Eighteen Peking ducklings were imprinted and tested for their tendency to emit distress calls during the presentation and withdrawal of the imprinted stimulus. A subsequent arrangement in which each distress vocalization led to a 5-second presentation of the imprinted stimulus resulted in an enhanced tendency to emit distress calls.

Animals↗

PubMed1966

Chemical thermogenesis in newborn infants: catecholamine excretion and the plasma non-esterified fatty acid response to cold exposure.

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Blood↗

PubMedDate not supplied

The clinical utility of Doppler ultrasound prior to arteriovenous fistula creation.

Arteriovenous fistula (AVF) is the preferred access for long-term hemodialysis, with superior long-term patency rates; however, early failure rates are significant. Recent evidence has brought into question the preferred site of AVF creation in many patient groups. A preoperative test that could reliably predict the outcome of a proposed AVF would be of great benefit. Doppler ultrasound has been the most extensively studied and widely used test to guide access creation. Accurate and validated measurements of internal vessel diameter, both arterial and venous, and blood flow in the upper extremity are obtainable by Doppler ultrasound. Studies evaluating the utility of Doppler ultrasound prior to AVF creation suggest that vessel size and blood flow are predictive of AVF outcome. An AVF created using a cephalic vein and/or radial artery smaller than 1.5-2.0 mm is likely to fail; such preoperative data may indicate that an upper arm AVF should be the primary access attempted. Further prospective studies are needed to evaluate the utility of Doppler ultrasound.

Arteriovenous Shunt, Surgical↗

PubMedDate not supplied

A description of the changing body composition of the growing premature infant.

Data from studies of two similar groups of premature infants were used to describe the changing body composition (BC) of a "typical" premature infant, 3 to 4 weeks old, gaining weight from 1,200 to 2,000 g and being fed its mother's expressed breast milk at a metabolizable energy intake of 93.6 kcal/kg/day. Serial measurements had been made of total body water (TBW), the extracellular fluid space (ECF), nitrogen balance, and gross energy balance in one group of premature (n = 17) infants and of total body potassium (TBK) in another group (n = 23); all infants studied weighed between 900 and 2,300 g. Equations relating TBW, ECF, and TBK to body weight were derived for estimating the content of these substances at body weights between 1,200 and 2,000 g. Protein content at 1,200 g body weight was estimated from measured TBK and N:K ratio (determined from the reference fetus) at this weight. Subsequent protein content was determined from average N accretion, determined from data of N balance, and carbohydrate and ash content were estimated from reference data. The remainder of the body weight was assumed to be fat. At 1,200 g, the proposed BC of the premature infant is 72.1% water, 10.7% protein, 14.9% fat, 1.9% ash, and 0.4% carbohydrate. At 2,000 g comparable figures are 67.8% water, 11.6% protein, 18.2% fat, 1.9% ash, and 0.5% carbohydrate. The description also provides estimates of the body cell mass (BCM) and intracellular fluid (ICF), the relationship of K to the BCM and ICF, and the energy balance of the growing premature infant.

Body Composition↗