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1.
The ability to recognize related cells in a population can confer evolutionary benefits. For example, some bacteria use contact-dependent inhibition proteins to distinguish kin from nonkin. Kinship recognition is taken to a new level in Myxococcus, which uses the dual-purpose TraA protein for kin recognition and outer membrane and lipoprotein exchange. In this issue of the Journal of Bacteriology, Wei et al. (X. Wei, C. N. Vassallo, D. T. Pathak, D. Wall, J. Bacteriol. 196:1807–1814, 2014) show that Tra-dependent exchange can be uncoupled from outer membrane vesicle/tube formation, reported elsewhere to mediate outer membrane exchange.  相似文献   

2.
Seven generations of Ceriodaphnia affinis were kept in water of a household sewer. No animal death was observed in the experiment. In a series of generations, the fertility as well as dimensions of newborn water fleas decreased starting from the third generation. These indices in the subsequent generations changed in parallel with the control line.  相似文献   

3.
ABSTRACT  Rather than strictly local expressions of relatedness, kinship in southern Ethiopia has long been entangled with broad political and economic forces as people negotiate relations with each other, past generations, and the state. Accompanying government reforms in the 1990s, idioms of individualism and choice have circulated in transnational and national neoliberal discourses of development, rights, and economics. People in southern Ethiopia who use ideologies of ascribed social statuses to define local social hierarchies have employed these discourses in reshaping relatedness through an expansive trade association, which is referred to as a family and works through kinship principles of descent and generation. Drawing from recent scholarship on kinship and new reproductive technologies, I argue that, through mobile knowledges in neoliberal contexts, people choose this family and its lineage founder, transforming descent relations and land-based ideologies. These choices represent the workings of neoliberal governmentality in altering cultural relations of power and inequality. [Keywords: kinship, neoliberalism, governmentality, hereditary status groups, Ethiopia]  相似文献   

4.

Objective

The relationship between weight loss and mortality has important clinical and public health significance but has proved to be complex. Evidence is mixed and particularly limited on the association between weight loss in mid-life and premature death (i.e. before 65 years of age), a small albeit important segment of total mortality. We aimed to study the association between midlife weight change and mortality accounting for health and lifestyle characteristics, and also considering potential bias due to preexisting chronic diseases and smoking status.

Design

Longitudinal, population-based, ‘the 1946 British’ birth cohort study.

Subjects and Measures

In 2750 men and women, mortality from age 53 through 65 years was analyzed according to categories of measured 10 year weight change between 43 and 53 years. Cox''s hazard ratios (HR) were progressively adjusted for socio-demographic, lifestyle and health characteristics.

Results

Nearly 20% of participants lost weight and over 50% gained 5 kg or more in midlife. There were 164 deaths. Compared to those who gained between 2 and 5 kg, those who lost 5 kg or more had an increased risk of premature death independently of midlife physical activity, socio-economic circumstances and educational attainment. This association was unaltered when highest weight loss (lost more than 15 Kg) (p = 0.04) and early deaths were excluded (p<0.001), but was no longer significant after adjustment for cardiovascular risk factors and health status (HR = 1.8; 95% CI: 0.9 to 3.5).

Conclusion

The inverse association between weight loss in midlife and higher risk of premature death may be explained by vascular risk factors and ill health. In consideration of the burden of premature death, closer monitoring of weight loss in mid-life is warranted.  相似文献   

5.
6.

Objectives

To evaluate in a national standardised setting whether the performance of ultrasound dating during the first rather than the second trimester of pregnancy had consequences regarding the definition of pre- and post-term birth rates.

Methods

A cohort study of 8,551 singleton pregnancies with spontaneous delivery was performed from 2006 to 2012 at Copenhagen University Hospital, Holbæk, Denmark. We determined the duration of pregnancy calculated by last menstrual period, crown rump length (CRL), biparietal diameter (1st trimester), BPD (2nd trimester), and head circumference and compared mean and median durations, the mean differences, the systematic discrepancies, and the percentages of pre-term and post-term pregnancies in relation to each method. The primary outcomes were post-term and pre-term birth rates defined by different dating methods.

Results

The change from use of second to first trimester measurements for dating was associated with a significant increase in the rate of post-term deliveries from 2.1–2.9% and a significant decrease in the rate of pre-term deliveries from 5.4–4.6% caused by systematic discrepancies. Thereby 25.1% would pass 41 weeks when GA is defined by CRL and 17.3% when BPD (2nd trimester) is used. Calibration for these discrepancies resulted in a lower post-term birth rate, from 3.1–1.4%, when first compared to second trimester dating was used.

Conclusions

Systematic discrepancies were identified when biometric formulas were used to determine duration of pregnancy. This should be corrected in clinical practice to avoid an overestimation of post-term birth and unnecessary inductions when first trimester formulas are used.  相似文献   

7.

Background

The medical needs of older people are growing because the proportion of the older population is increasing and disease boundaries are widening. This study describes the distribution and clustering of 15 common clinical disorders requiring medical treatment or supervision in a representative British cohort approaching retirement, and how health tracked across adulthood.

Methods and Findings

The data come from a cohort of 2661 men and women, 84% of the target sample, followed since birth in England, Scotland and Wales in 1946, and assessed at 60–64 years for: cardio and cerebro-vascular disease, hypertension, raised cholesterol, renal impairment, diabetes, obesity, hypothyroidism, hyperthyroidism, anaemia, respiratory disease, liver disease, psychiatric problems, cancers, atrial fibrillation on ECG and osteoporosis. We calculated the proportions disorder-free, with one or more disorders, and the level of undiagnosed disorders; and how these disorders cluster into latent classes and relate to health assessed at 36 years. Participants had, on average, two disorders (range 0–9); only 15% were disorder-free. The commonest disorders were hypertension (54.3%, 95% CI 51.8%–56.7%), obesity (31.1%, 28.8%–33.5%), raised cholesterol (25.6%, 23.1–28.26%), and diabetes or impaired fasting glucose (25.0%, 22.6–27.5%). A cluster of one in five individuals had a high probability of cardio-metabolic disorders and were twice as likely than others to have been in the poorest health at 36 years. The main limitations are that the native born sample is entirely white, and a combination of clinical assessments and self reports were used.

Conclusions

Most British people reaching retirement already have clinical disorders requiring medical supervision. Widening disease definitions and the move from a disease-based to a risk-based medical model will increase pressure on health services. The promotion of healthy ageing should start earlier in life and consider the individual''s ability to adapt to and self manage changes in health.  相似文献   

8.
Researchers analyzed data from the National Child Development Study--a cohort of every child born in England, Scotland, and Wales during the 1st week of March 1953 with follow up studies in 1965, 1969, 1973, and 1980-1981 to examine the relationship between health status and birth order and whether children with low birth orders were less likely to experience illness than those with older siblings. 1st born children tended to have received the needed number of immunizations, but children of higher birth order did not tend to have received them. Further they were more likely to have attended infant welfare and toddler clinics for health care than children of higher birth order. The only childhood contagious disease which demonstrated a social class effect was pertussis. It tended to afflict children from nonmanual homes regardless of birth order. Absences from school lasting between 1 week-1 month of 1st born children were less frequent than for other children. The leading reasons for 1st, 3rd, and later born 11 year old children who experienced such long absences included infectious diseases; bronchitis; ear, nose, and throat complaints; pneumonia; tonsillitis, or viral influenza. After age 15, 1st and 2nd born children were less likely to be absent and, if absent, they tended to only miss 1 week of school. Significantly more 3rd and 4th born children were absent from school for 1 week-3 months. 1st and 2nd born children from more affluent families tended to have early childhood asthma. In conclusion, the health experiences of the later birth orders were different than those of the 1st born. This did not mean, however, that later birth order children were in poorer health than 1st born children.  相似文献   

9.
Numerous functional features that promote the natural progression of the birth to breastfeeding continuum are concentrated in the human female’s areolar region. The aim of this study was to look more closely into the thermal characteristics of areola, which are said to regulate the local evaporation rate of odors and chemical signals that are uniquely important for the neonate’s ‘breast crawl’. A dermatological study of the areolae and corresponding intern breast quadrants was undertaken on the mothers of 70 consecutive, healthy, full-term breastfed infants. The study took place just after the births at the Policlinico Abano Terme, in Italy from January to February 2014. Temperature, pH and elasticity were assessed one day postpartum using the Soft Plus 5.5 (Callegari S.P.A., Parma, Italy). The mean areolar temperature was found to be significantly higher than the corresponding breast quadrant (34.60 ±1.40°C vs. 34.04 ±2.00°C, p<0.001) and the pH was also significantly higher (4.60±0.59 vs. 4.17±0.59, p<0.001). In contrast, the elasticity of the areolar was significantly lower (23.52±7.83 vs. 29.02±8.44%, p<0.003). Our findings show, for the first time, that the areolar region has a higher temperature than the surrounding breast skin, together with higher pH values and lower elasticity. We believe that the higher temperature of the areolar region may act as a thermal signal to guide the infant directly to the nipple and to the natural progression of the birth to breastfeeding continuum.  相似文献   

10.

Background

Previous studies have found associations between cognitive function and chronic kidney disease. We aimed to explore possible explanations for this association in the Medical Research Council National Survey of Health and Development, a prospective birth cohort representative of the general British population.

Methods

Cognitive function at age 60–64 years was quantified using five measures (verbal memory, letter search speed and accuracy, simple and choice reaction times) and glomerular filtration rate (eGFR) at the same age was estimated using cystatin C. The cross-sectional association between cognitive function and eGFR was adjusted for background confounding factors (socioeconomic position, educational attainment), prior cognition, and potential explanations for any remaining association (smoking, diabetes, hypertension, inflammation, obesity).

Results

Data on all the analysis variables were available for 1306–1320 study members (depending on cognitive measure). Verbal memory and simple and choice reaction times were strongly associated with eGFR. For example, the lowest quartile of verbal memory corresponded to a 4.1 (95% confidence interval 2.0, 6.2) ml/min/1.73 m2 lower eGFR relative to the highest quartile. Some of this association was explained by confounding due to socioeconomic factors, but very little of it by prior cognition. Smoking, diabetes, hypertension, inflammation and obesity explained some but not all of the remaining association.

Conclusions

These analyses support the notion of a shared pathophysiology of impaired cognitive and kidney function at older age, which precedes clinical disease. The implications of these findings for clinical care and research are important and under-recognised, though further confirmatory studies are required.  相似文献   

11.
PurposeTo investigate the associations of time spent sedentary, in moderate-to-vigorous-intensity physical activity (MVPA) and physical activity energy expenditure (PAEE) with physical capability measures at age 60-64 years.MethodsTime spent sedentary and in MVPA and, PAEE were assessed using individually calibrated combined heart rate and movement sensing among 1727 participants from the MRC National Survey of Health and Development in England, Scotland and Wales as part of a detailed clinical assessment undertaken in 2006-2010. Multivariable linear regression models were used to examine the cross-sectional associations between standardised measures of each of these behavioural variables with grip strength, chair rise and timed up-&-go (TUG) speed and standing balance time.ResultsGreater time spent in MVPA was associated with higher levels of physical capability; adjusted mean differences in each capability measure per 1standard deviation increase in MVPA time were: grip strength (0.477 kg, 95% confidence interval (CI): 0.015 to 0.939), chair rise speed (0.429 stands/min, 95% CI: 0.093 to 0.764), standing balance time (0.028 s, 95% CI: 0.003 to 0.053) and TUG speed (0.019 m/s, 95% CI: 0.011 to 0.026). In contrast, time spent sedentary was associated with lower grip strength (-0.540 kg, 95% CI: -1.013 to -0.066) and TUG speed (-0.011 m/s, 95% CI: -0.019 to -0.004). Associations for PAEE were similar to those for MVPA.ConclusionHigher levels of MVPA and overall physical activity (PAEE) are associated with greater levels of physical capability whereas time spent sedentary is associated with lower levels of capability. Future intervention studies in older adults should focus on both the promotion of physical activity and reduction in time spent sedentary.  相似文献   

12.
13.
14.
15.

Background

The influence of asthma candidate genes on the development from wheeze to asthma in young children still needs to be defined.

Objective

To link genetic variants in asthma candidate genes to progression of wheeze to persistent wheeze into childhood asthma.

Materials and Methods

In a prospective study, children with recurrent wheeze from the ADEM (Asthma DEtection and Monitoring) study were followed until the age of six. At that age a classification (transient wheeze or asthma) was based on symptoms, lung function and medication use. In 198 children the relationship between this classification and 30 polymorphisms in 16 asthma candidate genes was assessed by logistic regression. In case of an association based on a p<0.10, replication analysis was performed in an independent birth cohort study (KOALA study, n = 248 included for the present analysis).

Results

In the ADEM study, the minor alleles of ADAM33 rs511898 and rs528557 and the ORMDL3/GSDMB rs7216389 polymorphisms were negatively associated, whereas the minor alleles of IL4 rs2243250 and rs2070874 polymorphisms were positively associated with childhood asthma. When replicated in the KOALA study, ADAM33 rs528557 showed a negative association of the CG/GG-genotype with progression of recurrent wheeze into childhood asthma (0.50 (0.26-0.97) p = 0.04) and no association with preschool wheeze.

Conclusion

Polymorphisms in ADAM33, ORMDL3/GSDMB and IL4 were associated with childhood asthma in a group of children with recurrent wheeze. The replication of the negative association of the CG/GG-genotype of rs528557 ADAM33 with childhood asthma in an independent birth cohort study confirms that a compromised ADAM33 gene may be implicated in the progression of wheeze into childhood asthma.  相似文献   

16.
Kuznetsov  M. B.  Kolobov  A. V. 《Biophysics》2019,64(2):279-292
Biophysics - The effect of chemotherapy on the composition of a solid biclonal tumor was studied using mathematical modeling. In a solid biclonal tumor, cells of one population possess greater...  相似文献   

17.
In a British population cigarette smoking during pregnancy increased the late fetal plus neonatal mortality rate by 28% and reduced birth weight by 170 g, and these differences persist even after allowing for a number of “mediating” maternal and social variables. A change in smoking habit by the end of the fourth month of pregnancy places a mother in the risk category appropriate to her changed habit. This evidence should have important implications for health education aimed at getting pregnant mothers to give up smoking.  相似文献   

18.
Objective: To examine the association between birth weight and cognitive function in the normal population. Design: A longitudinal, population based, birth cohort study. Participants: 3900 males and females born in 1946. Main outcome measures: Cognitive function from childhood to middle life (measured at ages 8, 11, 15, 26, and 43 years). Results: Birth weight was significantly and positively associated with cognitive ability at age 8 (with an estimated standard deviation score of 0.44 (95% confidence interval 0.28 to 0.59)) between the lowest and highest birthweight categories after sex, father's social class, mother's education, and birth order were controlled for. This association was evident across the normal birthweight range (>2.5 kg) and so was not accounted for exclusively by low birth weight. The association was also observed at ages 11, 15, and 26, and weakly at age 43, although these associations were dependent on the association at age 8. Birth weight was also associated with education, with those of higher birth weight more likely to have achieved higher qualifications, and this effect was accounted for partly by cognitive function at age 8. Conclusions: Birth weight was associated with cognitive ability at age 8 in the general population, and in the normal birthweight range. The effect at this age largely explains associations between birth weight and cognitive function at subsequent ages. Similarly, the association between birth weight and education was accounted for partly by earlier cognitive scores.  相似文献   

19.
20.
It has been suggested that human mothers are cooperative breeders, as they need help from others to successfully raise offspring. Studies working under this framework have found correlations between the presence of kin and both child survival and female fertility rates. This study seeks to understand the proximate mechanisms by which kin influence fertility using data from the 1987 Thailand Demographic and Health Survey (DHS), a nationally representative sample of 6775 women. Kin influence is measured by the length of time couples live with the husband's or wife's parents after marriage. Event history analysis, multilevel modeling and structural equation modeling are used to investigate both fertility outcomes and potential pathways through which postnuptial residence may influence fertility outcomes, including employment status, maternal and child outcomes, contraceptive use, breastfeeding duration, and age at marriage. We show that living virilocally (with husband's kin after marriage) increases total fertility by shortening time from marriage to first birth, and increasing the likelihood of progression to each subsequent birth. These effects are mediated through correlations between virilocal residence and earlier age at marriage as well as delayed initiation of contraceptive use. We find no influence of husband's kin on maternal or child outcomes. Living uxorilocally (with wife's kin after marriage) also reduces age at marriage, shortens time from marriage to first birth and (marginally) improves child survivorship, but has no effect on other child and maternal outcomes or progression to subsequent births and results in a similar number of living children as women living neolocally.  相似文献   

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