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Biomedical subjects

J Villar

Publications and source records attributed to J Villar.

At least 217 records · Page 12Linked to original sources
PubMed1981

Rise of blood pressure in calcium-deprived pregnant rats.

It has been postulated that calcium uptake is inversely related to blood pressure (BP) in animals and pregnant women. To test this hypothesis, 34 female, 142-day-old Wistar rats were studied prospectively. They were randomly assigned to either a calcium-free diet (16 rats) or a normal diet (18 rats). Weekly measurements of tail systolic BP showed a statistically significant increase in BP in the calcium-free group after 6 weeks of treatment. After 9 weeks on this diet, the animals were mated. Five in the control group and six in the calcium-free group became pregnant. Thereafter, both of these subgroups (pregnant and nonpregnant calcium-free diet) continued with significantly higher BP until they were put to death. Blood samples taken at the end of the study showed significantly lower values of calcium/magnesium (Ca/Mg) ratio, but higher inorganic phosphate in the group consuming a calcium-free diet. Blood pressure during the last 3 weeks of the study was significantly inversely correlated with the blood Ca/Mg ratio and directly correlated with magnesium and inorganic phosphate values. This article supports the hypothesis that a low-calcium diet is associated with high BP in pregnant and nonpregnant female rats.

Animals↗
PubMed1978

Diagnosis of intrauterine growth retardation by a simple clinical method: measurement of uterine height.

Generally there is a tendency to underrate the value of uterine height in the diagnosis of intrauterine growth retardation (IUGR). This fact is probably due to the lack of standard normal values for this measurement. In a group of 298 healthy pregnant women, the 10th, 50th, and 90th percentile were calculated by week of amenorrhea. Uterine height was measured with a nonelastic measuring tape, from the symphysis pubis to the fundus uteri. With the use of these standard values the predictive value of the method was established. Of 44 neonates with low birth weight for gestational age, 38 had a uterine height below the 10th percentile (sensitivity 86%). Six cases of IUGR were not diagnosed by this method. Of 95 neonates with adequate birth weight, 85 had uterine values above the 10th percentile (specificity 90%). Ten (10%) of these were predicted as low birth weight but were born with adequate weight. The uterine height measurement is shown to be a very good method for detecting IUGR. It can be used as a screening test to detect impairment in fetal growth and to make early referral of those pregnancies.

Adult↗
PubMed1976

Differences among cattle and farms as related to beef cow reproduction in the eastern plains of Colombia.

In the tropical savannas of Colombia, the Llanos Orientales, a field survey of 40 beef herds leased by farmers through a cooperative indicated that these herds had mean annual calving rates of 52 and 55 per cent in the Plains and Piedmont zones, respectively. Within zones, very large differences in reproductive rates were found between herds. The differences seemed to be associated with the soils and climates of the areas, condition and weight of cows and breed of cow. Only 9 to 13 per cent of nursing cows were found to be pregnant. Conception was seasonal, occurring mostly in the dry and early rainy seasons. Control of the time of weaning of calves, routine mineral supplementation and improved pasture management appeared to offer immediate possibilities for economically improving output of calves.

Animal Feed↗