Comparison of relative coronary Doppler flow velocity reserve to stress myocardial perfusion imaging in patients with coronary artery disease.

To compare relative coronary artery vasodilator reserve (rCVR = CVRtarget/CVRreference) to myocardial perfusion stress imaging, 48 patients with coronary artery stenoses (61% +/- 16%; mean, +/- SD; range, 30%-91%) had measurements of target and reference vessel CVR (Doppler-tipped guidewire). rCVR was computed and compared to stress 201thallium or (99m)technetium-sestamibi myocardial tomography. Compared to 24 patients with negative stress imaging studies, 24 patients with positive stress studies had angiographically more severe stenoses (74% +/- 13% vs. 44% +/- 24%; P = 0.0005) with lower CVR(target) (1.68 +/- 0.55 vs. 2.46 +/- 0.74; P = 0.002) and lower rCVR (0.72 +/- 0.22 vs. 1.0 +/- 0.26; P < 0.003). Based on receiver-operator characteristic (ROC) cut points (CVR > 1.9; rCVR > 0.75), compared to CVR, rCVR had similar agreement (Kappa 0.54 vs. 0.50), sensitivity (63% vs. 71%), specificity (88% vs. 83%), and positive predictive value (83% vs. 81%) with myocardial perfusion tomography. A concordant CVRtarget/rCVR only slightly increased sensitivity, specificity, and positive predictive values (77%, 90%, and 87%, respectively). Although rCVR, like CVR, correlates with stress myocardial perfusion imaging results, rCVR did not have significant incremental prognostic value over CVR alone for myocardial perfusion imaging. However, rCVR does provide additional information regarding the status of the microcirculation in patients with coronary artery disease and complements the CVR for lesion assessment.

Emerging population issues in Africa.

"The rate of population growth in Africa has increased significantly because of large decreases in mortality without significant decline in fertility rates. The factors leading to high fertility rates are explored as are the social issues that result because of the high proportion of children. Further, although mortality rates in Africa have been improving, they continue to lag behind the rest of the world. Some of the reasons behind these and other aspects of the demographic situation are explored." (SUMMARY IN FRE)

Historical population estimates for Egypt: a critical review.

"This article attempts to piece together historical population estimates for Egypt and to assess their credibility, starting from Pharaonic times and continuing through the Greek and Roman eras and the Middle Ages.... While many doubts are raised concerning several of the estimates, the article suggests that population size in Egypt responded to societal conditions and that the demographic situation was at its worst during the Middle Ages. It improved only after the role of the Mamluks and the Ottomans had been terminated, early in the nineteenth century."

Demographic estimates and projections.

PIP: The periodic assessment of global population growth from the past to the future has been one of the UN's most important contributions to member states and many other users. Available data and applicable analysis and projection methods were very limited in 1947, when the 1st global population estimates and projections were attempted. The 1st contributions of the Commission were manuals for these functions. Throughout the 1950s, 4 regional reports on Central and South America; Southeast Asia; and Asia and the far East were published. UN studies during this period tended to group regions by their position on a continuum of the demographic transition. Rough but alarming projections of population growth appeared. Projection technics were refined and standardized in the 1960s, and the demand grew for more specialized technics, e.g. dealing with urban/rural populations; the labor force; and other elements. The availability of computer technology at the end of the decade multiplied the projection capabilities, and the total population projections for the future were larger than ever. The 1970s projections, based on the more accurate and widely covered baseline data which had become available in developing countries, were also aided by more powerful and innovative indirect estimation technics; better software, and computers with larger capacities. By 1982, only a few countries were left with a total lack of data. A revision of estimates and projections is now undertaken biennially, incorporating the latest available data, utilizing advanced analytical methods and computer technology. Methodological manuals have been produced as the by-product of the revisions. UN demographic estimates and projections could be further improved by injection of a probabilistic element and the inclusion of economic factors. Roles for the future include maintenance of regional and interregional comparability of assumptions.^ieng

Latin American population prospects in the next fifteen years.

Abstract This paper discusses some of the results of population projections by age and sex for the period 1965-85 which were prepared some years ago for Latin American countries. Despite the limitation of the data there are several short-range implications which deserve attention. The area which had the highest rate of growth among all the major areas of the world during the last 50 years, is expected to maintain a stable rate during the next 15 years. Though some fertility decline is anticipated, it is bound to be slower, in general, than expected in East and South Asia where cultural factors are not as strong. The gain in mortality is also expected to be relatively slow, but this is only because mortality has already reached fairly low levels compared to Asia and Africa. However, because of the young age distribution, the area is expected to have in the near future crude death rates which are so low that they have probably not been experienced before in normal human populations. A simple grouping of the population into pertinent age-sex groups gives information which undoubtedly raises serious questions concerning the adequacy of the measures which are now being taken or planned to meet the various needs of different population categories. For instance, in addition to existing problems, the economies will have to face the problem of absorbing within the next 15 years the anticipated increases of about 84 million in the labour force, the educational systems will have to provide for the schooling of about 28 million additional children of school age, and the planners for social and economic development will have to consider the measures necessary to face an increase of about 56% in the number of females of reproductive ages. The figures show clearly that the problems have different dimensions in different regions, with those of Central America being perhaps particularly serious.

Higher female than male mortality in some countries of South Asia: a digest.

PIP: A statistical study was made of sex ratios and mortality in Ceylon, Pakistan, and India. Contrary to general expectations, female mortality was higher than male mortality. A greater divergence in the sex ratio was found with increased age. Female emigration and abnormal sex ratios at birth are discounted as explanations of the phenomenon. It is considered that underenumeration of females in the census and higher female mortality rates, especially during the reproductive years and childhood, are responsible for the inverted sex ratio. The projected sex ratios for these countries are not reflected in the model life tables derived from international experience.^ieng

A study of differential fertility in bombay.

This study is based on special tabulations of the "order of pregnancy," as reported on the birth certificate, according to mother's age, locality, and religion and father's state of birth and duration of stay in Bombay, India. The sample consists of 50 percent of the births registered in 1960 in Bombay (where birth registration has a fairly high degree of completeness).Despite the limitations of statistical information on the complex of factors influencing fertility, it wasfound that three indicators derived from the 1961 census could numerically account for 51 percent of the total variance of the parity averages in the sections of Bombay. Overcrowding (which is an indicator of the level of living) had the strongest influence and accounted alone for 44 percent of the variance. Knowledge of thereligious patternraised thepercentage to49, whileinclusionof theilliteracy measure added only another two to this percentage.An assessment of fertility differences by religious groups, as well as by place of origin of the father, is then carried out. The data show significant differences among religious groups, with Moslems and Buddhists having the highest parity averages, followed by Hindus and Jains. A considerably lower level is shown by Christians, but the lowest parity level is that of the small Parsi community. Mothers whose husbands were born in the south and east were found to show the lowest parity level, while those who have north-born husbands showed the highest level.Finally, the data show consistent increase in age-standardized parity averages with increase of the duration of stay in Bombay. This pattern is observed for each of the three main geographic regions of origin. While this increase is difficult to explain on the basis of the available data, the fact that the pattern of parity differences among regions persists from one duration group to the next lends support to the conclusion that little assimilation seems to have been taking place.