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91.
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A practical and convenient procedure for making phosphotyrosine-containing peptides by the solid-phase method was developed. Phosphotyrosine was incorporated via Boc-Tyr(PO3Bzl2)-OH. The completed peptide was cleaved from the solid support by treatment with 1 M TMSBr-thioanisole-TFA. By gel-phase 31P-NMR spectroscopy we found that one of the benzyl protecting groups on phosphate was completely removed by two consecutive runs of Boc deprotection with 50% TFA-DCM. However, the other benzyl group remained intact throughout the synthesis (35 cycles).  相似文献   
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Summary. A luteinizing hormone releasing hormone agonist, d-Ser(But)6des Gly10-LHRH ethylamide, was administered intranasally to four women with unexplained ovulatory menorrhagia. Dramatic reductions in excessive menstrual blood losses were induced without significant side-effects, although the pattern of loss returned to pretreatment levels within 2 months of ceasing therapy.  相似文献   
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Modification of the kaolin clotting time has produced a reliable, simple assaysystem for antihemophilic factor. This system has been utilized for an investigation of the nature and mode of action of the circulating anticoagulantdirected against antihemophilic factor.

The anticoagulant has been shown to be present in equal amounts in plasmaand serum, to be associated with fractions II and III of plasma prepared bythe method of Cohn, to be relatively heat stable and to be stable for prolonged periods at -20 C.

Investigation of the kinetics of the anticoagulant-antihemophilic reactionhas demonstrated its temperature, time, pH, and substrate concentration dependency. The anticoagulant is not inactivated during the reaction with antihemophilic factor, and there is a proportional relationship between the anticoagulant and the antihemophilic factor during their interaction.

No antigen-antibody manifestations could be detected during the anticoagulant-antihemophilic factor reaction. These characteristics support thehypothesis that the inactivation of antihemophilic factor by specific circulatinganticoagulants is enzymatic.

Submitted on February 19, 1962 Accepted on April 6, 1962  相似文献   
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The staphylococcal scalded skin syndrome   总被引:2,自引:0,他引:2  
Histochemical and electron microscopic studies were carried out on the newborn mouse model of the staphylococcal scalded skin syndrome to investigate the mechanism of action of the staphylococcal epidermolytic toxin that causes it. Histochemical studies showed that an intra-epidermal split develops below the subcorneal zone which is rich in catabolic enzymes (the so-called esterase-acid phosphatase-rich band). However, histochemical alterations in the enzyme pattern could not be demonstrated. The earliest change revealed by electron microscopy was a widening of the intercellular space, with the formation of microvilli at the level between the stratum spinosum and stratum granulosum where the split later occurs. A clearing of the peripheral cytoplasm along the cell membranes was also revealed. In pre-split areas, adhesion between cell membranes of adjacent cells seems to be lost; desmosomes continue to hold the cells together but the split develops when these are broken by mechanical pressure. Later, damaged cell membranes may be seen. Extracellular keratinosomes remain unchanged. Although these findings do not agree with the already divergent results of other studies, they help support the findings of all groups that cases of the Lyell syndrome produced by staphylococci do not occur through necrolysis; it is therefore inappropriate to continue applying the term ‘toxic epidermal necrolysis’ to such cases.  相似文献   
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