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51.
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   
52.
Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.  相似文献   
53.
戴贵东  王心如 《卫生研究》2003,32(2):159-162
膀胱癌是泌尿外科最常见的恶性肿瘤织一 ,由于复发率较高 ,死亡率逐年上升 ,防止肿瘤发生、发展和侵袭转移是降低膀胱癌高复发率和死亡率的关键。随着人们对膀胱肿瘤发生的分子生物学机制研究的深入 ,相关生物学标志物的相继问世以及某些化学药品和食品防癌作用的发现 ,尤其是癌症化学防治取得的一定的成功 ,使得防止和逆转膀胱肿瘤癌前病变成为可能 ,为此 ,本文对膀胱肿瘤化学防治近年的研究进展进行综述 ,为预防和控制膀胱肿瘤提供指导  相似文献   
54.
Obesity in youth and middle age and risk of colorectal cancer in men   总被引:5,自引:0,他引:5  
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services.  相似文献   
55.
早期肠道营养对烧伤后肠源性高代谢的影响   总被引:9,自引:1,他引:8  
从80年代末起,通过对600只大(豚)鼠、60只兔和60头小香猪所建立的4种烧伤后早期营养的动物模型,以及21例严重烧伤病人对比分析,发现烧伤后早期肠道喂养可改善胃肠道血流供应,减轻肠道缺血再灌流损伤;可维护肠粘膜结构以及吸收、分泌、运动功能,降低门脉、中心静脉血内毒素水平,减少肠道内毒素易位;可降低伤后枯否细胞获得数、吞噬墨汁枯否细胞数和面积,以及其培养上清中肿瘤坏死因子(TNF)量,对伤后枯否细胞的活化有刺激作用;可降低血胰高糖素、皮质醇、儿茶酚胺、TNF、IL-8前列腺素E2(PGE2)等递质的水平,降低高代谢,使烧伤45%成人静息能量消耗(REE)在烧伤后4、8、14d的均值降低28.6%。通过相关分析发现REE与血丙二醛(MDA)、内毒素、分解激素、TNF均呈显著正相关(r=0.7386~0.9922,P<0.05~0.01)。  相似文献   
56.
本研究收集食管癌行食管癌切除胃代食管术病例265例,分为未用深静脉高营养组(NTPN)和深静脉高营养组(TPN)。分别对各组临床资料进行比较分析,结果显示:TPN组葡萄糖供给量(8.37±2.12g/kg/24小时)显著高于NTPN组(2.77±0.71g/kg/24小时)(P<0.01),(0.30±0.14g/kg/小时)P<0.05。吻合口瘘发生率TPN组(2.1%)则显著低于NTPN组(15.2%)P<0.001。结果提示TPN组可明显降低吻合口瘘发生率。作者于TPN促进吻合的愈合,预防吻合口瘘发生的有关机理进行了讨论。  相似文献   
57.
目的:观察应用表皮生长因子(EGF)对全胃肠外营养(TPN)大部小肠切除大鼠残存小肠黏膜的代偿作用。方法:30只大鼠切除80%小肠后分为对照组、常规TPN组、TPN EGF组,观测体重、小肠黏膜形态学改变,流式细胞仪分析肠黏膜细胞增殖活性。结果:术后3组大鼠体重逐渐降低,1周后渐增加。3组间差异无显著性。TPN组小肠肠壁各层均变薄,黏膜萎缩。TPN EGF组肠黏膜厚度、绒毛高度、隐窝深度较TPN组均增加,S期细胞比率系数、增殖指数TPN EGF组较TPN组高,而TPN捐与对照绸差异无昂著件。结论:TPN联合EGF可晟著地增讲肠黏膜的适应性代偿。  相似文献   
58.
目的:评估全肠外营养(TPN)对老年晚期消化系统恶性肿瘤病人生存期的影响。方法:回顾性分析121例老年晚期消化系统恶性肿瘤病人TPN治疗后的生存期。结果:TPN治疗后,患者生存期不同程度延长,为9~126天,平均68.1天,多数在两月左右。结论:TPN可延长老年晚期消化系统恶性肿瘤病人的生存期。  相似文献   
59.
利多卡因用于放射性黏膜损伤所致口腔疼痛的疗效观察   总被引:3,自引:0,他引:3  
目的观察利多卡因稀释液用于放射性黏膜损伤后口腔疼痛的疗效。方法首次诊断和初次治疗的头颈部放疗患者共90例,放射总剂量60—72Cy/30—35次,随机分为对照组44例和观察组46例;对照组患者放疗期间给予饮食指导和静脉营养支持,观察组患者除饮食指导和静脉营养支持以外,在口腔疼痛时和餐前给予利多卡因含漱液20ml含漱;当放射剂量达20、40、60Gy时比较两组患者的口腔疼痛分度状况和体重下降状况;所有资料采用秩和检验。结果观察组在放射剂量20、40、60Gy时,口腔疼痛和体重下降均明显少于对照组。结论利多卡因稀释液含漱能明显缓解放射性黏膜损伤所致的口腔疼痛,进而改善患者的进食和营养状况。  相似文献   
60.
Summary We have compared the effects of two dietary regimens with different macronutrient compositions — a macrobiotic diet and a Western diet — on drug metabolism and plasma lipids in seven healthy volunteers.The macrobiotic diet, high in carbohydrate, low in protein and fat, and devoid of animal food sources, was eaten for a ten day control period, as was the Western diet, high in calories, fat, and protein, as well as animal food sources. We determined the influences of these diets on the clearance of orally administered antipyrine, oxazepam, and methadone, as well as on plasma lipids.There was a statistically significant change in antipyrine clearance as well as in plasma LDL-cholesterol and HDL-cholesterol after the dietary periods. This suggests that the influence of dietary changes may have some effect on the clearance of therapeutic drugs. However, this is not universal and is probably important when the drug is highly dependent on the mixed-function oxidase system.  相似文献   
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