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61.
62.

Background

Khat chewing has become a highly prevalent practice and a growing public health concern in Ethiopia. Although there have been many small scale studies, very limited national information has been available in the general population. This study aimed to identify factors associated with khat chewing practice among Ethiopian adults.

Methods

The study used the 2011 Ethiopian demographic and health survey data. The survey was cross-sectional by design and used a multistage cluster sampling procedure. Bivariate and multivariable logistic regression models with adjusted odds ratio (AOR) and their 95% confidence intervals (CI) were used to quantify the predictors.

Results

The overall khat chewing prevalence was 15.3% (95% CI: 14.90–15.71). Regional variation was observed with the highest in Harari [(53.2% (95% CI: 43.04–63.28)] and lowest in Tigray regional state [(1.1% (95% CI: 0.72–1.66)]. Multivariable analysis showed that Islam followers were 23.8 times more likely to chew khat as compared to Orthodox followers. Being a resident in Oromiya, South Nation, Nationalities and People (SNNP), Gambella, Harari and Dire Dawa regions had 1.9, 1.6, 3.1, 5.2 and 3.5 times higher odds of chewing khat as compared to Addis Ababa residents, respectively. Adults in the age group 45–49 years were 3.6 times more likely to chew khat as compared to 15–19 years. The middle and richest wealth quintiles were 1.3 and 1.5 times more likely to chew khat, respectively, as compared to the poorest category. Rural residents had 1.3 odds of chewing khat than urban residents. Those individuals who had occupation in sales, agriculture, service sector, skilled and unskilled manual workers were 1.6, 1.3, 2.4, 1.7 and 2.3 times more likely to chew khat, respectively, as compared to those who have no occupation. Females were 77% less likely to chew khat as compared to males. Formerly married and those experienced in child death had 1.4 and 1.2 times higher odds to chew khat as compared with those never married and never had child death, respectively. Those who attended mass media were 1.4 times more likely to chew khat compared with not attended.

Conclusion

Khat chewing is a public health concern in Ethiopia. The highest wealth quintiles, older age group, rural residence, child death, formerly married, males, regions of Oromiya, SNNP, Gambella, Harari and Dire Dawa and Islamic followers had statistically significant association with khat chewing. Due attention needs to be given for these factors in any intervention procedures.  相似文献   
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目的:了解铅锌镉联合染毒对大鼠血液系统的影响及营养干预对其损伤的修复作用。方法:选择SPF级初断乳Wistar大鼠72只,随机分为对照组、染毒组和干预组,分别采用生理盐水、铅锌镉联合染毒液及染毒后以营养干预液灌胃28天和56天之后,检测其血液系统中五元素和血细胞的指标。结果:染毒组较对照组大鼠血铜、血锌含量高,血钙含量低于对照组,差异均有统计学意义(P〈0.05);染毒组血铜含量高于干预组,血钙含量低于干预组,差异均有统计学意义(P〈0.05);干预组红细胞(RBC)计数、血红蛋白(Hb)、血细胞比容(HCT)均高于染毒组,差异均有统计学意义(P〈0.05);对照组白细胞(WBC)计数高于染毒组、干预组,差异均有统计学意义(P〈0.05)。结论:铅镉对大鼠血铜、血钙、血锌水平有影响;综合营养干预对重金属元素造成的血液系统损伤有明显的拮抗作用,对血液系统有一定的保护及修复作用。  相似文献   
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Designing breeding schemes suitable for smallholder livestock production systems in developing regions has hitherto been a challenge. The suggested schemes either do not address farmers' breeding goals (centralized station-based nucleus schemes) or yield slow genetic progress (village-based schemes). A new breeding scheme that integrates the merits of previously suggested schemes has been designed for Menz sheep improvement in Ethiopia. It involves selection based on breeding values in nucleus flocks to produce elite rams, a one-time only provision of improved rams to villagers and a follow-up village-based selection to sustain genetic progress in village flocks. Here, we assessed whether conventional selection of breeding rams based on breeding values for production traits, which is the practice in station-based nucleus flocks, meets farmers' breeding objectives. We also elicited determinants of farmers' ram choice. Low but significant correlations were found between rankings of rams based on farmers' selection criteria, estimated breeding values (EBV) and body weight (BW). Appearance traits (such as color and horn) and meat production traits (BW and linear size traits) significantly determined farmers' breeding ram choice. The results imply that conventional selection criteria based solely on EBV for production traits do not address farmers' trait preferences fully, but only partially. Thus, a two-stage selection procedure involving selection on breeding values in nucleus centers followed by farmers' selection among top- ranking candidate rams is recommended. This approach accommodates farmers' preferences and speeds up genetic progress in village-based selection. The Menz sheep scheme could be applied elsewhere with similar situations to transform conventional station-based nucleus breeding activities into participatory breeding programs.  相似文献   
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Myeloid-derived suppressor cells (MDSC) are a heterogenous population of cells comprising myeloid progenitor cells and immature myeloid cells, which have the ability to suppress the effector immune response. In humans, MDSC have not been well characterized owing to the lack of specific markers, although it is possible to broadly classify the MDSC phenotypes described in the literature as being predominantly granulocytic (expressing markers such as CD15, CD66, CD33) or monocytic (expressing CD14). In this study, we set out to perform a direct comparative analysis across both granulocytic and monocytic MDSC subsets in terms of their frequency, absolute number, and function in the peripheral blood of patients with advanced GI cancer. We also set out to determine the optimal method of sample processing given that this is an additional source of heterogeneity. Our findings demonstrate consistent changes across sample processing methods for monocytic MDSC, suggesting that reliance upon cryopreserved PBMC is acceptable. Although we did not see an increase in the population of granulocytic MDSC, these cells were found to be more suppressive than their monocytic counterparts.  相似文献   
68.
Propagule dispersal in plants is a fundamental mechanism for colonizing new sites and adapting to changing climates, as well as for maintaining genetic diversity. Contrasting past and current gene dispersal can provide useful insights to gauge the extent of recent human disturbances and guide management strategies. However, research on gene dispersal of plants is not yet exhaustive because evolutionary or environmental impacts are often species‐specific and most existing studies have focused on analysis of dispersal at a single site, which may not be helpful for landscape‐level inferences and management interventions. In the present study, we assessed whether current gene or propagule dispersal would be more restricted than past gene dispersal at multiple patches of the endangered medicinal tree, Prunus africana. We employed eight highly polymorphic microsatellite markers in conjunction with isolation‐by‐distance, spatial genetic structure (SGS), and parentage assignment models to estimate gene dispersal distance in a spatial extent of approximately 400 km2. There was no significant difference between gene dispersal distances across the different models (Friedman chi‐squared = 7.286, d.f. = 5, P = 0.2002). Estimates of current gene dispersal distance were comparable to dispersal in the last few generations. However, gene dispersal distance was much shorter in smaller than bigger forest patches. Further, significant (P < 0.05) SGS was detected in most forest patches, with the extent of SGS among adults being stronger in the smaller than bigger patches. These results suggest the need for practicing enrichment plantings in most forest patches, particularly in the smaller ones, to assist gene exchange among individuals and patches. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 887–904.  相似文献   
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Background

In countries where registration of vital events is lacking and the proportion of people who die at home without medical care is high, verbal autopsy is used to determine and estimate causes of death.

Methods

We conducted 723 verbal autopsy interviews of adult (15 years of age and above) deaths from September 2009 to January 2013. Trained physicians interpreted the collected verbal autopsy data, and assigned causes of death according to the international classification of diseases (ICD-10). We did analysis of specific as well as broad causes of death (i.e. non-communicable diseases, communicable diseases and external causes of death) by sex and age using Stata version 11.1. We performed logistic regression to identify socio-demographic predictors using odds ratio with 95% confidence interval and a p-value of 0.05.

Findings

Tuberculosis, cerebrovascular diseases and accidental falls were leading specific causes of death accounting for 15.9%, 7.3% and 3.9% of all deaths. Two hundred sixty three (36.4% [95% CI: 32.9, 39.9]), 252 (34.9% [95% CI: 31.4, 38.4]) and 89 (12.3% [95% CI: 10.1, 14.9]) deaths were due to non-communicable, communicable diseases, and external causes, respectively. Females had 1.5 times (AOR = 1.53 [95% CI: 1.10, 2.15]) higher odds of dying due to communicable diseases than males. The odds of dying due to external causes were 4 times higher among 15–49 years of age (AOR = 4.02 [95% CI: 2.25, 7.18]) compared to older ages. Males also had 1.7 times (AOR = 1.70 [95% CI: 1.01, 2.85]) higher odds of dying due to external causes than females.

Conclusion

Tuberculosis, cerebrovascular diseases and accidental falls were the top three causes of death among adults. Efforts to prevent tuberculosis and cerebrovascular diseases related deaths should be improved and safety efforts to reduce accidents should also receive attention.  相似文献   
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