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Polypeptide components of an excitable plasma membrane 总被引:4,自引:0,他引:4
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S D Shorvon M W Carney I Chanarin E H Reynolds 《BMJ (Clinical research ed.)》1980,281(6247):1036-1038
The neuropsychiatric states of 50 patients with vitamin B12 deficiency and 34 patients with folate deficiency presenting with megaloblastosis in a general hospital were examined and compared. Abnormalities of the nervous system were found in two-thirds of both groups. Peripheral neuropathy was the most common condition associated with vitamin B12 deficiency and affective disorder with folate deficiency. The proportions of patients with organic mental change were similar in the two groups. Subacute combined degeneration of the cord was an uncommon complication and occurred only in the patients with vitamin B12 deficiency. There was no relation between haematological and neuropsychiatric abnormalities. The neuropsychiatry of megaloblastic anaemia seen in this study of patients presenting to haematologists or general physicians contrasts with that reported previously, before haematological techniques for separating the two deficiencies were introduced. 相似文献
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An analysis of 18,940 deliveries between 1981 and 1984 in a large British obstetric unit showed marked changes in the management of the second stage of labour. These changes included an increase in the length of the second stage (especially among primiparous women), a rise in the rate of spontaneous delivery and a large decline in the rate of episiotomy. There was no change in neonatal outcome or in the rate of maternal postpartum complications. These findings may have resulted from a more conservative approach to the management of the second stage. They may also reflect a better understanding among obstetric professionals of what constitutes a normal second stage and therefore better decisions about when to act and when to wait. 相似文献
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The rabbit Acrosome Stabilizing Factor (ASF) is a glycoprotein synthesized in the corpus epididymis that reversibly decapacitates sperm. The effects of altering the conformation of ASF were evaluated by using a competitive enzyme-linked immunoabsorption assay (ELISA) with monoclonal antibodies that recognized either sequential or conformational determinants and/or an in vivo decapacitation assay. Heat denaturation (80 degrees C for 30 min) of affinity-purified ASF resulted in destruction of its native conformation concurrent with its loss of biological activity. Acid pH treatment of ASF also resulted in a conformational change in ASF, which caused a shift from the dimeric form (MW = 260,000) to the monomeric form (MW = 130,000). This manipulation allowed the biological activity of the monomeric form of ASF to be assayed separately from the dimer. The monomer was found to be biologically inactive. Proteolysis with trypsin or Staphylococcus-V8 treatment resulted in loss of the native conformation of the molecule, but Staphylococcus-V8 did not destroy the sequential determinant recognized in this analysis. This work indicates that conformation of the ASF macromolecule is important for its biological activity, and also provides a rapid means to evaluate potential decapacitation activity of purified ASF. 相似文献
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Solvation effects 总被引:1,自引:0,他引:1