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101.
Dolores Bernardo Amelia Pérez Cabo Monique Novaes-Ledieu José Pardo Concepción García Mendoza 《International microbiology》2004,7(4):277-281
Fungicides to control mycopathogens of commercial Agaricus bisporus, a mushroom cultivated for human consumption, are a major field of study, since these chemicals are toxic to both the host and its fungal parasites. The fungicide Prochloraz-Mn, used at its LD50 for A. bisporus, partially inhibited protein biosynthesis in the vegetative mycelial cell walls of this mushroom and caused significant changes in cell-wall polysaccharide structure, as deduced by methylation analysis and gas liquid chromatography-mass spectrometry (GLC-MS). Furthermore, the aggregated mycelial walls showed distinct alterations in their overall chemical composition following the administration of Prochloraz-Mn at the LD50 and the LD50 x1000. As expected, GLC-MS studies indicated that the latter dose caused more appreciable differences in polysaccharide structure. The decrease in mushroom crop yields obtained from industrial cultures treated with Prochloraz-Mn to control V. fungicola infection depended on the dose of the fungicide employed, whereas fruit-body morphology was only slightly affected at the highest Prochloraz-Mn concentration used. 相似文献
102.
Three new dihydroxamic acids (HO(CH3)NCO-(CH2)2-CO-NH-(CH2)x-CON(CH3)OH where the x values are 4; 3 and 2, and the compounds are abbreviated as 2,4-DIHA, 2,3-DIHA and 2,2-DIHA), containing the peptide group in a certain position to one of the two functional groups and in different distances to the other one, were synthesized and their complexation with Fe(III), Mo(VI) and V(V) was studied by pH-potentiometric, spectrophotometric and in some cases by CV methods to evaluate the redox behaviour of the Fe(III) complexes and assess their potential biological activity as siderophore models. All these compounds are structural models for the natural siderophore, desferrioxamine B (DFB). The results were compared to those of the complexes of 2,5-DIHA having the same connecting chain structure and length as DFB has, and the effects of the length of the connecting chain on the co-ordination mode and on the stability of the complexes formed were evaluated.Very similar stability of the mono-chelated complexes formed with all these dihydroxamic acids was found. All the results obtained suggest that one dihydroxamic acid (even the 2,2-DIHA) is able to complete the four coordination sites of a MoO2 2+ core forming simple mononuclear complexes. Favoured monomeric structures of the bis-chelated complexes of these dihydroxamic acids are also suggested with V(V) having the smallest ionic radius among the three metal ions studied. In the case of iron(III), however, clear indication was obtained for the slightly different complexation behaviour of 2,2-DIHA. Namely, the formation of the mononuclear bis-chelated complex with this shortest ligand seems to have sufficient strain to induce the formation of bimetallic species such as [Fe(2,2-DIHA)2Fe)]2+. 相似文献
103.
104.
105.
Isaac Brito-Morales Jorge García Molinos David S. Schoeman Michael T. Burrows Elvira S. Poloczanska Christopher J. Brown Simon Ferrier Tom D. Harwood Carissa J. Klein Eve McDonald-Madden Pippa J. Moore John M. Pandolfi James E.M. Watson Amelia S. Wenger Anthony J. Richardson 《Trends in ecology & evolution》2018,33(6):441-457
106.
107.
Janire De-La-Torre Guillermo Quindós Cristina Marcos-Arias Xabier Marichalar-Mendia María Luisa Gainza Elena Eraso Amelia Acha-Sagredo José Manuel Aguirre-Urizar 《Revista iberoamericana de micología》2018,35(3):134-139
Background
Candida can be implicated in the pathology of chronic periodontitis.Aims
To analyze the oral Candida carriage in patients suffering from chronic periodontitis (CP) and its correlation with the severity of this condition.Methods
Microbiological samples were taken from 155 patients using the oral rinse (OR) technique and by using paper points in the periodontal pockets (GPP). These patients were divided into 3 groups: 89 patients without CP (control), 47 with moderate CP, and 19 with severe CP. Samples were cultured in a Candida chromogenic agar for Candida. Species were identified by microbiological and molecular methods.Results
Candida was isolated in the OR of 45 (50.6%), 21 (44.7%), and 11 (57.9%) patients, respectively, and in the GPP of 32 (36%), 14 (29.2%), and 10 (42.6%) patients from the control, moderate CP and severe CP groups, respectively. Candida was isolated more frequently and in a greater burden in OR than in GPP (p < 0.01). Candida albicans was the most prevalent species. GPP of patients with CP had poor fungal biodiversity (p < 0.01).Conclusions
Colonization by Candida was present in the samples of patients without CP, and with both moderate and severe CP. Nonetheless, patients with severe CP had a higher rate of Candida colonization, especially by C. albicans. 相似文献108.
Amelia A. Langston Cathryn S. Mellersh Cassandra L. Neal Kunal Ray Gregory M. Acland Mark Gibbs Gustavo D. Aguirre R.E.K. Fournier Elaine A. Ostrander 《Genomics》1997,46(3):317
We have constructed a collection of canine–rodent microcell hybrid cell lines by fusion of canine fibroblast microcell donors with immortalized rodent recipient cells. Characterization of the hybrid cell lines using a combination of fluorescencein situhybridization and PCR analysis of canine microsatellite repeat sequences allowed selection of a panel of hybrids in which most canine chromosomes are represented. Approximately 90% of genetic markers and genes that were tested could be assigned to 1 of 31 anonymous canine chromosome groups, based on common patterns of retention in the hybrid set. Many of these putative chromosome groups have now been validated by linkage analysis. This panel of cell lines provides a tool for development of genetic, physical, and comparative maps of the canine genome. 相似文献
109.
R Jory Brinkerhoff Amelia B Markeson Jason H Knouft Kenneth L Gage John A Montenieri 《Journal of vector ecology》2006,31(2):355-363
Behavioral, genetic, and immune variation within a host population may lead to aggregation of parasites whereby a small proportion of hosts harbor a majority of parasites. In situations where two or more parasite species infect the same host population there is the potential for interaction among parasites that could potentially influence patterns of aggregation through either competition or facilitation. We studied the occurrence and abundance patterns of two congeneric flea species on black-tailed prairie dog (Cynomys ludovicianus) hosts to test for interactions among parasite species. We live-trapped prairie dogs on ten sites in Boulder County, CO and collected their fleas. We found a non-random, positive association between the two flea species, Oropsylla hirsuta and O. tuberculata cynomuris; hosts with high loads of one flea species had high loads of the second species. This result suggests that there is no interspecific competition among fleas on prairie dog hosts. Host weight had a weak negative relationship to flea load and host sex did not influence flea load, though there were slight differences in flea prevalence and abundance between male and female C. ludovicianus. While genetic and behavioral variation among hosts may predispose certain individuals to infection, our results indicate apparent facilitation among flea species that may result from immune suppression or other flea-mediated factors. 相似文献
110.
Amelia Moore 《The journal of the Royal Anthropological Institute》2016,22(1):27-46
The Anthropocene is the scientific label given by earth scientists to the current epoch of unprecedented anthropogenic planetary change. The Anthropocene is also a political label designed to call attention to this change and evolving notions of agency and responsibility in contemporary life. This article critically explores what I call ‘the Anthropocene idea’ and the condition of ‘Anthropocene spaces’ through selected anthropological writing about recent planetary change and through analysis of current events in a specific ‘vulnerable’ location. By considering recent events in The Bahamas, I arrive at an orientation that I call simply Anthropocene anthropology. Rather than advocating for the creation of a new subfield of research, this mode of engagement offers an open‐ended conceptual framework for the critical examination of the Anthropocene idea as it influences the symbolic and material realities of contemporary Anthropocene spaces. 相似文献