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The effect of caseinate and soy protein in the diet on the mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was assessed in-vivo and ex-vivo in the DNA-repair host-mediated assay and liquid suspension assay, respectively. Of the two proteins only casein showed a strong antimutagenic activity over the whole digestive tract, except in the stomach. It is suggested that the molecular structure of a protein determines its protective effect against mutagens: casein lacks secondary and tertiary structure so that amino acids are more readily available for interaction with the mutagen than with the amino acids in soy protein which is a globular protein. 相似文献
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Lichen sclerosus is a chronic skin condition with a predilection for the genital area. In the present study, 35 male patients with lichen sclerosus were interviewed and examined. Blood screens were performed and histology was requested if not already performed. The findings indicate that lichen sclerosus in males exists as a spectrum of disease, ranging from a mild form with white plaques and few symptoms to a severe form with inflammation, atrophy and scarring with possible urological consequences. In many areas it differs from the condition in females; the association with autoimmune disease is weaker and there is less perianal and extragenital involvement. The association with malignancy in males is of lesser significance than initially believed. 相似文献
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An on-line, steam distillation/purge and trap gas chromatographic procedure is described for determination of halogenated analytes in foods and beverages. Recoveries were generally >80% (versus aqueous standards) from vegetable oil, flour, root beer, cream (10% butter fat), and milk spiked at 1-3 micrograms/kg for each of the 32 analytes studied. Analytes ranged in volatility from vinyl chloride to 1,2,3,4-tetrachlorobenzene. Repeatabilities from aqueous standards were <10% for most analytes. For a 1 g food sample, method detection limits ranged from 0.02 to 0.2 micrograms/kg for the 32 analytes. Reduced recoveries for less volatile analytes, however, occurred when steam-distillable, nonpolar food components were carried to the sparger. This effect was observed for citrus beverages containing steam-volatile limonene, roasted and ground coffees, and some salad dressings. The method was applied to a variety of foods. 相似文献
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The effectiveness of a combined regimen of mifepristone and vaginal misoprostol for termination of pregnancies of 9-13 weeks of gestation was investigated in 120 UK abortion patients (median age, 22.1 years; median duration of amenorrhea, 10.3 weeks). Each woman received a single oral dose of 200 mg of mifepristone 36-48 hours before admission, at which time 800 mcg of misoprostol was administered vaginally. Where indicated, a further two doses of 400 mcg of misoprostol (vaginal or oral) were provided every 3 hours. All 120 women aborted on the day of prostaglandin administration; however, 6 women (5%) required exploratory curettage after the procedure for retained placenta. The median prostaglandin dose was 1200 mcg (range, 800-1600 mcg). The median time from misoprostol administration to abortion was 4.33 hours (range, 1.3-16.0 hours). 60 women (50%) required oral analgesics and 26 (22%) received parenteral analgesia. Diarrhea occurred in 38 women (32%). The median duration of bleeding after abortion was 12.5 days (range, 3-43 days). In questionnaires administered to 73 women, only 3 (4%) expressed dissatisfaction with medical abortion, because of pain or prolonged bleeding. The relatively high dose of misoprostol used in this study and the vaginal route of administration are presumed to account for the 95% success rate. Extension of medical abortion to later gestation times would decrease the need for surgery and expand women's choice of methods of pregnancy termination. 相似文献
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A review of 35 patients > 60 years of age with odontoid fractures showed that a type II injury (Anderson and D'Alonso) was the most common fracture pattern (82% of cases). On the basis of mechanism of injury and sex incidence, we deduced that osteopenia is a contributory factor in the occurrence of odontoid fractures. A fall in a domestic setting was the cause in 53%. The peg was posteriorly displaced in 88% of type II fractures, and primary union occurred in 23%. The incidence of concomitant spinal cord injury with type II fractures was higher in older patients than it was in those < 60 years of age. The outcome for these patients was largely determined by their neurological status at presentation. Myelopathy as a late complication of nonunion was not observed in nine patients with an average follow-up of 21 months. The data suggest that vigorous attempts to secure both primary union and a sound arthrodesis for non-union are questionable in the elderly except in unusual circumstances. 相似文献