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91.
J Tonkiss JS Shumsky PL Shultz SS Almeida JR Galler 《Canadian Metallurgical Quarterly》1995,17(5):601-608
The separate and combined effects of prenatal cocaine exposure and malnutrition on mother-pup interactions in rats were assessed daily from postnatal day 2 to day 21. Sprague-Dawley dams were fed a diet of low protein content (6% casein), an isocaloric diet of adequate protein content (25% casein, control), or a laboratory chow diet prior to mating and throughout pregnancy. Within each diet group, rats received either cocaine injections (30 mg/kg IP two times per week prior to mating and then 30 mg/kg SC daily from days 3 to 18 of pregnancy) or saline injections. Litters were fostered on the day of birth to control mothers (i.e., nondrug-exposed dams fed the control or chow diet). Foster mothers fed the 25% casein diet showed increased contact with cocaine-exposed pups compared with nondrug-exposed pups in the second postnatal week but lower levels as the pups approached weaning. Passive nursing was increased in dams caring for prenatally malnourished, cocaine-exposed pups compared with those caring for similar pups with no drug exposure. Chow-fed mothers did not differ in their behavior towards pups with or without prenatal cocaine treatment. Prenatal cocaine and malnutrition independently compromised birth weight and various reflexive milestones but the attainment of physical milestones was affected only by prenatal cocaine. There were no additive effects of the two prenatal insults on any measure of mother-pup interaction or pup development. 相似文献
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PL Tecklenberg J Fitzgerald BI Allaire EL Alderman DC Harrison 《Canadian Metallurgical Quarterly》1976,38(7):956-958
The primary goal in the medical management of ventricular septal defect complicating myocardial infarction is to support cardiac function and control symptoms, if possible, for a period of 4 to 6 weeks. If the patient survives this period, surgical correction of the defect is technically easier and safer. In many cases, However, cardiac function is severly compromised, intractable biventricular failure develops,early operation is necessary and the likelihood of successful repair is diminished. 相似文献
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Thirty children seen between 1954 and 1970 with the diagnosis of anorexia nervosa were contacted between five and twenty years after initial treatment. Patients outcomes in terms of education, weight in adulthood, medical problems, marriage, psychiatric treatment, and recurrence of anorexia were surveyed. Results corroborate those of earlier studies suggesting that adjustment in adulthood is related to personality type. 相似文献
98.
D. N. Paulson R. L. Kleinberg J. C. Wheatley 《Journal of Low Temperature Physics》1976,23(5-6):725-741
The propagation of 5-, 15-, and 25-MHz sound in superfluid 3He has been studied in zero magnetic field over a wide pressure range. Measurements of the structure and location of the attenuation peaks, velocity changes, and the low-temperature attenuation are described. The degree of strong coupling in the B phase is discussed. Observations of superheating and supercooling near the polycritical point have been extended and comparison is made with theory.Work supported by the U.S. Energy Research and Development Administration under Contract No. E(04-3)-34, P.A. 143. 相似文献
99.
This paper is an extension of, and complementary to, an earlier paper by Wheatley, Vilches, and Abel. Some important fundamental questions which lead to degradation in the performance of a dilution refrigerator are considered: namely, convection on the dilute side and superfluid on the concentrated side. Experimental results are presented for a film suppressing still used in conjunction with a continuous-heat exchanger (several designs are considered) and a variable number (0–6) of step-heat exchangers of a copper-foil type with a high surface-area-to-viscous-impedance ratio. The first quantitative measurements of viscous heating on the dilute side are presented as well as measurements of thermal resistance on the dilute and concentrated side. Finally, the properties of the refrigerator under external heat load are considered.Supported by the U.S. Atomic Energy Commission under Contract AT(04-3)-34, P.A. 143. 相似文献
100.
A series of new 1,2,3-triazol derivatives, obtained by reaction of 8-azidotetrazol[1,5-a][1,8]naphthyridine with alkynes, is described. Some of the tested compounds showed activity against hypoxia in mice. 相似文献