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At least 19 recordsLinked to original sources
PubMed1978

Blood viscosity in the normal newborn baby.

A viscometer was tested and the results were found to be accurate and reproducible for the ranges encountered in neonates. The viscosity was determined in 80 cord blood samples and the mean and 2 standard deviations (2SD) were calculated at each shear rate. Changes in viscosity increased from birth to 12 hours, and then gradually decreased over the next 72 hours. The results are in keeping with the accepted normal values in the newborn.

Blood Viscosity↗
PubMed1977

Elective induction of labor conducted under lumbar epidural block. I. Labor induction by amniotomy and intravenous oxytocin.

Epidural analgesia (bupivacaine) was administered during labor after amniotomy, in some cases supplemented by intravenous oxytocin. A higher incidence of transient uterine hypertonus was seen after blocking. Fetal heart rate changes mainly took the form of bradycardia (in association with uterine hypertonus). At birth, the maternal biochemical condition was characterized by a lower degree of metabolic acidosis, compared to normal unanesthetized controls. The fetuses displayed a slight degree of hypoxia and hypercapnia. The mechanisms underlying these modifications are discussed. Epidural blockade in combination with elective induction of labor, whether or not supplemented by intravenous oxytocin, may carry a risk. Its magnitude is considered acceptable for both mother and fetus provided they are constantly under close surveillance, limited amounts of bupivacaine are administered and the second stage of labor is kept short. However, some warnings against epidural analgesia apply to patients with placental insufficiency and very active labor.

Adult↗
PubMed1978

Discriminative control of the vaginal vasomotor response.

With use of a discriminative control procedure and operant techniques, women significantly increased their vaginal pulse amplitude (produced vaginal vasodilation) but did not significantly decrease vaginal pulse amplitude (produce vaginal vasoconstriction). Acquisition of vaginal pulse amplitude control was rapid with no significant improvement over trials or the 5 experimental days. Specificity of vaginal pulse amplitude control occurred in relation to the other vasomotor responses, including vaginal blood volume and digital pulse amplitude. Vagnial pulse amplitude changes were not related to somatic-muscular, respiratory, or heart-rate changes. Women who used oral contraceptives were better able to control vaginal pulse amplitude than women who used other forms of birth control. Although the sexual behavior of these two groups and did not differ, women in the latter group tended to be more clitorally oriented.

Adolescent↗
PubMed1977

A component analysis of recent fertility decline in singapore.

To aid in achieving demographic goals, since 1968 the government of Singapore has passed a series of laws designed to limit family size. Policies were instituted in 1968 to discourage couples from having more than three children; policies introduced in 1973 discouraged having more than two. Trends in fertility rates and in the numbers of abortions and sterilizations in recent years are consistent with the intent of these social policies. Decline in third and subsequent births was the most important factor in fertility decline after 1972, and the numbers of abortions and sterilizations undergone by higher parity women have increased substantially sin"e 1970. Although other factors have affected fertility in Singapore, the data suggest that the disincentives have played a role in continued fertility decline in recent years.

Abortion, Legal↗
PubMed1978

Fertility and family planning in rural northern Thailand.

From the mid-1960s to the mid-1970s, when fertility was declining in Thailand as a whole, especially rapid declines occurred in Northern Thailand, but they did not occur uniformly in all the region's provinces. The Northern Thailand Fertility Study, initiated in 1975 to study the reported fertility changes, gathered data in two provinces: Chiang Mai, where fertility decline has been quite rapid, and Chiang Rai, which experienced relatively little decline until 1974. This preliminary report discusses fertility levels and trends in the two provinces, fertility experience and expectations of respondents, attitudes toward and knowledge of family planning, and contraceptive practice. The results suggest that most of the difference in fertility decline is related to the different level of family planning program activity in the two provinces.

Abortion, Spontaneous↗
PubMed1979

Postnatal effects of prenatal sound stimulation in the guinea pig.

Pregnant guinea pigs were stimulated with a natural sound alien to their species. Postnatally the response of their young to this sound was compared with that of unstimulated controls. All young were tested with a series of the alien sounds followed by series of guinea pig calls. Heart rate changes showed that prenatally stimulated young responded less to the alien sounds than did controls, whereas both groups responded equally to guinea pig calls. Response of controls diminished during daily test sessions and over the five test days and comparison with an older control group showed that this was due to repetition of the stimulus. It is suggested that the response of prenatally stimulated animals had waned before birth.

Animal Communication↗
PubMed1976

Beta-glucuronidase isozyme patterns of experimental hepatomas of rats.

Beta-Glucuronidase isozymes in rat tissues were separated by electrophoresis on cellulose acetate membranes. Using this method, beta-glucuronidase isozyme patterns were studied in normal rat liver and experimental hepatomas with different growth rates. Changes of isozyme patterns during postnatal development were also studied in rat liver. Normal rat liver contained six types of beta-glucuronidase, numbered I to VI in order to decreasing mobility to the cathode. Type II beta-glucuronidase stained most intensely and was detected in all the cells examined. The isozyme patterns of Morris hepatomas, which are slowly growing and not highly deviated, resembled that of normal rat liver but lacked definite Type III beta-glucuronidase. Yoshida ascites hepatomas, which are rapidly growing and highly deviated, contained only Type II, but some had Types II, V, and VI beta-glucuronidase. Embryonal liver just before birth contained only Type II, but with increase in activity during development after birth, minor bands of Type I and Types III to VI beta-glucuronidase appeared successively to complete the adult pattern.

Animals↗
PubMed1976

Cardiovascular effects of electrical stimulation of the forebrain in the fetal lamb.

Modified stereotaxic techniques were applied to fetal lambs during the latter third of gestation. Electrical stimulation in the region of the hypothalamus in 10 acute experiments was associated with three patterns of arterial blood pressure and heart rate changes: a pressor-tachycardia response; a pure tachycardia response (abolished by propranolol); and a pure bradycardia response (abolished by atropine). The pressor-tachycardia response was examined in detail in 13 chronic preparations (115-135 days of gestation at operation). The systolic arterial blood pressure increase was never greater than 35 mm Hg and was probably blunted by the large noninnervated placental circulation. This pressure increase was abolished by phentolamine and was thus mediated by stimulation of alpha-adrenergic receptors. The initial tachycardia was prevented by propranolol and was due to beta-adrenergic stimulation. The tachycardia was followed in a few seconds by a bradycardia, abolished by atropine and possibly a vagal baroreflex. The pressor-tachycardia response was accentuated in two lambs who were delivered spontaneously and were studied after birth. These studies indicate that a suprabulbar neural framework exists in the fetal lamb for influencing the cardiovascular system from as early as 90 days of gestation.

Adrenergic beta-Antagonists↗
PubMed1979

Survey of abortion providers in Seoul, Korea.

A survey of abortion providers in Seoul in late 1977 reveals a threefold increase in the rate of abortion and a greater than threefold rise in the ratio of abortions to live births since 1970. The survey findings also show that the overwhelming proportion of these abortions are performed in private clinics, by obstetrician-gynecologists, during the first trimester. The Seoul figures, which are similar to those of Romania and are higher than those of Japan in the early 1960s, indicate that abortion has contributed substantially to Korea's reduced fertility.

Abortion, Legal↗
PubMed1978

What will 1984 be like? Socioeconomic implications of recent twists in age structure.

Since 1940, under conditions of restricted immigration and high and sustained growth in aggregate demand, shifts in the relative number of younger versus older adults have had a pervasive impact on American life. Before 1960, younger males were in increasingly short supply and their relative economic position substantially improved; after 1960, the opposite was true. Since the early sixties, as the relative condition of young adults has deteriorated, marriage has been increasingly deferred and fertility reduced. The labor force participation of young women has risen at above average rates, and that of older women has risen at below average rates. Changes in the age structure of the working age population have also contributed to a combination of rising unemployment and accelerating inflation. Cohort divorce rates, suicide among young males, crime rates, and political alienation have worsened. The rise in college enrollment rates has been interrupted, and SAT scores have declined. In contrast, in the period 1940-1960, changes in these various magnitudes were typically of a more favorable sort. The United States is now at the start of a new period of growing scarcity of young adults as a result of the birth rate decline that set in after 1960. This implies that the 1980s will see a turnaround or amelioration in a wide variety of these social, political, and economic conditions, some of which have been taken as symptomatic of a hardening social malaise.

Adult↗