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201.
Expression QTL mapping by integrating genome-wide gene expression and genotype data is a promising approach to identifying functional genetic variation, but is hampered by the large number of multiple comparisons inherent in such studies. A novel approach to addressing multiple testing problems in genome-wide family-based association studies is screening candidate markers using heritability or conditional power. We apply these methods in settings in which microarray gene expression data are used as phenotypes, screening for SNPs near the expressed genes. We perform association analyses for phenotypes using a univariate approach. We also perform simulations on trios with large numbers of causal SNPs to determine the optimal number of markers to use in a screen. We demonstrate that our family-based screening approach performs well in the analysis of integrative genomic datasets and that screening using either heritability or conditional power produces similar, though not identical, results. 相似文献
202.
203.
Alvarado-Vázquez MA R Foroughbakhch MA Guzmán- Lucio A Rocha-Estrada JL Hernández-Piñero ML Cárdenas-Ávila BM Soto-García 《Phyton》2015,84(1):70-79
Candelilla (Euphorbia antisiphylitica Zucc.) is a very important plant resource in the arid lands of Northern Mexico. This is because the wax content coating the stem has unique properties which have been useful for multiple applications in the food industry, electronics, cosmetics, etc. However, the intensive exploitation of this resource has caused a great decrease in the populations of this species making necessary to consider strategies for their conservation and sustainable use. One of the primary needs with regeneration purposes is to know their reproductive processes, particularly the biotic and/or abiotic factors that determine the viability and germination of seeds. The present study evaluated the (1) germination and seed viability in relation to the ripeness degree of the fruit at the time of collection, (2) weight of the seed (low, medium and high), and (3) storage time (1, 3, and 5 months). Fruits from four locations, two in the State of Coahuila (Las Coloradas and Candela) and two in the State of Nuevo Leon (Icamole 1 and Icamole 2), were collected. Three germination assays were carried out corresponding to each month of storage. Seed viability was determined by the tetrazolium test. The average weight of the candelilla seeds was 0.0029 ± 0.0010 g, with extreme average values of 0.0018 ± 0.0006 g at Las Coloradas and 0.0036 ± 0.0010 g in Icamole 2. Those seeds with heavier weight obtained from red fruits and with 1 month of storage showed the highest average percentage of viability (66.87 ± 24.19%). At the same time, seeds with around average weight, obtained from red fruits and five months of storage, showed the highest average germination percentage (50.00 ± 9.42%). 相似文献
204.
Background
Improvements in protein sequence annotation and an increase in the number of annotated protein databases has fueled development of an increasing number of software tools to predict secreted proteins. Six software programs capable of high throughput and employing a wide range of prediction methods, SignalP 3.0, SignalP 2.0, TargetP 1.01, PrediSi, Phobius, and ProtComp 6.0, are evaluated. 相似文献205.
Wanninger A Koop D Bromham L Noonan E Degnan BM 《Development genes and evolution》2005,215(10):509-518
Recent interpretations of developmental gene expression patterns propose that the last common metazoan ancestor was segmented,
although most animal phyla show no obvious signs of segmentation. Developmental studies of non-model system trochozoan taxa
may shed light on this hypothesis by assessing possible cryptic segmentation patterns. In this paper, we present the first
immunocytochemical data on the ontogeny of the nervous system and the musculature in the sipunculan Phascolion strombus. Myogenesis of the first anlagen of the body wall ring muscles occurs synchronously and not subsequently from anterior to
posterior as in segmented spiralian taxa (i.e. annelids). The number of ring muscles remains constant during the initial stages
of body axis elongation. In the anterior-posteriorly elongated larva, newly formed ring muscles originate along the entire
body axis between existing myocytes, indicating that repeated muscle bands do not form from a posterior growth zone. During
neurogenesis, the Phascolion larva expresses a non-metameric, paired, ventral nerve cord that fuses in the mid-body region in the late-stage elongated
larva. Contrary to other trochozoans, Phascolion lacks any larval serotonergic structures. However, two to three FMRFamide-positive cells are found in the apical organ. In
addition, late larvae show commissure-like neurones interconnecting the two ventral nerve cords, while early juveniles exhibit
a third, medially placed FMRFamidergic ventral nerve. Although we did not find any indications for cryptic segmentation, certain
neuro-developmental traits in Phascolion resemble the conditions found in polychaetes (including echiurans) and myzostomids and support a close relationship of Sipuncula
and Annelida. 相似文献
206.
Johnson KL Degnan KA Ross Walker J Ingram GC 《The Plant journal : for cell and molecular biology》2005,44(1):114-127
The specification of epidermal (L1) identity occurs early during plant embryogenesis. Here we show that, in Arabidopsis, AtDEK1 encodes a key component of the embryonic L1 cell-layer specification pathway. Loss of AtDEK1 function leads to early embryo lethality characterized by a severe loss of cell organization in the embryo proper and abnormal cell divisions within the suspensor. Markers for L1 identity, ACR4 and ATML1, are not expressed in homozygous mutant embryos. In order to clarify the function of AtDEK1 further, an RNAi knockdown approach was used. This allowed embryos to partially complete embryogenesis before losing AtDEK1 activity. Resulting seedlings showed a specific loss of epidermal cell identity within large portions of the cotyledons. In addition, meristem structure and function was systematically either reduced or entirely lost. AtDEK1 expression is not restricted to the L1 epidermal cell layer at any stage in development. This is consistent with AtDEK1 playing an upstream role in the continuous generation or interpretation of positional information required for epidermal specification. Our results not only identify a specific role for AtDEK1 during embryogenesis, but underline the potential key importance of L1 specification at the globular stage for subsequent progression through embryogenesis. 相似文献
207.
208.
Java language has been demonstrated to be an effective tool in supporting medical image viewing in Russia. This evaluation was completed by obtaining a maximum of 20 images, depending on the client's computer workstation from one patient using a commercially available computer tomography (CT) scanner. The images were compared against standard CT images that were viewed at the site of capture. There was no appreciable difference. The client side is a lightweight component that provides an intuitive interface for end users. Each image is loaded in its own thread and the user can begin work after the first image has been loaded. This feature is especially useful on slow connection speed, 9.6 Kbps for example. The server side, which is implemented by the Java Servlet Engine works more effective than common gateway interface (CGI) programs do. Advantages of the Java Technology place this program on the next level of application development. This paper presents a unique application of Java in telemedicine. 相似文献
209.
Sponge development and antiquity of animal pattern formation 总被引:2,自引:1,他引:1
210.