Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Abstract: In order to test the widely held assumption that homeopathic medicines contain negligible quantities of their major ingredients, six such medicines labeled in Latin as containing arsenic were purchased over the counter and by mail order and their arsenic contents measured. Values determined were similar to those expected from label information in only two of six and were markedly at variance in the remaining four. Arsenic was present in notable quantities in two preparations. Most sales personnel interviewed could not identify arsenic as being an ingredient in these preparations and were therefore incapable of warning the general public of possible dangers from ingestion. No such warnings appeared on the labels.
Arsenic

Abstract: Combined two-dimensional and Doppler echocardiography has a high sensitivity and specificity for detection of isolated perimembranous ventricular septal defects. However, muscular or multiple ventricular septal defects may be difficult to diagnose with noninvasive methods, particularly in older children, necessitating angiography for accurate diagnosis. Detection of single and multiple ventricular septal defects with two-dimensional color flow mapping was compared with detection by standard two-dimensional imaging and Doppler. Both techniques were compared with four-chamber left ventricular angiography. Fifty-one patients (age 3 months to 25 years, mean 5.6 years) were studied. Eighteen had solitary ventricular septal defects, 18 had multiple ventricular septal defects, and 15 patients with intact ventricular septum served as a control group. At least one ventricular septal defect was detected by color Doppler and two-dimensional/Doppler methods in all patients with ventricular septal defect proved by angiography with no false positives. In the detection of multiple ventricular septal defects, the sensitivity of color Doppler was 72% and that of two-dimensional/Doppler was 38% (100% specificity in both). Color Doppler failed to identify multiple ventricular septal defects in five patients (two weighing less than 4 kg and three with reduced pulmonary blood flow). However, no large additional muscular defects were missed by imaging and color Doppler. Color Doppler is useful for the detection of ventricular septal defects and has higher sensitivity than two-dimensional/Doppler for multiple ventricular septal defects. The contribution of color Doppler appears to be in the detection of additional small muscular ventricular septal defects.
Adolescence

Abstract: The chronic effects of dietary protein on renal structure and function were studied in rats with normal and reduced renal mass. Control rats with two kidneys were compared with unilaterally nephrectomized rats, and with one and one-third nephrectomized rats obtained by unilateral nephrectomy and infarction of one-third of the remaining kidney. Rats at each level of renal mass were maintained on chow containing either 6% or 40% protein content. Separate cohorts of rats were studied four and eight months after ablation and institution of these dietary regimens. At both time intervals and at all levels of renal mass, rats fed the high protein diet had higher average values for GFR than comparable animals fed the low protein chow. Within each of the dietary regimens the animals with loss of renal mass developed greater prevalences of sclerotic glomeruli by eight months. Furthermore, at each level of initial renal mass, rats eating the high protein diet had a greater prevalence of sclerotic glomeruli than those on the low protein diet. Similarly, rats on the high protein diet had greater rates of protein excretion than those on the low protein diet at each degree of ablation. The prevalence of sclerosed glomeruli increased between four and eight months in each group. Thus, the extent of renal injury as manifested by proteinuria and glomerular sclerosis was directly related to the degree of initial loss of renal mass, and dietary protein restriction retarded these manifestations of injury across a wide range of initial renal mass.(ABSTRACT TRUNCATED AT 250 WORDS)
Animal