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A deficiency of total energy or of one or more essential nutrients, including vitamins A, B6, B12, C, and E, folic acid, zinc, iron, copper, selenium, essential amino acids and essential fatty acids, will impair immune function and increase susceptibility of the host to infectious pathogens. This is most likely because these nutrients are involved in the molecular and cellular responses to challenge of the immune system. Providing these nutrients to deficient individuals restores immune function and improves resistance to infection. Thus, appropriate nutrition is required in order for the host to maintain adequate immune defences towards bacteria, viruses, fungi, parasites and tumour celîs. Although the intakes of several nutrients which result in greatest enhancement of immune function appear to be greater than recommended intakes, excess intake of certain nutrients also impairs immune responses. Some nutrients (e.g. glutamine, arginine) may become limiting in critical illness and there is mounting evidence that provision of these will aid patient recovery. 相似文献
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Protein turnover rates in sick, premature neonates during the first few days of life. 总被引:1,自引:0,他引:1
Rates of protein turnover were measured in 19 infants during the first few days of life while they were receiving i.v. glucose. The technique consisted of a continuous i.v. infusion of L-[1-13C]leucine to measure whole body leucine flux and determination of total urinary nitrogen excretion to assess leucine oxidation rates. Subsequent to each of the studies, the decision to start total parenteral nutrition (TPN) was made by the clinician concerned, with the result that seven infants did not start TPN and 12 did. There were significantly greater urinary nitrogen excretion (p less than 0.001) and lower rates of whole body protein synthesis (p = 0.024) and breakdown (p = 0.015) in those who did start TPN compared with those who did not. The marked difference in nitrogen excretion between the two groups suggests that this could be a useful determinant for deciding which neonate should start TPN. 相似文献
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目的:对临床确诊糖尿病患同时测定血清葡萄糖(Glu)及糖化血清蛋白(GSP)的含量,观察二的关系,以及糖化血清蛋白水平对于评价近期(2—3周)糖尿病患血糖在体内变化的临床意义进行了观察。方法:血清葡萄糖、糖化血清蛋白测定均采用酶法测定。结果:178例糖尿病患Glu、GSP均正常3l例占17.4%;Glu、GSP均增高107例占60.1%;Glu正常、GSP增高15例占8.43%;Glu增高、GSP正常25例占14%。结论:糖化血清蛋白的含量不受即时血糖的影响,二的变化不成比例性,对评价糖尿病患2~3周病情的控制是一项灵敏可靠的指标,尤其对于住院病人的治疗与监控有一定的意义。 相似文献
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Antagonists of the N-methyl-D-aspartate (NMDA) type of excitatory amino acid (EAA) receptors blocked cocaine-induced stereotypy, locomotor stimulation and convulsions. These effects in general appear to involve selectively NMDA type of receptors. The results suggest that NMDA-activated systems are an integral component in the reaction sequences involved in the expression of several behavioral effects of cocaine. 相似文献
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Carlos Calderón Rafael Rotaeche Arritxu Etxebarria Mercé Marzo Rosa Rico Marta Barandiaran 《BMC health services research》2006,6(1):138-11
Background
The GRADE method represents a new approach to grading the quality of evidence and strength of recommendations in the preparation of Clinical Practice Guidelines (CPG). In the context of a pilot study to assess the implementability of the system in Spain, we considered it relevant to gain an insight into the significance of the perceptions and attitudes expressed by the actual experts participating in the system try-out. 相似文献9.
G Barzen C Schubert W Richter D Calder M B?rwald H Eichst?dt R Felix 《Strahlentherapie und Onkologie》1992,168(12):732-737
We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up. 相似文献
10.
S. Loughran N. Calder F.B. MacGregor P. Carding K. MacKenzie 《Clinical otolaryngology》2005,30(1):42-47
Objectives: To assess whether proposed voice and quality of life (QoL) outcome measures were likely to be acceptable to patients previously treated for early glottic cancer by either radiotherapy or endoscopic resection, as well as looking for differences in QoL and voice between treatments. Design: Questionnaire‐based cohort study. Setting: Secondary care, three centres. Participants: All patients treated for T1a or in situ glottic carcinoma between 1997 and 2003. Fifty‐three patients were identified; those who had undergone salvage surgery or radiotherapy were excluded. A proportion refused to participate or could not be contacted and two patients had died of unrelated causes. Thirty‐six patients completed the trial with 18 from each treatment arm. Main outcome measures: Quality of voice as assessed by three questionnaires, Voice Handicap Index (VHI), Vocal Performance Questionnaire (VPQ), Voice Symptom Score (VoiSS) and perceptual analysis of voice by Grade, Roughness, Breathiness, Asthenia and Strained (GRBAS) assessment of vocal recordings. Quality of life as assessed by the Hospital Anxiety and Depression Scale (HADS), University of Washington Quality of Life Questionnaire (UW‐QoL), and the Functional Assessment of Cancer Therapy (FACT) questionnaire. Results: All patients included in the trial were able to complete the questionnaires; however, 19% required assistance of some kind. GRBAS assessment showed no difference between groups for any criteria. All QoL questionnaires gave equivalent good scores. All of the voice questionnaires showed no statistical difference between groups except for the emotional subscale of the VoiSS which showed a significantly better score for the radiotherapy arm (P = 0.04). Conclusion: All outcome measures were applicable and acceptable to the patient group. Overall QoL and voice appears similar despite treatment arm, apart from the emotional subscale of the VoiSS. A randomized controlled trial is required to further assess this question. 相似文献