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21.
Prospective study of serum retinol, β-carotene, β-cryptoxanthin, and lutein/zeaxanthin and esophageal and gastric cancers in China 总被引:1,自引:0,他引:1
Abnet CC Qiao YL Dawsey SM Buckman DW Yang CS Blot WJ Dong ZW Taylor PR Mark SD 《Cancer causes & control : CCC》2003,14(7):645-655
Objective: This study examined the relationship between pretrial serum concentrations of retinol, -carotene, -cryptoxanthin, and lutein/zeaxanthin and the subsequent risk of developing esophageal squamous cell carcinoma and gastric cardia or non-cardia adenocarcinoma in subjects selected from a randomized nutritional intervention trial in Linxian, China, a region with epidemic rates of esophageal and gastric cardia cancer. Methods: We used a stratified case–cohort design to select cohort members for inclusion in this study. In all we measured serum concentrations of the above vitamins in 590 esophageal, 395 gastric cardia, and 87 gastric non-cardia case subjects as well as in 1053 control subjects. Relative risks (RRs) were estimated using Cox proportional hazards models. Results: Median values in our cohort were low for serum retinol (33.6 g/dl), -carotene (4.3 g/dl), and -cryptoxanthin (3.5 g/dl) , but were high for lutein/zeaxanthin (40.0 g/dl). Gastric cardia cancer incidence fell 10% for each quartile increase in serum retinol (RR = 0.90, 95% CI = 0.83–0.99). For esophageal cancer, an inverse association with retinol levels was found only in male non-smokers (RR = 0.79 per quartile increase, 95% CI = 0.63–0.99). For gastric non-cardia cancer, an inverse association was limited to subjects 50 years old or younger (RR = 0.58 per quartile, 95% CI = 0.31–0.96). For -cryptoxanthin there was a borderline significant protective association for gastric non-cardia cancer (RR = 0.88 per quartile, 95% CI = 0.76–1.0). In contrast, we found the incidence of gastric non-cardia cancer increased (RR = 1.2 per quartile, 95% CI = 1.0–1.3) with increasing concentration of serum lutein/zeaxanthin. Conclusions: In this population, we found that low retinol and high lutein/zeaxanthin concentrations increased the risks of gastric cardia and gastric non-cardia cancer respectively. We found that there were no strong associations between any of the other analytes and any of the cancer sites. 相似文献
22.
Chih-Cheng Chen Li-Tung Huang You-Lin Tain Hsio-Chi Chaung Chih-Sung Hsieh Hock-Liew Eng Yu-Ching Wei Chun-Yu Yang 《Digestive diseases and sciences》2010,55(10):2831-2837
Background
Cognitive deficiency noted post-liver transplantation might be a result of consequential metabolic derangement before liver transplantation. Long-chain polyunsaturated fatty acids, especially arachidonic acid (AA) and docosahexaenoic acid (DHA), affect the development of the central nervous system and its absorption is influenced by obstructive jaundice. 相似文献23.
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Jing Li Lian-Kun Li Jun-Fei Ma Li-Hui Wei Mayinuer Niyazi Chang-Qing Li Ai-Di Xu Jian-Bin Wang Hao Liang Jerome Belinson You-Lin Qiao 《Vaccine》2009
Infection with the human papillomavirus (HPV) is one of the most common sexually transmitted infections and causes virtually all cervical cancer globally. The recent development of two safe and clinically effective vaccines against HPV is a promising step towards lowering cervical cancer rates in the future. What Chinese women think about HPV and the vaccines remains unknown. We undertook a population-based survey, which was embedded in a cervical cancer screening project and was designed to assess women's knowledge about HPV and their acceptability to the vaccines. We found that only 15.0% of women in our study reported to have ever heard of HPV, and this knowledge differs by rural (9.3%) and metropolitan areas (21.6%) and also by education. Most (84.6%) participants were willing to be vaccinated if HPV vaccine became available to them. The present study documents ways in which women learn about HPV and indicates the potential barriers and success of introducing HPV vaccine to China. 相似文献
26.
Dimethylarginine dimethylaminohydrolase (DDAH) metabolizes asymmetric dimethylarginine to generate L-citrulline and is present in large quantities in the kidney. We present a new study that optimizes the Prescott-Jones colorimetric assay to measure DDAH-dependent L-citrulline generation in kidney homogenates. We found that the removal of urea with urease is necessary since urea also produces a positive reaction. Deproteinization with sulfosalicylic acid was found to be optimal and that protease inhibitors were not necessary. All assays were conducted in phosphate buffer, since other common additives can create false positive and false negative reactions. Arginase or nitric oxide synthase isoenzymes were not found to influence L-citrulline production. Our optimized L-citrulline production assay to measure DDAH activity correlated closely with the direct measure of the rate of asymmetric dimethylarginine consumption. Using this assay, we found that both superoxide and nitric oxide inhibit renal cortical DDAH activity in vitro. 相似文献
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28.
β受体显像剂——碘(131)标记间碘苄胍标记方法的研究 总被引:2,自引:0,他引:2
本文采用亚铜作催化剂,研究了β受体显像剂-碘(13l)标记间碘苄胍的方法。100℃水浴10~15分钟,标记率可达99.9%。和经典的固相催化法相比,它不但快速、方便,而且不存在碘的损失和污染。该法可望将MIBG制成药盒以供临床大量使用。 相似文献
29.
Serial changes in serum gastrin level were detected by radioimmunoassay in 58 lung cancer patients before and after operation. In comparing these tests with those of 40 cases of noncancerous thoracic lesions and 151 normal adults, the serum gastrin from lung cancer patients is significantly higher than that of noncancerous thoracic lesions and normal individuals (P less than 0.01). The gastrin level is closely related to stage of cancer, size of primary tumor, presence of lymph node metastasis, and type of histological classification. The serum gastrin was found to decrease gradually after the removal of the tumor and to return to normal on the 14th postoperative day. Those patients whose serum gastrin level can return to normal on the 14th postoperative day will have a good prognosis; if not, their prognosis will be very poor. These results suggest that serum from patients with lung cancer contains a high concentration of gastrin that can help differentiate benign from malignant thoracic lesions and evaluate prognosis of patients with lung cancer. Therefore, the cause of high serum gastrin in patients with lung cancer is likely due to the gastrin-producing property of the lung cancer cells. 相似文献
30.
Tain Lee I-Chen Tsai Wei-Lin Tsai Min-Chi Chen Ming-Yi Hsue Wan-Chun Liao 《European heart journal》2005,26(17):1805-6; author reply 1806
In their article published online on 19 April 2005, Leschkaet al.1 shared the first experience of the new 64-sliceMSCT. The adequate sample size and evaluation of performancewithout beta-blocker make the article of high reference value.However, we have several questions to the authors. First, the authors mentioned 相似文献