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31.
This paper presents probabilistic population projections for five regions of Asia (South Asia, Central Asia, China region, Pacific OECD and Pacific Asia) and Asia as a whole. Over this century, Asia will experience very heterogeneous demographic development: Central Asia is expected to almost double in population and South Asia will become by far the world’s most populous region, rapidly surpassing the China region. Simultaneously, the Pacific OECD countries are likely to shrink in population size and experience extreme population ageing. The proportion of the population aged 60 and above in these countries (with Japan having the greatest weight) is expected to reach 50 per cent of the total population (with the 95 per cent uncertainty interval ranging from 35 to 61 per cent). The China region will experience a more rapid speed of ageing, with the proportion aged 60 and above expected to increase by a factor of four from 10 per cent in 2000 to 39 per cent in 2100.  相似文献   
32.
In the first half of this century in many of today's developed countries, the proportion of voting age populations 65 years old or older will roughly double. As voting age populations age, the proportion of net contributors to national budgets (mainly through taxes) will fall and the proportion of net beneficiaries (mainly through public pension and health care benefits) will rise. By mid‐century in many wealthy countries, a near majority of electorates will become net beneficiaries of government expenditures, producing unprecedented changes in their political landscapes. We analyze three aspects of this phenomenon in Germany, Japan, and the United States.  相似文献   
33.
Russia has a history of pronatalist policies dating back to the 1930s. Two sets of pronatalist measures were implemented during the past 40 years. The one designed in the early 1980s proved to be a clear failure. Instead of raising fertility, completed cohort fertility declined from 1.8 births per woman for the 1960 birth cohort to 1.6 for the 1968 cohort. The government of President Putin became concerned with the dire demographic conditions of high mortality and low fertility in Russia in the 1990s and early 2000s. A comprehensive set of pronatalist measures came into effect in January 2007. The period total fertility rate increased from 1.3 births per woman in 2006 to 1.6 in 2011, which the authorities view as an unqualified success. An unbiased demographic evaluation as well as analyses of Russian experts reveals that apparently the measures mainly caused a lowering of the age at birth and shortening of birth intervals. It appears that any real fertility increase is questionable, i.e. cohort fertility is not likely to increase appreciably. The recent pronatalist measures are likely to turn out to be a failure.  相似文献   
34.
There are several approaches to assess or demonstrate pharmacokinetic dose proportionality. One statistical method is the traditional ANOVA model, where dose proportionality is evaluated using the bioequivalence limits. A more informative method is the mixed effects Power Model, where dose proportionality is assessed using a decision rule for the estimated slope. Here we propose analytical derivations of sample sizes for various designs (including crossover, incomplete block and parallel group designs) to be analysed according to the Power Model.  相似文献   
35.
Population Research and Policy Review - The concept of ‘replacement rate fertility’ [RRF] is widely known and referred to regularly in the popular, policy and academic literature....  相似文献   
36.
The purpose of this paper is to find out whether serum oxidizability potential measured before an exercise test (EXT) correlates with age and ischemic heart disease severity. Oxidizability potential was determined in 3 age groups, in gr. I patients < 45 years, in gr. II age range = 45 - 70years {\hbox{range}} = {45} - {7}0{\hbox{years}} , and in gr. III patients > 70 years. Included subjects had chronic ischemic heart disease (IHD) and underwent a symptom-limited EXT upon initiation of a cardiac rehabilitation program. The thermo-chemiluminescence (TCL) assay was used to assess serum oxidizability potential. This assay is based on heat-induced oxidation of serum, leading to the formation of electronically excited species in the form of unstable carbonyls, which further decompose into stable carbonyls and light energy (low chemiluminescence). Measured photons emission is represented by a kinetic curve which is described by its amplitude and slope (=ratio). We assessed the correlations of TCL ratio with age, exercise duration, metabolic equivalents (METS), maximal heart rate (mHR), maximal systolic BP, >1 mm S-T depression, diabetes, hypertension, smoking, left ventricular ejection fraction (LVEF)> or <40%, previous myocardial infarction, and aorto-coronary bypass surgery. A high TCL ratio (%) correlated well with METS (r = 0.82), mHR (r = 0.77) and with exercise-induced S-T segment shift (r = 0.86, p < 0.05). A lower serum oxidizability potential, expressed as a low TCL ratio, thus suggestive of a previous high oxidative stress, was found in the two older age groups compared to gr. I (<45 years), p = 0.041, and in particular, in gr. III patients with low LVEF%. The TCL ratio (%) in gr. III was 188.7 ± 14.5, 192 ± 17 in gr. II, and 214 ± 13 in gr. I (p < 0.05), and was 166 ± 13.1 in gr. III with LVEF < 45% as compared to 271 ± 15.7 in gr. I patients with LVEF > 45% (p < 0.01). A trend for lower TCL ratio (%) was found in diabetic, hypertensive, and post-coronary bypass surgery patients. A paradoxically low TCL ratio (low oxidizability potential) was observed in patients without S-T depression compared to patients with S-T depression (189 ± 22 vs. 201 ± 15, p = NS), due to the fact these patients had a much lower LVEF% and a lower exercise capacity. Serum oxidizability potential is associated with age, EXT parameters, results, and IHD severity. TCL ratio is an “easy-to-measure marker” that might be incorporated into risk assessment and prediction in aged IHD patients.  相似文献   
37.
While global polio eradication requires tremendous efforts in countries where wild polioviruses (WPVs) circulate, numerous outbreaks have occurred following WPV importation into previously polio‐free countries. Countries that have interrupted endemic WPV transmission should continue to conduct routine risk assessments and implement mitigation activities to maintain their polio‐free status as long as wild poliovirus circulates anywhere in the world. This article reviews the methods used by World Health Organization (WHO) regional offices to qualitatively assess risk of WPV outbreaks following an importation. We describe the strengths and weaknesses of various risk assessment approaches, and opportunities to harmonize approaches. These qualitative assessments broadly categorize risk as high, medium, or low using available national information related to susceptibility, the ability to rapidly detect WPV, and other population or program factors that influence transmission, which the regions characterize using polio vaccination coverage, surveillance data, and other indicators (e.g., sanitation), respectively. Data quality and adequacy represent a challenge in all regions. WHO regions differ with respect to the methods, processes, cut‐off values, and weighting used, which limits comparisons of risk assessment results among regions. Ongoing evaluation of indicators within regions and further harmonization of methods between regions are needed to effectively plan risk mitigation activities in a setting of finite resources for funding and continued WPV circulation.  相似文献   
38.
This paper surveys Soviet literature of fuzzy set theory and applications. A bibliography containing about 250 titles is presented.  相似文献   
39.
40.
Historical life tables for developed countries are analysed in order to present the epidemiological transition in terms of Brass's logit system. The results of this analysis are used to determine the range of the two Brass model parameters consistent with historical life tables. This range also includes human life tables that could have been observed in pre-transitional stages or could occur in the future.  相似文献   
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