Amali Davy Christina M. 《Biological invasions》2021,23(7):2271-2288
Biological Invasions - Invasive species can significantly impact native wildlife by structurally altering habitats and access to resources. Understanding how native species respond to habitat... 相似文献
52.
Joyce M Ngoi Peter K Quashie Collins M Morang'a Joseph HK Bonney Dominic SY Amuzu Selassie Kumordjie Ivy A Asante Evelyn Y Bonney Miriam Eshun Linda Boatemaa Vanessa Magnusen Erasmus N Kotey Nicaise T Ndam Frederick Tei-Maya Augustina K Arjarquah Evangeline Obodai Isaac D Otchere Yaw Bediako Joe K Mutungi Lucas N Amenga-Etego John K Odoom Abraham K Anang George B Kyei Bright Adu William K Ampofo Gordon A Awandare 《Experimental biology and medicine (Maywood, N.J.)》2021,246(8):960
The confirmed case fatality rate for the coronavirus disease 2019 (COVID-19) in Ghana has dropped from a peak of 2% in March to be consistently below 1% since May 2020. Globally, case fatality rates have been linked to the strains/clades of circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within a specific country. Here we present 46 whole genomes of SARS-CoV-2 circulating in Ghana, from two separate sequencing batches: 15 isolates from the early epidemic (March 12–April 1 2020) and 31 from later time-points ( 25–27 May 2020). Sequencing was carried out on an Illumina MiSeq system following an amplicon-based enrichment for SARS-CoV-2 cDNA. After genome assembly and quality control processes, phylogenetic analysis showed that the first batch of 15 genomes clustered into five clades: 19A, 19B, 20A, 20B, and 20C, whereas the second batch of 31 genomes clustered to only three clades 19B, 20A, and 20B. The imported cases (6/46) mapped to circulating viruses in their countries of origin, namely, India, Hungary, Norway, the United Kingdom, and the United States of America. All genomes mapped to the original Wuhan strain with high similarity (99.5–99.8%). All imported strains mapped to the European superclade A, whereas 5/9 locally infected individuals harbored the B4 clade, from the East Asian superclade B. Ghana appears to have 19B and 20B as the two largest circulating clades based on our sequence analyses. In line with global reports, the D614G linked viruses seem to be predominating. Comparison of Ghanaian SARS-CoV-2 genomes with global genomes indicates that Ghanaian strains have not diverged significantly from circulating strains commonly imported into Africa. The low level of diversity in our genomes may indicate lower levels of transmission, even for D614G viruses, which is consistent with the relatively low levels of infection reported in Ghana. 相似文献
53.
Yaw Ampem Amoako Nancy Ackam John-Paul Omuojine Michael Ntiamoah Oppong Abena Gyawu Owusu-Ansah Mohammed Kabiru Abass George Amofa Elizabeth Ofori Michael Frimpong Freddie Bailey David Hurst Molyneux Richard Odame Phillips 《PLoS neglected tropical diseases》2021,15(6)
BackgroundBuruli ulcer disease (BUD) results in disabilities and deformities in the absence of early medical intervention. The extensive role of caregiving in BUD is widely acknowledged, however, associated caregiver burden is poorly understood. In this paper we assessed the burden which caregivers experience when supporting patients with BUD in Ghana.Method/ principal findingsThis qualitative study was conducted in 3 districts in Ghana between August and October 2019. 13 semi-structured interviews were conducted on caregivers of BUD patients in the local language of Twi. Data was translated into English, coded into broad themes, and direct content analysis approach was used to analyse results. The results show the caregivers face financial, psychological and health issues as a consequence of their caregiving role.Conclusion/ significanceThis study found significant caregiver burden on family members. It also highlighted the psychological burden caregivers experience and the limited knowledge of the disease within endemic communities. Further research is needed to quantify the caregiver burden of BUD at different economic levels in order to better understand the impact of possible caregiver interventions on patient outcomes. 相似文献
54.
Ce Zhang Armando Hernandez-Garcia Kai Jiang Zongying Gong Durgarao Guttula Siow Yee Ng Piravi P. Malar Jeroen A. van Kan Liang Dai Patrick S. Doyle Renko de Vries Johan R. C. van der Maarel 《Nucleic acids research》2013,41(20):e189
The effect of a cationic-neutral diblock polypeptide on the conformation of single DNA molecules confined in rectangular nanochannels is investigated with fluorescence microscopy. An enhanced stretch along the channel is observed with increased binding of the cationic block of the polypeptide to DNA. A maximum stretch of 85% of the contour length can be achieved inside a channel with a cross-sectional diameter of 200 nm and at a 2-fold excess of polypeptide with respect to DNA charge. With site-specific fluorescence labelling, it is demonstrated that this maximum stretch is sufficient to map large-scale genomic organization. Monte Carlo computer simulation shows that the amplification of the stretch inside the nanochannels is owing to an increase in bending rigidity and thickness of bottlebrush-coated DNA. The persistence lengths and widths deduced from the nanochannel data agree with what has been estimated from the analysis of atomic force microscopy images of dried complexes on silica. 相似文献
55.
56.
Minnullina Leyla Kostennikova Zarina Evtugin Vladimir Akosah Yaw Sharipova Margarita Mardanova Ayslu 《International microbiology》2022,25(1):111-122
International Microbiology - In current times, the opportunistic pathogen Morganella morganii is increasingly becoming a cause of urinary tract infections. The condition has been further... 相似文献
57.
Victor Max Corman Adam Grundhoff Christine Baechlein Nicole Fischer Anatoly Gmyl Robert Wollny Dickson Dei Daniel Ritz Tabea Binger Ernest Adankwah Kwadwo Sarfo Marfo Lawrence Annison Augustina Annan Yaw Adu-Sarkodie Samuel Oppong Paul Becher Christian Drosten Jan Felix Drexler 《Journal of virology》2015,89(11):5876-5882
58.
Rebecca Lim Marcus J. Zavou Phillipa-Louise Milton Siow Teng Chan Jean L. Tan Hayley Dickinson Sean V. Murphy Graham Jenkin Euan M. Wallace 《Journal of visualized experiments : JoVE》2014,(90)
Respiratory dysfunction is one of the leading causes of morbidity and mortality in the world and the rates of mortality continue to rise. Quantitative assessment of lung function in rodent models is an important tool in the development of future therapies. Commonly used techniques for assessing respiratory function including invasive plethysmography and forced oscillation. While these techniques provide valuable information, data collection can be fraught with artefacts and experimental variability due to the need for anesthesia and/or invasive instrumentation of the animal. In contrast, unrestrained whole-body plethysmography (UWBP) offers a precise, non-invasive, quantitative way by which to analyze respiratory parameters. This technique avoids the use of anesthesia and restraints, which is common to traditional plethysmography techniques. This video will demonstrate the UWBP procedure including the equipment set up, calibration and lung function recording. It will explain how to analyze the collected data, as well as identify experimental outliers and artefacts that results from animal movement. The respiratory parameters obtained using this technique include tidal volume, minute volume, inspiratory duty cycle, inspiratory flow rate and the ratio of inspiration time to expiration time. UWBP does not rely on specialized skills and is inexpensive to perform. A key feature of UWBP, and most appealing to potential users, is the ability to perform repeated measures of lung function on the same animal. 相似文献
59.
Douglas Goh Tianxun Gong U. S. Dinish Kaustabh Kumar Maiti Chit Yaw Fu Ken-Tye Yong Malini Olivo 《Plasmonics (Norwell, Mass.)》2012,7(4):595-601
Gold nanorods (GNR) are synthesized using cetylmethylammonium bromide (CTAB) surfactants which function as structure-directing agents. However, CTAB forms a tightly bound cationic bilayer on GNR surface with the cationic trimethylammonium head group exposed to the aqueous media, which is known to be highly toxic in vitro and in vivo. Pluronic is a non-ionic triblock polymer, which can associate with CTAB and form stable CTAB?Cpolymer complexes due to hydrophobic interactions. In this work, two types of Pluronic triblock copolymers were used to encapsulate GNR to reduce their cytotoxicity and improve colloidal and optical stability for biological applications. These formulations were characterized by UV?Cvis absorption spectra analysis, transmission electron microscopy, cell viability studies, differential interference contrast microscopy and dark-field imaging. 相似文献
60.