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971.
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In malignant hyperthermia, myophosphorylase reaction shows characteristic changes that take place within minutes: (1) a generally strongly weakened reaction; (2) numerous negatively reacting fibres; (3) frequently, fibre sections that show spotty and/or striatal weak or negative reactions and fibre sections with strong striatal reactions with relatively narrow sarcomere spacings (a "sign of hypercontraction"). Obviously, the morphological findings that show characteristic "striated fibres" are typical of the malignant hyperthermia syndrome! It is important to note that the muscular fibres showing such changes are, as a rule, inconspicuous when using other stains and reactions. These pathological myophosphorylase reactions were observed in five deceased patients (one independently of anaesthesia after an extended walk) and in 19 pigs (18 times after halothane testing and once in an experimental animal with clinical evidence of the presence of malignant hyperthermia). These reactions were not noted in pigs with negative halothane reactivity or prior to halothane testing. They were also not seen in a large number of very different healthy and diseased control and reference cases from our biopsy and autopsy material. Myophosphorylase reaction enables convincing demonstration of malignant hyperthermia, past or present. Hence, it is possible to elucidate puzzling deaths or verify apparently clear death occurring during or subsequent to anaesthesia or simply following stress ("human stress syndrome"). Many of these deaths doubtlessly escape the attention of clinicians using the usual morphological examination methods. However, the reaction cannot be used to identify potential victims.  相似文献   
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The abuse of heroin (diacetylmorphine) in Singapore escalated sharply in 1975 and 1976, as indicated by the 35-fold increase in the number of heroin seizures and the 20-fold increase in the urine samples containing morphine since 1974. A rapid and simple GC method has been described to estimate diacetylmorphine (and caffeine). Monoacetylmorphine and acetylcodeine may be ascertained by an additional step involving acetylation. All gas chromatograms of a large number of samples analyzed consistently had the same pattern, indicating that they possibly had a common origin. This GC "fingerprint," together with the quantitative data, appears to be characteristic of the illicit Asian or Chinese type of heroin found in Singapore. The proportions of the four major ingredients in some twelve typical samples have been tabulated. Statistical data confirming the accuracy and reproducibility of the analytical method have also been presented.  相似文献   
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