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991.
992.
AE Baughcum KA Burklow CM Deeks SW Powers RC Whitaker 《Canadian Metallurgical Quarterly》1998,152(10):1010-1014
OBJECTIVE: To identify maternal beliefs and practices about child feeding that are associated with the development of childhood obesity. DESIGN: Four focus groups. One group of dietitians from the Supplemental Nutrition Program for Women, Infants, and Children (WIC) in the Northern Kentucky Health District and 3 groups of mothers with children enrolled in WIC. SETTING: The WIC program in the Northern Kentucky Health District. PARTICIPANTS: Fifteen WIC dietitians and 14 mothers (14 to 34 years of age) with young children (12 to 36 months of age) enrolled in WIC. RESULTS: The mothers in this study (1) believed that it was better to have a heavy infant because infant weight was the best marker of child health and successful parenting, (2) feared that their infants were not getting enough to eat, which led them to introduce rice cereal and other solid food to the diets before the recommended ages, and (3) used food to shape their children's behaviors (eg, to reward good behavior or to calm fussiness). The mothers acknowledged that some of their child-feeding practices went against the advice of their WIC nutritionists and physicians. Instead, the participants relied on their mothers as their main source of information about child feeding. CONCLUSIONS: Physicians and allied health professionals discussing childhood growth with mothers should avoid implying that infant weight is necessarily a measure of child health or parental competence. Parents who use food to satisfy their children's emotional needs or to promote good behavior in their children may promote obesity by interfering with their children's ability to regulate their own food intake. Interventions to alter child-feeding practices should include education of grandmothers. 相似文献
993.
Glutathione (GSH) is an abundant and ubiquitous low-molecular-weight thiol which has proposed roles in many cellular processes including protection against the deleterious effects of reactive oxygen species. Our experiments have addressed the role of GSH in protection against hydrogen peroxide in the yeast Saccharomyces cerevisiae, and have shown that GSH and catalase provide overlapping defense systems. GSH appears to be the primary antioxidant for protection against hydrogen peroxide since mutants lacking GSH (gsh1) or glutathione reductase (glr1) are sensitive, whereas, strains lacking catalase A (cta1) or catalase T (ctt1) are unaffected in resistance to this oxidant. Furthermore, following treatment with hydrogen peroxide, the levels of oxidized, protein-bound and extracellular GSH were all increased at the expense of intracellular GSH. However, there are two lines of evidence that indicate catalases are required in the absence of GSH; firstly, strains that lack both catalase A and T accumulate increased levels of oxidized glutathione following treatment with hydrogen peroxide; and secondly, deletion of catalase genes exacerbates the hydrogen peroxide sensitivity of glr1 and gsh1 mutants. 相似文献
994.
The BCMA gene is a new gene discovered by the molecular analysis of a t(4;16) translocation, characteristic of a human T cell lymphoma. It has no significant similarity with any known protein or motif, so that its function was unknown. This report describes the cloning of murine BCMA cDNA and its genomic counterpart. The mouse gene is organized into three exons, like the human gene, and lies in murine chromosome 16, in the 16B3 band, the counterpart of the human chromosome 16p13 band, where the human gene lies. Murine BCMA cDNA encodes a 185 amino acids protein (184 residues for the human), has a potential central transmembrane segment like the human protein and is 62% identical to it. The murine BCMA mRNA is found mainly in lymphoid tissues, as is human BCMA mRNA. Alignment of the murine and human BCMA protein sequences revealed a conserved motif of six cysteines in the N-terminal part, which strongly suggests that the BCMA protein belongs to the tumor necrosis factor receptor (TNFR) superfamily. Human BCMA is the first member of the TNFR family to be implicated in a chromosomal translocation. 相似文献
995.
HG Yntema BC Hamel AP Smits T van Roosmalen B van den Helm H Kremer HH Ropers DF Smeets H van Bokhoven 《Canadian Metallurgical Quarterly》1998,35(10):801-805
Feeding difficulty and malnutrition are common in disabled children. Intake may be reduced because of anorexia, chewing and swallowing difficulties, or vomiting. Feeding is often time consuming, unpleasant, and may result in aspiration. Malnutrition may result in impaired growth and neurodevelopment, and impaired cardiorespiratory, gastrointestinal, and immune functions. Multidisciplinary assessment is recommended and should include a feeding history, oral-motor examination, and nutritional assessment. The energy requirements of most disabled children are less than those for a normal child of the same age but may be increased by spasticity, athetosis, convulsions, and recurrent infections. Micronutrient deficiencies may occur even in children receiving nutritionally complete feeds if the volume is reduced because of low energy requirements. Oral intake may be improved by a change of posture, special seating, feeding equipment, oral desensitization, mashing or pureeing of lumpy food, thickening of liquids, use of calorie supplements, and treatment of reflux/esophagitis. Non-oral feeding should be considered when oral feeding is unsafe, not enjoyable, inadequate, or very time consuming. Long-term support requires a gastrostomy. This is less obtrusive than a nasogastric tube, less likely to become displaced, less traumatic, and is associated with improved quality of life, but is also associated with significant morbidity. If there is symptomatic reflux a fundoplication may be required, but this is associated with significant mortality and substantial morbidity. 相似文献
996.
We asked whether the likelihood for mice of the C57BL/6J strain to develop glucose intolerance when fed a high-fat diet is related to the increase in circulating levels of leptin or free fatty acids (FFA). We therefore administered a high-fat diet (58% fat) or a control diet (11% fat) for 1.5 years. NMRI mice were used as a more glucose-tolerant control group. After a high-fat diet, the area under the glucose curve following an intraperitoneal glucose challenge (1 g/kg) increased more markedly in C57BL/6J mice (by 42+/-8%) than in NMRI mice (by 21+/-3%, P = 0.007). Plasma levels of insulin, leptin and FFA increased in both strains of mice, whereas plasma glucose levels were elevated after the high-fat diet only in C57BL/6J mice. The slope of the relationship between body weight and plasma leptin was higher in C57BL/6J mice than in NMRI mice. suggesting leptin insensitivity. Circulating leptin correlated to circulating insulin in both strains of mice, whereas plasma FFA correlated to plasma insulin in NMRI mice but not in C57BL/6J mice. These correlations remained significant after adjustment for body weight. The results show that elevated leptin and FFA levels evolve after high-fat feeding in mice, in conjunction with evolvement of glucose intolerance and hyperglycemia. 相似文献
997.
The effect of iron deprivation on the expression of outer membrane proteins and the ability to use heme as an iron source by uropathogenic Proteus mirabilis, Pr 6515, was studied. Examination of iron-restricted bacteria showed three outer membrane proteins ranging from 66 to 75 kDa to be affected by iron restriction, as well as a newly expressed 64-kDa protein. These proteins were induced within 15 minutes of iron-deprivation. The strain grew in the presence of ferric citrate, hemin and hemoglobin as iron sources, but could not use transferrin, lactoferrin or siderophores from exogenous sources. The 64- and 66-kDa proteins showed hemin-binding activity by affinity chromatography, and both reacted in Western blots with sera from mice transurethrally infected with the same strain. We suggest that P. mirabilis expresses iron-regulated outer membrane proteins that could be involved in heme uptake and may have a role in pathogenesis. 相似文献
998.
CP Cannon CM Gibson CH McCabe AA Adgey MJ Schweiger RF Sequeira G Grollier RP Giugliano M Frey HS Mueller RM Steingart WD Weaver F Van de Werf E Braunwald 《Canadian Metallurgical Quarterly》1998,98(25):2805-2814
BACKGROUND: Bolus thrombolytic therapy is a simplified means of administering thrombolysis that facilitates rapid time to treatment. TNK-tissue plasminogen activator (TNK-tPA) is a highly fibrin-specific single-bolus thrombolytic agent. METHODS AND RESULTS: In TIMI 10B, 886 patients with acute ST-elevation myocardial infarction presenting within 12 hours were randomized to receive either a single bolus of 30 or 50 mg TNK-tPA or front-loaded tPA and underwent immediate coronary angiography. The 50-mg dose was discontinued early because of increased intracranial hemorrhage and was replaced by a 40-mg dose, and heparin doses were decreased. TNK-tPA 40 mg and tPA produced similar rates of TIMI grade 3 flow at 90 minutes (62.8% versus 62.7%, respectively, P=NS); the rate for the 30-mg dose was significantly lower (54.3%, P=0.035) and was 65. 8% for the 50-mg dose (P=NS). A prespecified analysis of weight-based TNK-tPA dosing using median TIMI frame count demonstrated a dose response (P=0.001). Similar dose responses were observed for serious bleeding and intracranial hemorrhage, but significantly lower rates were observed for both TNK-tPA and tPA after the heparin doses were lowered and titration of the heparin was started at 6 hours. CONCLUSIONS: TNK-tPA, given as a single 40-mg bolus, achieved rates of TIMI grade 3 flow similar to those of the 90-minute bolus and infusion of tPA. Weight-adjusting TNK-tPA appears to be important in achieving optimal reperfusion; reduced heparin dosing appears to improve safety for both agents. Together with the safety results from the parallel Assessment of the Safety of a New Thrombolytic: TNK-tPA (ASSENT I) trial, an appropriate dose of this single-bolus thrombolytic agent has been identified for phase III testing. 相似文献
999.
KM Webber JN Pennefather GA Head M van den Buuse 《Canadian Metallurgical Quarterly》1998,86(4):1173-1180
The aim of the present study was to determine whether local administration of endothelin induces the release of dopamine in the rat striatum and to characterize and localize endothelin receptors in this brain region. Local injection of endothelin-1 (10 pmol) into the ventral striatum of urethane-anaesthetized rats caused an increase of 8 microM in the extracellular concentration of dopamine as measured by in vivo chronoamperometry. The peak increase in dopamine concentration occurred within 5 min of endothelin injection. Injection of the selective endothelin-B receptor agonist [Ala1.3,11.15]endothelin-1 (10 pmol) also caused an increase in extracellular dopamine concentration, suggesting that endothelin is acting at the endothelin-B receptor to elicit its effect. In rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal pathway, the response to local injection of endothelin-1 (10 pmol) was significantly inhibited on the lesioned side as compared to the non-lesioned side. In contrast, pretreatment of the rats with the N-methyl-D-aspartate receptor antagonist dizocilpine maleate (5 mg/kg, i.p.) or the nitric oxide synthase inhibitor NG-nitro-L-arginine (3 mg/kg, i.p.) did not alter the endothelin-induced release of dopamine. In binding studies, addition of endothelin-1 displaced [125I]endothelin-1 with a Ki of 220 pM. The endothelin-B receptor antagonist BQ788 displaced [125I]endothelin-1 with a Ki of 120 nM, whereas the endothelin-A receptor antagonist BQ123 produced only a 25% displacement at 10 microM, suggesting that endothelin receptors in the striatum are of the endothelin-B subtype. In rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal dopamine system, [125I]endothelin-1 binding was reduced by 53% in lesioned striatum compared to non-lesioned striatum, with no difference in the Kd. These data provide evidence that endothelin acts on a homogeneous population of endothelin-B receptors within the striatum to cause the release of dopamine and that a significant proportion of these receptors is located on dopaminergic neurons. 相似文献
1000.
BACKGROUND: This study has two goals: 1) to establish a generalizable model of the symptoms observed in outpatients with major depressive disorder (MDD); and 2) to compare symptom coverage of the Inventory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self-Report (IDS-SR) to that of the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI). METHODS: A factor analysis of IDS-C, IDS-SR, HDRS, and BDI items was carried out on 324 adult outpatients with MDD. Patients with coexisting Axis I or III illness or those taking psychotropic medication were excluded. RESULTS: Ten primary factors were identified, six of which were substantially intercorrelated, defining a second-order factor of general depression severity. Schmid-Leiman orthogonalization identified the symptoms most associated with general severity. CONCLUSIONS: The IDS provided more complete factors coverage than did the HDRS or BDI and thus may be more useful in research on symptom profiles. 相似文献