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1.
Retrospective estimates of nightmare frequency for a sample of 23,990 respondents to an Internet questionnaire (female: N = 19,367, mean age = 24.9 ± 10.14 years; male: N = 4,623; mean age = 25.5 ± 10.81) were evaluated as a function of age, gender, and pre- versus post-September 11, 2001. Female respondents reported more frequent monthly nightmares (4.44 ± 6.71) than did male respondents (3.39 ± 6.07), and this result was seen for all age strata younger than 60. Also, for female respondents, nightmare frequency increased from ages 10-19 to 20-39 then decreased monotonically to ages 50-59. For male respondents, nightmare frequency was stable from ages 10-19 to 30-39 then decreased to ages 50-59. An increase in nightmare frequency was observed post-September 11 only for male respondents-particularly for 10- to 29-year-olds. This increase was sustained 2 years later. These effects were maintained when dream recall was held constant. Results replicate, in a single sample, previously published gender and age effects and provide new evidence that the nightmares of males may be differentially sensitive to traumatic events for which victims and/or perpetrators are primarily male. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
A. Singh 《CMAJ》1975,113(8):733-735
Of 108 patients with familial hyperlipoproteinemia between the ages of 22 and 85 years (mean, 55.1 years) 46 (42.6%) had cholelithiasis. Among the 53 patients with type II hyperlipoproteinemia 20 (38%) had gallstones; the male:female ratio was 1:2; the mean serum triglyceride value was significantly higher in those with gallstones. Among the 50 patients with type IV hyperlipoproteinemia 25 (50%) had gallstones; the male:female ratio was 1:1; the mean age was significantly higher in those with gallstones. Among the five patients with type V hyperlipoproteinemia one had gallstones. Electrocardiographic evidence of myocardial damage was present in 47 (44%) of the 108 patients; 18 (39%) of the 46 patients with gallstones showed such abnormalities, while 26 (24%) showed sinus bradycardia.  相似文献   

3.
There is little information about the age at which the ischiopubic ramus fuses derived from dry bone observations. This study documents the age ranges for union of the ischiopubic ramus in a sample of 148 known sex and age skeletons from Portugal, with ages ranging from birth to 20 years, using a three-stage scheme. The oldest female with an unfused ramus is 11 years old and the oldest male is 8 years old. The youngest male with a completely fused ramus is 7 years old, and the youngest female is 5 years old. Despite the relatively large sample size, partial fusion was a rare event to record as only two individuals were at this stage and these seemed relatively older than expected (12 and 14 years of age). The likely age interval for partial union of the ramus was subsequently estimated from logistic regression, for both sexes separated and combined. In the sex-pooled sample, the inter-quartile range (25th–75th percentile) for the median age of fusion is 7–11 years and the 10th–90th percentile range is 4–15 years. The scarcity of data on the age of ischiopubic fusion may be related to biases in the sample or to fusion occurring rapidly in this anatomical location. Additional studies may be required to assess the accuracy of the ages reported here, but at present this study provides the most comprehensive assessment of timing of fusion at the ischiopubic ramus from observations of dry bone specimens.  相似文献   

4.
We examined evidence for developmental and generational differences in dreaming in color from childhood to old age. To separate these effects, we surveyed the frequency of color experience in dreams twice, with a 16-year interval between surveys. In the 1993 survey, 2,077 (male: 1,194; female: 883; ages: 10 to 85 years) and, in 2009, 1,328 (male: 596; female: 732; ages: 11 to 89 years) participants completed a dream recall questionnaire that included a question about the presence of color in their dreams. In both surveys, approximately 80% of subjects younger than 30 years of age experienced color in their dreams, but the percentage decreased with age and fell to approximately 20% by the age of 60. The frequency of dreaming in color increased from 1993 to 2009 only for respondents in their 20s, 30s, and 40s. We speculate that color TV may play a role in the generational difference observed. However, it is true that generation affects the incidence of color in dreams, as suggested by Schwitzgebel, Huang, and Zhou (2006) and Murzyn (2008), although this effect is very small compared with that of aging. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

5.
The data of this study, an extension of a previous study on secondary sex ratio in the human population of Muridke, Punjab, Pakistan, are based on the population of Muridke, 27 km north of Lahore, Punjab, Pakistan. Records of deaths of children, at later stages of birth, for different birth ranks, and that of maternal and paternal ages were made. 1000 families were scored for this study. Families providing the required information were included. Data for paternal age and maternal age combination consisted of 4807 total number of children of which 2586 were male. Paternal age and birth order combination was comprised of a total of 4405 children, containing 2316 males. Maternal age and birth order combination consisted of 4658 children, of which 2458 were males. The discrepancy in the number of children in the 3 types of combinations was due to the lack of required information in different groups. Sex ratio based on total number of males in relation to paternal age and maternal age was 0.54. Younger fathers (15-19 years) showed higher sex ratio (0.69). This dropped in paternal age groups 20-24 years (0.59) and 25-29 years (0.51). Younger mothers (15-19 years) showed higher sex ratio (0.62), declines in the age groups 20-24 years (0.52) and 25-29 years (0.51) and rise in age groups 35-39 years (0.55) and 40-44 years (0.54). Chi-square tests were carried out to compare the number of male and female offspring in the paternal age groups 15-19, 20-24, and 25-29 years. These showed highly significant deviation from the expected number. The higher age groups showed nonsignificant differences in the number of male and female offspring. Maternal age groups 15-19, 20-24, and 25-29 years showed highly significant differences in the male and female offspring and nonsignificant results in the higher age groups. Maternal age in relation to paternal age showed positive simple and partial correlations. Sex ratio for the total number of males based on paternal age and birth order was 0.52. 1st birth order showed higher sex ratio (0.55) and decreased in the 2nd (0.50) and 3rd birth orders (0.51), showed increase in the 4th birth order (0.53) and declines in the higher birth ranks. The number of male and female offspring in the birth orders 1, 2, and 3 showed significant differences, but in higher birth ranks the difference was insignificant. Paternal age and birth order indicated positive simple and partial correlations. Higher sex ratio (0.58) was seen in the 1st birth order and then it decreased in the 2nd (0.50) and 3rd (0.51) birth order. Chi-square tests carried out to compare the number of male and female offspring in borth orders 1, 2, and 3 showed highly significant differences but in higher birth ranks the difference was insignificant.  相似文献   

6.
Five mass strandings of Pilot whales, involving from 23 to 40 animals, occurred on the British coast between 1982 and 1985. The sex ratio in all strandings was biased towards females (62% overall), but more than one mature male was present in each group. A multi-male, polygynous social system is suggested. Growth is rapid from a mean body length at birth of 1.78 m to about 3 m at 2–3 years. Thereafter, males grow faster than females and attain a greater body length by some 18–25%. Maximum body lengths in this study were of a 6.3 m male and a 5.5 m female. The greatest ages determined were of a 20-year-old male and a 25-year-old female, but there is a possibility that readable dentine is not deposited in the teeth of older animals and that some whales are thus of a greater age than can be detected. Females become sexually mature at about seven years of age and a body length of 3–4 m. Some reach sexual senility before death. Males mature at a greater age and at about 5 m in length. Annual calf production is about 11% and no seasonality in parturition could be detected. Pollutant levels are generally within the range of those published for odontocetes, but PCB levels are higher than any yet found in other Pilot whale populations. Evidence of squid was found in three digestive tracts. Blubber thickness increases with the size of the animal, reaching 35–65 mm in adults. The existence of an annual, rigid north-south migrational pattern is unlikely.  相似文献   

7.
<正>普通斑马又称平原斑马(Equus burchelli),隶属于奇蹄目马科,是一种极具观赏价值的大型哺乳动物。广泛分布于非洲,喜欢栖息在平原和草原,随季节和食物迁徙。普通斑马是社会性动物,习惯群体生活,规模较小的群体由1只雄性和2-6只雌性以及它们未成年的子女组成;或是由十几只未成年的雄性普通斑马组成;较大的群体则有几百只,它们通常是由若干个小规模的群体组成。雄性  相似文献   

8.
Intergenerational effects arise when parents' actions influence the reproduction and survival of their offspring and possibly later descendants. Models suggest that intergenerational effects have important implications for both population dynamical patterns and the evolution of life-history traits. However, these will depend on the nature and duration of intergenerational effects. Here we show that manipulating parental food environments of soil mites produced intergenerational effects that were still detectable in the life histories of descendents three generations later. Intergenerational effects varied in different environments and from one generation to the next. In low-food environments, variation in egg size altered a trade-off between age and size at maturity and had little effect on the size of eggs produced in subsequent generations. Consequently, intergenerational effects decreased over time. In contrast, in high-food environments, variation in egg size predominantly influenced a trade-off between fecundity and adult survival and generated increasing variation in egg size. As a result, the persistence and significance of intergenerational effects varied between high- and low-food environments. Context-dependent intergenerational effects can therefore have complex but important effects on population dynamics.  相似文献   

9.
To assess the potential application of pteridine fluorescence in determining the age of adult Boettcherisca peregrina (Diptera: Sarcophagidae) Robineau‐Desvoidy and further for the postmortem interval, the age‐dependent changes of pteridine fluorescence were investigated for the adults maintained at five constant temperatures. From the results, significant linear relationships were found between pteridine fluorescence and the age of the adults maintained at 16, 20, 24, 28 or 32 °C (P < 0.001, r2 > 0.85). In addition, the relationships between the rate of pteridine accumulation and temperature were well described using linear equations for adult females and males. Then for each cohort of the flies at the ambient temperature, a calendar was constructed and used to determine the ages of females and males, respectively, in which was recorded in reverse time order the amount of pteridine accumulated per hour by the flies and their expected pteridine level when they emerged at the specified time. A significant linear relationship between estimated ages and chronological ages was observed for female or male adults, with the mean errors of the estimated ages of ±1.82 days for females and ±1.58 days for males. It is suggested that pteridine fluorescence analysis has a potential value in determining the age of adult B. peregrina.  相似文献   

10.
Because the determinants of anxiety and depression in late adolescence and early adulthood may differ from those in later life, we investigated the temporal stability and magnitude of genetic and environmental correlates of symptoms of anxiety and depression across the life span. Data were collected from a population-based Australian sample of 4364 complete twin pairs and 777 singletons aged 20 to 96 years who were followed-up over three studies between 1980 and 1996. Each study contained the 14-item self-report DSSI/sAD scale which was used to measure recently experienced symptoms of anxiety and depression. Symptom scores were then divided and assigned to age intervals according to each subject's age at time of participation. We fitted genetic simplex models to take into account the longitudinal nature of the data. For male anxiety and depression, the best fitting simplex models comprised a single genetic innovation at age 20 which was transmitted, and explained genetic variation in anxiety and depression at ages 30, 40, 50 and 60. Most of the lifetime genetic variation in female anxiety and depression could also be explained by innovations at age 20 which were transmitted to all other ages; however, there were also smaller age-dependent genetic innovations at 30 for anxiety and at 40 and 70 for depression. Although the genetic determinants of anxiety and depression appear relatively stable across the lifespan for males and females, there is some evidence to support additional mid-life and late age gene action in females for depression. The fact that midlife onset for anxiety occurs one decade before depression is also consistent with a causal relationship (anxiety leading to depression) between these conditions. These findings have significance for large scale depression prevention projects.  相似文献   

11.
The aim of this study was to evaluate changes in heart rate (HR), QT and RR intervals and corrected QT (QTc) values in conscious male and female New Zealand rabbits which intravenously received oxytocin (OXT) at different dosages. Animals were divided into 6 equal groups: group I (n = 6 male, received 0.75 U OXT per animal); group II (n = 6 male, received 1.5 U OXT per animal); group III (n = 6 male, received 3 U OXT per animal); group IV (n = 6 female, received 0.75 U OXT per animal); group V (n = 6 female, received 1.5 U OXT per animal); group VI (n = 6 female, received 3 U OXT per animal). ECG recording were taken from all animals before injection and then at 2, 4, 6, 8, 10, 15 and 20 min of OXT administration. QT and RR intervals obtained at 2 min of OXT administration were significantly prolonged in all groups (p < 0.05) with one exception that is the 1.5 U OXT injected female group where only QT interval did not change. The prolongation of QT and RR intervals persisted for 20 min in 1.5 U OXT injected male group while only QT interval prolongation was obvious for 20 min in 3 U OXT injected female group as for the other groups the prolonged interval were observed for 8-10 min and then returned to baseline values. Generally, a significant prolongation of QTc was noticed in both male and female rabbits at the 2 and 4 min in all groups and bradycardia was noticed at 2 min of OXT administration in all groups. Heart beats returned to normal values in all groups after 8 min of OXT administration. The change of HR, RR, QT and QTc was gender- but not dose-dependent (p < 0.001). The male rabbits were more sensitive to OXT effect then female rabbits. In conclusion, OXT used in therapeutic dosages decreased heart rate and prolonged QT and QTc intervals. Although cardiovascular effect of OXT are of short duration, its use in patient with risk factors for malignant arrhythmias requires more attention.  相似文献   

12.
四川梅花鹿生命表和种群增长率的研究   总被引:4,自引:2,他引:2  
郭延蜀  郑慧珍 《兽类学报》2005,25(2):150-155
1987年、1989—1991年四川梅花鹿产仔期,在四川省若尔盖县铁布自然保护区用耳缺法连续标记了111只(♂♂56,♀♀55)3~10日龄的四川梅花鹿幼仔,根据野外对这批标记仔鹿生长、繁殖、死亡的观察数据编绘出四川梅花鹿的生命表、存活曲线、死亡曲线、种群自然增长率和繁殖价。这批标记仔鹿中,雄鹿和雌鹿的最大寿命分别为14岁和15岁;初生仔鹿的雌雄性比为1:1,5~6岁时雌雄性比为3:1;雌鹿最早的产仔年龄为3~4岁,最晚产仔年龄为11~12岁;雄鹿最早在4~5岁时拥有雌鹿,10—11岁以后就都失去了曾占有的雌鹿群。雄鹿2 3岁时期望寿命最大为5.111,雌鹿1~2岁时期望寿命最大为6.148。雌鹿的存活曲线接近于Odum有关存活曲线的A型,雄鹿的存活曲线属B型。净生殖率、种群自然增长率和平均世代时间分别为1.228、0.031和7.015。雌鹿3—4岁时的繁殖价最高。  相似文献   

13.
Maternal ages at the first maternity (starting), at the last maternity (stopping) and the lengths of intervals between maternities (spacing) have been studied in the Outer Hebridean islands of Harris and Barra for births between the years of 1855 and 1990, a period during which a considerable 'fertility transition' occurred. There was a tendency in each island for increases with time in the ages at starting among less-fecund women (although after 1936 starting ages declined), and highly significant heterogeneity of covariance: adjusted means dependent on the total numbers of maternities experienced. The same result was seen for the ages at stopping. Lengths of reproductive life (the difference between ages at starting and stopping) rose to 1876-1895, and then fell, apart from a short-lived rise in Barra during 1956-1975, possibly due to the papal encyclical Humaneae Vitae. Intervals between marriage and first maternity and between successive maternities were studied by hazard function survival analysis. The marriage first birth interval remained very constant, unaffected by total maternities. The father's occupation and the mother's age at first maternity showed no significant relationships. In Barra there was a weak negative relationship with the date of the marriage. For intervals between maternities in both islands, total maternities and the death of a previous infant were associated with shorter, and birth order with longer intervals. In Harris, there were tendencies for intervals to be consistently long or short in families, and for the age of the mother and date at first maternity to be negatively related to the length of the interval. In Barra, a previous multiple birth was followed by a longer interval. The date of the previous maternity, father's occupation, maternal age at the previous maternity, the sex of the previous child, and the duration of the marriage appeared to have no influence on maternity intervals. Evidence for an effect of economic deprivation during the 19th century on the variables considered was equivocal. During the 20th century, it is suggested that economic depression during the inter-war years, the spread of contraception, and improvements in health care may have acted 'synergistically' to produce the lower ages of childbearing and the shortening of maternity intervals and reproductive lives.  相似文献   

14.
Background A method for assessing dental maturity in different populations was first developed in 1973 by Demirjian and has been widely used and accepted since then. While the accuracy for evaluating dental age using Demirjian’s method compared to children’s chronological age has been extensively studied in recent years, the results currently available remain controversial and ambiguous. Methods A literature search of PubMed, Embase, Web of Science, CNKI and CBM databases was conducted to identify all eligible studies published before July 12th, 2013. Weighted mean difference (WMD) with corresponding 95% confidence interval (95% CI) was used to evaluate the applicability of Demirjian’s method for estimating chronological age in children. Results: A meta-analysis was conducted on 26 studies with a total of 11,499 children (5,301 boys and 6,198 girls) aged 3.5 to 16.9 years. Overall, we found that Demirjian’s method overestimated dental age by 0.35 (4.2 months) and 0.39 (4.68 months) years in males and females, respectively. A subgroup analysis by age revealed that boys and girls between the ages of 5 to 14 were given a dental age estimate that was significantly more advanced than their chronological age. Differences between underestimated dental ages and actual chronological ages were lower for male and female 15- and 16-year-old subgroups, though a significant difference was found in the 16-year-old subgroup. Conclusions Demirjian’s method’s overestimation of actual chronological tooth age reveals the need for population-specific standards to better estimate the rate of human dental maturation.  相似文献   

15.
Boron (B) levels were determined in the serum of 980 healthy inhabitants living in an urban area of Japan by means of inductively coupled plasma emission spectrometry (ICPES). The results showed a log-normal distribution of serum B for both sexes, although there are age-related differences. In male subjects, serum B increases rapidly up to 49 yr of age, reaching a plateau between ages 50 and 69 yr old, followed by a gradual increase up to 70 yr or older. Female subjects exhibit a gradual increase up to the age of 70 yr old. The reference value for male and female subjects was 79.8 μg/L and 67.9 μg/L, and the reference interval was 33.3–191.2 μg/L and 29.5–154.9 μg/L, respectively. The obtained reference value and interval of the nonexposed group may be useful for health screening for B exposure, either for people living in regions with high levels of B in the environment, or for workers who are exposed to this element.  相似文献   

16.
中国高老龄人口两性年龄别生存率及其差异变化   总被引:2,自引:1,他引:1  
本文选用我国4次全国人口普查资料中分年龄性别人口构成的原始数据经移动平均修匀后分析了两性高龄各年龄队列人口在相邻普查期间的生存率及其差异随龄变化,以及每次普查人口高老龄组年龄别性别比。结果表明,两性生存率随龄迅速下降的趋势进入90岁以后的高老龄组将变平甚或上升;老年组男性年龄别生存率始终低于女性的现象在进入90岁以后的高老龄组差异迅速缩小并转而反向扩大。结果预示,尽管男性平均期望寿命低于女性,但并  相似文献   

17.
On the basis on 6 years of observation, we estimated the reproductive parameters of a Golden snub-nosed monkey (Rhinopithecus roxellana) group in the Qinling Mountains, China. We observed 88 births in 47 females from 2001 to 2006. Two methods were used to calculate the birthrate. The first method is based on the number of births observed in a year, giving 0.49+/-0.07 (mean+/-SD), and the second method is based on the female-years of observation, giving 0.49+/-0.17 births per female per year in this troop. The mean interbirth interval is 21.88+/-6.01 months (mean+/-SD). The mortality of infant born between 2002 and 2005 was 22.4%. The interbirth intervals of females that had lost an infant before the age of 6 months were significantly shorter than that of females whose infants survived for more than 6 months. A female usually gives birth once every 2 years if the previous offspring survives to a weaning age of 5-6 months, or will give birth in the next year if the previous young dies before reaching an age of 6 months. Births were significantly concentrated during March to May of each year. The mean birth date was on April 14, median was April 12; and the standard deviation was 13.98 days. Birth peak occurs 6-7 months after mating peak. From observations on 15 individuals that gave birth for the first time, we concluded that the wild female Golden snub-nosed monkeys in Qinling Mountains start giving birth at an age of 5 or 6 years. We suggest that the seasonal reproductive pattern is an adaptive response to the availability of seasonal food. Our results are consistent with the hypothesis that these reproductive characteristics are a result of adaptation to the seasonality of mountain climate and food resources.  相似文献   

18.
The original demographic estimates for Pecos Pueblo, New Mexico (Hooton, 1930) indicated a 60/40 male/female adult sex ratio and an average life expectancy at birth of 42.9 years. A reanalysis of sexes and ages for a subsample of the Pecos collection as well as a reevaluation of a more recent report suggests that the adult sex ratio for Pecos is probably closer to 50/50 and that the mean age at death should be greatly reduced, perhaps by as much as 15 to 20 years.  相似文献   

19.
Summary Hemoglobins M and unstable hemoglobins cause clinical syndromes that are transmitted in autosomal dominant fashion. Pedigrees of 50 probands with de novo mutations producing unstable Hb disease or Hb M disease were compiled. Cases were ascertained (1) by screening the relevant literature published from 1950 through 1980 and (2) through personal communication. Additional pedigree data on several published cases were collected, and a depository containing all available information rekated to de novo Hb mutants was established. The 50 probands were born in 14 countries between 1922 and 1976. Paternity was tested in 36% of the cases, and no instance of false paternity was noted.The data were used to test for an association of advanced parental age with the appearance of de novo mutants. Paternal ages at the probands' births ranged from 20 to 50 years, with a mean of 32.7 years. Maternal ages ranged from 18 to 43 years, with a mean of 28.5 years. For each year and country (or, where necessary, for the nearest possible year and/or a demographically similar country), the cumulative frequency distributions of the ages of parents who had a child in that country and year were computed; the ages of each proband's father and mother were then expressed as percentiles on these distributions. The distribution of paternal age percentiles was shifted toward the upper end of the range, with 11 of the 50 paternal ages falling between the 90th and 100th percentiles. The distribution of maternal age percentiles was more complex, with one peak (10 of 50 ages) falling between the 30th and 40th percentiles and a second peak (10 of 50 ages), between the 90th and 100th percentiles. These distributions, though suggestive of an association of advanced parental age and the appearance of de novo mutations that cause unstable Hb disease or methemoglobinemic cyanosis, were not significantly different from those uniform distributions expected in the absence of a parental age effect.  相似文献   

20.
The purpose of this study was to compare 4 interval training (IT) sessions with different intensities and durations of exercise to determine the effect on mean VO?, total VO?, and duration of exertion ≥95% maximum power output (MPO), and the effects on biomarkers of fatigue such as blood-lactate concentration (BLC) and rating of perceived exertion. The subjects were 12 recreationally competitive male (n = 7, mean ± SD age = 26.2 ± 3.9 years) and female (n = 5, mean ± SD age = 27.6 ± 4.3 years) triathletes. These subjects performed 4 IT sessions on a cycle ergometer varying in intensity (90 and 100% MPO) and duration of exercise (30 seconds and 3 minutes). This study revealed that IT using 30-second duration intervals (30-30 seconds) allows the athlete to perform a longer session, with a higher total and mean VO? HR and lower BLC than 3-minute durations. Similarly, submaximal exertion at 90% of MPO also allows performing longer sessions with a higher total VO? than 100% intensity. Thus, the results of the present study suggested that to increase the total time at high intensity of exercise and total VO? of a single exercise session performed by the athlete, IT protocols of short durations (i.e., 30 seconds) and submaximal intensities (i.e., 90% MPO) should be selected. Furthermore, performing short-duration intervals may allow the athlete to complete a longer IT session with greater metabolic demands (VO?) and lower BLC than longer (i.e., 3 minutes) intervals.  相似文献   

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