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排序方式: 共有278条查询结果,搜索用时 15 毫秒
1.
2.
Psychological Consequences of Food Restriction 总被引:1,自引:0,他引:1
JANET POLIVY PhD 《Journal of the American Dietetic Association》1996,96(6):589-592
A review of the literature and research on food restriction indicates that inhibiting food intake has consequences that may not have been anticipated by those attempting such restriction. Starvation and self-imposed dieting appear to result in eating binges once food is available and in psychological manifestations such as preoccupation with food and eating, increased emotional responsiveness and dysphoria, and distractibility. Caution is thus advisable in counseling clients to restrict their eating and diet to lose weight, as the negative sequelae may outweigh the benefits of restraining one's eating. Instead, healthful, balanced eating without specific food restrictions should be recommended as a long-term strategy to avoid the perils of restrictive dieting. J Am Diet Assoc. 1996; 96:589-592. 相似文献
3.
A Dose-Response Analysis of Methoxychlor-Induced Alterations of Reproductive Development and Function in the Rat 总被引:14,自引:8,他引:6
GRAY L. EARL JR; OSTBY JOSEPH; FERRELL JANET; REHNBERG GEORGIA; LINDER RALPH; COOPER RALPH; GOLDMAN JEROME; SLOTT VALERIE; LASKEY JOHN 《Toxicological sciences》1989,12(1):92-108
A Dose-Response Analysis of Methoxychlor-Induced Alterationsof Reproductive Development and Function in the Rat. GRAY, L.E., JR., OSTBY, J., FERRELL, J., REHNBERG, G., LINDER, R., COOPER,R., GOLDMAN, J., SLOTT, V., AND LASKEY, J. (1989). Fundam. Appl.Toxicol12, 92108. In the present study rats were dosed fromweaning, through puberty and gestation, to Day 15 of lactationwith methoxychlor at 25, 50, 100, or 200 mg/kg/day. Morphologicallandmarks of puberty were measured, including the ages at vaginalopening, first estrus, and first estrous cycle in females andat preputial separation in males. In the female, estrous cyclicity,fertility, litter size, number of implantation sites, organweights, and ovarian and uterine histology were also measured.The viability of the offspring (F1) and their fertility wereevaluated using a continuous breeding protocol. Males were necropsiedafter breeding, the reproductive organs were weighed, and thecauda epididymal sperm counts were determined. One testis wasused for histopathology, while the other was used to quantifyinterstitial fluid (IF) content, IF testosterone concentration,and testicular sperm production. Testosterone and an drogen-bindingprotein were measured in the caput epididymis, and sperm motilityand morphology were evaluated from a caudal sample. The serumand pituitary were saved for hormonal determinations. Methoxychloraccelerated the age at vaginal opening and first estrus, andthe vaginal smears were cornified. Growth was retarded at 100and 200 mg/kg/day and fertility was reduced when the femaleswere bred with untreated or similarly treated males. In thehighest- dose group, the mated females went from constant estrusinto pseudopregnancy following mating, but they had no implants.In males, methoxychlor treatment markedly reduced growth, seminalvesicle weight, cauda epididymal weight, caudal sperm content,and pituitary weight. Puberty was delayed in the two highest-dosagegroups. Testicular sperm measures were much less affected thancaudal measures. Testis weight and histology were slightly affected,and testicular sperm production, sperm morphology, and motilitywere unaffected. Endocrine function of the testes and pituitarywas altered by methoxychlor administration. Leydig cell testosteroneproduction, in response to human chorionic gonadotropin challenge,was reduced and pituitary levels of prolactin, thyroid-stimulatinghormone (TSH), and follicle-stimulating hormone (FSH) were altered.In contrast, serum levels of prolactin, FSH, and luteinizinghormone were unaffected. Serum TSH was reduced by 50% of controlat 100 and 200 mg/kg/day, while pituitary levels were increased.Gonadotropin-releasing hormone concentration in the mediobasalhypothalamus was also elevated. In spite of the many reproductivealterations, the fertility of treated males was not reducedwhen they were mated with untreated females. Growth and viabilityof the offspring (F1) from the 50 mg/kg/day treatment groupwere normal, but in the females, vaginal opening was accelerated,estrous cyclicity was abnormal in the rats during middle age,and fecundity was reduced. 相似文献
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JANET E. PRITCHARD MSc APD MDAA CARYL A. NOWSON PhD MDAA JOHN D. WARK MBBS PhD FRACP 《Journal of the American Dietetic Association》1997,97(1):37-42
Objective To compare changes in total and regional body composition using dual energy X-ray absorptiometry (DEXA) after subjects lost weight through change in diet or exercise.Design A 12-month, randomized, controlled study of two weight-loss interventions — low-fat diet ad libitum or moderate, unsupervised exercise — in free-living, middle-aged men. Compliance was determined at monthly measurement sessions through food records and activity logs; DEXA scans were performed every 3 months.Subjects/setting Fifty-eight overweight men (mean body mass INDEX=29.0±2.6; mean AGE=43.4±5.7 years) recruited from a national corporation were assigned randomly to diet, exercise, or control groups.Interventions One group reduced dietary fat to 26.4% of energy intake but kept activity unchanged; another group self-selected aerobic exercise (three sessions per week at 65% to 75% maximum heart rate) but kept diet unchanged. A control group maintained weight.Main outcome measures At 12 months, measurements of weight, total and regional fat mass and lean mass, energy intake, and percentage dietary fat; physical activity indexes. Statistical analyses Results were analyzed using paired t tests and analysis of variance.Results Mean weight loss was 6.4±3.3 kg in dieters and 2.6+3.0 kg in exercisers; control subjects maintained weight. DEXA scans revealed that 40% of dieters’ weight loss was lean tissue; more than 80% of weight lost by exercisers was fat. Exercisers maintained limb lean tissue and lost fat mass.Conclusions Greater total weight and lean tissue loss occurred when subjects lost weight through a low-fat diet consumed ad libitum than when subjects participated in unsupervised aerobic exercise. Use of DEXA enabled identification of progressive total and regional changes in fat and lean tissue. J Am Diet Assoc. 1997; 97:37–42. 相似文献
6.
W. E. KARNES R. G. BERLIN V. MAXWELL BOYZENA SYTNIK JANET K. ROOT J. H. WALSH 《Alimentary pharmacology & therapeutics》1990,4(5):443-456
Hypergastrinaemia induced by potent inhibitors of acid secretion is thought to occur as a result of the elimination of the inhibitory effects of intragastric acid on gastrin release. The present study was designed to determine if the mechanisms responsible for feedback inhibition of gastrin release and acid secretion by intragastric acid are preserved during four weeks of varying degrees of drug-induced acid inhibition. Forty-eight healthy male volunteers were randomly assigned to one of four treatments for four weeks: 10 mg omeprazole o.m., 20 mg omeprazole o.m., 40 mg omeprazole o.m. or 150 mg ranitidine b.d. Gastrin release and acid secretion in response to peptone meals maintained at pH 2.5 and pH 5.5 by intragastric titration, and 24-hour gastrin profiles in response to standard meals were determined before treatment, at the fourth week of treatment and two weeks after discontinuing treatment. As expected, omeprazole produced dose-related effects on acid secretion and gastrin concentrations that were largely reversed after treatment was discontinued. Gastrin release in response to pH 5.5 peptone meals remained significantly greater than gastrin release in response to pH 2.5 meals during treatment with all doses of omeprazole. The ratio of pH 5.5/pH 2.5 peptone meal-stimulated gastrin release was approximately 1.5, and remained constant for all treatment groups throughout the study period. These data indicate that four weeks of drug induced hypochlorhydria causes an apparent increase in overall G-cell function, but it does not interfere with normal feedback inhibition of gastrin release and acid secretion mediated by intragastric acidity. 相似文献
7.
KAREN ROETMAN MD LEILA WELBORN MD RAAFAT HANNALLAH MD ROBERT FINK MD JANET NORDEN MSN & REGINA O'DONNELL BA 《Paediatric anaesthesia》1997,7(5):391-397
This study compared recovery characteristics and postoperative ventilatory function when halothane, fentanyl or combination of halothane and fentanyl in addition to N2O were used for intraoperative anaesthesia in term infants undergoing hernia repair as outpatients. Sixty-six full term ASA PS I infants ages 1–12 months were studied. All received inhalation induction with N2O, O2 and halothane, followed by intravenous atropine and atracurium, tracheal intubation, and controlled ventilation. For anaesthesia maintenance, patients were randomized into one of three groups. Group I received 70% N2O, 30% O2 and halothane. Group II received 70% N2O, 30% O2, halothane and 2 μg·kg?1 fentanyl. Group III received 70% N2O, 30% O2 and 10 μg·kg?1 fentanyl. Awakening times were similar in all three groups, however, Group I patients had significantly shorter recovery and discharge times than those of Group II and III. None of the patients experienced postoperative apnoea or periodic breathing. One patient in Group III experienced two brief episodes of bradycardia not associated with apnoea or arterial desaturation (Spo 2 >90% for greater than 30 s). Decreased Spo 2 occurred less frequently in Group I (5.9%) compared to Group II (22.7%) and Group III (19.0%) patients, however, the group differences were not significant. Transcutaneous CO2 (TcCO2) values were not statistically different among the three groups. Pain scores were initially lower in Groups II and III, but at 120 min the differences were not significant. Postoperative apnoea was not observed in this study. Spo 2 <90% and TcCO2 >9 kPa (70 mmHg) was more common in infants receiving 2 and 10 μg·kg?1 fentanyl than in infants receiving halothane and nitrous oxide anaesthesia. Infants <3 months old did not have a higher incidence of Spo 2 <90% or significantly higher TcCO2 values when compared to infants >3 months old. Fentanyl in doses used in this study did not prolong awakening time but did prolong recovery and discharge times in outpatient infants. 相似文献
8.
PAULA P. MEIER RN DNSc FAAN JANET L. ENGSTROM RN Ph D HENRY H. MANGURTEN MD ELIZABETH ESTRADA RN MS BETH ZIMMERMAN RN MS RAM KOPPARTHI MD 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1993,22(4):338-348
Objective: To describe a model for providing breastfeeding support in the neonatal intensive-care unit (NICU).
Design: Naturalistic, participant observation.
Setting: Suburban Level III NICU.
Patients: One hundred thirty-two mother-infant pairs over 1 year. Infants were hospitalized In the NICU, and mothers had initiated lactation efforts.
Interventions: Investigators provided breastfeeding interventions for the mother-infant pairs, based on identified problems, the research literature, or both.
Main Outcome Measures: Percentage of mothers who were breastfeeding at the time of discharge from the NICU.
Results: Interventions were classified into jive categories: expression and collection of mothers' milk, gavage feeding of expressed mothers' milk, in-hospital breastfeeding sessions, postdischarge breastfeeding management, and additional consultation.
Conclusions: This model was effective In preventing breastfeeding failure for this population. The model can provide the basis for NICU breastfeeding standards of care, protocols, and chart records, or for reimbursement purposes. The model also provides a framework for studying a specific category or breastfeeding intervention. 相似文献
Design: Naturalistic, participant observation.
Setting: Suburban Level III NICU.
Patients: One hundred thirty-two mother-infant pairs over 1 year. Infants were hospitalized In the NICU, and mothers had initiated lactation efforts.
Interventions: Investigators provided breastfeeding interventions for the mother-infant pairs, based on identified problems, the research literature, or both.
Main Outcome Measures: Percentage of mothers who were breastfeeding at the time of discharge from the NICU.
Results: Interventions were classified into jive categories: expression and collection of mothers' milk, gavage feeding of expressed mothers' milk, in-hospital breastfeeding sessions, postdischarge breastfeeding management, and additional consultation.
Conclusions: This model was effective In preventing breastfeeding failure for this population. The model can provide the basis for NICU breastfeeding standards of care, protocols, and chart records, or for reimbursement purposes. The model also provides a framework for studying a specific category or breastfeeding intervention. 相似文献
9.
Discrepancies Between Perceived Dietary Changes and 4-Day Food Records in Older Adults with Diabetes
10.
Visual spatial attention to stimuli presented on the vertical and horizontal meridian: An ERP study 总被引:6,自引:0,他引:6
THOMAS C. GUNTER ALBERTUS A. WIJERS JANET L. JACKSON GIJSBERTUS MULDER 《Psychophysiology》1994,31(2):140-153
In the first experiment, 48 subjects carried out a visual spatial attention task. Stimuli were presented at the vertical meridian, either above or below a fixation dot, and the subjects were instructed to attend to one of these stimulus positions and ignore the other position. In three different conditions, the distances between stimulus positions and fixation were 0.5°, 0.9°, and 1.3°. Subjects searched for the presence of prememorized target letters at the attended location: memory load was one or four items in different conditions. The P1/N1 enhancement typically found on the horizontal dimension was not observed on the vertical dimension. Instead, a positive shift of the attended compared with the unattended stimuli was found, which was most prominent at anterior electrodes. This positivity showed effects of the distance manipulation. The N2b-P3a effect of attention and the effect of memory load (search negativity) normally present in this kind of selective search task were also found. Reaction times were faster when attention was directed above fixation than when it was directed below fixation. The event-related potential data suggested that this difference could be attributed to a more efficient neglecting of irrelevant stimuli presented below fixation. In Experiment 2, we examined whether the absence of the P1/N1 enhancement as the result of spatial attention in Experiment 1 could be attributed to (a) the presentation of stimuli along the vertical meridian instead of along the horizontal meridian, (b) the use of midline electrodes instead of lateralized electrodes, and (c) the relatively small spatial separation between the relevant and irrelevant stimuli. Twelve subjects searched for the presence of a single target letter at an attended position in three different conditions. In two of the conditions the letters were presented to the left or right of fixation. The distance between fixation and the stimulus positions was 1.3° in one of these conditions and 3° in the other condition. In the third condition, the stimuli were presented at 3° above or below fixation. In all three conditions effects similar to those in Experiment 1 were observed. In addition, in all three conditions an enhancement of the P1 and N1 components was found at two lateral occipitotemporal electrodes. 相似文献