全文获取类型
收费全文 | 351篇 |
免费 | 22篇 |
国内免费 | 2篇 |
出版年
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 16篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 16篇 |
2017年 | 9篇 |
2016年 | 21篇 |
2015年 | 35篇 |
2014年 | 22篇 |
2013年 | 23篇 |
2012年 | 26篇 |
2011年 | 21篇 |
2010年 | 9篇 |
2009年 | 10篇 |
2008年 | 18篇 |
2007年 | 13篇 |
2006年 | 21篇 |
2005年 | 20篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 3篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1962年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有375条查询结果,搜索用时 359 毫秒
121.
122.
Value-based requirements engineering plays a vital role in the development of value-based software (VBS). Stakeholders are the key players in the requirements engineering process, and the selection of critical stakeholders for the VBS systems is highly desirable. Based on the stakeholder requirements, the innovative or value-based idea is realized. The quality of the VBS system is associated with the concrete set of valuable requirements, and the valuable requirements can only be obtained if all the relevant valuable stakeholders participate in the requirements elicitation phase. The existing value-based approaches focus on the design of the VBS systems. However, the focus on the valuable stakeholders and requirements is inadequate. The current stakeholder identification and quantification (SIQ) approaches are neither state-of-the-art nor systematic for the VBS systems. The existing approaches are time-consuming, complex and inconsistent which makes the initiation process difficult. Moreover, the main motivation of this research is that the existing SIQ approaches do not provide the low level implementation details for SIQ initiation and stakeholder metrics for quantification. Hence, keeping in view the existing SIQ problems, this research contributes in the form of a new SIQ framework called ‘StakeMeter’. The StakeMeter framework is verified and validated through case studies. The proposed framework provides low-level implementation guidelines, attributes, metrics, quantification criteria and application procedure as compared to the other methods. The proposed framework solves the issues of stakeholder quantification or prioritization, higher time consumption, complexity, and process initiation. The framework helps in the selection of highly critical stakeholders for the VBS systems with less judgmental error. 相似文献
123.
Kunjan Patel Arnaud P. Giese J. M. Grossheim Rashima S. Hegde Maria Delio Joy Samanich Saima Riazuddin Gregory I. Frolenkov Jinlu Cai Zubair M. Ahmed Bernice E. Morrow 《PloS one》2015,10(10)
Hearing loss is a complex disorder caused by both genetic and environmental factors. Previously, mutations in CIB2 have been identified as a common cause of genetic hearing loss in Pakistani and Turkish populations. Here we report a novel (c.556C>T; p.(Arg186Trp)) transition mutation in the CIB2 gene identified through whole exome sequencing (WES) in a Caribbean Hispanic family with non-syndromic hearing loss. CIB2 belongs to the family of calcium-and integrin-binding (CIB) proteins. The carboxy-termini of CIB proteins are associated with calcium binding and intracellular signaling. The p.(Arg186Trp) mutation is localized within predicted type II PDZ binding ligand at the carboxy terminus. Our ex vivo studies revealed that the mutation did not alter the interactions of CIB2 with Whirlin, nor its targeting to the tips of hair cell stereocilia. However, we found that the mutation disrupts inhibition of ATP-induced Ca2+ responses by CIB2 in a heterologous expression system. Our findings support p.(Arg186Trp) mutation as a cause for hearing loss in this Hispanic family. In addition, it further highlights the necessity of the calcium binding property of CIB2 for normal hearing. 相似文献
124.
125.
Identification and functional characterization of natural human melanocortin 1 receptor mutant alleles in Pakistani population 下载免费PDF全文
Cecilia Herraiz Serrano Rizwan Yousaf Celia Jiménez‐Cervantes Sairah Yousaf Yar M. Waryah Haseeb A. Dad Elizabeth M. Blue Nara Sobreira Francesc López‐Giráldez Tasleem Kausar Muhammad Ali Ali M. Waryah Saima Riazuddin Rehan S. Shaikh Zubair M. Ahmed 《Pigment cell & melanoma research》2015,28(6):730-735
Melanocortin 1 receptor (MC1R), a Gs protein‐coupled receptor of the melanocyte's plasma membrane, is a major determinant of skin pigmentation and phototype. Upon activation by α‐melanocyte stimulating hormone, MC1R triggers the cAMP cascade to stimulate eumelanogenesis. We used whole‐exome sequencing to identify causative alleles in Pakistani families with skin and hair hypopigmentation. Six MC1R mutations segregated with the phenotype in seven families, including a p.Val174del in‐frame deletion and a p.Tyr298* nonsense mutation, that were analyzed for function in heterologous HEK293 cells. p.Tyr298* MC1R showed no agonist‐induced signaling to the cAMP or ERK pathways, nor detectable agonist binding. Conversely, signaling was comparable for p.Val174del and wild‐type in HEK cells overexpressing the proteins, but binding analysis suggested impaired cell surface expression. Flow cytometry and confocal imaging studies revealed reduced plasma membrane expression of p.Val174del and p.Tyr298*. Therefore, p.Tyr298* was a total loss‐of‐function (LOF) allele, while p.Val174del displayed a partial LOF attribute. 相似文献
126.
Shokit Hussain Shaeel Ahmed Al-Thabaiti Zaheer Khan 《Bioprocess and biosystems engineering》2014,37(9):1727-1735
A simple one-spot synthetic route for the production of Ag-nanoparticles using aqueous extract of citrus lemon is being reported in presence of shape-directing cetyltrimethylammonium bromide (CTAB). To our knowledge, this is the first report where the biomolecules form a layer around a group of the Ag-nanoparticles in which the inner layer is bound to the AgNPs surface via the hydroxyl groups of citric acid. The appearance of a sharp surface plasmon resonance band in the UV–visible region might be due to the formation of spherical Ag-nanoparticles. Agglomeration number (N Ag), the average number of silver atoms per nanoparticle (N), molar concentrations of nanoparticle (C) in solution, extinction coefficient (ε) and increase in the Fermi energy (ΔE F) were calculated using Mie theory and discussed. Interestingly, reaction mixture became turbid at higher [CTAB] due to the uncontrolled growth of Ag-nanoparticles. The transmission electron microscopic images of nanoparticles, recorded at different magnifications. 相似文献
127.
Nazir Mamona Saleem Muhammad Ali Iftikhar Abbas Ghulam Rehman Najeeb Ur Green Ivan R. Hussain Wahid Khan Saima Hussain Hidayat 《Phytochemistry Reviews》2021,20(1):119-143
Phytochemistry Reviews - In the last decade the prevalence of diabetes has escalated globally and it is estimated that the number of diabetic people will increase to 642 million by 2040. Although... 相似文献
128.
129.
Cochemé HM Quin C McQuaker SJ Cabreiro F Logan A Prime TA Abakumova I Patel JV Fearnley IM James AM Porteous CM Smith RA Saeed S Carré JE Singer M Gems D Hartley RC Partridge L Murphy MP 《Cell metabolism》2011,13(3):340-350
Hydrogen peroxide (H(2)O(2)) is central to mitochondrial oxidative damage and redox signaling, but its roles are poorly understood due to the difficulty of measuring mitochondrial H(2)O(2) in vivo. Here we report a ratiometric mass spectrometry probe approach to assess mitochondrial matrix H(2)O(2) levels in vivo. The probe, MitoB, comprises a triphenylphosphonium (TPP) cation driving its accumulation within mitochondria, conjugated to an arylboronic acid that reacts with H(2)O(2) to form a phenol, MitoP. Quantifying the MitoP/MitoB ratio by liquid chromatography-tandem mass spectrometry enabled measurement of a weighted average of mitochondrial H(2)O(2) that predominantly reports on thoracic muscle mitochondria within living flies. There was an increase in mitochondrial H(2)O(2) with age in flies, which was not coordinately altered by interventions that modulated life span. Our findings provide approaches to investigate mitochondrial ROS in vivo and suggest that while an increase in overall mitochondrial H(2)O(2) correlates with aging, it may not be causative. 相似文献
130.
Stéphane Compant Saima Muzammil Ahmed Lebrihi Florence Mathieu 《Plant and Soil》2013,370(1-2):583-591