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951.
952.
OBJECTIVES--To document the number of children aged less than 15 years who developed diabetes and were managed within one large health district, and to evaluate the outcome of those children managed without hospital admission at diagnosis. DESIGN--A retrospective study over 1979-88, when a paediatrician and a physician with special interests in childhood diabetes initiated joint clinics. Data collected from the district diabetes register and files of consultants and health visitors specialising in diabetes. SETTING--Referral of children to consultants in Leicestershire (total population 863,000). MAIN OUTCOME MEASURES--The proportion of children managed without hospital admission, comparison of readmission rates and glycated haemoglobin concentrations between children admitted and those not admitted. RESULTS--Over 10 years 236 children aged 10-14 years developed diabetes (annual incidence rate 12.8/100,000 child population (95% confidence interval 11.3 to 14.7)). In total 138 were not admitted to hospital but received supervised management based at home. Admitted children were younger or acidotic or their family doctors did not contact the diabetes team. Duration of admission declined from seven days in 1979-80 to three days in 1987-8. Ninety two were not admitted to hospital during the 10 years for any reason. Significantly fewer children who received management at home were readmitted for reasons related to diabetes than the group treated in hospital (30 (22%) v 40 (41%); p = 0.004). Concentrations of glycated haemoglobin were no different between the two groups. CONCLUSIONS--Children with newly diagnosed diabetes may be safely and effectively managed out of hospital. Domiciliary or community based management depends on the commitment of consultants specialising in diabetes working in close cooperation with general practitioners, specialist nurses in diabetes, and dietitians.  相似文献   
953.
Peroxisomal membrane proteins (PMPs) from the Swiss-Webster mouse are analyzed and compared to those of rats and humans using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. A purification procedure for fresh mouse, rat, or human biopsy liver which enriches peroxisomal/mitochondrial marker enzyme ratios over 100-fold is characterized. When analyzed by SDS-PAGE, membranes of purified liver peroxisomes are shown to contain the same complement of 145-, 70-, 55-, 36-, and 22-kDa PMPs in rats, mice, and humans. A rabbit polyclonal antibody raised against mouse peroxisomal membranes demonstrates immunoreactivity to 145- and 70-kDa proteins in fresh liver homogenates from all three species and in control or Zellweger syndrome fibroblasts from humans. Human autopsy or placental tissues which were refrigerated before analysis exhibited 105-, 55-, and 36-kDa peptides which may be derived from the 145- and 70-kDa peptides. Such conversions, if related to degradation, may explain difficulties in purifying peroxisomes from human autopsy specimens. Variable amounts of the 55-kDa peptide also occurred in mouse adrenal and lung, and the conversion of higher to lower molecular weight PMPs could not be demonstrated by in vitro incubation of mouse liver. Further definition of the structure and variability of mammalian PMPs should be helpful in understanding polyenzymopathies such as Zellweger syndrome.  相似文献   
954.
High resolution 13C NMR spectroscopy of live cells has been used to show that poly-beta-hydroxybutyrate (PHB) is predominantly in a mobile state within the storage granules of Alcaligenes eutrophus, Methylobacterium extorquens, and Methylobacterium AM1. Comparison of chemical and NMR analysis of PHB indicates that about 70% of the polymer in A. eutrophus gives sharp observable resonances. Temperature-dependent line widths and relaxation rates together with nuclear Overhauser effect measurements demonstrate that the observed material is effectively a mobile amorphous elastomer that is well above its glass transition temperature. The hydroxyvalerate-hydroxybutyrate copolymer produced by propionate-fed A. eutrophus has virtually the same mobility as the homopolymer. Evidence is presented indicating that water is an integral component of the PHB granule and that this component acts as a plasticizer for the polymer. These observations strongly suggest that the enzyme(s) responsible for PHB biosynthesis and consumption operate only on mobile hydrated material and that the solid granules characteristic of dried cells are partially artifactual. This model is supported by a reinterpretation of previously inexplicable biochemical results.  相似文献   
955.
Short chain flavour esters synthesis by microbial lipases   总被引:6,自引:0,他引:6  
Summary The peparative synthesis of 35 short chain flavour esters by lipases fromMucor miehi, Aspergillus sp.,Candida rugosa andRhizopus arrhizus was investigated in organic media. Acetic, propionic, butyric, valeric and caproic acids, as well as methanol, ethanol, butanol, i-pentanol, hexanol, citronellol and geraniol were used as substrates. Most of the esters were synthesized in good yield by at least one of the lipase preparations tested. Different conversion yields were observed according to the lipase specificity toward the acid or the alcohol moiety of the ester. Methyl- and ethyl acetates were also produced by changing the organic solvent. Enzymatic catalysis in organic solvent is thought to be a valuable method for preparative synthesis of flavour esters.  相似文献   
956.
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958.
To determine a possible relationship between organismal and molecular evolution, the divergence patterns of gene families were examined by taking special notice of functional difference, tissue distribution, and intracellular localization of the members. A phylogenetic analysis of 25 different gene families revealed interesting patterns of divergence of these families: Most gene duplications giving rise to different functions antedate the vertebrates-arthropods separation. On the other hand, in a group of members carrying virtually identical function to one another but differing in tissue distribution (tissue- specific isoform), most gene duplications have occurred independently in each of vertebrates and arthropods after the separation of the two animal groups. In family members encoding molecules localizing in cell compartments (compartmentalized isoforms), the gene duplications antedate the animals-fungi separation. In the cases of the Ca2+ pump and rab subfamilies, the compartmentalized isoforms were shown to have diverged during the early evolution of eukaryotes. A phylogenetic analysis of the tissue-specific isoforms from 26 different subfamilies revealed extensive gene duplications and rapid rates of amino acid substitutions in the early evolution of chordates before the separation of fishes and tetrapods. On the contrary, the genetic variations are relatively low in the later period. This pattern of evolution observed at the molecular level is correlated well with that of tissue evolution based on fossil evidence and morphological data, and thus evolution at the two levels may be related.   相似文献   
959.
960.
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