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61.
The aim of the present study was to evaluate the relation between iron status and cancer in a population of middle-aged adults living in France where iron supplementation and iron-fortified foods are rarely used. The SU.VI.MAX study is a randomized, double-blind, placebo-controlled primary prevention trial evaluating the effect of antioxidant supplementation on chronic diseases in women aged 35-60 and men aged 45-60 y. At baseline, concentrations of hemoglobin, serum transferrin and serum ferritin were measured in 10,197 subjects. Data on dietary intake were estimated from six 24-h dietary records completed during the first 2 study years and available for 5287 subjects. All cancer cases that occurred during the 7.5-y follow-up were validated. In men, baseline serum transferrin and serum ferritin concentrations did not differ between subjects with cancers (n = 467) and those without. In women, serum ferritin was higher (P < 0.0001) and serum transferrin tended to be lower (P < 0.08) in cancer cases. Iron status was not related to cancer risk in men, but women with serum ferritin concentrations > 160 microg/L had an increased risk of cancer (odds ratio = 1.88, 95% CI: 1.05,3.35). No relation was found between dietary iron intake and risk of all cancer sites combined for either men or women. Our results suggest that iron status is not a predictor of cancer risk in men, whereas a serum ferritin concentration > 160 microg/L may be associated with an increase in cancer risk in women.  相似文献   
62.
BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability.  相似文献   
63.
PURPOSE: The permeability of 13 different gloves to 13 cytotoxic agents under controlled dynamic conditions is described. METHODS: Thirteen cytotoxic agents were prepared at the highest concentrations normally encountered by pharmacy personnel. Four glove types--neoprene, natural rubber latex, nitrile, and vinyl--were exposed to the cytotoxic agents for 15, 30, and 60 minutes. Tests were conducted using the middle finger of each glove. Linearity, reproducibility, and sensitivity were evaluated for each drug tested. Assays were run using liquid chromatographic tandem mass spectrometry (LC/MS/MS) and high-performance liquid chromatography with ultraviolet light (HPLC-UV). Permeability testing was conducted using an original system designed to evaluate dynamic constraints, such as rubbing, stretching, and tension. RESULTS: Linearity by LC/MS/MS and HPLC-UV was confirmed at concentrations up to 1000 ng/mL for all drugs. Most glove materials were permeable at rates below ASTM recommendations over the one-hour testing period. Vinyl was the most permeable material. Carmustine permeated the widest variety of materials. Due to the high sensitivity of the analytic methods, all materials displayed low but significant permeability for at least one drug after one hour. Higher resistance to permeation was recorded for all neoprene, some natural rubber latex, and one nitrile glove. CONCLUSION: Neoprene, natural rubber latex, and nitrile gloves displayed the highest resistance to permeation of the 13 cytotoxic agents studied. Additional factors, such as duration of exposure, glove thickness, and drug liposolubility and molecular weight, also affected permeability.  相似文献   
64.
It is well established that blood zinc concentrations fall postoperatively but documented data does not exist proving a direct relation between the fall in levels and the serious or otherwise nature of surgery performed. This relation was investigated in 25 patients, distributed into three groups as a function of severity of operation, by determining total serum zinc and also its distribution amongst vector proteins and amino acids. Findings indicated that minor procedures such as leg varicose vein stripping failed to affect blood zinc whereas major surgery (extracorporeal circulation) provoked a fall of 47% in blood zinc levels. In addition, this reduction affected only the exchangeable fraction (which is therefore the only one biologically active) of serum zinc. This suggests the need for zinc supplementation to assist healing and re-establish immunity phenomena after major surgery.  相似文献   
65.
Levine  MS; Gasparaitis  AE 《Radiology》1986,160(1):264-265
Severe glucagon-resistant spasm on double-contrast barium enema (DCE) examinations may occasionally lead to a nondiagnostic examination or erroneously suggest colonic disease. In such cases, this glucagon-resistant spasm may be overcome by refilling the colon with single-contrast barium immediately after completion of the DCE examination.  相似文献   
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Systemically administered 4-S-cysteaminylphenol (4-S-CAP) and N-acetyl-4-S-CAP inhibited the growth of xenografts of a human melanoma cell line but not of an ovarian tumour cell line. No selective cytotoxicity for melanoma cells was observed in culture, however. Further study of the in vitro mechanism of 4-S-CAP toxicity showed minimal inhibition of tyrosinase activity or DNA, RNA and protein synthesis, and there was no phase-specific arrest of the cell cycle. However, expression of an 80 kD melanosomal antigen was decreased. Cytotoxicity of 4-S-CAP in culture was decreased by simultaneous treatment with a monoamine oxidase inhibitor. An affinity column prepared from 4-S-CAP retained several proteins from a melanoma cell lysate. One protein, found also in HeLa cells, was identified by N-terminal sequencing as protein disulphide isomerase, a molecule which has multiple roles in the modification of secretory proteins. These results identify a protein target for 4-S-CAP as one possible mechanism of cytotoxicity.  相似文献   
70.
Effacement of the fetal cisterna magna in association with myelomeningocele   总被引:2,自引:0,他引:2  
Goldstein  RB; Podrasky  AE; Filly  RA; Callen  PW 《Radiology》1989,172(2):409-413
The cisterna magna is effaced in association with myelomeningocele. The authors retrospectively investigated the size of the fetal cisterna magna as a predictor of fetal myelomeningocele in 67 pregnant women (17-38 menstrual weeks) referred for prenatal sonography because of an elevated serum alpha-fetoprotein level (n = 61) or a suspicion of fetal ventriculomegaly on previously obtained sonograms (n = 6). Twenty fetuses had myelomeningocele, 14 had isolated ventriculomegaly, and 33 were normal. A normal-sized cisterna magna (range, 4-9 mm in depth) was present in all normal fetuses. In 19 of 20 fetuses with myelomeningocele, the views of the posterior fossa were adequate, and in each of these the cisterna magna was effaced (n = 18) or very small (n = 1). The cisterna magna was effaced in five of 13 (38%) fetuses with isolated ventriculomegaly in whom the posterior fossa was adequately imaged. Although effacement of the cisterna magna is a nonspecific finding, the high negative predictive value of this sign is useful during routine screening of the fetal neural axis.  相似文献   
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