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Tests of orientation, concentration and shortterm visual memorywere used to assess 72 patients 1 day before, and 2 days after,elective major surgery. Patients were premedicated with papaveretumand either atropine or glycopyrrolate, before receiving a standardgeneral anaesthetic. Those who had received atropine showedsignificant postoperative short-term memory deficit (P< 0.01),but no change in orientation or concentration. Those who hadbeen given glycopyrrolate showed no significant cognitive changesafter surgery. As glycopyrrolate does not cross the blood-brainbarrier freely, these findings support the involvement of centralcholinergic mechanisms in the deterioration of cognitive functionin the postoperative period.  相似文献   
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1 Heterocyclic amines are formed in parts per billion levels when meat is cooked.
2 The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food.
3 We have shown that MeIQx and PhIP, both in vitro and in vivo , are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines.
4 MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt , we have shown that PhIP induces a characteristic mutational 'fingerprint'.
5 MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats.  相似文献   
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This study assesses the relative importance of history, examination and investigations in paediatric diagnosis, in the Paediatric Out-patient Department of the Central Middlesex Hospital, London, by means of a questionnaire-based record of 94 consecutive referrals. A diagnosis identical to the final diagnosis was made in 76% of referrals after taking a history. The general practitioner had proposed a diagnosis in 45% in the referral letter. Clinical examination changed the diagnosis in only 15% but increased diagnostic confidence in 33%. Ninety-one per cent of cases were diagnosed without recourse to investigations. Forty-two per cent of children referred had investigations performed. In the majority of paediatric cases the provisional diagnosis reached after taking a history was identical to that after examination or results of investigations were known. Although examination provided a final diagnosis in only 15% of all cases it played an important role in adding confidence in 33%. More educational effort should therefore be directed at clinical history-taking skills and the subsequent purpose of examination.  相似文献   
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Acromegaly is associated with abnormal indices of body composition(as determined by exchangeable sodium, exchangeable potassiumand total body water estimations) which may be corrected bytreatment. We related these indices of body composition to theattained growth hormone levels (mean of five daytime values)in 42 treated acromegalics. Somatomedin C was measured in 30subjects. The mean duration of treatment was 7.7 years (range1–26). Exchangeable sodium, potassium and total body waterwere significantly lowered by treatment. After treatment of acromegaly subjects whose growth hormonelevel was below 5 mU/1 achieved normal body composition moreoften than those with higher levels. Growth hormone concentrationof below 5 mU/1 after treatment should be regarded as a moreappropriate index of control of acromegaly than the higher levelspreviously recommended.  相似文献   
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Purely public water supply systems are characterized by highcosts, insufficient supplies and chronic deficits that are coveredby central government transfers. The private water supply programmein Abidjan has not met its coverage targets either, but thesystem has remained financially solvent and fostered a rapidgrowth in capacity through the informal sector. The materialreviewed here and the experience of developing country watersystems in general support several conclusions. (1) Water vendingis common in developing countries, which suggests that chargingfor water is not culturally unacceptable. Demand for wastewaterservices is low, but surcharges could be imposed on water usageto cover some sanitation costs. (2) Incentives are criticalto sound management of water supply and sanitation services.They are typically part of the structure of private firms, butare rare in publicly run systems. (3) The private sector's rolein the provision of water supply and sanitation can be extensive.Regulation of private activity and quality control by publicauthorities is essential to maintain competition and ensureproper and fair operation. (4) Public efforts to supply watercan be supplemented by a government-regulated, parallel systemto increase the amount of water available. Normally these systemsinvolve trucked water, but private sales outlets with pipe infrastructureshould be encouraged where feasible. (5) Even where the publicsector decides to control and operate the water supply and sanitationsystem, some partnership with the private sector is possiblethrough contracting out specific tasks such as billing, metering,maintenance of various components or tracking water losses.Finally, the supply of water is an ideal activity for a public-privatepartnership. Both sectors have comparative advantages that arebest applied in conjunction with the other.  相似文献   
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