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71.
Paul D Griffiths Jillian R Mann Philip J Darbyshire Anne Green 《BMJ (Clinical research ed.)》1988,296(6636):1583-1585
A pilot neonatal screening programme for haemoglobinopathies linked with screening for phenylketonuria and congenital hypothyroidism was reviewed. During 1978 to December 1986 137 000 neonates were tested. There were improvements in the detection rate and accuracy of diagnosis for homozygotes and mixed heterozygotes, mainly associated with the introduction of citrate agarose gel electrophoresis as a follow up procedure on all specimens showing any abnormality on the initial cellulose acetate electrophoresis.We recommend that the programme is continued on a service basis. 相似文献
72.
From the measures of evolutionary distance between pairs ofsequences in a set, it is possible to infer the genetic treeor trees which best fit these known data. DENDRON is a new program,written in FORTRAN 66, which computes an initial tree from thebottom-up, then searches among increasingly divergent treesfor a better fit. As a check on the consistency of the measures,the program tests all triplets for the triangle inequality.DENDRON also calculates a single top-down tree,progressing from the trunk to the twigs, for comparison withthe bottom-up trees.
Received on August 17, 1987; accepted on June 1, 1988 相似文献
73.
Pettit P 《Bioethics》1992,6(2):90-112
The ethical review of research on human beings, and indeed the ethical review of broader ranges of human activity, is a growth industry. I want to look here at the ethical review of research on humans and raise some questions about the direction it is taking. I am pessimistic about where the institutions that we have set up are leading us and I want to sound a warning note and suggest some changes that are needed in the practice of ethical review. 相似文献
74.
A soluble Lewis blood-group gene associated -3/4-L-fucosyltransferase has been purified from human milk by a series of steps involving hydrophobic chromatography on Phenyl Sepharose 4B, ion exchange chromatography on CM-Sephadex C-50, affinity chromatography on GDP-hexanolamine Sepharose 4B and gel filtration on Sephacryl S-200. The first step separated -3-L-fucosyltransferase activity directed towardsN-acetylglucosamine in Type 2 (Gal1-4GlcNAc-R) acceptors from an -3/4-fucosyltransferase fraction acting on both Type 1 (Gal1-3GlcNAc-R) and Type 2 acceptors. Further purification of this latter fraction on CM-Sephadex and GDP-hexanolamine Sepharose gave a single peak of fucosyltransferase activity that catalysed the addition of fucose toN-acetylglucosamine in both Type 1 and Type 2 acceptors and to theO-3 position of glucose in lactose-based oligosaccharides. The enzyme preparation at this stage resembled previously described -3/4-fucosyltransferase preparations purified from human milk. However, gel filtration of this preparation on Sephacryl S-200 or Sephadex G-150 separated further amounts of -3-fucosyltransferase activity acting solely on Type 2 acceptors and left a residual -3/4-fucosyltransferase that retained strong -4 activity with the Type 1 acceptor, lacto-N-biose 1, and -3 activity with 2-fucosyllactose, but had relatively little -3 activity withN-acetyllactosamine and virtually no capacity to transfer fucose to glycoproteins withN-linked oligosaccharide chains having unsubstituted terminal Type 2 structures. 相似文献
75.
The mechanism responsible for the initial steps in the anaerobic degradation of trans-cinnamate and -phenylalkane carboxylates by the purple non-sulphur photosynthetic bacterium Rhodopseudomonas palustris was investigated. Phenylacetate did not support growth and there was a marked CO2 dependence for growth on acids with greater side-chain lengths. Here, CO2 was presumably acting as a redox sink for the disposal of excess reducing equivalents. Growth on benzoate did not require the addition of exogenous CO2. Aromatic acids with an odd number of side-chain carbon atoms (3-phenylpropionate, 5-phenylvalerate, 7-phenylheptanoate) gave greater apparent molar growth yields than those with an even number of side-chain carbon atoms (4-phenylbutyrate, 6-phenylhexanoate, 8-phenyloctanoate). HPLC analysis revealed that phenylacetate accumulated and persisted in the culture medium during growth on these latter compounds. Cinnamate and benzoate transiently accumulated in the culture medium during growth on 3-phenylpropionate, and benzoate alone accumulated transiently during the course of trans-cinnamate degradation. The transient accumulation of 4-phenyl-2-butenoic acid occurred during growth on 4-phenylbutyrate, and phenylacetate accumulated to a 1:1 molar stoichiometry with the initial 4-phenylbutyrate concentration. It is proposed that the initial steps in the anaerobic degradation of trans-cinnamate and the group of acids from 3-phenylpropionate to 8-phenyloctanoate involves -oxidation of the side-chain.Abbreviation 3-PP
3-phenylpropionic acid
- 4-PB
4-phenylbutyric acid
- 5-PV
5-phenylvaleric acid
- 6-PH
6-phenylhexanoic acid
- 7-PH
7-phenylheptanoic acid
- 8-PO
8-phenyloctanoic acid
- 4-P2B
4-phenyl-2-butenoic acid
- GC/MS
Gas chromatography/Mass spectrometry
- HPLC
High-pressure liquid chromatography 相似文献
76.
Atomic force microscopy examination of the topography of a hydrated bacterial biofilm on a copper surface 总被引:7,自引:0,他引:7
A bacterium, designated CCI#8, that was isolated from a corroded copper coupon colonized both polished and unpolished copper surfaces under batch culture conditions. Atomic Force Microscopy (AFM) images revealed that the biofilm was heterogeneous in nature, both in depth and in cell distribution. Bacterial cells were shown to be associated with pits on the surface of the unpolished copper coupons. These observations support previous studies that CCI#8 is associated with the pitting corrosion of copper. 相似文献
77.
Stefan Jansson Eran Pichersky Roberto Bassi Beverley R. Green Masahiko Ikeuchi Anastasios Melis David J. Simpson Michael Spangfort L. Andrew Staehelin J. Philip Thornber 《Plant Molecular Biology Reporter》1992,10(3):242-253
We propose a nomenclature for the genes encoding the chlorophylla/b-binding proteins of the light-harvesting complexes of photosystem I and II. The genes encoding LHC I and LHC II polypeptides
are namedLhca1 throughLhca4 andLhcb1 throughLhcb6, respectively. The proposal follows the general format recommended by the Commision on Plant Gene Nomenclature. We also present
a table for the conversion of old gene names to the new nomenclature. 相似文献
78.
Elliot Meyerowitz the Biology Department, Caltech, and a member of the Board of Directors of the ISPMB, has been named Fellow of the American
Academy of Arts and Science. 相似文献
79.
Monica J. Justice Bebra J. Gilbert Kenneth W. Kinzler Bert Vogelstein Authur M. Buchberg Jeffrey D. Ceci Yoichi Matsuda Verne M. Chapman Christos Patriotis Antonios Makris Philip N. Tsichlis Nancy A. Jenkins Neal G. Copeland 《Genomics》1992,13(4):1281-1288
An interspecific backcross between C57BL/6J and Mus spretus was used to generate a molecular genetic linkage map of mouse chromosome 18 that includes 23 molecular markers and spans approximately 86% of the estimated length of the chromosome. The Apc, Camk2a, D18Fcr1, D18Fcr2, D18Leh1, D18Leh2, Dcc, Emb-rs3, Fgfa, Fim-2/Csfmr, Gnal, Grl-1, Grp, Hk-1rs1, Ii, Kns, Lmnb, Mbp, Mcc, Mtv-38, Palb, Pdgfrb, and Tpl-2 genes were mapped relative to each other in one interspecific backcross. A second interspecific backcross and a centromere-specific DNA satellite probe were used to determine the distance of the most proximal chromosome 18 marker to the centromere. The interspecific map extends the known regions of linkage homology between mouse chromosome 18 and human chromosomes 5 and 18 and identifies a new homology segment with human chromosome 10p. It also provides molecular access to many regions of mouse chromosome 18 for the first time. 相似文献
80.
J M Suttie D L Foster B A Veenvliet T R Manley I D Corson 《Journal of reproduction and fertility》1991,92(1):33-39
The effect of maintaining female sheep at a body weight intermediate between the normal weight for puberty (30-35 kg) and 20 kg (puberty suppressed) on the onset of oestrous cycles was studied. In addition, the influence of ad-libitum food intake or insulin infusion was studied in animals previously maintained at 20 kg. Coopworth ewe lambs (10 weeks old) were allocated to one of 6 treatments: (A) ad-libitum fed (n = 6), (B) ad-libitum fed to 28 kg then maintained at that weight (n = 6), (C) ad-libitum fed to 24 kg then maintained at that weight (n = 6), (D) maintained at 20 kg until Week 29 and then fed ad libitum (n = 6), (E) maintained at 20 kg and infused with 0.1 U insulin/kg/24 h for 2 weeks from 29-31 weeks of age (n = 5), (F) maintained at 20 kg (n = 6). The lambs were penned indoors under natural photo-period, which was decreasing virtually throughout the study, and fed a pelleted concentrate diet which was recorded daily. They were blood sampled twice a week, and plasma was analysed for progesterone. Puberty was defined as the date when plasma concentrations of progesterone first exceeded 1 ng/ml. In addition, ewes in Groups D, E and F were blood sampled every 10 min for 8 h on Days 0 and +12 of the insulin infusion or access to ad-libitum feeding and the plasma was analysed for luteinizing hormone (LH).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献