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The article offers information on the study which investigates the morphological and ultrastructural characterization of hair follicle of Yuyi curly rats.

Superpixel can capture redundancy of the image and reduce the complexity of subsequent processing tasks. These advantages make it receive more and more attentions from researchers at home and abroad. This paper first analyzed the development of the superpixel segmentation, and summarized the state-of-the-art superpixel segmentation algorithms in the view of graph-based and gradient-ascent-based methods. Then, it compared several superpixel segmentation algorithms by experiments, and illustrated their strengths and weaknesses respectively. At last, it introduced the latest applications of superpixel segmentation techniques with prospects. [ABSTRACT FROM AUTHOR]

The article focuses on a study related to the molecular cloning of complementary DNA (cDNA) sequences which encode the epidermal growth factor (EGF) in Sprague Dawley (SD) rats. Topics discussed include the significance of polymerase chain reaction for cloning, use of the basic local alignment search tool program to determine single nucleotide polymorphism sites, and comparison of identities of cDNA sequences of EGF genes in SD rats with other species.

The mouse hairless gene is a crucial nuclear receptor gene associated with the structure of hair and skin. It encodes a putative zinc finger transcription factor, and is a transcriptional corepressor for thyroid hormone receptors. Hairless gene plays a critical role in maintaining the delicate balance between cell proliferation, differentiation, and apoptosis in the hair follicle as well as in the interfollicular epidermis, and is concerned with the control of hair growth cycling. This study was designed to clone and analyze the cDNA encoding Hr from Kunming mouse. The RT-PCR method was developed to clone the Hr cDNA. A full-length cDNA and CDS sequences of Kunming mouse were 4104bp and 3546bp, respectively, which has been accepted by GenBank (Accession Number: AY547391). Accession number of protein encoded by AY547391 sequence in GenBank is AAT45233 , composed of 1181 amino acid residues. The Hr cDNA of Kunming mouse was cloned and sequenced for the first time. The identities of CDS of Hr gene were 99.9%, 94.4%, 83.1%, 78.1%, 81.9% and 82.1% by homologous comparison among Kunming mouse and other six species, and that were 99.9%, 92.2%, 81.7%, 70.8%, 79.9% and 80.1% respectively in amino acid sequences. The results suggested a high degree of conservation and thus functional significance of the Hr gene among different mammalian taxons. The results derived from information searching by Blast program revealed that there were 4 SNP sites and one deletion mutation in the sequences of hairless gene mRNAs between Kunming mice and that collected in GenBank. Three SNP sites did not alter the related amino acids encoded. Two SNP proved to be polymorphism mutant sites with amino acids changes. The results provided new data for SNPs in Hr gene.

Using brother-sister inbreeding with forced heterozygosity to breed a new segregating inbred strain which carry mutant hairless gene. Then, genetic monitoring was conducted by the skin grafting test, coat color test and biochemical marker analysis, and its basic biological characteristics were studied with corresponding methods. The Results are that the Yuyi Hairless Mice (YYHL) with unique biological characteristics have been bred successfully and have progressed to 30th generation since 1991. Thirteen biochemical markers loci on nine chromosomes coding biochemical markers measured with electrophoresis were all homogenous. The skin grafting test showed that no dropping graft was found during 100 days after transplanting, implying the YYHL was of isohistogeneicity. Analysis of coat color genes indicated that the hair color of first generation hybrid crossed between YYHL and DBA/2 was all agouti suggesting that the coat color genes of the YYHL were homogenous. The gene type is AABBccDD. All these showed that the YYHL have been an inbred strain reaching the international standards.