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1.
Prevalence of H pylori associated 'high risk gastritis' for development of gastric cancer in patients with normal endoscopic findings 总被引:1,自引:0,他引:1
Andreas Leodolter Matthias P Ebert Ulrich Peitz Kathlen Wolle Stefan Kahl Peter Malfertheiner 《World journal of gastroenterology : WJG》2006,(34)
INTRODUCTION H pylori infection is an established risk factor for development of gastric cancer[1,2]. According to the model of carcinogenesis of the intestinal type adenocarcinoma proposed by Correa, the multi-step development starts from the condition o… 相似文献
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Decreased caloric intake in normal-weight patients with bulimia: comparison with female volunteers 总被引:1,自引:0,他引:1
H E Gwirtsman W H Kaye E Obarzanek D T George D C Jimerson M H Ebert 《The American journal of clinical nutrition》1989,49(1):86-92
Patients with bulimia (binge-purge syndrome) frequently complain that they consume a very restrictive diet to avoid gaining weight. To investigate this claim, 23 hospitalized bulimic patients were assessed daily for body weight, caloric intake, macronutrient diet content, activity measures, and body composition estimates during weight-stable periods. Bulimic patients ate fewer kilocalories per kilogram body weight (22.1 +/- 4.6 kcal/kg) than did age-matched normal women (29.7 +/- 6.5 kcal/kg) but had similar activity levels and body composition. Clinical variables, such as history of laxative abuse, anorexia, or obesity, and physiological characteristics, such as body weight, activity level, or dietary content, could not account for this difference in caloric consumption. Bulimic patients tended to eat a diet lower in fat and higher in protein than did control subjects. These results agree with observations of increased efficiency of caloric utilization in obese patients and support patient complaints of a tendency to gain weight easily. 相似文献
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D Y Jones K W Miller B P Koonsvitsky M L Ebert P Y Lin M B Jones H F DeLuca 《The American journal of clinical nutrition》1991,53(5):1281-1287
The effect of olestra on vitamin D status was assessed in a 6-wk, double-blind, placebo-controlled study involving 202 free-living adults. Subjects consumed a total of 20 g/d of olestra or triglycerides in cookies eaten at each meal. A 20-micrograms ergocalciferol capsule was taken with each morning meal. Serum 25-hydroxyergocalciferol (25-OHD2) concentrations rose from approximately 5.7 to 39.0 and 31.7 nmol/L in the placebo and olestra groups, respectively, at week 6. At week 6, 25-OHD2 contributed 46-54% to total serum 25-OHD concentration compared with 11% at baseline. The 19% decrease in serum 25-OHD2 concentrations produced by olestra in this study is equivalent to a decrease of approximately 1.2 nmol/L under nonsupplemented dietary conditions. Ingesting 20 g olestra/d in the diet is thus not expected to affect vitamin D nutritional status. 相似文献
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Allografts of CNS tissue possess a blood-brain barrier. II. Angiogenesis in solid tissue and cell suspension grafts 总被引:2,自引:0,他引:2
R D Broadwell H M Charlton P S Ebert W F Hickey Y Shirazi J Villegas A L Wolf 《Experimental neurology》1991,112(1):1-28
Angiogenesis and patency of blood vessels were analyzed qualitatively in solid CNS and peripheral tissue syngeneic, allogeneic, and xenogeneic grafts and in individual cell suspension grafts of astrocytes, fibroblasts, PC12, and three additional tumor cell lines placed intracerebrally in adult host mice. Postgrafting survival times were 1 day through 4 weeks. The patency of graft vessels was determined in sections from immersion-fixed tissues incubated to reveal the endogenous peroxidase activity of host red cells trapped within the lumen of blood vessels. Additionally, horseradish peroxidase (HRP) was administered intravenously to live hosts; HRP labels host brain and graft vessels on the luminal surface and reveals the presence or absence of a blood-brain barrier (BBB) within the grafts. The origins of blood vessels supplying solid tissue xenografts were identified immunohistochemically with primary antibodies against host (athymic AKR mice) and donor (fetal Lewis rats) major histocompatibility complex (MHC) class I. Blood vessels supplying solid CNS grafts at 1-7 days post-transplantation were identified ultrastructurally and possessed interendothelial tight junctional complexes; however, they were not perfused with either host blood or blood-borne HRP prior to 8 days. Graft vessels at 10 days were outlined consistently by peroxidase-positive red cells in immersion-fixed material and labeled with blood-borne HRP. These vessels provided a BBB to the circulating HRP and exhibited interendothelial tight junctions. Evidence of angiogenesis within solid anterior pituitary grafts and the variety of cell suspension grafts was obtained prior to 3 days post-transplantation in immersion-fixed preparations; the vessels, with the notable exception of those supplying astrocyte cell suspensions, failed to present a BBB to blood-borne peroxidase. Endothelia in the solid pituitary allografts and the PC12 cell grafts were highly fenestrated and exhibited open interendothelial junctions; those in the tumor and fibroblast cell grafts, for the most part, appeared nonfenestrated, and many possessed open interendothelial junctional complexes. Immunostaining for host and donor MHC class I revealed that donor blood vessels predominate over host vessels in CNS xenografts and supply pituitary xenografts exclusively; in both preparations, donor vessels were not identified within the host CNS. Because cell suspension grafts were derived from endothelia-free preparations grown in culture, blood vessels supplying these grafts were necessarily of host CNS origin and manifested a morphological transformation from a BBB to a non-BBB endothelium. The data suggest that angiogenesis in solid CNS grafts placed into the adult host CNS, compared to similarly placed solid peripheral tissue/cell suspension grafts, is not rapid.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Clare E Herbert Martin A Ebert D Barclay David S Whittall David J Joseph Chris S Harper Nigel A Spry 《Medical Dosimetry》2003,28(1):27-30
A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate. 相似文献
9.
Oxygen-regulated control elements in the phosphoglycerate kinase 1 and lactate dehydrogenase A genes: similarities with the erythropoietin 3'' enhancer. 总被引:18,自引:5,他引:13 下载免费PDF全文
10.
This paper reviews the results of toxicity studies conducted in laboratory animals to evaluate the safety of the herbicide trifluralin (TFL). The data show that TFL is slightly toxic following single oral exposure. Testing for embryotoxicity in rats and rabbits indicated no teratogenic potential, and many different mutagenicity tests showed that TFL was non-genotoxic. Subchronic and chronic toxicity testing in rats, mice and dogs indicated that TFL was haematotoxic (anaemia and methaemoglobinaemia), particularly in the dog, and slightly hepatotoxic. No-observed-effect levels of 4.8 and 41 mg/kg body weight/day, respectively, were determined in dogs and rats exposed chronically to TFL. Oncogenicity studies in rats and mice revealed no carcinogenic potential. Since the data for TFL indicated no mutagenic or other special toxicological risks, it is suggested that a safety factor of 100 could be used for the determination of the acceptable daily intake of TFL, which would be 0.05 mg/kg body weight/day. 相似文献