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211.
212.
Martha Guevara-Cruz Chao-Qiang Lai Kris Richardson Laurence D. Parnell Yu-Chi Lee Armando R. Tovar Jose M. Ordovás Nimbe Torres 《Gene》2013
Background
Although dietary treatments can successfully reduce blood lipids in hypercholesterolemic subjects, individual variation in that response has on occasion been linked to allelic differences. SNP rs12449157 has shown association with HDL-C concentrations in GWAS and falls in the glucose-fructose oxidoreductase domain containing 2 (GFOD2) locus. Of interest, previous data suggest that this SNP may be under environmentally driven selection. Thus, the aim of this study was to assess if rs12449157 may mediate the response of lipid traits to a dietary supplementation (DS) with soy protein and soluble fiber in a Mexican population with hypercholesterolemia.Methods
Forty-one subjects with hypercholesterolemia were given a low saturated fat diet (LSFD) for 1 month, followed by a LSFD + DS that included 25 g of soy protein and 15 g of soluble fiber (S/SF) daily for 2 months. Anthropometric, clinical, biochemical and dietary variables were determined. We analyzed the gene–diet interaction between the GFOD2 genotype, with the minor allele frequency of 0.24, and the DS on total cholesterol (TC) and LDL-C concentrations.Results
Hypercholesterolemic subjects with GFOD2 rs12449157 G allele had higher serum TC and LDL-C at the baseline and showed a greater response to the LSCD + S/SF (− 83.9 and − 57.5 mg/dl, respectively) than those with GFOD2 AA genotype (− 40.1 and − 21.8 mg/dl, respectively) (P = 0.006 for TC, 0.025 for LDL-C, respectively).Conclusion
The observed differences in allele-driven, diet-induced changes in blood lipids may be the result of a recent environmentally driven selection on the rs12449157 minor allele. Variation in the GFOD2 gene contributes to the genetic basis for a differential response to a cholesterol- or lipid-lowering diet. 相似文献213.
On the front line: integrated habitat mapping for olive ridley sea turtles in the southeast Atlantic
214.
K. E. Parnell 《Coral reefs (Online)》1986,5(1):1-6
A technique to examine through reef water movement by direct tracing using fluorescent dyes is described. Results from an experiment conducted on the sand dominated fringing reef flat at Pioneer Bay, Orpheus Island, North Queensland, indicate net seaward water movement velocities in the order of 40 m day-1, and considerable vertical mixing. A conceptual model of water movement is proposed in which dispersive type water movement is predominant when the reef flat is submerged, with advection being more significant when the reef flat is exposed. The application of the method to the study of the mechanisms of diagenesis is discussed and water quality rather than water agitation is suggested as being the principal reason for most rapid lithification being reported as occurring near the sediment water interface. 相似文献
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Keith A. Grimaldi Ben van Ommen Jose M. Ordovas Laurence D. Parnell John C. Mathers Igor Bendik Lorraine Brennan Carlos Celis-Morales Elisa Cirillo Hannelore Daniel Brenda de Kok Ahmed El-Sohemy Susan J. Fairweather-Tait Rosalind Fallaize Michael Fenech Lynnette R. Ferguson Eileen R. Gibney Mike Gibney Ingrid M. F. Gjelstad Jim Kaput Anette S. Karlsen Silvia Kolossa Julie Lovegrove Anna L. Macready Cyril F. M. Marsaux J. Alfredo Martinez Fermin Milagro Santiago Navas-Carretero Helen M. Roche Wim H. M. Saris Iwona Traczyk Henk van Kranen Lars Verschuren Fabio Virgili Peter Weber Jildau Bouwman 《Genes & nutrition》2017,12(1):35
Nutrigenetic research examines the effects of inter-individual differences in genotype on responses to nutrients and other food components, in the context of health and of nutrient requirements. A practical application of nutrigenetics is the use of personal genetic information to guide recommendations for dietary choices that are more efficacious at the individual or genetic subgroup level relative to generic dietary advice. Nutrigenetics is unregulated, with no defined standards, beyond some commercially adopted codes of practice. Only a few official nutrition-related professional bodies have embraced the subject, and, consequently, there is a lack of educational resources or guidance for implementation of the outcomes of nutrigenetic research. To avoid misuse and to protect the public, personalised nutrigenetic advice and information should be based on clear evidence of validity grounded in a careful and defensible interpretation of outcomes from nutrigenetic research studies. Evidence requirements are clearly stated and assessed within the context of state-of-the-art ‘evidence-based nutrition’. We have developed and present here a draft framework that can be used to assess the strength of the evidence for scientific validity of nutrigenetic knowledge and whether ‘actionable’. In addition, we propose that this framework be used as the basis for developing transparent and scientifically sound advice to the public based on nutrigenetic tests. We feel that although this area is still in its infancy, minimal guidelines are required. Though these guidelines are based on semi-quantitative data, they should stimulate debate on their utility. This framework will be revised biennially, as knowledge on the subject increases. 相似文献
217.
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219.
Weinger JS Parnell KM Dorner S Green R Strobel SA 《Nature structural & molecular biology》2004,11(11):1101-1106
The ribosome accelerates the rate of peptide bond formation by at least 10(7)-fold, but the catalytic mechanism remains controversial. Here we report evidence that a functional group on one of the tRNA substrates plays an essential catalytic role in the reaction. Substitution of the P-site tRNA A76 2' OH with 2' H or 2' F results in at least a 10(6)-fold reduction in the rate of peptide bond formation, but does not affect binding of the modified substrates. Such substrate-assisted catalysis is relatively uncommon among modern protein enzymes, but it is a property predicted to be essential for the evolution of enzymatic function. These results suggest that substrate assistance has been retained as a catalytic strategy during the evolution of the prebiotic peptidyl transferase center into the modern ribosome. 相似文献
220.
Suzanne A. Eccles Deirdre P. McIntosh Helen P. Purvies Alan J. Cumber Geoffrey D. Parnell J. Anthony Forrester Jennifer M. Styles Christopher J. Dean 《Cancer immunology, immunotherapy : CII》1987,24(1):37-41
Summary An immunotoxin comprising a tumour-specific monoclonal antibody (11/160) coupled to ricin A chain, although inactive in in vitro cytotoxicity assays against HSNtc sarcoma target cells, was found to be capable of significant tumouricidal activity in syngeneic rats if potentiated by ricin B chain. The 11/160-ricin A, when bound to tumour cells prior to their inoculation, led to a slight inhibition of tumour growth s. c. compared with untreated sarcoma cells or those coated with antibody alone. However, all tumours in these groups developed progressively (69/69), whereas in those rats receiving 15 g or 150 g ricin B chain i. v. 5 min after tumour cell inoculation, the take rate was reduced to 75% and 30% respectively, and significantly longer latent periods were evident for those tumours which did develop. Ricin B chain similarly inhibited, in a dose-dependent manner, the lung colonisation potential of 11/160-ricin A coated HSNtc cells. No effects were obtained if the B chain treatment followed inoculation of untreated or antibody-coated cells, suggesting that systemically administered B chain is capable of gaining access to and activating antibody-ricin A chain conjugates bound to the surface of syngeneic sarcoma cells in lung or subcutaneous sites. Tumour inhibition was obtained in some instances with intervals of up to 24 h between inoculation of conjugate-coated tumour cells and B chain. Experiments are in progress to determine if such potentiation may be feasible in a therapeutic rather than a prophylactic setting using this syngeneic solid tumour system. 相似文献