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The haemolymph of the maritime earwig, Anisolabis littorea, has been analysed for inorganic and organic components. The inorganic fraction has a high sodium ion concentration and osmotic pressure but a relatively lower chloride ion concentration. The organic fraction has a high amino acid content—the principal ones being proline, alanine, glutamic acid, and glutamine, and tyrosine. In contrast to the high aminoacidemia there is a very low carbohydrate content and no detectable trehalose in the haemolymph. The evolution of the composition of insect blood is discussed. 相似文献
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Anna Pearce Catherine Law David Elliman Tim J Cole Helen Bedford 《BMJ (Clinical research ed.)》2008,336(7647):754-757
Objectives To estimate uptake of the combined measles, mumps, and rubella vaccine (MMR) and single antigen vaccines and explore factors associated with uptake and reasons for not using MMR.Design Nationally representative cohort study.Setting Children born in the UK, 2000-2.Participants 14 578 children for whom data on immunisation were available.Main outcome measures Immunisation status at 3 years defined as “immunised with MMR,” “immunised with at least one single antigen vaccine,” and “unimmunised.”Results 88.6% (13 013) were immunised with MMR and 5.2% (634) had received at least one single antigen vaccine. Children were more likely to be unimmunised if they lived in a household with other children (risk ratio 1.74, 95% confidence interval 1.35 to 2.25, for those living with three or more) or a lone parent (1.31, 1.07 to 1.60) or if their mother was under 20 (1.41, 1.08 to 1.85) or over 34 at cohort child’s birth (reaching 2.34, 1.20 to 3.23, for ≥40), more highly educated (1.41, 1.05 to 1.89, for a degree), not employed (1.43, 1.12 to 1.82), or self employed (1.71, 1.18 to 2.47). Use of single vaccines increased with household income (reaching 2.98, 2.05 to 4.32, for incomes of ≥£52 000 (€69 750, $102 190)), maternal age (reaching 3.04, 2.05 to 4.50, for ≥40), and education (reaching 3.15, 1.78 to 5.58, for a degree). Children were less likely to have received single vaccines if they lived with other children (reaching 0.14, 0.07 to 0.29, for three or more), had mothers who were Indian (0.50, 0.25 to 0.99), Pakistani or Bangladeshi (0.13, 0.04 to 0.39), or black (0.31, 0.14 to 0.64), or aged under 25 (reaching 0.14, 0.05 to 0.36, for 14-19). Nearly three quarters (74.4%, 1110) of parents who did not immunise with MMR made a “conscious decision” not to immunise. Conclusions Although MMR uptake in this cohort is high, a substantial proportion of children remain susceptible to avoidable infection, largely because parents consciously decide not to immunise. Social differentials in uptake could be used to inform targeted interventions to promote uptake. 相似文献
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J J Bedford R A Smith M Thomas J P Leader 《Comparative biochemistry and physiology. A, Comparative physiology》1991,100(1):145-149
1. The process of cell volume readjustment, during adaptation to salinity changes, in muscle fibres of the euryhaline New Zealand shore crab, Hemigrapsus edwardsi, involve large changes in the amounts of free amino acid. 2. These are taurine, proline, alanine, arginine, glutamic acid, glycine and serine. 3. These changes may be quantified by High Performance Liquid Chromatography, and qualitatively demonstrated by proton nuclear magnetic resonance spectroscopy. 相似文献
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The current study involves an investigation of the possible neurotransmitter systems involved in the ability of exogenously administered sincalide (cholecystokinin octapeptide, CCK-8) to suppress feeding. Male rats previously trained to obtain food either during a daily 3-hr session, or conditioned to obtain food pellets on a fixed-ratio or fixed-interval schedule of reinforcement, were treated IP with CCK-8, following pretreatment with representative drugs of several pharmacological classes. Pretreatment with phenoxybenzamine, tolazoline, yohimbine, morphine, haloperidol or picrotoxin reduced the efficacy of CCK-8. However, pretreatment with naloxone or clonidine potentiated the suppressant action of CCK-8 on feeding. Propranolol, diphenhydramine, cimetidine, atropine, d-amphetamine, fenfluramine or diazepam pretreatment either had no effect or no consistent action in altering the activity of CCK-8. The ability of CCK-8 to suppress feeding was not altered by subacute treatment with the anorectics, d-amphetamine or fenfluramine, using a regimen known to induce tolerance. These data indicate that CCK-8 exerts a different mechanism of action than that of fenfluramine or d-amphetamine, and furthermore, that noradrenergic, dopaminergic, GABAergic or endogenous opioid systems either mediate or can modify the effect of CCK-8 on feeding. 相似文献