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991.
992.
Color provides a reliable cue for object detection and identification during various behaviors such as foraging, mate choice, predator avoidance and navigation. The total number of colors that a visual system can discriminate is largely dependent on the number of different spectral types of cone opsins present in the retina and the spectral separations among them. Thus, opsins provide an excellent model system to study evolutionary interconnections at the genetic, phenotypic and behavioral levels. Primates have evolved a unique ability for three-dimensional color vision (trichromacy) from the two-dimensional color vision (dichromacy) present in the majority of other mammals. This was accomplished via allelic differentiation (e.g. most New World monkeys) or gene duplication (e.g. Old World primates) of the middle to long-wavelength sensitive (M/LWS, or red–green) opsin gene. However, questions remain regarding the behavioral adaptations of primate trichromacy. Allelic differentiation of the M/LWS opsins results in extensive color vision variability in New World monkeys, where trichromats and dichromats are found in the same breeding population, enabling us to directly compare visual performances among different color vision phenotypes. Thus, New World monkeys can serve as an excellent model to understand and evaluate the adaptive significance of primate trichromacy in a behavioral context. I shall summarize recent findings on color vision evolution in primates and introduce our genetic and behavioral study of vision-behavior interrelationships in free-ranging sympatric capuchin and spider monkey populations in Costa Rica.  相似文献   
993.
In the present study, seven galacturonosyltransferase-like (GATL) genes (OsGATLs) in rice (Oryza sativa L.) were genome-widely identified and the chromosomal locations and the gene structures of which were characterized. Under normal condition, OsGATL2 and OsGATL3 are highly expressed in root, while OsGATL4 is highly expressed in stem and leaf. Many cis-elements related to stress response and plant hormone were found in the promoter sequence of each OsGATL. The expression patterns of these OsGATL genes under treatment with abscisic acid (ABA), drought and low temperature were assessed by qRT-PCR. The expression levels of most OsGATLs significantly increased following the treatments with drought or low temperature. In addition, physicochemical properties of OsGATLs and phylogenetic analysis with GATL from rice and several other species were performed. 3D structures and protein–protein interaction (PPI) network of OsGATLs were further predicted by Swiss-model and STRING 9.0 database, respectively. The identification and bioinformatic analysis of GATL family in rice could provide reference data for further study on their biological functions, especially in the responsiveness to hormones and stress signaling.  相似文献   
994.
Apolipoprotein C3 (ApoC3) plays a regulatory role in triglyceride (TG) metabolism. The higher level of TG can be a cause in pathogenesis of the vascular diseases or metabolic syndrome (MetS). In this study, we examined the associations of ApoC3 polymorphisms (?482C>T rs2854117 and 3238G>C rs5128) with Korean MetS patients. A total of 835 subjects were investigated, including 320 patients with MetS and 515 healthy subjects. The genotype analysis of the ApoC3 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism methods. Of the two polymorphisms studied, we observed a significant difference in the ?482C>T polymorphism between the MetS and control groups. The TT genotype of the ?482C>T polymorphism was associated with increased risk for MetS, compared with the controls (OR 1.627, 95 % CI 1.075–2.463, P = 0.021). The association was female-specific. No associations were found for the risk of MetS in the 3238G>C polymorphism. Haplotypes composed of two polymorphisms, however, were associated with MetS susceptibility in only male group. The 3238G>C polymorphism was significantly associated with TG levels (P = 0.013). Our data suggest that the ApoC3 ?482C>T polymorphism is associated with increased MetS susceptibility in the Korean population.  相似文献   
995.
996.
Cannabidiol (CBD) is a major Cannabis sativa constituent, which does not cause the typical marijuana psychoactivity. However, it has been shown to be active in a numerous pharmacological assays, including mice tests for anxiety, obsessive-compulsive disorder, depression and schizophrenia. In human trials the doses of CBD needed to achieve effects in anxiety and schizophrenia are high. We report now the synthesis of 3 fluorinated CBD derivatives, one of which, 4''-F-CBD (HUF-101) (1), is considerably more potent than CBD in behavioral assays in mice predictive of anxiolytic, antidepressant, antipsychotic and anti-compulsive activity. Similar to CBD, the anti-compulsive effects of HUF-101 depend on cannabinoid receptors.  相似文献   
997.
A siphon is a device that is used to drain a container, with water rising inside a hose in the form of an inverted U and then going down towards a discharge point placed below the initial water level. The siphon is the first of a number of inventions of the ancients documented about 2.000 years ago by Hero of Alexandria in his treatise Pneumatics, and although the explanation given by Hero was essentially correct, there is nowadays a controversy about the underlying mechanism that explains the working of this device. Discussions concerning the physics of a siphon usually refer to concepts like absolute negative pressures, the strength of liquid’s cohesion and the possibility of a siphon working in vacuum or in the presence of bubbles. Torricelli understood the working principle of the barometer and the impossibility of pumping water out of wells deeper than 10.33 m. Following Torricelli’s ideas it would also not be possible to build a siphon that drives pure water to ascend higher than 10.33 m. In this work, we report the first siphon that drives water (with surfactant) to ascend higher than the Torricellian limit. Motivated by the rising of sap in trees, we built a 15.4 m siphon that shows that absolute negative pressures are not prohibited, that cohesion plays an important role in transmitting forces through a fluid, and that surfactants can help to the transport of water in a metastable regime of negative pressures.  相似文献   
998.
Betaine aldehyde dehydrogenase (BADH) is widely considered as a key enzyme in glycine betaine metabolism in higher plants. Several paralogous genes encoding different isozymes of BADH have been identified and characterized in some plants; however, until now, only limited information is available about BADH genes in quinoa (Chenopodium quinoa). Here, we report the molecular cloning, structural organization, phylogenetic evolution, and expression profile of a BADH gene (CqBADH1) from quinoa. The translated putative CqBADH1 protein included five conserved features of the ALDH Family 10. Comparisons between the cDNA and genomic sequences revealed that the CqBADH1 gene contained 15 exons and 14 introns. Comparative screening of introns in homologous genes demonstrated that the number and position of the BADH introns were highly conserved among the BADH genes in Amaranthaceae plants and in other more distantly related plant species. A phylogenetic analysis showed that CqBADH1 had the closest relationship with a protein from Atriplex canescens and belonged to the ALDH10 family. Expression profile analyses indicated that CqBADH1 was expressed only in root, and showed time-dependent expression profiles under NaCl-stress condition. Moreover, in quinoa, NaCl stress led to increased levels of CqBADH1 mRNA accompanied by the accumulation of glycine betaine. This is the first study to describe a BADH gene in quinoa.  相似文献   
999.
Chronic kidney disease (CKD) is characterized by a progressive loss of kidney function over a period of months or years. It is estimated that about 7.2 % of adults over the age of 30 have CKD worldwide. Although one of the major risk factors of CKD is family history, the heritability of CKD is not fully understood. It is also known that the diabetic condition is highly influential on the onset of CKD. To understand the genetic bases of CKD that remain unidentified, we performed genetic association analyses for kidney function-related traits such as blood urea nitrogen (BUN) and albumin in subjects stratified by diabetic status. In the discovery stage of the study, we used genome-wide scan data and clinical data in about 8800 subjects from the Korean Association Resource (KARE) project. Health2 study data comprising about 1800 subjects were used for the replication stage. Our two stage association analyses demonstrated that the LOC105374266 locus (rs9820070) showed strong evidence of association with BUN (P = 8.47 × 10?14) in nondiabetic normal subjects (n = ~4300). To extend our knowledge of the genetic determinants influencing kidney function, we also analyzed the association between kidney function-related traits and microRNA related variants. For this analysis, miRNA related SNPs were selected from KARE and Health2 cohort genotype data. Our study suggests the potential relevance of miRNA to the kidney function (miR-518b for BUN; miR-146a and miR-1295a for albumin) in Korean populations.  相似文献   
1000.
The genus Jatropha (Euphorbiaceae) contains species that are of significant economic and ornamental value. However, Jatropha breeding material is rather limited due to incomplete information regarding phylogenetic relationships among germplasm resources. Phylogenetic analyses were performed based on the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS), two chloroplast regions (trnL-F and rbcL), and the combined (ITS+trnL-F+rbcL) dataset among twenty-five specimens representing six key Jatropha species. Phylogenetic relationships of Jatropha were well resolved between subgenus Curcas and subgenus Jatropha, and demonstrated the intermediate position of section Polymorphae among sections of both subgenera. Jatropha curcas and J. integerrima demonstrated a close phylogenetic relationship. The molecular data agreed with the morphological classification that recognized J. multifida and J. podagrica in sec. Peltatae. The distinct intraspecific divergence that occurred in J. curcas could be attributed to restricted gene flow caused by geographical isolation and different ecological conditions. Phylograms produced with trnL-F and rbcL sequence data suggested slow rates of sequence divergence among Jatropha spp., while the ITS gene tree had good resolution suggesting high genetic variation of ITS among Jatropha species.  相似文献   
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