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Norway has formed a policy on infant feeding, expressed as dietary allowances and guidelines concerning food intake. In a longitudinal and prospective study of health and development during infancy, the feeding patterns of 217 Norwegian infants were followed in order to evaluate the policy. The findings indicated that prevailing guidelines were largely followed by the parents. Forty-five per cent still got breastmilk at 6 months. Solid foods were usually introduced around 4-5 months, iron-enriched porridge being commonly used. At 10 months 91 per cent were given bread. The nutrient intakes at 10 months were mainly in accordance with the recommendations. The quality of the diet seemed to diminish somewhat when sandwiches replaced porridge. More emphasis should be put upon toddlers' diet in counselling the parents.  相似文献   
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The present study, using robotized DNA isolation and quantitative PCR based on the Neisseria meningitidis-specific capsular transport A gene, demonstrates the ease, rapidity, specificity, and sensitivity of quantifying neisserial DNA in plasma (n = 65) and cerebrospinal fluid (CSF) (n = 12) from patients with systemic meningococcal disease. We found a close correlation between the levels of neisserial DNA and lipopolysaccharides in plasma (r = 0.905) and in CSF (r = 0.964). The median concentration of neisserial DNA in plasma in 23 patients with persistent shock was 2 x 10(7) copies/ml, versus <10(3) copies/ml in 42 nonshock patients. Furthermore, quantitative PCR made possible estimates of the total number of meningococci in plasma, as opposed to conventional blood cultures, suggesting about 1,000 dead meningococci for every viable bacterium. Finally, with logistic regression analyses, neisserial DNA may predict a patient's disease severity and outcome at hospital admission. The number of meningococci in plasma and CSF appears to be the main determinant of the lipopolysaccharide levels, clinical presentation, and outcome.  相似文献   
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Mechanisms of mild glyceryl trinitrate tolerance in rats (transdermal application; 15 mg/day/2 days) were examined in isolated aortic rings contracted with phenylephrine. Tolerance to glyceryl trinitrate was comparable in both endothelium-intact and -denuded vessels; the maximum relaxation decreased to 70-80% and the EC50 increased 3-4-fold. There was minimal cross-tolerance to acetylcholine (1.7-fold increase in EC50) and none to sodium nitroprusside. The results suggest that mild tolerance to glyceryl trinitrate in rats is mediated by mechanisms which are predominantly endothelium-independent and which produce little activation of the cellular mechanism responsible for cross-tolerance.  相似文献   
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We have analysed the collagens present in vascular basement membranes isolated from bovine retinal and cerebral microvessels and bovine renal glomeruli, and from the non-vascular basement membrane of bovine lens capsule. These are compared with the collagens produced by cultured bovine retinal microvascular pericytes and lens epithelial cells, and by canine retinal microvascular endothelial cells, in vitro. Biochemical and immunocytochemical analyses indicate that all of the vascular basement membrane preparations have an identical collagenous composition, consisting of the same polypeptides present in lens capsule (primarily type IV collagen), together with other polypeptides that are identified as type I, and a small amount of type III collagen. Identification of the latter is based on two-dimensional gel electrophoresis in the presence and absence of a reducing agent. Immunocytochemical studies, however, demonstrate type I, type IV and some type V collagen in the basement membranes of the isolated microvessels. The cultured microvascular cells produce predominantly type I collagen molecules, but they also produce other collagen peptides that appear to be type IV, and, at least in some experiments, small amounts of type III collagen. The biochemical identification of collagens type I and IV is confirmed by immunocytochemistry. However, results with anti-type I collagen and procollagen antibodies in cultured pericytes vary with antibodies from different sources. The quantities of the type IV peptides produced by the cultured cells also vary in different experiments.  相似文献   
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In the present research article, we have developed solid heterogenous silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts. These catalysts were synthesized by a novel, simple, cheap, clean, and environment friendly method. The physicochemical properties of the prepared catalysts were well studied and characterized by sophisticated spectroscopic techniques such as FTIR, TGA, XRD, EDX, SEM, TEM and BET analysis. The catalyst was utilized in the synthesis of arylimidazole derivatives via green protocols under solvent-free conditions at 70 °C with a higher yield, mild reaction conditions and a short reaction time. The catalyst works superiorly in water as well as in various organic solvents as a reusable and easily recoverable catalyst.

Silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts were developed by a novel, simple, cheap, and environment friendly method and utilized them in the synthesis of arylimidazole derivatives via one pot solvent-free approach.  相似文献   
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