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  总被引:2,自引:0,他引:2  
Hsu  L; Prentice  RL; Zhao  LP; Fan  JJ 《Biometrika》1999,86(4):743-753
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The "cricket bat" flap: a one-stage free forearm flap phalloplasty   总被引:2,自引:0,他引:2  
Total and subtotal penile reconstruction represents a major surgical challenge. We present a new method and two illustrative cases using a modified design of the radial forearm free-tissue transfer: the "cricket bat" flap.  相似文献   
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alpha 1-Proteinase inhibitor (alpha 1-PI), a member of the serineproteinase inhibitor superfamily, has a primary role in controllingneutrophil elastase activity within the mammalian circulation. Severalstudies have indicated that the reactive center region of alpha 1-PI, theamino acid sequence of which is critical to recognition of and binding totarget proteinases, is highly divergent within and among species. Thisappears to be a consequence of accelerated rates of evolution that may havebeen driven by positive Darwinian selection. In order to examine this andother features of alpha 1-PI evolution in more detail, we have isolated andsequenced cDNAs representing alpha 1- PI mRNAs of the mouse species Mussaxicola and Mus minutoides and have compared these with a number of othermammalian alpha 1-PI mRNAs. Relative to other mammalian mRNAs, the extentof nonsynonymous substitution is generally high throughout the alpha 1-PImRNA molecule, indicating greater overall rates of amino acid substitution.Within and among mouse species, the 5'-half of the mRNA, but not the3'-half, has been homogenized by concerted evolution. Finally, the reactivecenter is under diversifying or positive Darwinian selection in muridrodents (rats, mice) and guinea pigs yet is under purifying selection inprimates and artiodactyls. The significance of these findings to alpha 1-PIfunction and the possible selective forces driving evolution of serpins ingeneral are discussed.  相似文献   
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This work presents the results of a demographic analysis of 30 years of breeding records from the University of Washington's recently closed Primate Field Station at Medical Lake, Washington. Summaries of population growth, age-specific fertility and mortality rates, first-year survival, and seasonality of reproduction are presented, as well as an analysis of survival by decade. In addition, we present data on interbirth intervals in this population. In general, pigtailed macaques represent a typical Old World monkey pattern of age-specific fertility and mortality, with a few minor exceptions. We suggest that pigtailed macaques are most similar to rhesus and Barbary macaques, and that Japanese and bonnet macaques differ somewhat in their demographics.  相似文献   
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Arginine decarboxylase (ADC) is an important enzyme in the production of putrescine and polyamines in plants. It is encoded by a single or low-copy nuclear gene that lacks introns in sequences studied to date. The rate of Adc amino acid sequence evolution is similar to that of ndhF for the angiosperm family studied. Highly conserved regions provide several target sites for PCR priming and sequencing and aid in nucleotide and amino acid sequence alignment across a range of taxonomic levels, while a variable region provides an increased number of potentially informative characters relative to ndhF for the taxa surveyed. The utility of the Adc gene in plant molecular systematic studies is demonstrated by analysis of its partial nucleotide sequences obtained from 13 representatives of Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order Capparales) and 1 from the related order Malvales. Two copies of the Adc gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied to data except the basal genus Aethionema. The resulting Adc gene tree provides robust phylogenetic data regarding relationships within the complex mustard family, as well as independent support for proposed tribal realignments based on other molecular data sets such as those from chloroplast DNA.   相似文献   
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Patterns of mitochondrial DNA (mtDNA) variation were examined in 133 mole-rats constituting all four chromosomal species (2n = 52, 2n = 54, 2n = 58, and 2n = 60) of the Spalax ehrenbergi superspecies in Israel, as well as the peripheral isolates of 2n = 60. In the main range of the complex, a total of 28 mtDNA haplotypes were found in 64 mole-rats, with most haplotypes being unique to either a single chromosomal species or population. mtDNA divergence increased from low to high diploid number in a north-to-south direction in Israel. Overall levels of mtDNA diversity were unexpectedly the highest in the 2n = 60, the youngest species of the complex. The mtDNA haplotypes can be separated into two major groups, 2n = 52-54 and 2n = 58-60, and a phylogenetic analysis for each group revealed evidence of a few haplotypes not sorted by diploid number. The overall patterns of mtDNA divergence seen within and among the four chromosomal species are consistent with the parapatric mode of speciation as suggested from previous studies of allozyme and DNA hybridization. In a separate data set the patterns of mtDNA variation were examined across the main geographic range and across peripheral semi-isolates and isolates of the 2n = 60 chromosomal species. Fifteen haplotypes were found in 69 mole-rats. High levels of mtDNA diversity characterized the main range, semi-isolated, and even some desert isolated populations. The peripheral isolates contain much mtDNA diversity, including novel haplotypes.   相似文献   
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