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BS Pedersen OH Hel? FB J?rgensen H Kromann-Andersen 《Canadian Metallurgical Quarterly》1998,160(50):7259-7262
Appital is a herbal medicine. The aim was to examine its effect in patients with irritable bowel syndrome (IBS). Other diseases were excluded by physical examination, rectoscopy, blood tests and in patients older than 35 years X-ray of the colon or colonoscopy. The study was designed as a double-blind placebo-controlled trial. The patients were randomized to either Appital or placebo. Following two weeks without medicine, the patient had Appital or placebo for eight weeks. Fifty-nine patients were randomized, 47 completed the study. The results were based on symptom scores registered by the patients. The symptom score was significantly reduced in patients treated with Appital (p = 0.002), but when compared to placebo, the difference was insignificant (p = 0.081). We concluded that Appital has no effect in relieving symptoms of IBS compared to placebo, although due to the possibility of type two error we cannot exclude a small, but hardly clinically relevant effect. 相似文献
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GM Pantalos F Altieri A Berson H Borovetz K Butler G Byrd AA Ciarkowski R Dunn OH Frazier B Griffith DW Hoeppner JS Jassawalla RH Kormos RT Kung B Lemperle JP Lewis DG Pennington VL Poirier PM Portner G Rosenberg R Shanker JT Watson 《Canadian Metallurgical Quarterly》1998,66(5):1852-1859
Jointly developed by members of the American Society for Artificial Internal Organs and the Society of Thoracic Surgeons along with staff from the Food and Drug Administration, the National Heart, Lung and Blood Institute and other experts, this recommendation describes the reliability considerations and goals for Investigational Device Exemption and Premarket Approval submissions for long-term, mechanical circulatory support systems. The recommendation includes a definition of system failure, a discussion of an appropriate reliability model, a suggested in vitro reliability test plan, reliability considerations for animal implantation tests, in vitro and animal in vivo performance goals, the qualification of design changes during the Investigational Device Exemption clinical trial, the development of a Failure Modes Effects and Criticality Analysis, and the reliability information for surgeons and patient candidates. The document will be periodically reviewed to assess its timeliness and appropriateness within five years. 相似文献
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The pathologic characteristics and clinical presentation of patients with primary hyperparathyroidism are discussed including the treatment of hypercalcemic crisis. Surgical issues, including the use of localizing studies, and the surgical treatment of primary hyperparathyroidism are reviewed. 相似文献
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Skin tumour development was studied in groups of mice painted once with 125 mug of 3-methylcholanthrene (MCA) either at 12:00 or at 24:00 MET. Eight animals were kept in each box. The animals were observed weekly for 20 months and all tumours were registered. There was no difference between the two groups of mice as regards tumour induction time or number of papilloma-bearing mice. In the groups of mice treated at 24:00 the number of skin tumours to develop was 9 per cent higher than in groups of mice treated at 12:00. This difference in papilloma yields is not statistically significant. Among female mice painted at 24:00 carcinoma-bearing animals were significantly more numerous (50 per cent) than among those painted at 12:00, whereas there was no difference between the groups of male mice. Considering the groups collectively (males + females), the intergroup difference (17 per cent) in advantage of painting at 24:00 was barely significant (0.5 less than p less than 0.10). There was no difference between the groups as regards the total number of carcinomas to occur. When the tumour yields in individual boxes were found to vary greatly. The slight increase in tumour yield after night painting correlates with the circadian variation in proliferative activity of the epidermidis. Previous reports in the literature have shown similar differences. Further investigations and better methods seem necessary before a definite conclusion can be drawn concerning a possible diurnal variation in the susceptibility of mouse skin to chemical carcinogenesis. It is also emphasized that it is necessary to exercise great caution when the results of classical epidermal chemical carcinogenesis experiments are to be interpreted. It seems necessary to observe animals for at least 15 months before any conclusion can be drawn. 相似文献
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OH Perez R Aznar LM Ballesteros JD Mendez A Rosado 《Canadian Metallurgical Quarterly》1976,14(4):421-433
Ribonucleic acid (RNA) metabolism of the normal and copper-treated ( Cu-T200 IUD) human endometrium was investigated. The relative concentration of total, messenger, ribosomal and transfer RNA was measured in normal and Cu-treated endometrium using the technique of affinity chromatography in polysepharose. The transition from the proli ferative to the secretory endometrium in normal women was accompanied by significant increases (p less than .05) in total RNA, messenger RNA and in ribosomal RNA. The relative proportions of bound and free messenger RNA were also modified by endometrial maturation changing from 70% bound messenger RNA in the proliferative to 83% in the secretory phase. Cu-T200 Cu release appeared to particularly affect RNA metabolism in the secretory phase. During the proliferative phase only the concentration of transfer RNA and the proportion of bound to free messenger RNA were modified by the Cu-T200. The Cu-T200 induced significant decreases (p less than .01 and p less than .05) in all RNA parameters, with the exception of the RNA/deoxyribonucleic acid ratio. 相似文献
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