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101.
102.
Summary Oxidized wax blends with respectively HDPE, LDPE and LLDPE were investigated using CRYSTAF and SEC–FTIR in order to determine the possibility and extent of co–crystallization of the wax with each of these polyethylenes. CRYSTAF shows very little or no co–crystallization of wax with HDPE and LDPE, while there is a strong indication of co–crystallization in the case of LLDPE. SEC-FTIR analyses show co–elution of wax with LLDPE, indicating some chemical interaction between the oxidized wax and LLDPE.  相似文献   
103.
Daily urinary adrenalin, noradrenaline, dopamine excretion and blood levels of serotonin were measured over the course of the cycle in 8 healthy girls and in 52 patients with the juvenile hypothalamic syndrome in the acute and chronic stages. These parameters were found virtually the same in healthy girls and in those suffering from the hypothalamic syndrome in the course of the cycle or in patients during the acute and chronic stages of the condition. Urinary catecholamine excretion and blood serotonin levels were increased by 1.5-2 times in the acute stage of the syndrome and somewhat reduced in the chronic stage; this appears to be due to reduced activity of the sympathoadrenal system in the course of disease progress.  相似文献   
104.
We evaluated factors associated with mortality among a cohort of malnourished children with persistent diarrhoea (PD) admitted for nutritional rehabilitation with a defined rice-lentil (Khitchri) and yoghurt diet. Of 302 children consecutively admitted with PD, 13 (4 per cent) died, mostly (62 per cent) within 72 h of admission. Univariate analysis of risk factors at admission associated with mortality indicated significantly increased risk of death with severe stunting [relative risk (RR) 3.1, 95 per cent confidence interval (CI) 1.1-9.0], hypoalbuminaemia (RR 4.3, 95 per cent CI 1.5-12.3), stool frequency > 12/day (RR 6.0, 96 per cent CI 2.0-17.6), stool volume > 100 g/kg/day (RR 10.7, 95 per cent CI 3.0-37.6) and severe dehydration (RR 7.5, 95 per cent CI 2.6-21.8). Children who died also had comparatively shorter duration of diarrhoea at admission, and were also associated with higher rate of bacteremia at admission (Fisher's exact test P < 0.01). The logistic regression model evaluating multivariate risk of mortality identified weight-for-age z-score and sepsis as significant risk factors. Our data suggest that severe malnutrition and sepsis are associated with significantly increased risk of mortality in children with PD. Stringent screening for infections and recognition of subgroups with severe malnutrition and severe diarrhoea may improve screening and case management strategies for this disorder.  相似文献   
105.
Abstract

This paper refers to a previous comment by J. R. Eyre on an earlier paper of ours in which we tried to make the best possible use of 4-channel AVHRR/1 data for the determination of sea surface temperatures in situations where data from the 5-channel AVHRR/2 were not available. Here we clarify certain points regarding the philosophy of our earlier paper and also respond to some specific points made by Eyre.  相似文献   
106.
Use of synthetic oligonucleotides for inhibition of factor NF-kappa B   总被引:1,自引:0,他引:1  
The effect of the proportion of clover in the diet (200, 500 or 800 g/kg total dry matter (DM) on milk production of cows housed indoors and fed on a mixture of perennial rye-grass and white clover was measured in mid (Expt I) and late (Expt II) lactation. Higher clover contents increased the nutritive value of the diets, resulting in increased energy and protein intakes. DM intakes of cows offered 500 or 800 g clover/kg DM diets ad lib. (Expt I and Expt II, Period 1) were not significantly different but were 11-17% greater (P < 0.05) than intakes of cows fed on 200 g clover/kg total DM diets. Cows offered restricted allowances (Expt II, Period 2) had similar intakes irrespective of diet. In Expt I cows fed on 500 or 800 g clover/kg DM diets ad lib. produced 30 or 33% respectively more milk (P < 0.05) than cows fed on 200 g clover/kg total DM diets. During Expt II, Period 1, cows fed on 500 or 800 g clover/kg DM diets ad lib. produced 18 or 16% more milk (P < 0.05) respectively than cows given 200 g clover/kg total DM diets. In both these experiments the increased milk yields were due to increased intake and the higher nutritive value of the high clover diets. There was no difference in the feed conversion efficiencies of cows if maintenance energy requirements were taken into account. However, cows on restricted allowances (Expt II, Period 2) showed no significant difference in milk yield, indicating that the effect of increased nutritive value was very slight. There were no consistent effects on milk fat, protein or lactose concentrations. Concentrations of blood and milk urea increased as the clover content of the diet increased (Expt 1 only), and this was associated with increased milk non-protein N and a decreased ratio of casein N: total N. Both trials indicated an optimum clover content in the diet for milk production of 600-700 g/kg total DM.  相似文献   
107.
Mitochondrial creatine kinases form octameric structures composed of four active and stable dimers. Octamer formation has been postulated to occur via interaction of the charged amino acids in the N-terminal peptide of the mature enzyme. We altered codons for charged amino acids in the N-terminal region of mature sarcomeric mitochondrial creatine kinase (sMtCK) to those encoding neutral amino acids. Transfection of normal sMtCK cDNA or those with the mutations R42G, E43G/H45G, and K46G into rat neonatal cardiomyocytes resulted in enzymatically active sMtCK expression in all. After hypoosmotic treatment of isolated mitochondria, mitochondrial inner membrane-associated and soluble sMtCK from the intermembranous space were measured. The R42G and E43G/H45G double mutation caused destabilization of the octameric structure of sMtCK and a profound reduction in binding of sMtCK to the inner mitochondrial membrane. The other mutant sMtCK proteins had modest reductions in binding. Creatine-stimulated respiration was markedly reduced in mitochondria isolated from cells transfected with the R42G mutant cDNA as compared with those transfected with normal sMtCK cDNA. We conclude that neutralization of charges in N-terminal peptide resulted in destabilization of octamer structure of sMtCK. Thus, charged amino acids at the N-terminal moiety of mature sMtCK are essential for octamer formation, binding of sMtCK with inner mitochondrial membrane, and coupling of sMtCK to oxidative phosphorylation.  相似文献   
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109.
BACKGROUND: We evaluated whether therapy designed to eradicate Helicobacter pylori infection resulted in a reduction in rebleeding in patients with peptic ulcer disease. Patients presenting because of major upper gastrointestinal hemorrhage from peptic ulcer and whose ulcers healed in a study in which they were randomized to receive ranitidine alone or triple therapy plus ranitidine were followed up regularly with endoscopy. No maintenance anti-ulcer therapy was given after ulcer healing. METHODS: Patients received ranitidine, 300 mg, or ranitidine plus triple therapy. Triple therapy consisted of tetracycline, 2 g; metronidazole, 750 mg; and bismuth subsalicylate, 5 or 8 tablets (151 mg bismuth per tablet), and was administered for the first 2 weeks of treatment; ranitidine therapy was continued until the ulcer had healed or 16 weeks had elapsed. After ulcer healing, no maintenance antiulcer therapy was given. Development of ulcer recurrence with or without recurrent upper gastrointestinal bleeding was evaluated. RESULTS: Thirty-one patients with major upper gastrointestinal bleeding from peptic ulcer were studied; 17 received triple therapy and 14 ranitidine alone. Major rebleeding occurred significantly (p = 0.031) more often in those in the ranitidine group (28.6%), compared with none (0%) in the triple therapy group. CONCLUSION: Eradication of H. pylori infection reduces the rate of ulcer recurrence and rebleeding in complicated ulcer disease.  相似文献   
110.
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