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141.
142.
Diversity and specialization of mammalian SWI/SNF complexes 总被引:2,自引:0,他引:2
W Wang Y Xue S Zhou A Kuo BR Cairns GR Crabtree 《Canadian Metallurgical Quarterly》1996,10(17):2117-2130
143.
JD Skinner BR Carruth KS Houck F Coletta R Cotter D Ott M McLeod 《Canadian Metallurgical Quarterly》1997,97(5):496-504
OBJECTIVE: To determine the nutrient and food intakes of healthy, white infants from families of middle and upper socioeconomic status and to compare intakes to current recommendations. DESIGN: Using an incomplete random block design, we interviewed 98 mother-infant pairs longitudinally when infants were 2, 3, 4, 6, 8, 10, 12, 16, 20, and 24 months old. Data obtained included 24-hour dietary recalls, usual food intake, and food likes and dislikes. SETTING: Interviews were conducted in the mother's home by registered dietitians. Subjects resided in two urban areas of Tennessee. SUBJECTS: Of the original 98 subjects, 94 completed the 2-year study. RESULTS: Mean energy and nutrient intakes generally met or exceeded the Recommended Dietary Allowance (RDA). Exceptions were zinc and vitamin D, which were each below 100% of the RDA at 9 of the 10 data points, and vitamin E, which was below the RDA in the infants' second year. Fat intake decreased from more than 40% of energy in the first 6 months to 30% to 32% from 10 to 24 months. One third of the infants drank reduced-fat milks at 12 months and more than half drank them at 24 months. Although infants ate a variety of foods, vegetables often were the least favorite foods. A variety of dairy products provided calcium for the infant but lacked vitamin D. CONCLUSIONS: Several nutritional issues about infant feeding before 2 years of age arose. Low intakes of zinc, vitamin D, and vitamin E were observed. In the second year, low fat intake, use of reduced-fat milks, and dislike of vegetables were areas of concern. 相似文献
144.
The effects of phenytoin (DPH), carbamazepine (CBZ) and diazepam (DZP) on anoxia-induced injury in CNS white matter were studied using the in vitro rat optic nerve preparation. Optic nerves were subjected to 60 min of anoxia and functional recovery was assessed using the area under the compound action potential. Under normoxic conditions, application of DPH, CBZ and DZP reduced compound action potential area over concentration ranges known to block sodium channels. All three compounds, however, protected against anoxic injury at concentrations below those that inhibited the normoxic compound action potential. Thus, the application of 1 microM DPH, CBZ or DZP during anoxia resulted in compound action potential recovery to 60.0, 53.8 and 69.2% of control, respectively, compared to compound action potential recovery of 34.8% in the absence of drugs (P < .05 in all three cases). In the cases of CBZ and DPH, 60% improvement in recovery from anoxia was produced by concentrations well below those employed clinically to treat epilepsy, suggesting a potential role for these drugs in the protection of CNS white matter from anoxic injury. 相似文献
145.
146.
DJ Hentges BR Maier GC Burton MA Flynn RK Tsutakawa 《Canadian Metallurgical Quarterly》1977,37(2):568-571
Ten human volunteers completed a 4-month diet series consisting of 1 month each of a control diet, a meatless diet, a high-beef diet, and the same control diet. Fat and fiber contents were essentially the same in all four diets, but protein content was doubled during the high-beef diet. During the 4th week on each diet, three stool specimens collected from each volunteer were analyzed for chemical composition and content of facultative, aerobic, and anaerobic bacteria. The bacteriological data are presented in this paper. High beef protein consumption had little effect on the composition of the intestinal flora. There were no significant differences in total counts of facultative and aerobic or anaerobic organisms in the feces when volunteers were on meatless or high-beef diets. At the species level, when counts during the two control diets were comparable, in only three instances did the change from the meatless to a high-beef diet significantly influence the bacterial numbers. The ratio of mean counts of anaerobic to facultative and aerobic organisms was approximately 15:1 during the meatless diet and 34:1 during the high-meat diet. The data indicate that animal protein consumption has little effect on the fecal bacterial profile in humans. 相似文献
147.
148.
An experimental model of acute compartment syndrome involving the anterolateral compartment of the hindlimb in dogs was used to compare three methods of measurement of intracompartmental pressure: the simple-needle technique, use of the slit catheter, and use of the side-ported needle. No statistical difference was found between the values obtained with the slit catheter and those obtained with the side-ported needle; the mean difference was 1.4 millimeters of mercury throughout the range of compartment pressures that were measured. The side-ported needle appeared to be as accurate as the slit catheter for the measurement of compartment pressures (p = 0.355, 1-beta = 0.9). The values obtained with use of the simple needle were consistently higher than those obtained with the other two methods (p < 0.001): an average of 18.3 millimeters of mercury higher than the values measured with the slit catheter and 19.3 millimeters of mercury higher than those measured with the side-ported needle. Clinically, the side-ported needle or the slit catheter can be used to obtain accurate measurements of compartment pressure. Use of the simple 18-gauge needle is not recommended for this purpose. 相似文献
149.
BR Bhavnani 《Canadian Metallurgical Quarterly》1998,217(1):6-16
Raf-1, A-Raf and B-Raf comprise a small family of highly conserved serine/threonine protein kinases, whose activities play a fundamental role in the control of proliferation and differentiation. The best studied family member, Raf-1, is expressed ubiquitously and constitutively, and its activity is regulated by post-translational mechanisms. Raf-1 can be activated by many signals that include growth factors, tumor promoters, inflammatory cytokines, calcium mobilization, DNA damaging agents, and oxygen radicals. Ras-mediated translocation of Raf-1 to the plasma membrane is a crucial step in its activation process, and is thought to facilitate phosphorylation by membrane-bound kinases. Raf-1 has also been reported to undergo intracellular redistribution following its activation: to the perinuclear space in murine NIH3T3 cells and rat hepatic Ito cells, and into the nucleus in gerbil hippocampal pyramidal cells and human MO7 leukemia cells. In contrast to the translocation to the plasma membrane, the perinuclear and/or nuclear translocation of Raf-1 has not been investigated in detail. In this paper, we report an examination of the subcellular localization of endogenous Raf-1 in a fibroblastic cell line (Rat-1) commonly used in transformation assays. Using the methods of cellular fractionation as well as in situ immunofluorescence, we show that no detectable movement of Raf-1 to the perinuclear or nuclear space can be observed. Tethering of activated Raf to the plasma membrane does not interfere with its transforming activity. 相似文献
150.