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171.
M Wingens BH van Bergen PS Hiemstra JF Meis IM van Vlijmen-Willems PL Zeeuwen J Mulder HA Kramps F van Ruissen J Schalkwijk 《Canadian Metallurgical Quarterly》1998,111(6):996-1002
The hypothesis that consumption of bifidobacteria by humans would increase colonic bifidobacteria and decrease breath hydrogen excretion was examined. A commercially available strain of bifidobacteria was tracked through the gastrointestinal tract. We determined that a 12-d feeding period of 10(10) cells of exogenous bifidobacteria daily was adequate to achieve a stable number of exogenous bifidobacteria in the colon. A 12-d washout period was chosen because the exogenous bifidobacteria could no longer be detected at that time. A double-blind crossover study used both male and female subjects. The order of treatment with skim milk alone or skim milk + bifidobacteria was randomized. Breath hydrogen excretion (micromol/L) and fecal counts of total bifidobacteria [log colony forming units (CFU)/g feces] were not significantly different between males and females and were not affected by consumption of exogenous bifidobacteria. Calculations based on the numbers of exogenous bifidobacteria consumed and the fecal numbers of exogenous bifidobacteria excreted suggested that numbers of the exogenous strain increased within the gastrointestinal tract. These data suggest that it is difficult to permanently alter total colonic bifidobacteria and affect physiologic function (net hydrogen in the colon as reflected by breath hydrogen) by feeding bifidobacteria, although the percentage of the total bifidobacteria represented by the exogenous strain can be affected. 相似文献
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173.
WW Piegorsch AC Lockhart GJ Carr BH Margolin T Brooks GR Douglas UM Liegibel T Suzuki V Thybaud JH van Delft NJ Gorelick 《Canadian Metallurgical Quarterly》1997,388(2-3):249-289
Experimental features of a positive selection transgenic mouse mutation assay based on a lambda lacZ transgene are considered in detail, with emphasis on results using germ cells as the target tissue. Sources of variability in the experimental protocol that can affect the statistical nature of the observations are examined, with the goal of identifying sources of excess variation in the observed mutant frequencies. The sources include plate-to-plate (within packages), package-to-package (within animals), and animal-to-animal variability. Data from five laboratories are evaluated in detail. Results suggest only scattered patterns of excess variability below the animal-to-animal level, but, generally, significant excess variability at the animal-to-animal level. Using source of variability analyses to guide the choice of statistical methods, control-vs-treatment comparisons are performed for assessing the male germ cell mutagenicity of ethylnitrosourea (ENU), isopropyl methanesulfonate (iPMS), and methyl methanesulfonate (MMS). Results on male germ cell mutagenesis of ethyl methanesulfonate (EMS) and methylnitrosourea (MNU) are also reported. 相似文献
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175.
The rat paw formalin test is a model of prolonged pain due to mild tissue injury. There is some evidence suggesting that morphine does not produce antinociception in the formalin test via the brain-stem and spinal cord circuitry normally associated with antinociception. Furthermore, morphine appears to require an intact forebrain in order to function as an analgesic for formalin pain. In the 2 experiments reported here, we investigated the possibility that the central nucleus of the amygdala (Ce) contributes to the production of morphine antinociception (MA) in the formalin test. Nociception in this test occurs in 2 phases, with the 1st phase occurring 0-5 min after formalin injection and the 2nd phase beginning 10-15 min after injection and continuing for approximately 1 h. In Exp. 1, bilateral neurotoxic lesions of the Ce, but not lesions of the adjacent basolateral nucleus (BL), reliably attenuated MA (7 mg/kg morphine sulfate) during the 2nd phase of the formalin test without affecting baseline nociception. These results were obtained regardless of whether the rating scale method or flinch-frequency method of nociceptive scoring was used. During the 1st phase, Ce lesions reliably attenuated MA as measured by the flinch-frequency method, but not as measured by the rating scale method. In Exp. 2, Ce lesions also reliably attenuated the antinociception produced by 12 mg/kg morphine sulfate during the 2nd phase of the formalin test. Antinociception appeared to be almost completely re-instated, however, if the dose of morphine was raised to 20 mg/kg. The results indicate that neurons originating from the Ce contribute to the production of MA during the 2nd phase, and possibly the 1st phase, of the formalin test, especially at relatively lower doses of morphine. This suggests that in addition to coordinating conditioned antinociceptive responses, the amygdala may be a component of endogenous antinociceptive circuitry. These and other issues are discussed with reference to the spino-ponto-amygdaloid nociceptive pathway, and the proposed role of the amygdala in the mediation of defense reactions. 相似文献
176.
BH Marcus TK King AE Albrecht AF Parisi DB Abrams 《Canadian Metallurgical Quarterly》1997,26(4):586-597
BACKGROUND: The Commit to Quit trial was designed to address the methodological problems of prior studies that have examined the contribution of exercise to smoking cessation. METHODS: This paper provides an overview of the study design and describes the sample of women who participated in this trial (N = 281). Interrelationships among eating, exercise, and smoking behavior are examined. RESULTS: Subjects randomized into the study compared with the sample of women who completed the initial assessment but were not randomized were more likely to be white, to have at least a high school education, and to smoke fewer cigarettes per day. Overall, the most frequent ineligibility criteria were health-related issues and scheduling conflicts. On average, participants in this study smoked more cigarettes per day than national samples of women smokers. Significant interrelationships include the positive association of motivational readiness for quitting smoking and enhanced levels of dietary restraint and the positive association of motivational readiness for exercise adoption and high levels of weight concern. CONCLUSIONS: This study represents the first adequately powered randomized controlled clinical trial comparing the relative efficacy of a cognitive-behavioral smoking cessation treatment plus vigorous exercise with the same treatment plus contact control. 相似文献
177.
The BCL-6 proto-oncogene controls germinal-centre formation and Th2-type inflammation 总被引:1,自引:0,他引:1
BH Ye G Cattoretti Q Shen J Zhang N Hawe R de Waard C Leung M Nouri-Shirazi A Orazi RS Chaganti P Rothman AM Stall PP Pandolfi R Dalla-Favera 《Canadian Metallurgical Quarterly》1997,16(2):161-170
The incidence of nosocomial enterococcal infection has increased steadily over the past two decades. The treatment of patients with enterococcal infection has been complicated by the emergence of strains possessing high level resistance to aminoglycosides, penicillins and, most recently, glycopeptides. Several recent studies have evaluated alternative antimicrobial agents for use against strains resistant to some or all standard agents. In this report, we review the therapeutic options for the management of antibiotic-resistant enterococcal infection. 相似文献
178.
179.
BH Grayson S McCormick PE Santiago JG McCarthy 《Canadian Metallurgical Quarterly》1997,8(6):473-80; discussion 481-2
The role of preoperative planning, the geometric changes, and the long-term effects of mandibular distraction have not been previously reported. This study included 10 patients who underwent unilateral (5 patients) or bilateral (5 patients) mandibular distraction. Preoperative, postdistraction, and yearly radiographs (panoramic, posteroanterior, and lateral cephalograms) were reviewed. Postdistraction follow-up ranged from 12 to 70 months. Postdistraction, the mandibles showed evidence of anticipated growth without relapse. This growth rate was variable and dependent on the genetic program of the native bone. Previously reported improvement in temporomandibular joint morphology was maintained in the long term. The resulting shape of the neomandible was most influenced by the vector of placement of the distraction device. When placed vertically, ramal elongation was observed. When placed horizontally, anterior projection of the mandibular body occurred. When placed obliquely, ramal and body elongation occurred with preservation of the gonial angle. After 2 to 5 years of follow-up, continued growth of the neomandible was observed. 相似文献
180.
Oxidation of low density lipoprotein (LDL) has been recognized as playing an important role in the initiation and progression of atherosclerosis. In this study, the effects of aged garlic extract and one of its major compounds, S-allylcysteine, on oxidized LDL-induced cell injury were studied. Pulmonary artery endothelial cells were pre-incubated with the garlic extract (1, 2.5 and 5 mg mL-1) or S-allylcysteine (0.1, 1, 10 and 20 mM) at 37 degrees C and 5% CO2 for 24 h, washed, and then exposed to 0.1 mg mL-1 oxidized LDL for 24 h. Lactate dehydrogenase release as an index of membrane damage, methylthiazol tetrazolium assay for cell viability and thiobarbituric acid reactive substances indicating lipid peroxidation were determined. Preincubation of endothelial cells with the extract or S-allylcysteine significantly prevented membrane damage, loss of cell viability and lipid peroxidation. The data indicate that these compounds can protect vascular endothelial cells from injury caused by oxidized LDL, and suggest that they may be useful for prevention of atherosclerosis. 相似文献