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101.
BACKGROUND: This study evaluated the effects of severe undernutrition during adolescence and subsequent colon carcinoma risk. METHODS: The authors evaluated The Netherlands Cohort Study on Diet and Cancer (NLCS) among 62,573 women and 58,279 men aged 55-69 years at baseline. Information on diet and risk factors was collected by questionnaire in 1986. Additional information was collected concerning residence during the hunger winter (1944-1945), the World War II years (1940-1944), and father's employment status during the economic depression of 1932-1940, which were used as indicators of exposure. After 7.3 years of follow-up, 807 colon carcinoma cases (388 females and 419 males) were available for analysis. RESULTS: Multivariate analysis showed that both men and women who had lived in a western city in 1944-1945 had a decreased colon carcinoma risk (men: relative risk [RR] = 0.85, 95% confidence interval [CI] = 0.62-1.16; women: RR = 0.80, 95% CI = 0.59-1.09). No association between colon carcinoma risk and urban versus rural residence was found during the war years (1940-1944). Having an unemployed father during the economic depression (1932-1940) was also associated with a small decrease in colon carcinoma risk for men (RR = 0.90, 95% CI =0.62-1.31) and women (RR = 0.75, 95% CI 0.49-1.14). In subgroup analyses, a decreased colon carcinoma risk for men and women who were in their adolescent growth spurt and living in a western city during the hunger winter of 1944-1945 was noted (men: RR = 0.72, 95% CI = 0.31-1.65; women: RR = 0.88, 95% CI = 0.40-1.96). No associations were statistically significant because of the limited study size. CONCLUSIONS: In the current study, a weak inverse relation was found between energy restriction early in life and subsequent colon carcinoma risk for men and women. However, these findings need replication in a larger study. 相似文献
102.
氧瓶燃烧-紫外分光光度法测定硒灵胶囊中硒的含量 总被引:3,自引:0,他引:3
目的:控制本品中硒的含量。方法:采用氧瓶燃烧法使本样品中的主要成份硒酯多糖成四阶硒离子,并与2,3-二氨基萘(DNA)络合生成4,5-苄苯并硒二唑,然后采用紫外分光光度法测定其含量,结果:硒的浓度在0.2~2.0μg/ml之间线性范围良好。结论:该法具有简便,快速,准确的优点。 相似文献
103.
Elevated levels of intact parathyroid hormone (iPTH) are not uncommon after renal transplantation, and this disturbance may affect renal allograft function. This study investigated whether iPTH levels were related to histopathological findings of acute rejection in kidney graft biopsies. Thirty-eight renal transplant recipients (29 males, nine females; mean age 29.5±10.3years) were studied. Renal allograft biopsy was performed in each case to investigate increased creatinine levels. Lymphocyte and macrophage infiltration of the interstitium was evaluated immunohistochemically with monoclonal antibodies to CD3 and CD68. Expression of HLA-DR and fibronectin were also studied. The proportion of interstitial cell staining was graded semiquantitatively. Serum calcium, phosphorus and iPTH levels before and after the renal transplantation were compared. Patients were grouped according to their stabilized iPTH levels at 3 months post-transplantation. Group I ( n =13) exhibited persistently elevated iPTH levels (levels elevated since surgery), and Group II ( n =25) showed persistently low-normal iPTH levels. The mean age of the Group I patients was significantly lower, and their serum calcium levels post-transplantation were significantly higher than those in Group II ( P =0.02 and P =0.03, respectively). Persistent elevation of iPTH was strongly associated with interstitial T-cell density, macrophage density, and glomerular fibronectin expression in the renal allograft biopsies ( P <0.05). Also, the time to fibrosis was significantly shorter in Group I ( P =0.02). The study revealed that PTH has a potent immunomodulatory effect, and that persistent hyperparathyroidism has a significant impact on renal allograft outcome. The data indicate that the serum iPTH level is a valuable indicator of immune response, and that regular monitoring of serum iPTH levels is essential after renal transplantation. 相似文献
104.
LH Diamond 《American journal of kidney diseases》1999,33(1):208-210
Making appropriate coverage decisions has the potential of impacting patient outcomes. In both the public and private sectors, great diversity exists in the methodology and process used to make coverage decisions. Because definitional issues are important, they are described in this article. The underpinning of coverage decisions are a commitment to certain methodological principles, including embracing evidence-based medicine. The role of the federal government and local entities in regard to evidence production and process as well as methodology used to formulate policy decisions is complex and requires resolution. A temporary coverage decision can be a helpful tool when no consensus exists. 相似文献
105.
The Dutch famine birth cohort study: design, validation of exposure, and selected characteristics of subjects after 43 years follow-up 总被引:2,自引:0,他引:2
L. H. Lumey † ‡ § A. C. J. Ravelli‡ L. G. Wiessing J. G. Koppe† P. E. Treffers Z. A. Stein§ ¶ 《Paediatric and perinatal epidemiology》1993,7(4):354-367
Summary. A historical birth cohort study of 1116 women born between August 1 1944 and April 15 1946 in the Wilhelmina Gasthuis hospital in Amsterdam, the Netherlands, was set up to study the short- and long-term effects of a limited period of extreme nutritional deprivation in the winter of 1944–1945 in the Western Netherlands. The degree of food deprivation is evidenced by a dramatic decline in third trimester pregnancy weight gain and infant birthweight. All women were traced and 84% (683/813) of survivors presently resident in the Netherlands agreed to be interviewed in their homes. There were no differences in characteristics at birth between interviewed and uninterviewed survivors. The women who were interviewed had 1299 offspring and were able to recall birthweight of all of them. Additional birthweight information from hospital and well-baby clinic (WBC) records is available for about half of the offspring. Since the famine was imposed on the entire population of a well-defined area, whose opportunities to obtain food elsewhere were severely restricted, and the women from this hospital cohort were predominantly lower middle class, the relationship between fetal nutrition and subsequent health outcomes in this cohort is not likely to be confounded by unmeasured attributes related to social class. In addition, selective losses to follow-up could be excluded, which makes the Dutch famine birth cohort a valuable resource for future studies in perinatal epidemiology. 相似文献
106.
Esophageal leiomyomatosis 总被引:1,自引:0,他引:1
107.
108.
Exposure to famine during gestation, size at birth, and blood pressure at age 59 y: evidence from the dutch famine 总被引:3,自引:0,他引:3
Stein AD Zybert PA van der Pal-de Bruin K Lumey LH 《European journal of epidemiology》2006,21(10):759-765
We compared blood pressure of individuals (mean age 59 y) born in western Holland between January 1945 and March 1946 (mothers exposed to the Dutch Famine before or during gestation; n = 359) to blood pressure of unexposed individuals born before or conceived after the famine (n = 299) or same-sex siblings of subjects in series 1 or 2 (n = 313). Mean (SD) systolic and diastolic blood pressure were 140.3 (20.3) and 85.8 (11.0) mmHg, respectively; prevalence of hypertension (prior diagnosis of hypertension or with measured systolic/diastolic blood pressure above 140/90 mmHg) was 61.8%. Birth weight was inversely related to systolic (−4.14 mmHg per kg; 95% confidence interval (CI) −7.24, −1.03; p < 0.01) and diastolic (−2.09 mmHg per kg; 95% CI −3.77, −0.41; p < 0.05) blood pressure and to the prevalence of hypertension (odds ratio 0.67 per kg, 95% CI: 0.49, 0.93) (all age- and sex-adjusted). Any famine exposure of at least 10 weeks duration was associated with elevated systolic (2.77 mmHg; 95% CI 0.25, 5.30; p < 0.05) and diastolic (1.27 mmHg; 95% CI −0.13, 2.66; p = 0.08) blood pressure and with hypertension prevalence (odds ratio 1.44; 95% CI 1.04, 2.00; p < 0.05) in age- and sex-adjusted models. Exposure to famine during gestation may predispose to the development of hypertension in middle age. 相似文献
109.
A new system for telecommunication of radiographic images using readily available telephone transmission circuitry is described. The resulting video images were satisfactory for accurate interpretation in 80% of the cases tested. The system is moderately priced and has facilitated maintenance of radiodiagnostic interpretive services at a satellite office form the central hospital location. 相似文献
110.
DNA甲基化异常是胃癌发生的重要机制之一,为了能尽早发现并纠正DNA甲基化异常,阻止胃癌的发生,胃黏膜癌前病变中DNA甲基化状态的研究日益受到重视.众多研究表明,胃黏膜癌前病变中多种基因中存在甲基化异常,而且基因的甲基化异常程度与年龄、性别有关,还与胃黏膜上皮细胞是否存在活动性炎症、肠化及幽门螺杆菌感染有关.叶酸缺乏可导致DNA甲基化的紊乱和DNA修复机制效率的减弱, 叶酸摄入量不足患胃癌的相对危险度增高;胃黏膜癌前病变患者体内叶酸不足,黏膜细胞总基因组DNA甲基化水平下降;经叶酸治疗后,体内叶酸升高,黏膜细胞总基因组DNA 甲基化水平上升,异型增生、肠上皮化生明显改善.因此,叶酸缺乏与胃黏膜癌前病变的发生、发展有关,及时纠正叶酸不足,可逆转胃黏膜的病理改变,减少胃癌的发生. 相似文献