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11.
Background: Low energy availability results in physiological adaptations which contribute to unfavourable health outcomes. Little information exists on perceptions of nutritional advice to eat more food to maintain health and enhance performance. The aim of this study was to explore athletes’ and coaches’ perceptions towards advice to athletes to eat larger than their current quantities of food and to explore how nutritionists could deliver this advice. Methods: Semi-structured interviews (~20 min in length) were conducted using online communication technology, audio-recorded, and transcribed verbatim. The interview explored perceptions of the nutritional advice provided, its role in health and performance, and the challenges to eating larger amounts of food. Data were analysed using NVIVO 1.2 using an inductive thematic approach. Results: Nine elite athletes (female = 6; males = 3) and nine high-performance coaches (female = 3; male = 6) completed the semi-structured interviews. Athletes reported improved training consistency, fewer injuries and illnesses, and improved resilience when consuming adequate energy and nutrients to meet their needs. Lack of time and meal preparation difficulties were the main challenges faced to fuelling. Conclusions: Although education about under-fuelling is important, motivating, enabling, and supporting athletes to change behaviour is pivotal to increasing athlete self-awareness and to make long-term nutritional changes.  相似文献   
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We studied 1250 primiparous women with a singleton pregnancy, gestational age at delivery of 37-42 weeks, with a single live fetus, vertex presentation whose first and second stages of labour were managed according to strict criteria for the active management of labour. 568 (45%) received epidural analgesia (bupivacaine 0.25%) during labour, and the other 682 (55%) received either Entonox, pethidine or no analgesia. The spontaneous vaginal delivery rate in the epidural group was 67% (95% confidence interval [CI] 63-71%), lower than that in the non-epidural group (87%, 95% CI 84-90%). All instrumental delivery rates were higher in the epidural group. However, the rotational forceps rate in the epidural group (2.5%, 95% CI 1.4-4.1%) was only marginally higher than in the non-epidural group (0.9%, 95% CI 0.3-1.9%). Women who were induced were more likely to request an epidural (56%: 95% CI 50-61%) than those with spontaneous onset of labour (41%: 95% CI 38-45%). Whether labour was spontaneous or induced, a higher proportion of women who received epidural required oxytocin augmentation. The effects of combinations of epidural analgesia, the need for oxytocin augmentation and induction of labour on mode of delivery were additive. This preliminary study suggests that a high rate of spontaneous vaginal delivery can be achieved with epidural analgesia when labour is actively managed.  相似文献   
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This year's CPT code revisions were supposed to eliminate problems resulting from codes not keeping pace with lab technology, but errors in the revisions have provided new thorns equally capable of drawing blood. Here's how not to get stuck.  相似文献   
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Summary In this study we retrospectively reviewed results of the first 9 days of treatment with pamidronate at doses of 30 mg (n=13), 45 mg (n=9), and 90 mg (n=13) in an attempt to see what factors influenced the response of serum calcium to pamidronate.The nadir of serum calcium obtained post treatment was correlated with pretreatment levels of nephrogenous cyclic adenosine monophosphate (NcAMP), the renal tubular threshold for phosphate reabsorption (TmPO4), and the renal tubular threshold for calcium reabsorption (TmCa). Using the post treatment serum calcium levels, patients were divided into good and poor responders depending on whether a normal serum calcium was obtained.Pretreatment NcAMP was significantly correlated with the magnitude of the response of serum calcium (r=0.45, P=0.0001). Pretreatment NcAMP was significantly higher in the poor responders (mean±SEM): 65.0±9.4 nmol/liter GF (poor responders) versus 29.6±6.3 (good responders), P=0.004. NcAMP as a predictor of the acute response of serum calcium showed a sensitivity of 93% and a specificity of 72%. Pretreatment TmPO4 was negatively correlated with the serum calcium response post treatment (r=-0.41, P=0.003). However, though TmPO4 tended to be lower in the poor responders, this was not statistically significant [0.65 mmol/liter GF±0.09 (poor responders) versus 0.76 mmol/liter GF±0.06 (good responders)]. As a predictor of the acute response of serum calcium, TmPO4 was less good with a sensitivity of 70% and specificity of 58%. No significant correlation was present between TmCa and the serum calcium response. A significant negative correlation was evident between NcAMP and TmPO4 (r=-0.35, P=0.003), however, no significant correlation was evident between NcAMP and TmCa or TmPO4 and TmCa.These results suggest that in a hypercalcemic patient where evidence exists for the presence in circulation of a factor with PTH-like activity (i.e., NcAMP is elevated or TmPO4 is low) the response of serum calcium to pamidronate is less good. NcAMP would appear to be a useful predictor of the response of serum calcium, whereas TmPO4 is less discriminating.  相似文献   
15.
Monette  FC; Holden  SA 《Blood》1982,60(2):527-530
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells.  相似文献   
16.
Twenty-four patients with angiomas of the thoraco-lumbo-sacral region of the spinal cord, which characteristically occur in elderly men and are situated on the dorsum of the cord, were subjected to surgery after diagnosis by selective arteriography. It is suggested that in this variety of angioma the operation produced its effect by eliminating the raised pressure in the venous and capillary vessels within the spinal cord. There was no evidence of an arterial "steal." In all cases, followed up for a mean of five years, progression of neurological symptoms was arrested but, apart from motor disability and pain, any improvement among this already seriously disabled group was small. Diagnosis in the early stages is difficult but the history of mechanical factors exacerbating the symptoms and which occur in the majority of patients should suggest the presence of such a lesion and indicate the need for myelography. Any improvement in results can only come from greater awareness of the condition leading to earlier diagnosis and operation.  相似文献   
17.
Behavioral sensitization, the progressive and enduring enhancement of certain behaviors following repetitive drug use, is mediated in part by dopaminergic pathways. Increased locomotor response to drug treatment, a sensitizable behavior, is modulated by an opposing balance of dopamine receptor subtypes, with D1/D2 dopamine receptor stimulation increasing and D3 dopamine receptor activation inhibiting amphetamine-induced locomotion. We hypothesize that tolerance of D3 receptor locomotor inhibition contributes to behavioral sensitization. In order to test the hypothesis that expression of behavioral sensitization results in part from release of D3 receptor-mediated inhibition, thereby resulting in decreased response to D3 receptor agonists, we examined the effect of repetitive amphetamine administration on the behavioral response to the D3 receptor preferring agonists 7-OH-DPAT and PD 128907. D3-selective effects have recently been described for both drugs at a low dose. At 1 week following completion of a repetitive treatment regimen, amphetamine-pretreated rats displayed a decreased response to D3-selective doses of both 7-OH-DPAT and PD 128907, when compared to animals receiving saline pretreatment. Moreover, in addition to the quantitative alteration in response, there was a change in the inter-relation between response to amphetamine and D3 agonist. A highly significant inverse relation between locomotor inhibitory response to PD 128907 and the locomotor-stimulant response to amphetamine was observed prior to amphetamine treatment. In contrast, 10 days following repetitive amphetamine treatment, the relation between response to PD 128907 and amphetamine was not detected. The observed behavioral alteration could not be accounted for by changes in D3 receptor binding in ventral striatum. These findings suggest a persistent release of D3 receptor-mediated inhibitory influence contributes to the expression of behavioral sensitization to amphetamine.  相似文献   
18.
Behavioral sensitization is a well-studied model of behavioral plasticity mediated at least in part by dopaminergic systems believed to play an important role in several psychiatric conditions. In the rodent, locomotion is regulated by the opposing balance of D3 and D2 receptors, with D2 activation increasing and D3 stimulation inhibiting locomotion. However, receptor occupancy of D3 dopamine receptors is far greater than D2 or D1 occupancy at typical post-stimulant dopamine concentrations. We therefore hypothesized that tolerance of D3 receptor inhibition of locomotion contributes to the development of sensitization. To test this hypothesis, we examined the effect of the D3 receptor antagonist nafadotride on sensitization. As predicted, nafadotride inhibits augmentation of the locomotion response to repetitive amphetamine. This finding is consistent with the proposed model of adaptive down-regulation of D3 dopamine receptor function contributing to the development of behavioral sensitization.  相似文献   
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