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51.
Stroink T Ortiz MC Bult A Lingeman H de Jong GJ Underberg WJ 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,817(1):49-66
Peptides and proteins are gaining increasing attention in biosciences and, consequently, in analysis. This overview highlights the different approaches to couple on-line various separation techniques for the determination of proteins and peptides. The first section discusses the liquid chromatography (LC)-LC coupling, the second one reviews the on-line LC-capillary electrophoresis (CE) coupled systems and the third section summarizes the strategies for on-line CE-CE. The advantages, disadvantages, most relevant difficulties and particular systems for on-line coupling are discussed. Special attention is paid to the interface between the two dimensions. Applications are summarized in tables and a few typical examples are discussed. Many multidimensional separation methods are available, and it is demonstrated that peptide and protein mapping, or quantitation of proteins or peptides in various samples (aqueous solutions, cells, plasma) require different coupled systems. For mapping a semi-quantitative detection is often sufficient, while comprehensiveness is very important. For quantitation of a certain peptide or protein at a low concentration level a validated method should be used, while a heart-cut transport of the first dimension to the second one can offer sufficient selectivity. The combination with mass spectrometry as part of the total system is stressed and illustrated. 相似文献
52.
In 1979 Kwon Chung described two varieties of Sporothrix schenckii based on the thermotolerance of isolates from fixed cutaneous (35°C) and that of disseminated cutaneous forms (37°C) of sporotrichosis. Since we had not noted such a difference previously in a study of 100 cases of this disease (55% localized and 45% disseminated) wherein all the isolates grew at 37°C, we decided to repeat this work.Our results differ from those reported by Kwon Chung, since the isolates of both the fixed and disseminated forms of sporotrichosis grew at 37 and 38°C, even when we used inocula of 30 conidia (20–50) which according to Kwon Chung were needed to observe this difference. 相似文献
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54.
Rafael Guerrero-Preston Lynn R Goldman Priscilla Brebi-Mieville Carmen Ili-Gangas Cynthia LeBron Mireya Hernandez-Arroyo Frank R Witter Ben J Apelberg Marina Roystacher Andrew Jaffe Rolf U Halden David Sidransky 《Epigenetics》2010,5(6):539-546
Environmental exposures in utero may alter the epigenome, thus impacting chromosomal stability and gene expression. We hypothesized that in utero exposures to maternal smoking and perfluoroalkyl compounds (PFCs) are associated with global DNA hypomethylation in umbilical cord serum. Our objective was to determine if global DNA methylation could be used as a biomarker of in utero exposures to maternal smoking and PFCs. Using an ELISA-based method, global DNA methylation was quantified in umbilical cord serum from 30 newborns with high (>10 ng/ml, mean 123.8 ng/ml), low (range 1–10 ng/ml, mean 1.6 ng/ml) and very low (<1 ng/ml, mean 0.06 ng/ml) cord serum cotinine levels. Y chromosome analysis was performed to rule out maternal DNA cross-contamination. Cord serum global DNA methylation showed an inverse dose response to serum cotinine levels (p < 0.001). Global DNA methylation levels in cord blood were the lowest among newborns with smoking mothers (mean = 15.04%; 95% CI, 8.4, 21.7) when compared to babies of mothers who were second-hand smokers (21.1%; 95% CI, 16.6, 25.5) and non-smokers (mean = 29.2%; 95% CI, 20.1, 38.1). Global DNA methylation was inversely correlated with serum PFOA (r = -0.35, p = 0.06) but not PFOS levels. Serum Y chromosome analyses did not detect maternal DNA cross-contamination. This study supports the use of global DNA methylation status as a biomarker of in utero exposure to cigarette smoke and PFCs.Key words: epigenomics, umbilical cord serum, hypomethylation, cigarette smoke, perfluorooctane sulfonate, perfluorooctanoate, global DNA methylation 相似文献
55.
Dilia Martínez Méndez Rosaura Hernández Valles Primavera Alvarado Mireya Mendoza 《Revista iberoamericana de micología》2013,30(1):39-46
BackgroundIn 1984 the Venezuelan Work Groups in Mycology (VWGM) were created introducing an innovative approach to the study of the mycoses in Venezuela.AimTo study the occurrence of the mycoses in Venezuela.MethodsReview the reported cases of mycoses by the newsletter Boletín Informativo Las Micosis en Venezuela (VWGM) from 1984 to 2010.ResultsThe data collected showed 36,968 reported cases of superficial mycoses, 1,989 of deep systemic cases, and 822 of localized mycoses. Pityriasis dermatophytosis was the most common superficial infection, and paracoccidioidomycosis and histoplasmosis the most frequent deep systemic infection. Chromoblastomycosis was the most frequently diagnosed subcutaneous infection. The data provided showed the distribution by geographical area for each of the fungal infections studied, which may help to establish the endemic areas.DiscussionSuperficial mycosis is a public health problem due to its high morbidity and is probably responsible for some of the outbreaks in high-risk groups. Paracoccidioidomycosis and histoplasmosis were reported more often, which agrees with earlier reports prior to the formation of the VWGM. Cases of sporotrichosis and chromoblastomycosis in Venezuela can be considered unique due to the high number of cases. This study highlights the contribution of the VWGM to the behavior of the mycoses in Venezuela, its incidence, prevalence, and the recognition of these infections as a problem of public health importance. The VWGM should keep working in this endeavor, not only reporting new cases, but also unifying the clinical and epidemiological criteria, in order to properly monitor the evolving epidemiological changes reported in these types of infections. 相似文献
56.
Poor understanding of the spliceosomal mechanisms to select intronic 3' ends (3'ss) is a major obstacle to deciphering eukaryotic genomes. Here, we discern the rules for global 3'ss selection in yeast. We show that, in contrast to the uniformity of yeast splicing, the spliceosome uses all available 3'ss within a distance window from the intronic branch site (BS), and that in ~70% of all possible 3'ss this is likely to be mediated by pre-mRNA structures. Our results reveal that one of these RNA folds acts as an RNA thermosensor, modulating alternative splicing in response to heat shock by controlling alternate 3'ss availability. Thus, our data point to a deeper role for the pre-mRNA in the control of its own fate, and to a simple mechanism for some alternative splicing. 相似文献
57.
58.
Vip3C, a Novel Class of Vegetative Insecticidal Proteins from Bacillus thuringiensis 总被引:2,自引:0,他引:2
L Palma CS Hernández-Rodríguez M Maeztu P Hernández-Martínez I Ruiz de Escudero B Escriche D Muñoz J Van Rie J Ferré P Caballero 《Applied and environmental microbiology》2012,78(19):7163-7165
Three vip3 genes were identified in two Bacillus thuringiensis Spanish collections. Sequence analysis revealed a novel Vip3 protein class (Vip3C). Preliminary bioassays of larvae from 10 different lepidopteran species indicated that Vip3Ca3 caused more than 70% mortality in four species after 10 days at 4 μg/cm(2). 相似文献
59.
Russell A. Mittermeier Jörg U. Ganzhorn William R. Konstant Kenneth Glander Ian Tattersall Colin P. Groves Anthony B. Rylands Andreas Hapke Jonah Ratsimbazafy Mireya I. Mayor Edward E. Louis Jr. Yves Rumpler Christoph Schwitzer Rodin M. Rasoloarison 《International journal of primatology》2008,29(6):1607-1656
A basic understanding of the taxonomy, diversity, and distributions of primates is essential for their conservation. This
review of the status of the taxonomy of lemurs is based on a 5-d workshop entitled “Primate Taxonomy for the New Millennium,”
held at the Disney Institute, Orlando, Florida, in February 2000. The aim is not to present a taxonomic revision, but to review
our current understanding of the diversity and current and past ranges of lemurs and indicate where there is controversy,
discrepancy, or lack of knowledge. Our goal therefore is to provide a baseline for future taxonomic investigation, as well
as a clearer focus for research and conservation priorities. We here focus on the lemurs of Madagascar and recognize 5 families,
15 genera, and 99 species and subspecies. We list 39 species of lemurs described since 2000: 2 dwarf lemurs, Cheirogaleus; 11 mouse lemurs, Microcebus; a giant mouse lemur, Mirza; a bamboo lemur, Hapalemur; 17 sportive lemurs, Lepilemur; and 7 woolly lemurs, Avahi. Taxonomic revisions have resulted in the resurrection of a further 9 taxa. However, the figures do not represent the total
diversity of Malagasy lemurs because more new species are being identified via new field studies and accompanying genetic
research, and should be described in the near future. 相似文献
60.
Acanthamoeba castellanii Proteases are Capable of Degrading Iron‐Binding Proteins as a Possible Mechanism of Pathogenicity 下载免费PDF全文
Gerardo Ramírez‐Rico Moisés Martínez‐Castillo Mireya de la Garza Mineko Shibayama Jesús Serrano‐Luna 《The Journal of eukaryotic microbiology》2015,62(5):614-622
Acanthamoeba castellanii, a free‐living amoeba, is an amphizoic organism that can behave as an opportunistic pathogen, causing granulomatous amoebic encephalitis in immunocompromised patients or infecting immunocompetent individuals via cutaneous lesions, sinusoidal infections, or amoebic keratitis. Therefore, this amoeba could be in contact with different iron‐binding proteins, such as lactoferrin in tears and mucosa and transferrin and hemoglobin in blood. Iron is a vital and necessary element for host metabolism but also for parasite survival. Accordingly, parasites have developed iron uptake mechanisms, one of which is the utilization of proteases to degrade host iron‐binding proteins. In this work, we performed a partial biochemical characterization of A. castellanii proteases at different pHs and utilizing protease inhibitors with 10% sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and copolymerized with different iron‐binding proteins. We describe for the first time the presence of several cysteine proteases in a total A. castellanii crude extract and in conditioned culture medium precipitated with ethanol. These amoebic peptidases degraded human holo‐lactoferrin, holo‐transferrin, hemoglobin, and horse spleen ferritin; some of these proteases were substrate specific, and others degraded multiple substrates. These proteases could be considered virulence factors that promote iron acquisition from the host. 相似文献