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991.
Hospital risk management demands the development of broad and inclusive infection control policies. This is particularly true for anaesthetic equipment where appropriate recommendations on decontamination measures remains a difficult subject for infection control teams since there are no national guidelines. It is a topic which has perhaps been neglected in hospital infection control policies despite the widespread use of anaesthetic equipment in many clinical areas outside the theatre complex. This article offers practical guidance when preparing an infection control policy for anaesthetic equipment. The cost effectiveness of single patient use items versus reprocessing equipment is discussed. The importance of a multi-disciplinary approach, especially where the evidence base is weak, is highlighted. 相似文献
992.
A. S. Shera G. Rafique I. A. Khwaja J. Ara S. Baqai H. King 《Diabetic medicine》1995,12(12):1116-1121
The prevalence of diabetes mellitus and impaired glucose tolerance (IGT) and their relationship to age and obesity was estimated in the rural town of Shikarpur in Sindh Province, Pakistan by a population-based survey in 1994. Oral glucose tolerance tests were performed in a stratified random sample of 967 adults (387 men, 580 women) aged 25 years and above. The diagnoses of diabetes and IGT were made on the basis of WHO criteria. The response rate was 71% for men and 80% for women. The prevalence of diabetes was 16.2% (9.0% known, 7.2% newly diagnosed) in men, and 11.7% (6.3% known, 5.3% newly diagnosed) in women. The prevalence rose with age to a peak of 30% and 21% in 65–74 year-old men and women respectively. IGT was detected in 8.2% of men and 14.3% of women. Thus, total glucose intolerance (diabetes and IGT combined) was present in 25% of subjects examined. These results indicate that glucose intolerance in South Asians can no longer be regarded as a problem confined to migrant communities. Of the 72 subjects previously known to have diabetes, none was using insulin treatment, but 57 (79%) took oral hypoglycaemic agents. Central obesity and positive family history were strongly associated with diabetes, as was prevalence of hypertension. The association with central obesity was greater for women than for men, and suggests important, modifiable risk factor(s) related to lifestyle. 相似文献
993.
HUMAN PLACENTAL ACETYLCHOLINE CONTENT AND RELEASE AT PARTURITION 总被引:1,自引:0,他引:1
S. P. Brennecke S. Chen R. G. King A. L. A. Boura 《Clinical and experimental pharmacology & physiology》1988,15(9):715-725
1. Measurements were made of human placental acetylcholine (ACh) content and release into maternal and fetal circulations from placenta obtained before, during and after labours of both spontaneous and induced onsets. ACh content was determined in ex vivo placental biopsies using a radio-enzymatic assay. ACh release was determined by bioassay of the effluent from placental lobules perfused with amniotic fluid-like Kreb's containing physostigmine (2.4 mumol/l). 2. ACh content of placentae obtained after labour (spontaneous onset of labour, normal vaginal delivery) and during labour (spontaneous onset of labour, Caesarean section delivery) was significantly less than before labour (no labour onset, Caesarean section delivery). 3. Mean ACh output into maternal vessels 1.5-4.0 h after commencement of perfusion of placentae obtained after labour (spontaneous onset of labour, normal vaginal delivery) was significantly less than from those obtained before labour (no labour onset, Caesarean section delivery). No differences were found in ACh output into fetal vessels of placentae obtained before, during or after labour. 4. These results suggest a role for placental ACh in the events of human labour. The decrease in ACh content and maternal vascular release in placenta obtained after labour is consistent with a depletion of placental ACh during labour which may indicate ACh release at this time. The lack of any significant change in fetal vascular release of ACh in placenta obtained before, during or after labour, raises the possibility of different roles for ACh released into fetal and maternal vasculature. 相似文献
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998.
Point mutations in polypeptide VP1 of foot-and-mouth disease virus affect mouse virulence and BHK21 cell pathogenicity 总被引:1,自引:0,他引:1
Virus produced in the first four days after infection of a BHK21 culture was shown to differ from that produced later in the infection. The early virus caused large plaques in IB-RS-2 cell sheets, had a slow cytopathic effect in BHK21 cultures and showed a high virulence for suckling mice. In contrast, the late virus caused small plaques, was rapid in its cytopathic effect and was of low virulence for mice. Comparison between one clone each of the early and late virus showed that no change in immunogenic specificity had taken place, but that charge changes had occurred both in VP3 and in the large trypsin-resistant fragment of VP1. The early, large plaquing clone gave rise spontaneously to small plaquing virus during the destructive phase of a single passage in BHK21 cultures. Conversely, the late, small plaquing clone gave rise to large plaquing virus after a single passage in mice. Each new virus was cloned and it was shown that they differed in VP1. This indicated that missense mutations in the genome coding for the trypsin resistant fragment of VP1 were responsible for the biological changes observed. 相似文献
999.
The responses of spinocervical neurons to sinusoidal hair displacements were studied during and in the absence of radiant heating of parts of the hindpaw to noxious levels (45–65 °C). Noxious heat usually increased background discharge and lowered the signal-to-noise ratio at low frequencies of hair displacement. At higher frequencies over 20 Hz, this ratio was slightly depressed for half of the cells, and dramatically increased for the others. Similar effects were found when the heating was off the receptive field for hair displacement, which suggests a central cause for these effects. 相似文献
1000.