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A review of 17 patients operated upon for unilateral hemifacial microsomia, and followed for up to 18 years, clarifies several principles of management. The management is facilitated by dysplasia predominance grouping, with the major functional deformity dictating the sequence of repair. Our surgical goals are: (1) provision of adequate upper airway; (2) preservation of normal teeth and adequate alveolar bone to achieve proper dental occlusion; (3) restoration of binaural hearing; (4) external ear construction; (5) acceptable facial symmetry; (6) balanced facial animation; and (7) a child with an acceptable self-image. 相似文献
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A spectrum of mutations in the second gene for autosomal dominant polycystic kidney disease (PKD2). 总被引:5,自引:0,他引:5
B Veldhuisen J J Saris S de Haij T Hayashi D M Reynolds T Mochizuki R Elles R Fossdal N Bogdanova M A van Dijk E Coto D Ravine S Nrby C Verellen-Dumoulin M H Breuning S Somlo D J Peters 《American journal of human genetics》1997,61(3):547-555
Recently the second gene for autosomal dominant polycystic kidney disease (ADPKD), located on chromosome 4q21-q22, has been cloned and characterized. The gene encodes an integral membrane protein, polycystin-2, that shows amino acid similarity to the PKD1 gene product and to the family of voltage-activated calcium (and sodium) channels. We have systematically screened the gene for mutations by single-strand conformation-polymorphism analysis in 35 families with the second type of ADPKD and have identified 20 mutations. So far, most mutations found seem to be unique and occur throughout the gene, without any evidence of clustering. In addition to small deletions, insertions, and substitutions leading to premature translation stops, one amino acid substitution and five possible splice-site mutations have been found. These findings suggest that the first step toward cyst formation in PKD2 patients is the loss of one functional copy of polycystin-2. 相似文献
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Over 11,000 second meiotic metaphase spreads stained for the pericentromeric region have been studied quantitatively in male mice of 14 strains. The sex-chromosome constitution of a cell could be judged objectively if X and Y chromosomes and ploidy were all scored. A bias arose if only Y chromosomes and ploidy were scored but could be corrected statistically. There was no sign of other forms of bias. The original contiguity of X and Y second metaphases in vivo was very occasionally evident in the preparations. Most of the subhaploid aneuploid counts were assumed to be artifactual. The incidence of truly aneuploid second metaphases in 13 strains was estimated as 0.38+/-0.12%. The estimated average rate per chromosome was 0.019+/-0.006%, with a comparable order of magnitude for the sex chromosomes alone. Simultaneous aneuploidy of two or more chromosomes of the haploid set was estimated to be very rare. Of the spreads from 13 strains, 9.6% were polyploid (2N, 3N, 4N) and showed most of the possible combinations of sex chromosomes. Nearly all the polyploid spreads were considered to arise by artifactual cell fusion at the time of second metaphase during the preparative technique, especially of the X and Y daughter-cell products of the first meiotic division. Other modes of origin (true polyploidy, accidental superposition of cells during preparation) were unlikely. The data could be accommodated by a statistical model with only four parameters. It allowed for artifactual fusion mainly between daughter cells but also between non-daughter cells, bias in one scoring method, and bias in the numbers of cells with given ploidy successfully mounted. Current techniques of chromosome preparation were thought to be wholly unsuitable for the recognition of true polyploidy. The artifactual origin of polyploid spreads was borne out by an absence of polyploid spermatozoa in 14 strains. There appeared to be a virtually constant transmission rate of paternal X and Y chromosomes from early meiosis to late blastocyst. The estimated rate of 49.05+/-0.67% with a Y chromosome also estimated the primary sex ratio. There was evidence of polymorphism in autosomal pericentromeric staining in 3 strains. No measure of the numbers of autosomes or sex chromosomes varied significantly between duplicate preparations or between duplicate males of a strain. 相似文献
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The cDNA of the second largest subunit of RNA polymerase II (or B) from HeLa cells has been cloned and sequenced. A predicted amino acid sequence of 1174 residues (calculated molecular mass of 133,896 Da) was derived from the longest open reading frame and compared to the sequences of homologous subunits of polymerases of eukaryotic, archaeal and bacterial origin. After optimal alignment, about 16% of the residues were found to be conserved throughout evolution, from human to Escherichia coli. About 2/3 of the overall length of the conserved domains delineated by these residues are clustered within the C-terminal half of the human polypeptide, whereas the remaining is spread over its N-terminal half. The putative functional significance of these conserved domains is discussed. 相似文献
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Aldehyde dehydrogenase 2 (ALDH2) is primarily responsible for detoxification of short-chain aldehydes in vivo. Previously it was reported that zebrafish has an aldh2 gene. Here we report the presence of a second aldh2 gene (aldh2b) in zebrafish. Zebrafish aldh2b locates adjacently to aldh2 on Chromosome 5 and the two genes share the same genomic organizations. aldh2b was predicted to encode a protein comprising 516 amino acids. The protein exhibits 95% amino acid identity with zebrafish ALDH2 and more than 76% identity with other vertebrate ALDH2s, respectively. Employing RT-PCR analysis, we demonstrated that both aldh2 and aldh2b mRNAs were present in embryos at cleavage stage (2 hpf: hour post fertilization) throughout protruding-mouth stage (72 hpf) and in different adult tissues of zebrafish. Taken together, our results reveal that zebrafish has two orthologues of aldh2 gene and the two genes share similar expression patterns during early development and in adult tissues. 相似文献
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The structure of the DNA oligomer d(G-G-G-G-C-C-C-C) has been determined at a resolution of 2.5 A by single-crystal X-ray methods. There are two strands in the asymmetric unit, and these coil about each other to form a right-handed double-helix of the A-type with Watson-Crick hydrogen bonds between base-pairs. The helix has a shallow minor groove and a deep, water-filled major groove; almost all exposed functional groups on the DNA are hydrated, and 106 ordered solvent molecules have been found. The two d(G-G-G-G).d(C-C-C-C) segments in the octamer exhibit similar and uniform structures, but there is a slight discontinuity at the GpC step between them. A recurring feature of the structure is the overlap of adjacent guanine bases in each GpG step, with the five-membered ring of one guanine stacking on the six-membered ring of its neighbour. There is little or no overlap between adjacent cytosine rings. Conformational parameters for these GpG steps are compared with those from other single-crystal X-ray analyses. In general, GpG steps exhibit high slide, low roll and variable twist. Models for poly(dG).poly(dC) were generated by applying a simple rotation and translation to each of the unmodified d(G-G-G-G).d(C-C-C-C) units. Detailed features of these models are shown to be compatible with various assays of poly(dG).poly(dC) in solution, and are useful in understanding the polymorphic behaviour of this sequence under a variety of experimental conditions. 相似文献
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Monocyte complement stimulator (MCS), a lymphokine previously shown to increase the rate of synthesis of the second complement component (C2) by human monocytes, is produced by sensitive T lymphocytes when exposed to antigen. MCS production requires cooperation of T lymphocytes with monocytes during the first 24 hr of exposure to antigen; both cell types must be capable of synthesizing protein during this time. MCS was found to differ from MIF in two ways: First, antigen-stimulated B lymphocytes and monocytes produce MIF but not MCS and second, MCS is destroyed by heating to 56 °C for 30 min while MIF retains its activity 相似文献
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A23187 and certain other carboxylate ionophores are capable of transferring Fe(II) but not Fe(III) across phospholipid bilayers (liposomes) and red cell membranes. A23187 is able to transfer Fe(II) from ferritin loaded liposomes when allied with a suitable redox couple and sink. The affinity of A23187 for Fe(II) is approximately five orders of magnitude greater than for Ca2+, as judged by two phase extraction techniques. 相似文献
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《新西兰生态学杂志》2011,22(1):17-24
Predator-free offshore islands play an important role in the conservation of many of New Zealand's endemic species. Takahe (Porphyrio mantelli) have small populations established on four offshore islands and although hatching success is lower than that of the wild mainland population in Fiordland, juvenile and adult survival is high and populations are growing exponentially. Accurate estimates of home range size and potential carrying capacities are therefore essential for the future management of the population as a whole. The mean home range size of takahe pairs in one study population on Mana Island (217 ha) was 2.8 ± 1.9 ha. The island was assessed for current and maximum available area for takahe and the potential carrying capacity was estimated at 22—53 pairs. Current and maximum available areas were also used to calculate carrying capacities on each of three other islands using two different estimates of mean home range size for Maud Island (7—34 pairs) and Kapiti Island (5—33 pairs) and one estimate of home range size for Tiritiri Matangi Island (25 pairs). A model of the population growth of takahe on islands predicted that estimated carrying capacities would be reached between 1997 and 2009. The urgency of planning to make use of the considerable potential of island populations of takahe is stressed. 相似文献
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A retrospective study of 932 second trimester terminations between 12-27 weeks gestation was carried out to determine the efficacy of gemeprost for second trimester termination. A single course of 5 x 1 mg gemeprost pessaries was administered every three hours. If abortion had not occurred after the first course of pessaries, a further course of 5 x 1 mg pessaries was administered. Intravenous oxytocin was administered after 36 hours if abortion had not occurred. Eighty per cent and ninety five per cent of patients aborted within 24 and 48 hours respectively. Of the remaining 5 per cent of women, 3 per cent aborted with escalating doses of oxytocin. In the remaining 18 (2 per cent) women, the pregnancies were electively terminated with an alternative method. The median induction-abortion interval was 18.0 hours and 15.0 hours in nulliparous and parous women respectively (P less than 0.0001). The number of pessaries required to induce abortion was not influenced by parity. Significantly more parous women bled more than 500 ml. The incidence of pelvic sepsis (0.1 per cent) and cervical tear (0.1 per cent) was low. Twenty six per cent of women had diarrhoea and 23 per cent vomited following administration of prostaglandin. This study confirmed the efficacy of gemeprost for second trimester termination of pregnancy. This method of termination is safe, non-invasive, simple and has a low complication rate. 相似文献
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P Prabakaran J An M M Gromiha S Selvaraj H Uedaira H Kono A Sarai 《Bioinformatics (Oxford, England)》2001,17(11):1027-1034
MOTIVATION: Protein-nucleic acid interactions are fundamental to the regulation of gene expression. In order to elucidate the molecular mechanism of protein-nucleic acid recognition and analyze the gene regulation network, not only structural data but also quantitative binding data are necessary. Although there are structural databases for proteins and nucleic acids, there exists no database for their experimental binding data. Thus, we have developed a Thermodynamic Database for Protein-Nucleic Acid Interactions (ProNIT). RESULTS: We have collected experimentally observed binding data from the literature. ProNIT contains several important thermodynamic data for protein-nucleic acid binding, such as dissociation constant (K(d)), association constant (K(a)), Gibbs free energy change (DeltaG), enthalpy change (DeltaH), heat capacity change (DeltaC(p)), experimental conditions, structural information of proteins, nucleic acids and the complex, and literature information. These data are integrated into a relational database system together with structural and functional information to provide flexible searching facilities by using combinations of various terms and parameters. A www interface allows users to search for data based on various conditions, with different display and sorting options, and to visualize molecular structures and their interactions. AVAILABILITY: ProNIT is freely accessible at the URL http://www.rtc.riken.go.jp/jouhou/pronit/pronit.html. 相似文献
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