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71.
Trisomy of the short arm of chromosome 17 (T17P) is a genomic disorder presenting with growth retardation, motor and mental retardation and constitutional physical anomalies including congenital heart defects. Here we report a case of near-complete T17P of which the genomic dosage aberrations were delineated by chromosomal microarray along with conventional diagnostic modalities. A 9-year-old Korean boy was admitted because of esophageal obstruction. He showed clinical manifestations of T17P, along with atypical features of scoliosis, corpus callosum agenesis, and seizure. Chromosome analyses revealed an inverted duplication of the chromosomal segment between 17p11.2 and 17p13.3. Chromosomal microarray revealed a duplication of the most of the short arm of chromosome 17 (size ~ 19.09 Mb) along with a cryptic deletion of a small segment of 17p terminal end (17pter) (~ 261 Kb). This is the first report of molecular characterization of near-complete T17P from inverted duplication in association with 17pter microdeletion. The fine delineation of the extent of genomic aberration by SNP-based microarray could help us better understand the molecular mechanism and genotype–phenotype correlations in T17P syndrome.  相似文献   
72.
Guidelines for the nomenclature of the human heat shock proteins   总被引:3,自引:2,他引:1  
The expanding number of members in the various human heat shock protein (HSP) families and the inconsistencies in their nomenclature have often led to confusion. Here, we propose new guidelines for the nomenclature of the human HSP families, HSPH (HSP110), HSPC (HSP90), HSPA (HSP70), DNAJ (HSP40), and HSPB (small HSP) as well as for the human chaperonin families HSPD/E (HSP60/HSP10) and CCT (TRiC). The nomenclature is based largely on the more consistent nomenclature assigned by the HUGO Gene Nomenclature Committee and used in the National Center of Biotechnology Information Entrez Gene database for the heat shock genes. In addition to this nomenclature, we provide a list of the human Entrez Gene IDs and the corresponding Entrez Gene IDs for the mouse orthologs.  相似文献   
73.
The recent multiplication of cladistic hypotheses for many zoological groups poses a challenge to zoological nomenclature following the International Code of Zoological Nomenclature: in order to account for these hypotheses, we will need many more ranks than currently allowed in this system, especially in lower taxonomy (around the ranks genus and species). The current Code allows the use of as many ranks as necessary in the family-series of nomina (except above superfamily), but forbids the use of more than a few ranks in the genus and species-series. It is here argued that this limitation has no theoretical background, does not respect the freedom of taxonomic thoughts or actions, and is harmful to zoological taxonomy in two respects at least: (1) it does not allow to express in detail hypothesized cladistic relationships among taxa at lower taxonomic levels (genus and species); (2) it does not allow to point taxonomically to low-level differentiation between populations of the same species, although this would be useful in some cases for conservation biology purposes. It is here proposed to modify the rules of the Code in order to allow use by taxonomists of an indeterminate number of ranks in all nominal-series. Such an 'expanded nomenclatural system' would be highly flexible and likely to be easily adapted to any new finding or hypothesis regarding cladistic relationships between taxa, at genus and species level and below. This system could be useful for phylogeographic analysis and in conservation biology. In zoological nomenclature, whereas robustness of nomina is necessary, the same does not hold for nomenclatural ranks, as the latter are arbitrary and carry no special biological, evolutionary or other information, except concerning the mutual relationships between taxa in the taxonomic hierarchy. Compared to the Phylocode project, the new system is equally unambiguous within the frame of a given taxonomic frame, but it provides more explicit and informative nomina for non-specialist users, and is more economic in terms of number of nomina needed to account for a given hierarchy. These ideas are exemplified by a comparative study of three possible nomenclatures for the taxonomy recently proposed by Hillis and Wilcox (2005) for American frogs traditionally referred to the genus Rana.  相似文献   
74.
Despite the fact that data deposition is not a generalised fact yet in the field of proteomics, several mass spectrometry (MS) based proteomics repositories are publicly available for the scientific community. The main existing resources are: the Global Proteome Machine Database (GPMDB), PeptideAtlas, the PRoteomics IDEntifications database (PRIDE), Tranche, and NCBI Peptidome. In this review the capabilities of each of these will be described, paying special attention to four key properties: data types stored, applicable data submission strategies, supported formats, and available data mining and visualization tools. Additionally, the data contents from model organisms will be enumerated for each resource. There are other valuable smaller and/or more specialized repositories but they will not be covered in this review. Finally, the concept behind the ProteomeXchange consortium, a collaborative effort among the main resources in the field, will be introduced.  相似文献   
75.
Amphibians, reptiles, birds and mammals serve as hosts for 19 species of Cryptosporidium. All 19 species have been confirmed by morphological, biological, and molecular data. Fish serve as hosts for three additional species, all of which lack supporting molecular data. In addition to the named species, gene sequence data from more than 40 isolates from various vertebrate hosts are reported in the scientific literature or are listed in GenBank. These isolates lack taxonomic status and are referred to as genotypes based on the host of origin. Undoubtedly, some will eventually be recognized as species. For them to receive taxonomic status sufficient morphological, biological, and molecular data are required and names must comply with the rules of the International Code for Zoological Nomenclature (ICZN). Because the ICZN rules may be interpreted differently by persons proposing names, original names might be improperly assigned, original literature might be overlooked, or new scientific methods might be applicable to determining taxonomic status, the names of species and higher taxa are not immutable. The rapidly evolving taxonomic status of Cryptosporidium sp. reflects these considerations.  相似文献   
76.
Most plant communities consist of different structural and ecological subsets, ranging from cryptogams to different tree layers. The completeness and approach with which these subsets are sampled have implications for vegetation classification. Non‐vascular plants are often omitted or sometimes treated separately, referring to their assemblages as “synusiae” (e.g. epiphytes on bark, saxicolous species on rocks). The distinction of complete plant communities (phytocoenoses or holocoenoses) from their parts (synusiae or merocoenoses) is crucial to avoid logical problems and inconsistencies in the resulting classification systems. We here describe theoretical differences between the phytocoenosis as a whole and its parts, and outline consequences of this distinction for practice and terminology in vegetation classification. To implement a clearer separation, we call for modifications of the International Code of Phytosociological Nomenclature and the EuroVegChecklist. We believe that these steps will make vegetation classification systems better applicable and raise recognition of the importance of non‐vascular plants in the vegetation as well as their interplay with vascular plants.  相似文献   
77.
Range-wide morphometric variability (cranial measurements) and genetic variability (nucleotide sequences of the cytochrome b gene) were investigated in the longface emperor, Lethrinus olivaceus (Lethrinidae), an emblematic large predatory fish of Indo-West Pacific coral reefs. Two cranial morphotypes were observed, one present from the Indian Ocean to the Coral Triangle and the other one, from the Coral Triangle to the western Central Pacific. The two morphotypes are concordant with reciprocally monophyletic mitochondrial lineages separated by 9.5% net nucleotide distance. These results suggest an old evolutionary history for L. olivaceus, which consists of two distinct species (Lethrinus sp. A in the Indian Ocean and Coral Triangle, Lethrinus sp. B in the western Pacific Ocean), whose distribution ranges meet or overlap in the eastern part of the Coral Triangle, in Taiwan and in West Papua. Lethrinus sp. A comprises two distinct mitochondrial lineages separated by 1.7% net nucleotide distance, one exclusive to the populations from the Indian Ocean, the other exclusive to Coral Triangle populations. The latter observation might be explained by vicariance, whereby the two lineages have been isolated from one another on either side of the Sunda Shelf because of low sea level in the Pleistocene. To clarify the nomenclature of this species complex, we recommend sequencing a fragment of the cytochrome b gene of the holotypes of L. olivaceus and of its first junior synonyms L. rostratus and L. waigiensis.  相似文献   
78.
Diagnosis and illustrations are given for Braunia secunda (Hook.) Bruch & Schimp., and a Humboldt and Bonpland specimen (BM) is selected as the lectotype. Also a collection by Arséne (BM) is designated as the lectotype for B. secunda var. crassiretis Thér. This variety is retained as synonym of B. secunda. The species concept of B. secunda is revised and a provisional key is provided to help in the identification of 23 species of Braunia, based on examination of herbarium specimens worldwide. About half of specimens from Mexico actually represent another species, B. andrieuxii Lorentz. All material examined from India, previously identified as B. secunda belongs to B. macropelma (Müll.Hal.) A.Jaeger, whereas collections from Africa are actually B. rupestris (Mitt.) A.Jaeger, B. entodonticarpa Müll.Hal., or B. diaphana (Müll.Hal.) A.Jaeger. These and other species should no longer be considered synonyms of B. secunda. The worldwide distribution of the species is documented for the United States, Mexico, Guatemala, Dominican Republic, Haiti, Venezuela, and Bolivia.  相似文献   
79.
We report here a child with a ring chromosome 2 [r(2)] associated with failure to thrive, microcephaly and dysmorphic features. The chromosomal aberration was defined by chromosome microarray analysis, revealing two small deletions of 2p25.3 (139 kb) and 2q37.3 (147 kb).  相似文献   
80.
Abstract

Research into root system morphology over the last two centuries has developed a diverse set of terminologies that are difficult to apply consistently across species and research specialties. In response to a need for better communication, a workshop held by the International Society for Root Research established some nomenclature standards for root research. These standards and their justification are presented in this study. A framework for a root system architectural taxonomy is created by defining four main classes of root: the tap root, that is, the first root to emerge from the seed; lateral roots, which are branches of other roots; shoot‐borne roots, which arise from shoot tissues; and basal roots, which develop from the hypocotyl, that is, the organ which is between the base of the shoot and the base of the tap root. It is concluded that adherence to the presented taxonomy will reduce confusion and eliminate some of the current confounding of results.  相似文献   
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