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Reduced noradrenaline levels have been reported to occur in the motor cortices of PD patients postmortem. Imaging techniques have recently become available to specifically study noradrenergic terminal function in vivo using PET. The objective of this study was to evaluate cortical 11C‐MeNER binding in PD patients. Thirty PD patients and 12 healthy control subjects comparable in age, sex, and cognitive performance underwent PET imaging with 11C‐MeNER, a specific ligand of the noradrenaline transporter. Cortical noradrenaline transporter binding was compared at a voxel level using Statistical Parametric Mapping, whereas cortical thickness was assessed using FreeSurfer software with MRI. PD patients showed reduced 11C‐MeNER binding in the primary motor cortex unrelated to cortical thickness; other cortical regions did not differ between groups. In a subgroup analysis, patients with higher Hoehn & Yahr stage exhibited more pronounced 11C‐MeNER binding reductions. Loss of cortical noradrenergic projections to the primary motor cortex occurs in PD associated with disease stage. © 2018 International Parkinson and Movement Disorder Society  相似文献   
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In cystic fibrosis (CF) lung function testing is a means of monitoring progression of lung disease. The preschool years have often been referred to as the “silent years” due to the previous lack suitable measures of lung function testing in this age group. This review outlines the various techniques of lung function testing in preschool children with CF in the clinical setting. This includes measures requiring tidal breathing including the forced oscillation technique, the interrupter technique, plethysmography, and multiple breath washout, as well as spirometry that requires respiratory maneuvers. We describe the feasibility and variability of different lung function methods used in preschoolers and report measurements made during tidal breathing have greater feasibility, although greater variability compared to spirometry. We also report associations with lung function and markers of CF lung disease. In the preschool age group measurements made during tidal breathing may be more appropriate in the clinic setting than those that require a higher degree of cooperation and specific respiratory maneuvers.maneuvers. Pediatr Pulmonol. 2010; 45:419–433. © 2010 Wiley‐Liss, Inc.  相似文献   
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Background: Enteral feed intolerance occurs frequently in critically ill patients and can be associated with adverse outcomes. “Energy‐dense formulae” (ie, >1 kcal/mL) are often prescribed to critically ill patients to reduce administered volume and are presumed to maintain or increase calorie delivery. The aim of this study was to compare gastric emptying of standard and energy‐dense formulae in critically ill patients. Methods: In a retrospective comparison of 2 studies, data were analyzed from 2 groups of patients that received a radiolabeled 100‐mL “meal” containing either standard calories (1 kcal/mL) or concentrated calories (energy‐dense formulae; 2 kcal/mL). Gastric emptying was measured using a scintigraphic technique. Radioisotope data were collected for 4 hours and gastric emptying quantified. Data are presented as mean ± SE or median [interquartile range] as appropriate. Results: Forty patients were studied (n = 18, energy‐dense formulae; n = 22, standard). Groups were well matched in terms of demographics. However, patients in the energy‐dense formula group were studied earlier in their intensive care unit admission (P = .02) and had a greater proportion requiring inotropes (P = .002). A similar amount of calories emptied out of the stomach per unit time (P = .57), but in patients receiving energy‐dense formulae, a greater volume of meal was retained in the stomach (P = .045), consistent with slower gastric emptying. Conclusions: In critically ill patients, the administration of the same volume of a concentrated enteral nutrition formula may not result in the delivery of more calories to the small intestine over time because gastric emptying is slowed.  相似文献   
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Objective

infants of women with diabetes in pregnancy are at increased risk of hypoglycaemia. If the infant's blood glucose is low and the mother is unable to breast feed/provide sufficient expressed breast milk, infants are often given formula. Some hospitals encourage women with diabetes to express breast milk before birth. However, there is limited evidence for this practice, including its impact on labour and birth, e.g. causing premature birth may be a concern. A pilot study was undertaken to establish the feasibility of conducting an adequately powered randomised controlled trial to evaluate this practice.

Design

consecutive eligible women with pre-existing or gestational diabetes (requiring insulin), planning to breast feed and attending the study hospital were offered participation. Inclusion criteria: 34-36 weeks of gestation; singleton pregnancy; cephalic presentation; and able to speak, read and write in English. Exclusion criteria: history of spontaneous preterm birth, antepartum haemorrhage, placenta praevia and suspected fetal compromise. Women were encouraged to express colostrum twice a day from 36 weeks of gestation, and advised how to store the colostrum, which was frozen for their infant's use after birth. They were asked to keep a diary documenting their expressing. Data: demographic questionnaire, telephone interview at six and 12 weeks postpartum and medical record data.

Setting

a public, tertiary, women's hospital in Melbourne, Australia.

Participants

43 women with diabetes in pregnancy (requiring insulin).

Findings

cardiotocographs were undertaken after the first expressing episode and none of the infants showed any sign of fetal compromise. Forty per cent of infants received formula in the 24 hours postpartum. The proportion of infants receiving any breast milk at six weeks was 90%, and this decreased to 75% at 12 weeks. No women showed evidence of hypoglycaemia post expressing. The intervention was positively received by most women; 95% said that they would express antenatally again if the practice proved to be beneficial. The amount of colostrum varied according to the number of expressions, the length of time in the study and the time spent expressing, with a median of 14 days expressing and 39.6 ml of colostrum obtained.

Key conclusions

the small number of women in this pilot was not an adequate number to examine safety or efficacy, but this study does provide evidence that it would be feasible and desirable to conduct a randomised controlled trial of antenatal milk expressing for women with diabetes requiring insulin in pregnancy.

Implications for practice

it is important that this widespread practice undergoes rigorous evaluation to assess both efficacy and safety. Until such evidence is available, the authors suggest that the routine encouragement of antenatal milk expressing in women with diabetes in pregnancy should cease.  相似文献   
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