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81.
Hugues Fouotsa Alain Meli Lannang Celine Djama Mbazoa Saima Rasheed Bishnu P. Marasini Zulfiqar Ali Krishna Prasad Devkota Augustin Ephrem Kengfack Farzana Shaheen Muhammad Iqbal Choudhary Norbert Sewald 《Phytochemistry letters》2012,5(2):236-239
One new xanthone, caroxanthone (1) together with six known xanthones, 4-prenyl-2-(3,7-dimethyl-2,6-octadienyl)-1,3,5,8-tetrahydroxyxanthone (2), smeathxanthone A (3), gartanin (4), euxanthone (5), 8-hydroxycudraxanthone G (6) and morusignin I (7) were isolated from the stem bark of Garcinia nobilis. The structures were determined by 1D- and 2D-NMR techniques. All these compounds were tested for anti-glycation, α-glucosidase and α-chymotrypsin activities. Some of them exhibited strong to moderate α-glucosidase activities, while none of them inhibited α-chymotrypsin. Compounds 6 and 7 were found to be modest α-glucosidase inhibitors with IC50 values of 76 μM and 84 μM, respectively. 相似文献
82.
Rekha Gautam Bhagawat Chandrasekar Mukta Deobagkar-Lele Srabanti Rakshit Vinay Kumar B. N. Siva Umapathy Dipankar Nandi 《PloS one》2012,7(9)
Acetaminophen is a widely prescribed drug used to relieve pain and fever; however, it is a leading cause of drug-induced liver injury and a burden on public healthcare. In this study, hepatotoxicity in mice post oral dosing of acetaminophen was investigated using liver and sera samples with Fourier Transform Infrared microspectroscopy. The infrared spectra of acetaminophen treated livers in BALB/c mice show decrease in glycogen, increase in amounts of cholesteryl esters and DNA respectively. Rescue experiments using L-methionine demonstrate that depletion in glycogen and increase in DNA are abrogated with pre-treatment, but not post-treatment, with L-methionine. This indicates that changes in glycogen and DNA are more sensitive to the rapid depletion of glutathione. Importantly, analysis of sera identified lowering of glycogen and increase in DNA and chlolesteryl esters earlier than increase in alanine aminotransferase, which is routinely used to diagnose liver damage. In addition, these changes are also observed in C57BL/6 and Nos2
−/− mice. There is no difference in the kinetics of expression of these three molecules in both strains of mice, the extent of damage is similar and corroborated with ALT and histological analysis. Quantification of cytokines in sera showed increase upon APAP treatment. Although the levels of Tnfα and Ifnγ in sera are not significantly affected, Nos2
−/− mice display lower Il6 but higher Il10 levels during this acute model of hepatotoxicity. Overall, this study reinforces the growing potential of Fourier Transform Infrared microspectroscopy as a fast, highly sensitive and label-free technique for non-invasive diagnosis of liver damage. The combination of Fourier Transform Infrared microspectroscopy and cytokine analysis is a powerful tool to identify multiple biomarkers, understand differential host responses and evaluate therapeutic regimens during liver damage and, possibly, other diseases. 相似文献
83.
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
84.
85.
Identification and functional characterization of natural human melanocortin 1 receptor mutant alleles in Pakistani population
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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
86.
Mukta Chakraborty Erich D. Jarvis 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1684)
Understanding the mechanisms of evolution of brain pathways for complex behaviours is still in its infancy. Making further advances requires a deeper understanding of brain homologies, novelties and analogies. It also requires an understanding of how adaptive genetic modifications lead to restructuring of the brain. Recent advances in genomic and molecular biology techniques applied to brain research have provided exciting insights into how complex behaviours are shaped by selection of novel brain pathways and functions of the nervous system. Here, we review and further develop some insights to a new hypothesis on one mechanism that may contribute to nervous system evolution, in particular by brain pathway duplication. Like gene duplication, we propose that whole brain pathways can duplicate and the duplicated pathway diverge to take on new functions. We suggest that one mechanism of brain pathway duplication could be through gene duplication, although other mechanisms are possible. We focus on brain pathways for vocal learning and spoken language in song-learning birds and humans as example systems. This view presents a new framework for future research in our understanding of brain evolution and novel behavioural traits. 相似文献
87.
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
88.
89.
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
90.
Stéphane Compant Saima Muzammil Ahmed Lebrihi Florence Mathieu 《Plant and Soil》2013,370(1-2):583-591