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71.
Macronutrient intakes, 2h and 12h, following administration of a selective 5-HT3 agonist, quipazine, N methyl, dimaleate (QUIPAZINE; 2.5, 5.0 and 7.5 mg/kg, i.p.) at dark onset were examined in three groups of adult male and female Wistar rats fed different sources of the three macronutrients: Group 1 (casein, corn starch, safflower oil), Group 2 (egg protein, corn starch/sucrose, lard) and Group S (casein hydrolysate, maltose dextrin, butter). QUIPAZINE decreased total food intake only in female rats from Group 1 (2 h) at a dose of 7.5 mg/kg and Group 2 (2h and 12h) with doses of 2.5 and 7.5 mg/kg. Intakes from corn starch and corn starch/sucrose diet (12h) were reduced in male and female rats, respectively, with doses of 2.5 and 7.5 mg/kg of QUIPAZINE. In conclusion, when provided with different sources of the three macronutrients, quipazine injection reduces specifically carbohydrate ingestion from corn starch-containing diets in male and female rats. Thus, the nature of the macronutrient source is of major importance to assess the effect of a drug on nutrient-specific selection. 相似文献
72.
Kim Paquette Stephanie Markey Stephanie Roberge Mario Girard Emmanuel Bujold Suzanne Demers 《Journal d'obstetrique et gynecologie du Canada》2019,41(1):59-63
Background
Lower uterine segment (LUS) thickness in the third trimester of gestation is associated with the risk of uterine scar defect at delivery. It was suggested that first trimester residual myometrial thickness (RMT) could also predict uterine scar defect at delivery.Objective
This study sought to correlate the RMT measured at the site of uterine scar in the first trimester with the LUS thickness measured in the third trimester.Methods
This was a prospective cohort study of women with a singleton pregnancy and a single prior low-transverse CS. All participants underwent an evaluation of uterine scar by using transvaginal ultrasound at 11 to 13 weeks, including the presence of a scar defect and measurement of RMT; and a second evaluation at 35 to 38 weeks, combining both transvaginal and transabdominal ultrasound, for the measurement of LUS thickness. Spearman's correlation test was used to compare first and third trimester measurements.Results
A total of 166 eligible participants were recruited at mean GA of 12.7?±?0.5 weeks. We observed an absence of correlation between first trimester RMT and third trimester LUS thickness (correlation coefficient 0.10; P?=?0.20). First trimester RMTs below 2.0?mm and below 2.85?mm are poor predictors of third trimester LUS thickness below 2.0?mm (sensitivity, 8% and 23%; specificity, 98% and 87%; positive predictive value, 25% and 14%, respectively).Conclusion
There is a poor correlation between first trimester RMT and third trimester LUS thickness in women with a previous CS. First trimester RMT should not be used to inform women on their risk of uterine rupture or to guide clinical management. 相似文献73.
Age-related postural deficits elicit compensatory mechanisms such as ankle dorsiflexion in the elderly. To gain further insight into this problem, the ability to match an ankle angle during quiet stance was studied in 12 elderly and 12 young subjects. Following an initial single limb angular perturbation presented in the ±4° range, a subject had to return a tilt platform to level, as determined by the nonperturbed limb. Elderly subjects exhibited significant positive (0.9°) over-shoot of the level position, in contrast to young subjects who matched ankle angle with a mean error of −0.1°. The elderly group also exhibited an increase in positioning error for angular displacements in the range between −1 and +1°. The results document age-related postural changes in ankle positioning which might affect postural stability in older adults. 相似文献
74.
Differential CT diagnosis of extruded nucleus pulposus 总被引:1,自引:0,他引:1
75.
The effect of ascorbate on cell death was examined in Jurkat cells (human T-cell leukemia) by incubation with dehydroascorbate (DHA), which is rapidly taken up by cells and efficiently reduced to ascorbate. Apoptosis was evaluated by caspase-3 activity in cell extracts and flow cytometry of annexin V-labeled cells. In parallel, necrosis was estimated by the release of lactate dehydrogenase. Minor effects on cell death were observed when Jurkat cells were incubated with either DHA alone (100–1,000 M) or a single dose of 10 M H2O2. However, pre-incubation with DHA followed by exposure to H2O2 clearly stimulated both apoptosis and necrosis. In complete contrast, pre-incubation of cells with DHA significantly inhibited apoptosis, but did not affect necrosis, induced by the topoisomerase I inhibitor camptothecin. Our results indicate that intracellular ascorbate can modulate cell death in a manner which depends upon the nature of the apoptotic stimulus, which in turn has critical implications regarding the mechanism and potential application of ascorbate in cancer therapy.Abbreviations CPT 20-S-camptothecin lactone - DHA Dehydroascorbate - LDH Lactate dehydrogenase - Ac-DEVD-AMC Ac-Asp-Glu-Val-Asp-amino-4-methylcoumarin - PS Phosphatidylserine - GSH Glutathione - DTT Dithiothreitol 相似文献
76.
77.
At birth, premature infants of 25-29 weeks gestation, at high risk for development of neonatal respiratory distress syndrome (RDS), were given a single dose (90 mg) of calf lung surfactant extract (CLSE) by intratracheal instillation. The frequency and severity of RDS were assessed with use of a simple radiographic scoring system in which pulmonary parenchymal densities and the prominence of the air-bronchogram effect were used as indicators of widespread atelectasis. Radiographs were obtained in surfactant-treated and control infants within the first 90 minutes of life as part of an initial evaluation of their pulmonary status. Subsequent examinations were performed at less than 24 hours and less than 48 hours of age. Radiographic assessment of lung disease compared consistently with coordinated data on oxygen and mean airway pressure requirements of the infants. Both indicated a significantly decreased frequency and severity of RDS in the infants treated with surfactant. The results provide supporting evidence of the effectiveness of exogenous lung surfactant replacement in mitigating RDS in very premature infants. 相似文献
78.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
79.
80.