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91.
The benefits of achieving a long term event free survival of 60-70% by using increasingly intense treatment regimens must be weighed against the increased risk of treatment toxicity. From 1985 to 1990, 1612 children with childhood acute lymphoblastic leukaemia (ALL) in the UK were treated on MRC UKALL X with intensive induction therapy, central nervous system directed therapy (cranial irradiation and intrathecal methotrexate), and continuing treatment for two years. There was a randomisation to receive blocks of additional intensification treatment at five weeks, 20 weeks, not at all, or both. The five year disease free survival was 71% for children randomised to two blocks of intensification, a 14% improvement on children randomised to no intensification treatment. Treatment related mortality in this national multicentre study has been analysed for induction and first remission (including those after intensification treatment). There were 38 induction deaths, 2.3% and 53 deaths in first remission, 3.3% (including those from a second malignancy). Thirty one (84%) of the induction deaths followed an infection: bacterial in 22 and fungal in nine. Thirty seven infective remission deaths occurred: bacterial in 11, viral in 16, fungal in seven, and three caused by Pneumocystis carinii pneumonia. Ten of these deaths followed a block of intensification treatment. The majority of noninfective remission deaths followed the development of a second tumour. Risk analysis for an induction death showed girls and children with Down's syndrome to be at greater risk. For deaths in first remission analysis showed an increased risk for bone marrow transplant (BMT) patients and children with Down's syndrome. There was no effect of age and leucocyte count for either group. Most significantly when BMT patients were excluded from the analysis, intensification treatment did not increase the risk of remission death.  相似文献   
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1. 5-Hydroxytryptamine (5-HT) exerts both contractile and relaxant effects in the marmoset isolated aorta, actions that are unaffected by the 5-HT2 antagonist ketanserin. The aim of the present study was to define the receptors mediating the contractile activity of 5-HT in the marmoset aorta.
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A2 agonist U44069 in order to amplify the responses; or (ii) exposed to N ω-nitro- L -arginine (100 μmol/L) plus LY 53857 (0.1 μmol/L; a 5-HT2 receptor antagonist shown previously to inhibit relaxation). The effect of 5-HT on adenosine 3',5'-cyclic monophosphate (cAMP) formation was also investigated.
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT1D antagonist GR 127935; (iii) a contractile response to methysergide; (iv) a lack of effect of tropisetron, an antagonist of 5-HT3 and 5-HT4 receptors; and (v) inhibition of forskolin-stimulated cAMP formation by 5-HT (in the presence of LY 53857), indicative of negative coupling to adenylate cyclase.
4. The above effects fulfil the criteria for a 5-HT1-like receptor. In view of the previous finding that this contractile response is insensitive to ketanserin, it is concluded that the contractile effects of 5-HT in the marmoset aorta are mediated exclusively by a 5-HT1-like receptor.  相似文献   
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Background

The sudden increase in incidence and magnitude of mine blast injuries prompted us to highlight the problem and its management.

Methods

The cases of mine blast injuries occurring during mining and demining in a particular geographical area were analysed. Total 27 cases of mine blast injuries occurred during mining or demining operations in a period of 13 months.

Results

Various body regions were involved in the mine blast injuries but the main brunt was borne by feet and legs followed by multiple body regions due to splinters. 14 patients underwent below knee (BK) amputation while 4 patients required through knee (TK) amputations. The effect of blast was so severe that most of the cases required 2 to 5 times wound debridements. The initial aggressive debridement / open stump amputation saved the limb and life of all patients.

Conclusion

A mine blast causes extensive injuries and psychological trauma. Management is needed urgently, surgery is difficult, and amputation is often inevitable. Maximum lives and limbs can be saved with aggressive debridement, repeated inspections and dressings under anaesthesia and definitive closure at optimum time.Key Words: Amputation, Antipersonnel mine, Crush syndrome, Debridements, Mine blast injury, Secondary missiles, Shrapenels  相似文献   
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Over 200 measurements of the resting rate of oxygen consumption using an open-circuit method were made on 15 small babies nursed in their usual clinical setting during the first month of life. There were striking and persistent variations between babies that could not be explained by postnatal age, relationship to feed, sleep, or time of day. It was not possible from clinical examination to predict which babies had the higher or lower metabolic rates, except that babies who were light-for-dates generally had higher values. Because of these variations the appropriate thermal temperature for small babies cannot be predicted from average values adjusted for body weight and postnatal age alone.  相似文献   
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