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Christoph Syldatk Vera Lehmensiek Gaby Ulrichs Ulrich Bilitewski Karsten Krohn Hartmut Höke Fritz Wagner 《Biotechnology letters》1992,14(2):99-104
Summary Resting cells of a mutant ofArthrobacter sp. (DSM 3747) were used for the bioconversion of D,L-5-benzylhydantoin and related compounds to the corresponding L-amino acids. After optimization of the reaction conditions in shake flask experiments, bioconversions were performed in a preparative scale in a 2-l-bioreactor under nitrogen atmosphere. Specific productivities of 0.4 (p-NO2-L-phenylalanine) up to 3.9 mM amino acid x g cell dry mass–1 x h–1 (p-Cl-L-phenylalanine) were obtained. D,L-5-p-COOH-Benzylhydantoin, D,L-5-phenylhydantoin and D,L-5-p-OH-phenylhydantoin were not accepted as substrates. 相似文献
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Nils Milman Niels Graudal Lillian Staub Nielsen Bjørn Mathiassen Palle Tauris Birgit Lund Jørgen Schøler Kristensen Kirsten Fenger 《Human genetics》1990,85(2):228-232
Summary Pedigree studies were performed based on one Faroese and four Danish probands with overt idiopathic hemochromatosis (IH). The study consisted of HLA typing and determination of biochemical iron status indicators (serum transferrin saturation, serum ferritin). In total, 130 persons were evaluated. The screening identified 6 homozygous (h/h) subjects with preclinical IH, 46 heterozygous (h/n), and 8 normal (n/n) subjects, while 39 subjects were classified as normal or heterozygous (n/h?). One family demonstrated both a homozygous x heterozygous as well as a heterozygous x heterozygous mating. Recombination between the HLA region and IH locus occurred possibly in three subjects in three different families. The significance of detailed screening in families with probands with IH is discussed. 相似文献
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The database systems PaleoTax and GONIAT provide detailed information on literature, taxonomy, morphology and occurrence of fossil invertebrate groups. PaleoTax is designed for Mesozoic corals, GONIAT for Paleozoic ammonoids, but both can be modified to cover other fossil groups. Both systems use dBASE format, but with different database structures. PaleoTax aims at the complete storage of all available objective data, GONIAT provides determinations based upon morphologic criteria, and includes information on geographic distribution and stratigraphic range of every taxon. A combination of both systems could lead to the establishment of a comprehensive paleontological information system useful for research and practical stratigraphic applications. 相似文献
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Ryszard Slomski Ingrid Braulke Claudia Behrend Elisabeth Schröder Jean-Pierre Colombo Jochen Reiss 《Human genetics》1992,89(6):632-634
Summary A girl with ornithine transcarbamylase (OTC) deficiency was investigated for molecular and cytogenetic abnormalities that might explain this phenotype. Analysis with polymorphic DNA markers indicated that the patient did not inherit paternal alleles of the OTC locus, but that she did inherit the proximal locus DXS7 and the long arm of chromosome X. High-resolution cytogenetic analysis of the patient indicated a deletion of Xp11.4-p21, whereas both parents had normal karytoypes. Since the mother might be heterozygous according to biochemical tests, a second mutation within the maternal OTC gene cannot be excluded. 相似文献
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Two MC1R loss‐of‐function alleles in cream‐coloured Australian Cattle Dogs and white Huskies 下载免费PDF全文
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Paul Karila Ann-Cathrine Jönsson Jörgen Jesen Susanne Holmgren 《Cell and tissue research》1993,271(3):537-544
The presence of galanin-like immunoreactivity in nerves to the stomach of the Atlantic cod has been investigated by immunohistochemistry. The distribution of ganglion cells showing galanin-like immunoreactivity was compared with the total distribution in nerves and ganglia. Projection studies were made to determine the origin of the galanin neurons. The effect of galanin was studied in smooth muscle strip preparations of the gut wall and arteries. Galanin-like immunoreactive ganglion cells frequently occurred along the vagal branches to the stomach. Most of them projected cranially. Immunoreactive nerve fibres were present in all layers of the gut and around arterial branches on the surface of the stomach. Ligations of the vagus and splanchnic nerves produced accumulations of immunoreactive material on both sides of the ligature. Galanin produced weak contractile effects unaffected by tetrodotoxin on the gut wall and on gut arteries. It is concluded that a population of the ganglion cells along the vagus nerve in the Atlantic cod contains a galanin-like peptide. Some of these cells may be parts of autonomic parasympathetic pathways innervating the gut of the Atlantic cod, having direct excitatory effects on the smooth muscles of the gut wall and gut arteries. 相似文献