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61.
The Myth of Male Superiority: Rise and Demise 总被引:1,自引:0,他引:1
A prolific literature exists concerning the origins and functions of the institutionalization of sex-role differences. However, persistent problems and sharply divergent views remain. This study attempts to circumvent the nature/nurture controversy by utilizing a holistic-evolutionary approach to the problem. The reviews of evidence from ethology, developmental psychology, and cross-cultural investigations lead to a social-exchange model involving differences in the elasticities of male and female labor contributions in social evolution. Assumptions about future technological progress lead to prediction of the demise of the myth of male supremacy. [sex differences in social evolution, ontogeny of human behavior] 相似文献
62.
Qian Ren Hilda H.T. Au Qing S. Wang Seonghoon Lee Eric Jan 《Nucleic acids research》2014,42(14):9366-9382
The dicistrovirus intergenic internal ribosome entry site (IGR IRES) directly recruits the ribosome and initiates translation using a non-AUG codon. A subset of IGR IRESs initiates translation in either of two overlapping open reading frames (ORFs), resulting in expression of the 0 frame viral structural polyprotein and an overlapping +1 frame ORFx. A U–G base pair adjacent to the anticodon-like pseudoknot of the IRES directs +1 frame translation. Here, we show that the U-G base pair is not absolutely required for +1 frame translation. Extensive mutagenesis demonstrates that 0 and +1 frame translation can be uncoupled. Ribonucleic acid (RNA) structural probing analyses reveal that the mutant IRESs adopt distinct conformations. Toeprinting analysis suggests that the reading frame is selected at a step downstream of ribosome assembly. We propose a model whereby the IRES adopts conformations to occlude the 0 frame aminoacyl-tRNA thereby allowing delivery of the +1 frame aminoacyl-tRNA to the A site to initiate translation of ORFx. This study provides a new paradigm for programmed recoding mechanisms that increase the coding capacity of a viral genome. 相似文献
63.
In vitro and in vivo characterization of an interleukin‐15 antagonist peptide by metabolic stability, 99mTc‐labeling,and biological activity assays 下载免费PDF全文
Yunier Rodríguez‐Álvarez Ania Cabrales‐Rico Alejandro Perera‐Pintado Anais Prats‐Capote Hilda E. Garay‐Pérez Osvaldo Reyes‐Acosta Erik Pérez‐García Araceli Chico‐Capote Alicia Santos‐Savio 《Journal of peptide science》2018,24(4-5)
Interleukin (IL)–15 is an inflammatory cytokine that constitutes a validated therapeutic target in some immunopathologies, including rheumatoid arthritis (RA). Previously, we identified an IL‐15 antagonist peptide named [K6T]P8, with potential therapeutic application in RA. In the current work, the metabolic stability of this peptide in synovial fluids from RA patients was studied. Moreover, [K6T]P8 peptide was labeled with 99mTc to investigate its stability in human plasma and its biodistribution pattern in healthy rats. The biological activity of [K6T]P8 peptide and its dimer was evaluated in CTLL‐2 cells, using 3 different additives to improve the solubility of these peptides. The half‐life of [K6T]P8 in human synovial fluid was 5.88 ± 1.73 minutes, and the major chemical modifications included peptide dimerization, cysteinylation, and methionine oxidation. Radiolabeling of [K6T]P8 with 99mTc showed a yield of approximately 99.8%. The 99mTc‐labeled peptide was stable in a 30‐fold molar excess of cysteine and in human plasma, displaying a low affinity to plasma proteins. Preliminary biodistribution studies in healthy Wistar rats suggested a slow elimination of the peptide through the renal and hepatic pathways. Although citric acid, sucrose, and Tween 80 enhanced the solubility of [K6T]P8 peptide and its dimer, only the sucrose did not interfere with the in vitro proliferation assay used to assess their biological activity. The results here presented, reinforce nonclinical characterization of the [K6T]P8 peptide, a potential agent for the treatment of RA and other diseases associated with IL‐15 overexpression. 相似文献
64.
Radioimmunoassays capable of detecting pseudouridine, N2-dimethylguanosine, and 7-methylguanosine at picomole levels were developed. The antibodies to the nucleoside-human serum albumin conjugates recognize the modified ribose linked to the ?-amino group of lysine. The relative serological activities of the different nucleosides in the pseudouridine anti-pseudouridine-human serum albumin reaction depend upon the presence of the ribose ?-aminocaproate moiety in the radiolabeled antigen and/or the competing unlabeled nucleoside. 相似文献
65.
66.
Two new species of Phyllonema (Rivulariaceae,Cyanobacteria) with an emendation of the genus 下载免费PDF全文
Laura González‐Resendiz Jeffrey R. Johansen Viviana Escobar‐Sánchez Claudia Segal‐Kischinevzky Luis F. Jiménez‐García Hilda León‐Tejera 《Journal of phycology》2018,54(5):638-652
Two untapered, heterocytous species were observed and collected from the intertidal and supratidal zones of the Mexican coastline of the Pacific Ocean near Oaxaca and from the Gulf of Mexico. These populations were highly similar in morphology to the freshwater taxon Petalonema incrustans in the Scytonemataceae. However, 16S rRNA sequence data and phylogenetic analysis indicated that they were sister taxa to the epiphyllic, Brazilian species Phyllonema aveceniicola in the Rivulariaceae, described from culture material. While genetic identity between the two new species was high, they differed significantly in morphology, 16S rRNA gene sequence identity, and sequence and structure of the 16S–23S ITS region. Their morphology differed markedly from the generitype of the previously monotypic Phyllonema, which has tapered, heteropolar, single‐false branched trichomes with very thin or absent sheath. The two new species, Phyllonema ansata and Phyllonema tangolundensis, described from both culture and environmental material, have untapered, isopolar, geminately false branched trichomes with thick, lamellated sheaths, differences so significant that the species would not be placed in Phyllonema without molecular corroboration. The morphological differences are so significant that a formal emendation of the genus is required. These taxa provide a challenge to algal taxonomy because the morphological differences are such that one would logically conclude that they represent different genera, but the phylogenetic evidence for including them all in the same genus is conclusive. This conclusion is counter to the current trend in algal taxonomy in which taxa with minor morphological differences have been repeatedly placed in separate genera based primarily upon DNA sequence evidence. 相似文献
67.
Hilda Amiripour Babak Delnavaz Hashemloian Azra Ataei Azimi 《Acta Physiologiae Plantarum》2016,38(10):246
Rocket (Eruca sativa L.) is a medicinal plant that belongs to the Brassicaceae family and was reported to be a tolerant plant under soil salinity as well as high genetic diversity among its varieties. Since morphological and physiological changes to sodium sulfate stress toward this plant have not been investigated yet, the present study was implemented to assess the response of rocket (Eruca sativa L.) varieties to sodium sulfate (Na2SO4) stress as well as the relationship among these traits. Two varieties of rocket plants, the Iranian and Italian ones, were subjected to four salinity (Na2SO4) treatments [0 (control), 15, 30 and 60 mM of Na2SO4 solution] and three growth stages (49, 65, and 74 days) in factorial experiment with completely randomized design and three replications were considered. Some morphologic traits such as grain yield were measured during the growth period. The results of the analysis of variances between the mentioned variables indicated a significant difference between the varieties in terms of K+, Na+, Na+/K+, leaf length, grain yield, organic and mineral matter. The results of correlation and regression of the amounts of K+ showed a linear relationship with the grain yield and its variations were not independent from the variations of grain yield. Eventually, it seems that the Italian variety was more tolerant and having better performance in comparison with the Iranian variety, in response to salt stress. 相似文献
68.
In this study the possible effects of two predicted climate change scenarios on soil water regime of Hungarian Calcic Chernozem
soils has been investigated. Soil profiles classified as Calcic Chernozem — in total 49 — were selected from the MARTHA soil
physical database that incorporates soil data at national scale. These profiles were subdivided into three groups (sandy loam,
loam and clayey loam) in accordance with their mechanical composition. Soil water retention curves were scaled separately
for each of the three textural groups, using similar media scaling in order to represent the variability of soil hydrophysical
data with one parameter, the scaling factor (SF). Reference soil profiles were chosen according to the cumulative distribution
function of the scaling factor, six for each textural group. Daily downscaled meteorological data from A2 and B2 climate scenarios
of the Hadley Centre (2070–2100) and data from a reference period (RF, 1961–1990) were used in this study to characterize
different climatic situations. Nine representative years were selected in case of all the three scenarios, using the cumulative
probability function of the annual precipitation sum. Scenario analyses were performed, validating the SWAP soil water balance
simulation model for the 18 reference soil profiles and 27 representative years in order to evaluate the expected changes
in soil water regime under different from the present (RF) climatic conditions (A2 and B2 scenarios). Our results show that
the scaling factor could be used as a climate sensitivity indicator of soil water regime. The large climate sensitivity of
the majority of Chernozem soil subtypes water regime has been proven. 相似文献
69.
Martin Akerman Hilda David-Eden Ron Y Pinter Yael Mandel-Gutfreund 《Genome biology》2009,10(3):R30-14
Alternative splicing is regulated by splicing factors that serve as positive or negative effectors, interacting with regulatory elements along exons and introns. Here we present a novel computational method for genome-wide mapping of splicing factor binding sites that considers both the genomic environment and the evolutionary conservation of the regulatory elements. The method was applied to study the regulation of different alternative splicing events, uncovering an interesting network of interactions among splicing factors. 相似文献
70.