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1.
Abstract

The relationships between length of the interpregnancy interval, outcome of the pregnancy preceding the interval, sex of the infants, pregnancy order, maternal age, and maternal history of previous child deaths and neonatal and postneonatal mortality were explored in a rural Bangladeshi population using a multiple regression analysis. Specific interactions between the interpregnancy interval, outcome of the pregnancy preceding the interval, sex of the infants, and history of previous child deaths were examined. An inverse relationship was observed between postneonatal mortality and the length of the interpregnancy interval when the pregnancy preceding the interval was a surviving infant. No such trend was observed for neonatal mortality. Post‐neonatal mortality rates among children whose mothers had experienced two or more previous child deaths were essentially the same as that for infants whose mothers had experienced 0–1 child deaths when the interpregnancy intervals were more than 24 months. Although female infants have a lower neonatal mortality than male infants, the neonatal mortality rate for female infants conceived less than twelve months following a male infant birth was higher than for a male infant conceived less than twelve months following another male infant birth. Post‐neonatal mortality is consistently higher for female compared to male infants in all interval categories.  相似文献   

2.
Abstract: Baboons are widely used in biomedical research. Although it is widely held that Papio hamadryas breed well in captivity, each established colony has a different reproductive success often hypothesised to be due to husbandry practices. The National Baboon Colony in Australia is a unique colony that houses Papio hamadryas to mimic that structure seen in the wild. In this article; we have analysed their reproductive parameters and neonatal outcomes. The success of the colony husbandry practices was demonstrated by lack of maternal mortality, low foetal morbidity, and known maternal and paternal linage.  相似文献   

3.
A life history strategy that favours somatic growth over reproduction is well known for long-lived iteroparous species, especially in unpredictable environments. Risk-sensitive female reproductive allocation can be achieved by a reduced reproductive effort at conception, or the subsequent adjustment of investment during gestation or lactation in response to unexpected environmental conditions or resource availability. We investigated the relative importance of reduced investment at conception compared with later in the reproductive cycle (i.e. prenatal, perinatal or neonatal mortality) in explaining reproductive failure in two high-density moose (Alces alces) populations in southern Norway. We followed 65 multiparous, global positioning system (GPS)-collared females throughout the reproductive cycle and focused on the role of maternal nutrition during gestation in determining reproductive success using a quasi-experimental approach to manipulate winter forage availability. Pregnancy rates in early winter were normal (≥0.8) in all years while spring calving rates ranged from 0.4 to 0.83, with prenatal mortality accounting for most of the difference. Further losses over summer reduced autumn recruitment rates to 0.23–0.69, despite negligible predation. Over-winter mass loss explained variation in both spring calving and autumn recruitment success better than absolute body mass in early or late winter. Although pregnancy was related to body mass in early winter, overall reproductive success was unrelated to pre-winter body condition. We therefore concluded that reproductive success was limited by winter nutritional conditions. However, we could not determine whether the observed reproductive allocation adjustment was a bet-hedging strategy to maximise reproduction without compromising survival or whether females were simply unable to invest more resources in their offspring.  相似文献   

4.
Background Causes of infant death remain unknown in significant proportions of human and non‐human primate pregnancies. Methods A closed breeding colony with high rates of infant mortality had pregnancies assessed (n = 153) by fetal measurements and maternal characteristics. Infant outcome was classified as neonatal death (stillborn or died <48 hours from birth), postnatal death (died 2–30 days) or surviving (alive after 30 days). Results Fetal size did not predict outcome. Poor maternal glycemic control and low social ranking increased odds for adverse outcome (OR = 3.72, P = 0.01 and 2.27, P = 0.04, respectively). Male sex was over‐represented in stillbirths (P = 0.04), and many were macrosomic, but size did not associate with maternal glycemic control measured as glycated hemoglobin A1c. Postnatally dead infants were smaller (P < 0.01), which associated with behavioral factors and glycemic control. Conclusions Fetal growth estimates predicted gestational age but not fetal outcome. Maternal social status and metabolic health, particularly glycemic control, increased risks of adverse pregnancy outcome.  相似文献   

5.
A breeding colony of cynomolgus macaques (Macaca fascicularis), composed of imported and colony-born animals and established for 9 years, was evaluated for maternal factors associated with reproductive failure. The factors evaluated included age, gravidity, parity, origin, previous stillbirths, clinical incidents and type of housing. The effects of each factor on pregnancy rate (PR), stillbirth rate (SR), infant mortality rate (IMR) and pregnancy success (PS) were evaluated. The overall colony rates were: PR = 53%, SR = 22%, IMR = 22%, and PS = 60%. Neonatal death rate for the group was 12%. Pregnancy rate was most affected by maternal factors. Clinical incidents occurring during pregnancy were associated with a significant increase in the stillbirth rate, but did not affect infant mortality rate. Maternal age did not affect any of the measures of reproductive output. Pregnancy rate peaked at 6-8 years of age and decreased thereafter, while pregnancy success peaked at 9-11 years of age. Gravidity and parity had a positive linear relationship with pregnancy rate.  相似文献   

6.

Background

Maternal immunization has gained traction as a strategy to diminish maternal and young infant mortality attributable to infectious diseases. Background rates of adverse pregnancy outcomes are crucial to interpret results of clinical trials in Sub-Saharan Africa.

Methods

We developed a mathematical model that calculates a clinical trial''s expected number of neonatal and maternal deaths at an interim safety assessment based on the person-time observed during different risk windows. This model was compared to crude multiplication of the maternal mortality ratio and neonatal mortality rate by the number of live births. Systematic reviews of severe acute maternal morbidity (SAMM), low birth weight (LBW), prematurity, and major congenital malformations (MCM) in Sub-Saharan African countries were also performed.

Findings

Accounting for the person-time observed during different risk periods yields lower, more conservative estimates of expected maternal and neonatal deaths, particularly at an interim safety evaluation soon after a large number of deliveries. Median incidence of SAMM in 16 reports was 40.7 (IQR: 10.6–73.3) per 1,000 total births, and the most common causes were hemorrhage (34%), dystocia (22%), and severe hypertensive disorders of pregnancy (22%). Proportions of liveborn infants who were LBW (median 13.3%, IQR: 9.9–16.4) or premature (median 15.4%, IQR: 10.6–19.1) were similar across geographic region, study design, and institutional setting. The median incidence of MCM per 1,000 live births was 14.4 (IQR: 5.5–17.6), with the musculoskeletal system comprising 30%.

Interpretation

Some clinical trials assessing whether maternal immunization can improve pregnancy and young infant outcomes in the developing world have made ethics-based decisions not to use a pure placebo control. Consequently, reliable background rates of adverse pregnancy outcomes are necessary to distinguish between vaccine benefits and safety concerns. Local studies that quantify population-based background rates of adverse pregnancy outcomes will improve safety assessment of interventions during pregnancy.  相似文献   

7.
In Matlab thana, a rural area of Bangladesh, there is a substantial deficit of males of reproductive age owing to urban migration of males who leave their families behind. These men nevertheless return to visit their families frequently. 30% of the births in this area occur to families with migrant fathers: neonatal mortality rates in these families are nearly double those of families with non-migrant fathers. This high risk, in turn, interacts with educational attainment and maternal nutrition. Only those migrant families where mothers have no education or have low body weight experience high neonatal mortality rates. Psychological stress during pregnancy, probably caused by fear and anxiety related to the husband's absence may in part be responsible for such differential risk during the neonatal period.  相似文献   

8.
At both extremes of reproductive phase female pregnancy outcome is described as poor. Beside a high rate of anovulatory cycles, pregnancies at these phases of the reproductive span are considered as risky for obstetric complications, and increased maternal and newborn morbidity and mortality. In the present study the associations between the age as well as somatic characteristics such as prepregnancy weight, stature, pelvic dimensions and pregnancy weight gain of 10765 women ageing between 12 and 49 years and newborn body dimensions and the mode of delivery as well as uterine child presentation were analysed. With increasing maternal age, maternal and newborn body dimensions increased significantly. Furthermore, extremely young mothers showed the lowest rates of caesarean sections, while mothers older than 40 years experienced the significantly highest rate of caesarean sections. Regarding newborn weight status, for mothers older than 35 years the highest rate of low weight newborns (< 2500 g) and the highest rate of macrosome newborns (> 4000 g) were found. Special risks were found in mothers older than 35 years, so the lower rates of ovulatory cycles during this phase of life may be interpreted as an adaptation to increased risks for complications and poor pregnancy outcome.  相似文献   

9.
Reproductive data are presented for female Papio papio housed in the Zoological Park of Paris and are compared with previously published data from free‐ranging populations of other baboon species. The results indicate similar intermenstrual intervals and durations of sexual swelling. Sexual swelling and pregnancy are accelerated in captivity, while postpartum amenorrhea and interbirth interval are reduced. Interbirth intervals in P. Papio were short, approximately 13 months in the case of viable, surviving infants and approximately 11 months in the case of stillbirth or neonatal mortality. The shorter interval may represent the lower physiological limit, and the generally shorter interbirth interval reported here may be explained by lower stress and reduced maternal investment costs in the captive environment. Paracallosal skin color variations during the menstrual cycle were influenced by parity, but sexual swelling patterns were not. The paracallosal skin changes might be used by males as a cue to females' reproductive status. Am. J. Primatol. 47:67–74, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   

10.
The aim of this study was to evaluate the effect of Himatanthus sucuuba on the maternal reproductive outcome and fetal anomaly incidence in rats. Pregnant rats were randomly divided into three experimental groups as follows: Control = treated with water (vehicle), treated 250 = treated with H. sucuuba at dose 250 mg/kg, and treated 500 = treated with H. sucuuba at dose 500 mg/kg. The rats were orally treated, by gavage, with H. sucuuba or vehicle (water) during preimplantation and organogenic period (from gestational day 0–14). At day 21 of pregnancy, all rats were killed to obtain maternal–fetal data. The treatment with H. sucuuba at dose of 250 mg/kg caused reduction in placental efficiency and an increase preimplantation loss rate and placenta weight compared with the control. The treated 500 group presented a significant decrease in maternal weight gain, maternal weight gain minus gravid uterus weight, fetal weight, and placental efficiency compared with the control. In this group, there was a decrease in body weight at day 20 of pregnancy and metacarpus ossification and an increase in the preimplantation loss rate and skeletal anomalies compared with other groups. Himatanthus sucuuba extract caused intrauterine growth restriction, preimplantation loss, and developmental delay in the high doses tested  相似文献   

11.
Knowledge on reproductive success is vital for successful management of large ungulates and is often measured by means of observing surviving offspring. In harvested ungulates, postmortem investigations of reproductive organs are used to estimate reproductive potential by obtaining ovulation rates and fetus numbers. However, there are differences in numbers of offspring observed, fetal/embryo counts, and ovulation rates. We hypothesize that the discrepancy between estimated reproductive potential and reproductive outcome in large ungulates is not only due to ova loss but also due to embryonic mortality. We investigated reproductive status in early pregnancy by sampling hunter-harvested moose (Alces alces) in southern Sweden from 2007 to 2011. In all, 213 reproductive organs were examined postmortem, and in confirmed pregnant moose (n?=?53), 25 % (19 of 76) embryos were nonviable and 6 % of ova was unfertilized. The discrepancy between the ovulation rate of all pregnant moose (1.49) and the number of expected offspring per pregnant female, when embryonic mortality and unfertilized oocytes were accounted for (1.08), was 27.5 %. An association between inflammation of the inner mucous membrane (endometritis) of the moose's uterus and embryonic mortality was observed. This is the first comprehensive report of embryonic mortality and endometritis in moose. The observed discrepancy between ovulation rates and early embryonic development/survival shows that ovulation rates are indicative but not accurate estimates of moose reproductive rate. The use of ovulation rates as a sole estimator of future offspring rates may lead to an overharvest of a managed moose population.  相似文献   

12.
One hundred seventy‐two medical records of captive jaguars (Panthera onca) were examined from 30 American Zoo and Aquarium Association (AZA) institutions housing jaguars between 1982–2002. The study determined common causes of morbidity and mortality, and the influence of age, gender, and melengestrol‐acetate (MGA) exposure on these rates. The most common causes of morbidity in captive jaguars were found to be dental, gastrointestinal, integumentary, and musculoskeletal diseases. Prevalence of types of disease varied with age, with older animals experiencing a higher prevalence of multiple types of disease. Females developed reproductive disease more frequently than males, and the data suggest that MGA exposure increased the risk of developing female reproductive disease. The most common causes of mortality were reproductive diseases in females and musculoskeletal diseases in males. There was a high rate of neonate and pediatric mortality, primarily due to stillbirths or unexplained neonatal death, trauma, and pneumonia. Other diseases or clinical signs that seemed remarkable were a high prevalence of episodes of epistaxis among young, as well as old, jaguars. Based on these findings, management suggestions for the captive jaguar population are presented. Zoo Biol 0:1–12, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   

13.
《Epigenetics》2013,8(4):409-414
Prenatal exposure both to maternal psychiatric illness and psychiatric medication has been linked with adverse child outcomes that affect physiological, emotional and psychiatric development. Studies suggest that epigenetic mechanisms, such as DNA methylation, may facilitate these effects. In this report, we explore the association between maternal psychiatric illness and treatment during pregnancy and neonatal DNA methylation patterns in a prospectively-characterized clinical cohort of 201 dyads. Associations between the percent of umbilical cord blood DNA methylated at 27,578 CpG sites and maternal psychiatric diagnosis, symptoms and antidepressant use were evaluated by fitting a separate linear mixed effects model for each CpG site. There were no significant changes in neonatal DNA methylation attributable to maternal psychiatric diagnosis or depressive symptoms during pregnancy. Exposure to an antidepressant medication was associated with differential methylation of CpG sites in TNFRSF21 and CHRNA2 (false discovery rate < 0.05), but the average difference in methylation for both CpG sites was less than 3% between each group. The results were not specific to type of antidepressant or duration of the exposure. This study suggests that there are no large effects of maternal psychiatric illness, depressive symptoms or prenatal exposure to antidepressants on neonatal DNA methylation. Delineation of the influence of maternal psychiatric illness and pharmacological exposures on the developing fetuses has critical implications for clinical care during pregnancy.  相似文献   

14.
Objective: Pre‐pregnancy obesity poses risks to both pregnant women and their infants. This study used a large population‐based data source to examine trends, from 1993 through 2003, in the prevalence of pre‐pregnancy obesity among women who delivered live infants. Research Methods and Procedures: Data from the Pregnancy Risk Assessment Monitoring System in nine states were analyzed for trends in pre‐pregnancy obesity (BMI > 29.0 kg/m2) overall and by maternal demographic and behavioral characteristics. Pre‐pregnancy BMI was calculated from self‐reported weight and height on questionnaires administered after delivery, and demographic characteristics were taken from linked birth certificates. The sample of 66,221 births was weighted to adjust for survey design, non‐coverage, and non‐response, and it is representative of all women delivering a live birth in each particular state. The sampled births represented 18.5% of all births in the United States. Results: Pre‐pregnancy obesity increased 69.3% during the study period, from 13.0% in 1993 to 1994 to 22.0% in 2002 to 2003. The percentage increase ranged from 45% to 105% for individual states. Subgroups of women with the highest prevalence of obesity in 2002 to 2003 were those who were 20 to 29 years of age, black, had three or more children, had a high school education, enrolled in Women, Infants, and Children, or were non‐smokers. However, all subgroups of women examined experienced at least a 43% increase in pre‐pregnancy obesity over this time period. Discussion: The prevalence of pre‐pregnancy obesity is increasing among women in these nine states, and this trend has important implications for all stages of reproductive health care.  相似文献   

15.
OBJECTIVES: To study reproductive pattern and perinatal mortality in rural Tamil Nadu, South India. DESIGN: Community based, cross sectional questionnaire study of 30 randomly selected areas served by health subcentres. SETTING: Rural parts of Salem District, Tamil Nadu, South India. SUBJECTS: 1321 women and their offspring delivered in the 6 months before the interview. MAIN OUTCOME MEASURES: Number of pregnancies, pregnancy outcome, spacing of pregnancies, sex of offspring, perinatal and neonatal mortality rates. RESULTS: 41% of the women (535) were primiparous; 7 women (0.5%) were grand multiparous (> 6 births). The women had a mean age of 22 years and a mean of 2.3 pregnancies and 1.8 live children. The sex ratio at birth of the index children was 107 boys per 100 girls. The stillbirth rate was 13.5/1000 births, the neonatal mortality rate was 35.3/1000, and the perinatal mortality rate was 42.0/1000. Girls had an excess neonatal mortality (rate ratio 3.42%; 95% confidence interval 1.68 to 6.98; this was most pronounced among girls born to multiparous women with no living sons (rate ratio 15.48 (2.04 to 177.73) v 1.87 (0.63 to 5.58) in multiparous women with at least one son alive). CONCLUSIONS: In this rural part of Tamil Nadu, women had a controlled reproductive pattern. The excess neonatal mortality among girls constitutes about one third of the perinatal mortality rate. It seems to be linked to a preference for sons and should therefore be addressed through a holistic societal approach rather than through specific healthcare measures.  相似文献   

16.
Objective To investigate maternal, perinatal, and neonatal outcomes of pregnancies in women with type 1 diabetes in the Netherlands.Design Nationwide prospective cohort study.Setting All 118 hospitals in the Netherlands.Participants 323 women with type 1 diabetes who became pregnant between 1 April 1999 and 1 April 2000.Main outcome measures Maternal, perinatal, and neonatal outcomes of pregnancy.Results 84% (n = 271) of the pregnancies were planned. Glycaemic control early in pregnancy was good in most women (HbA1c ≤ 7.0% in 75% (n = 212) of the population), and folic acid supplementation was adequate in 70% (n = 226). 314 pregnancies that went beyond 24 weeks'' gestation resulted in 324 infants. The rates of pre-eclampsia (40; 12.7%), preterm delivery (101; 32.2%), caesarean section (139; 44.3%), maternal mortality (2; 0.6%), congenital malformations (29; 8.8%), perinatal mortality (9; 2.8%), and macrosomia (146; 45.1%) were considerably higher than in the general population. Neonatal morbidity (one or more complications) was extremely high (260; 80.2%). The incidence of major congenital malformations was significantly lower in planned pregnancies than in unplanned pregnancies (4.2% (n = 11) v 12.2% (n = 6); relative risk 0.34, 95% confidence interval 0.13 to 0.88).Conclusion Despite a high frequency of planned pregnancies, resulting in overall good glycaemic control (early) in pregnancy and a high rate of adequate use of folic acid, maternal and perinatal complications were still increased in women with type 1 diabetes. Neonatal morbidity, especially hypoglycaemia, was also extremely high. Near optimal maternal glycaemic control (HbA1c ≤ 7.0%) apparently is not good enough.  相似文献   

17.
This study examines secular changes in the influence of maternal age, parity and social class on perinatal mortality in Scotland. Using cross-sectional national data on all Scottish legitimate births the effects of these factors are estimated on the risk of stillbirths, neonatal and perinatal deaths, and the extent to which the current pattern of relative risks in the early 1980s has changed over the past 2 decades is investigated. Social class is used as a crude measure of relative as opposed to absolute differences in socioeconomic conditions which may influence reproductive outcomes. The effects of age, parity and social class are estimated using logistic models. The most parsimonious model adequately describing the data is provided by a main effects model without interactions. Despite changes in reproductive behavior, improved access to maternity services and more effective perinatal care, the influence of maternal age and social class on perinatal mortality remained unchanged between 1960 and 1982. Although the absolute risks of stillbirths and neonatal deaths declined in all maternal age groups, this improvement was not accompained by a significant change in the relative risks traditionally associated with age. Despite no significant changes in the traditional J-shaped association between parity and stillbirths, cross-sectional analysis shows that in the early 1980s the risk of both neonatal and perinatal deaths decreased as parity increased. This finding is consistent with the pattern of risks observed in longitudinal studies and retrospective surveys of reproductive histories. In view of the stability of age, parity and social class effects on the risk of perinatal mortality, little if any of the overall decrease in Scottish stillbirth and neonatal death rates can be attributed to a significant narrowing of relative risks. The results suggest that the attributable risk of high maternal age or low social class on perinatal mortality is negligible. Future improvements in perinatal mortality are thus likely to result from a continuation of the uniform decrease in perinatal mortality for women of all ages, parities and social classes and not from a diminishing of differences in relative risks which are now virtually identical for a large and growing % of women in Scotland.  相似文献   

18.
Support for the theory of ecological speciation requires evidence for ecological divergence between species which directly or indirectly causes reproductive isolation. This study investigates effects of ecological vs. genetic disparity of parental species on the presence of endogenous selection (deformation and mortality rates) and potential sources of exogenous selection (growth rates and hatch timing) on hybrids. Hybrid embryonic development is analysed in a common‐garden full‐sib cross of three species belonging to two different ecotypes within the Coregonus lavaretus species flock in the central Alpine region of Europe. Although hatch timing was similar across the three species, embryonic growth rates and egg sizes differed between ecotypes. This led to a mismatch between embryonic growth rate and egg size in hybrid crosses that reveals epistasis between the maternal and embryonic genomes and transgressive hatch times that were asynchronous with control crosses. A strong constraint of egg size to embryo size at late development was also evident. We argue that this demonstrates potential for coadaptation of a maternal trait (egg size) with offspring growth rate to be an important source of selection against hybridization between ecotypes with different egg sizes. Implications for the measurement and quantification of early life‐history traits affected by this additive relationship, such as hatch day and larval size, are also discussed.  相似文献   

19.
Behavioural thermoregulation is important for the success of cool‐climate lizards, and a basis of the cold‐climate hypothesis for the evolution of viviparity in squamate reptiles. The temperature (Tsel) selected by pregnant females in a thermal gradient is considered to be optimal for embryonic development; however, exposure to Tsel throughout pregnancy has been difficult to estimate in small‐bodied lizards as temperature‐sensitive telemetry is impractical. In addition, the value of maternal thermophily during pregnancy is controversial: some studies have shown elevated Tsel, whereas others have found lowered Tsel or no change during pregnancy. We estimated indirectly the overall exposure to Tsel during the 4–5 months of pregnancy of the cool‐climate, sub‐alpine species Oligosoma maccanni (McCann's skink, 3–6 g) from southern New Zealand. The thermal environment available to skinks was modelled using temperature loggers inside validated copper models in basking and retreat sites. Pregnant skinks were able to achieve mean Tsel (28.9 °C) in the field very infrequently (4–15% of each month during the final 4 months of pregnancy). In field thermoregulatory studies, pregnant females did not bask more frequently and did not show altered field body temperature compared with non‐pregnant adults, suggesting that all skinks (whether pregnant or not) thermoregulate maximally whenever conditions allow. Further research on cool‐climate lizards should address the significance for offspring phenotypes of low and variable exposure to Tsel during pregnancy, as well as the significance of temperatures for embryos in maternal bodies (viviparity) versus nest sites (oviparity) arising from differences in maternal body size. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96 , 541–552.  相似文献   

20.

Objective

To investigate the levels of primary health care services for children and their changes in Zhejiang Province, China from 1998 to 2011.

Methods

The data were drawn from Zhejiang maternal and child health statistics collected under the supervision of the Health Bureau of Zhejiang Province. Primary health care coverage, hospital deliveries, low birth weight, postnatal visits, breastfeeding, underweight, early neonatal (<7 days) mortality, neonatal mortality, infant mortality and under-5 mortality were investigated.

Results

The coverage rates for children under 3 years old and children under 7 years old increased in the last 14 years. The hospital delivery rate was high during the study period, and the overall difference narrowed. There was a significant difference (P<0.001) between the prevalence of low birth weight in 1998 (2.03%) and the prevalence in 2011 (2.71%). The increase in low birth weight was more significant in urban areas than in rural areas. The postnatal visit rate increased from 95.00% to 98.45% with a significant difference (P<0.001). The breastfeeding rate was the highest in 2004 at 74.79% and lowest in 2008 at 53.86%. The prevalence of underweight in children under 5 years old decreased from 1.63% to 0.65%, and the prevalence was higher in rural areas. The early neonatal, neonatal, infant and under-5 mortality rates decreased from 6.66‰, 8.67‰, 11.99‰ and 15.28‰ to 1.69‰, 2.36‰, 3.89‰ and 5.42‰, respectively (P<0.001). The mortality rates in rural areas were slightly higher than those in urban areas each year, and the mortality rates were lower in Ningbo, Wenzhou, and Jiaxing regions and higher in Quzhou and Lishui regions.

Conclusion

Primary health care services for children in Zhejiang Province improved from 1998 to 2011. Continued high rates of low birth weight in urban areas and mortality in rural areas may be addressed with improvements in health awareness and medical technology.  相似文献   

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