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81.
OBJECTIVE: To test whether isoenergetic isoenergetically-dense doses of dietary 1-monoglyceride or triglyceride differentially influence appetite and meal-to-meal energy intake in man. DESIGN: Six men and six women were each studied twice in a 2 d protocol. On day 1 (maintenance day) they were fed a medium fat (MF) maintenance diet (MF: 40% fat, 47% carbohydrate and 13% protein by energy) calculated at 1.6 x resting metabolic rate (RMR). On day 2 (manipulation day) at 08.30 h subjects consumed a high-fat breakfast designed to contain 80-85% of RMR, composition 10% protein, 56% fat and 34% carbohydrate by energy, with 65% of energy for fat derived as either 1-monoglyceride or triglyceride. Food and energy intake were monitored at lunch (given at 12.30pm) and throughout the remainder of the day. During this time subjects had ad libitum access to isoenergetic, isoenergetically dense MF (40:47:13) foods (550kJ/100g), until 22.30pm). Subjective hunger and satiety were tracked hourly, during waking hours. RESULTS: There was no significant effect of fat type on food or energy intake at lunch or during the ad libitum period. There was no diet effect on subjective hunger (F(1,10)0.00; P= 0.975) in the inter-meal periods of morning or afternoon, nor during the whole day. Subjects found both diets to be similarly pleasant (F(1,61)0.84;P= 0.364). Men and women responded similarly, except that men ate more on all occasions than women. CONCLUSIONS: This study suggests that when a large dose of l-monoglyceride or triglyceride is incorporated into a breakfast meal, it behaves in a manner that is very similar to triglyceride in terms of the effects on hunger, appetite or feeding behaviour. 相似文献
82.
83.
JW Erdman AJ Thatcher NE Hofmann JD Lederman SS Block CM Lee S Mokady 《Canadian Metallurgical Quarterly》1998,128(11):2009-2013
The algae Dunaliella bardawil and Dunaliella salina naturally contain large concentrations of all-trans and 9-cis beta-carotene (betaC). The purpose of this study was to compare the relative serum and tissue accumulation of all-trans and 9-cis betaC in ferrets fed different ratios of all-trans/9-cis betaC derived from two commercial sources, D. bardawil or D. salina (Betatene). Male ferrets (7 wk old) were fed carotene-free, pelleted diets for 27 d. Beginning on d 18, groups of ferrets (n = 6 or 7) received daily, one of six oral supplements varying in ratios of 9-cis and all-trans betaC mixed with approximately 1.0mL of Ensure. Four supplements containing 5.2-8.3 micromol total betaC were prepared from a 20% Betatene preparation, D. bardawil, a high-cis Betatene preparation, and Betatene further enriched in 9-cis betaC with all-trans betaC/9-cis betaC ratios of 2.2, 1.5, 0.6 and 0.4, respectively. Two control supplements, high and low betaC, were prepared from commercial betaC beadlets. The high control supplement had an all-trans/9-cis ratio of 19.0, whereas 9-cis betaC was not detected in the low supplement. On d 27, serum and tissues were obtained for HPLC analysis of betaC and its isomers. Analysis of livers showed that all-trans betaC was the primary isomer present, but 9-cis and other isomers were also detected in all groups. The hepatic all-trans/9-cis ratios were 5.9, 4.9, 2.5, 1.4, 52.2 and47.5, respectively, for the groups listed above. Lower amounts of all-trans and 9-cis betaC were found in kidneys compared with the liver, but ratios of all-trans/9-cis were not different among groups. Only trace amounts of 9-cis betaC were found in serum. These results demonstrate that the algae D. bardawil and D. salina provide a bioavailable source of betaC isomers, but, as in humans, absorption of 9-cis betaC is poor and any 9-cis betaC absorbed is apparently cleared by the liver. 相似文献
84.
MR Kirshenbaum SF Chen CH Behrens LM Papp MM Stafford JH Sun DL Behrens JR Fredericks ST Polkus P Sipple 《Canadian Metallurgical Quarterly》1994,54(8):2199-2206
(R,R)-2,2'-[1,2-ethanediylbis[imino(1-methyl-2,1-ethanediyl)]]- bis[5-nitro-1H-benz[de]isoquinoline-1,3-(2H)-dione] dimethanesulfonate (DMP 840), is a bis-naphthalimide anticancer tumoricidal agent currently in phase I clinical trials. DMP 840 exhibits curative activity in human tumor xenografts, where it shows selectivity for human solid tumors over murine leukemias. In contrast to the selectivity found for DMP 840 in vivo, DMP 840 exhibits potent antiproliferative activity in vitro against a variety of human and murine leukemia and solid tumor cell lines in culture, with inhibitory doses that reduce the number of treated cells to one half (IC50) values ranging from 2.3 to 53 nM. DMP 840 was growth inhibitory to three doxorubicin-resistant cell lines with IC50 values also in the nanomolar range. Clonogenic survival experiments showed that DMP 840 was equally cytotoxic to both exponentially growing and quiescent human clone A colon carcinoma cells. A 1-h incubation of DMP 840 (1.22-12 microM) caused 5-log cell kill in KB-3-1 human epidermoid carcinoma, clone A human colon carcinoma, and L1210 murine leukemia cell lines. The rapid cell killing by DMP 840 in clonogenic survival experiments and initial mechanism of action studies was consistent with a DNA-interactive mechanism for DMP 840 cytotoxicity. Mechanism of action studies in L1210 leukemia cells demonstrated that DMP 840 inhibited the incorporation of thymidine and uridine into DNA and RNA with IC50 values of 0.55 and 0.08 microM, respectively. DMP 840 produced DNA single-strand breaks in a dose-dependent manner. Double-strand breaks were not observed with DMP 840 treatment, even at higher concentrations of compound. Chinese hamster ovary (CHO) and P388 cells resistant to camptothecin and containing a mutant form of topoisomerase I were also used to evaluate whether DMP 840 was cross-resistant with agents active against topoisomerase I. While the CHOR line was 163-fold resistant to camptothecin, the CHOR line was only 1.7-fold resistant to DMP 840. In summary, DMP 840 is a DNA-interactive agent that demonstrates excellent antiproliferative activity in vitro against cultured tumor cells from both human and murine sources. Its mechanism of tumoricidal activity may be novel. 相似文献
85.
The objective of this study was to address the question of whether or not psychosocial screening should be focused on "high-risk" populations. A cross-sectional survey of mothers of young children was conducted in various clinics: 758 in teaching clinics, 444 in private practices, and 202 at a military clinic. The self-administered questionnaire covered demographic factors, problems in mothers family of origin, maternal depression, and substance abuse. Mothers in the teaching clinics were younger and had less education and lower incomes than mothers in private practices, with intermediate levels in the military clinic. However, a substantial proportion of mothers seen in all sites reported psychosocial problems. Approximately 20% of mothers in all sites reported a family history of alcoholism. Positive screens for maternal depression ranged from about 15% to 35%. Binge drinking was reported by 10% to 20% at different sites. Psychosocial problems were common even among families seen in "low-risk" settings. Focusing screening only on high-risk clinics would miss many families with psychosocial problems. 相似文献
86.
Medico-demographic processes and socio-hygienic characteristics of the population of a large city, both at an individual and familial levels, as well as territorial characteristics of residence, should be taken into consideration when developing measures for medicosocial care of the population. Analysis of the attitude of 380 city families to the activities, personality, and professional skills of local therapists and pediatricians and to the idea of primary health care rendered by a physician of a general profile demonstrated an increased activity of the families in the "physician-patient" system and confirmed the necessity of improving medicosocial care of a city family, expansion of prophylactic work with the population with due consideration for factors which have an impact on population health. 相似文献
87.
Molecular computation of solutions to combinatorial problems 总被引:9,自引:0,他引:9
LM Adleman 《Canadian Metallurgical Quarterly》1994,266(5187):1021-1024
The tools of molecular biology were used to solve an instance of the directed Hamiltonian path problem. A small graph was encoded in molecules of DNA, and the "operations" of the computation were performed with standard protocols and enzymes. This experiment demonstrates the feasibility of carrying out computations at the molecular level. 相似文献
88.
LM Williams 《Canadian Metallurgical Quarterly》1995,8(4):649-673
This study provides evidence that some adults who claim to have recovered memories of sexual abuse recall actual events that occurred in childhood. One hundred twenty-nine women with documented histories of sexual victimization in childhood were interviewed and asked about abuse history. Seventeen years following the initial report of the abuse, 80 of the women recalled the victimization. One in 10 women (16% of those who recalled the abuse) reported that at some time in the past they had forgotten about the abuse. Those with a prior period of forgetting--the women with "recovered memories"--were younger at the time of abuse and were less likely to have received support from their mothers than the women who reported that they had always remembered their victimization. The women who had recovered memories and those who had always remembered had the same number of discrepancies when their accounts of the abuse were compared to the reports from the early 1970s. 相似文献
89.
BJ van Vlijmen NJ Pearce M Berg? B Staels JW Yates AD Gribble BC Bond MH Hofker LM Havekes PH Groot 《Canadian Metallurgical Quarterly》1998,48(4):396-402
PURPOSE: We report an investigation into the distribution of proteoglycans (PGs) in normal, organ-cultured and dextran-treated human corneas. METHODS: Immunogold labeling was carried out at the electron microscope level to localize keratan sulphate (KS), chondroitin sulphate (CS), and heparan sulphate (HS) PGs. RESULTS: High levels of labeling for CS was found in the epithelium, endothelium, and keratocytes, with light labelling present in the basement membranes and the corneal stroma. Labeling for HS was present in the epithelium, endothelium, and keratocytes, with intense labeling present at the endothelium/Descemet's membrane interface and the epithelium/Bowman's layer interface. Large filaments were also observed in these regions in cuprolinic blue-stained specimens. Keratan sulphate was present at high levels in the stroma and the basement membranes with low levels present within the keratocytes, epithelium, and endothelium. The pattern of KS labeling along the collagen fibrils in the stroma sometimes showed evidence of periodicity. Organ-cultured corneas had extensive collagen-free "lakes," the interior of which immunolabeled positively for KS and showed staining with cuprolinic blue. The lakes were greatly reduced in the dextran-treated samples. CONCLUSION: This investigation determined the ultrastructural distribution of KS, CS, and HS PGs in human cornea and showed that organ culture is associated with a change in distribution of stromal PGs. 相似文献
90.
JR McFarlane LM Foulds A Pisciotta DM Robertson DM de Kretser 《Canadian Metallurgical Quarterly》1996,134(4):481-489
BACKGROUND: The aim of this morphological investigation was to obtain more information about the structural and cellular mechanisms of interalveolar pore formation in postnatal lung development. Assuming that alveolar pore formation is related to the general thinning of interalveolar walls observed in the postnatal period, we have focused our attention on the topographical relationship between epithelial cells and connective tissue in the septum. Thereby we tried to formulate a uniform concept of pore formation. METHODS: After fixation with glutaraldehyde and osmiumtetroxide, tissue blocks of rat lungs aged 44 days were embedded in Epon. Serial sections were obtained in order to analyse precisely pores and supposed sites of pore formation (type II cells and thin spots in transsections of interalveolar walls). RESULTS: We made the following observations: there are pores with or without type II cells in the neighbourhood, and "pre-pores" with either fully transseptal granular pneumocytes, or thin spots in the interalveolar wall consisting of one or two layers of type I cell epithelium or of type II and type I cells without intervening connective tissue. CONCLUSIONS: From these findings we deduce that there is a general principle of interalveolar pore formation which consists in the formation of transseptal interepithelial cell contacts (i.e., between cells of type II and type I or type I and type I), promoted by the thinning of interalveolar walls in the stage of microvascular maturation. Within the zone of contact the cells thin out and give way to form an interalveolar opening. 相似文献