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33.

Objectives

Post-abortion contraceptive service is pivotal for the prevention of unwanted pregnancy and alleviation of its complication. Worldwide half of the pregnancy is unplanned, whereas unwanted pregnancy ends up with abortion. This study assessed post-abortion contraceptive uptake and associated factors among abortion service users at health institution in Shire town, North Ethiopia. Institutional based cross-sectional study was conducted from December 15/2016 to March 15, 2017, in Shire town. Data were collected using systematic random sampling technique. Bivariate and multivariable analyses were done to determine the association of each independent variable with the dependent variable.

Results

Overall post-abortion contraceptive utilization in this study was 61.5%. Married [AOR 2.59, 95% CI (1.16, 5.65)], completed College education [AOR 5.69, 95% CI (1.61, 20.11)], previous contraceptive used [AOR 3.62, 95% CI (1.77, 7.40)], counseling of family planning [AOR 3.53 95% CI (1.69, 7.37)], grand multipara [AOR 7.91, 95% CI (1.66, 37.74)] and public health institution [AOR 5.95, 95% CI (3.03, 11.72)] were significantly associated with the post-abortion contraceptive utilization. In this study, post-abortion contraceptive utilization was about two-third. Being married, had been completing a college education, had been receiving family planning counseling, previous contraceptive usage, abortion care service at public health institution, and being grand multiparty were determinants of post-abortion contraceptive utilization.
  相似文献   
34.
The inactivation of one X chromosome in females is normally random with regard to which X is inactivated. However, exclusive or almost-exclusive inactivation of one X may be observed in association with some X-autosomal rearrangements, mutations of the XIST gene, certain X-linked diseases, and MZ twinning. In the present study, a methylation difference near a polymorphism in the X-linked androgen-receptor gene was used to investigate the possibility that nonrandom X inactivation is increases in fetuses and newborns that are associated with confined placental mosaicism (CPM) involving an autosomal trisomy. Extreme skewing was observed in 7 (58%) of 12 cases with a meiotic origin of the trisomy, but in none of 10 cases examined with a somatic origin of the trisomy, and in only 1 (4%) of 27 control adult females. In addition, an extremely skewed X-inactivation pattern was observed in 3 of 10 informative cases of female uniparental disomy (UPD) of chromosome 15. This may reflect the fact that a proportion of UPD cases arise by "rescue" of a chromosomally abnormal conceptus and are therefore associated with CPM. A skewed pattern of X inactivation in CPM cases is hypothesized to result from a reduction in the size of the early-embryonic cell pool, because of either poor early growth or subsequent selection against the trisomic cells. Since approximately 2% of pregnancies detected by chorionic villus sampling are associated with CPM, this is likely a significant contributor to both skewed X inactivation observed in the newborn population and the expression of recessive X-linked diseases in females.  相似文献   
35.
Alternans, a condition in which there is a beat-to-beat alternation in the electromechanical response of a periodically stimulated cardiac cell, has been linked to the genesis of life-threatening ventricular arrhythmias. Optical mapping of membrane voltage (Vm) and intracellular calcium (Cai) on the surface of animal hearts reveals complex spatial patterns of alternans. In particular, spatially discordant alternans has been observed in which regions with a large-small-large action potential duration (APD) alternate out-of-phase adjacent to regions of small-large-small APD. However, the underlying mechanisms that lead to the initiation of discordant alternans and govern its spatiotemporal properties are not well understood. Using mathematical modeling, we show that dynamic changes in the spatial distribution of discordant alternans can be used to pinpoint the underlying mechanisms. Optical mapping of Vm and Cai in paced rabbit hearts revealed that spatially discordant alternans induced by rapid pacing exhibits properties consistent with a purely dynamical mechanism as shown in theoretical studies. Our results support the viewpoint that spatially discordant alternans in the heart can be formed via a dynamical pattern formation process which does not require tissue heterogeneity.  相似文献   
36.
Using data from a cross-sectional nutrition survey conducted in rural Ethiopia between March and April 1992, roughly a year after the end of one of the longest civil wars in modern human history, this study attempts to document the magnitude and correlates of childhood undernutrition in Ethiopia. Findings from the study reveal that, at the time of the survey, 59% of children in the country were exposed to long-term or chronic undernutrition (stunted); about 4% were suffering from acute problems (wasted); and about the same proportion were both stunted and wasted. Less than a third of the country's children had normal growth. The logistic-binomial regression results demonstrated the existence of significant clustering of risks of undernutrition within areas of residence and notable differentials by age of child, duration of breast-feeding, age at introduction of supplementary foods and number of under-five siblings. Significant variations were also noted by age of household head, per capita land holding, religious affiliation and prevalence of endemic diseases in an area.  相似文献   
37.
Using the body mass estimates of 12 long-distance migrating Palearctic passerine species monitored at successive sites across the Eastern Africa flyway, we tested whether birds modulate their body mass according to specific seasonal demands across different geographic sectors. We compared body mass estimates across latitudinal distances and geographic sectors in Europe, the desert, Northeast Africa and East Africa. Our results show that, depending on the species and season considered, the average body mass increase or decrease is variable at and among different geographic sectors. By comparing the variation in body mass between different ecological sectors, we were able to show when and where migrants accumulate their migratory fuel reserves during migration.  相似文献   
38.

Background

Notch receptors are normally cleaved during maturation by a furin-like protease at an extracellular site termed S1, creating a heterodimer of non-covalently associated subunits. The S1 site lies within a key negative regulatory region (NRR) of the receptor, which contains three highly conserved Lin12/Notch repeats and a heterodimerization domain (HD) that interact to prevent premature signaling in the absence of ligands. Because the role of S1 cleavage in Notch signaling remains unresolved, we investigated the effect of S1 cleavage on the structure, surface trafficking and ligand-mediated activation of human Notch1 and Notch2, as well as on ligand-independent activation of Notch1 by mutations found in human leukemia.

Principal Findings

The X-ray structure of the Notch1 NRR after furin cleavage shows little change when compared with that of an engineered Notch1 NRR lacking the S1-cleavage loop. Likewise, NMR studies of the Notch2 HD domain show that the loop containing the S1 site can be removed or cleaved without causing a substantial change in its structure. However, Notch1 and Notch2 receptors engineered to resist S1 cleavage exhibit unexpected differences in surface delivery and signaling competence: S1-resistant Notch1 receptors exhibit decreased, but detectable, surface expression and ligand-mediated receptor activation, whereas S1-resistant Notch2 receptors are fully competent for cell surface delivery and for activation by ligands. Variable dependence on S1 cleavage also extends to T-ALL-associated NRR mutations, as common class 1 mutations display variable decrements in ligand-independent activation when introduced into furin-resistant receptors, whereas a class 2 mutation exhibits increased signaling activity.

Conclusions/Significance

S1 cleavage has distinct effects on the surface expression of Notch1 and Notch2, but is not generally required for physiologic or pathophysiologic activation of Notch proteins. These findings are consistent with models for receptor activation in which ligand-binding or T-ALL-associated mutations lead to conformational changes of the NRR that permit metalloprotease cleavage.  相似文献   
39.
Exposure of roots to low Cd concentration induced morphogenic responses including the inhibition of root growth and the radial swelling of root tip. High Cd concentrations within a few minutes caused a robust induction of superoxide generation leading to the cell death and root growth arrest. This toxic superoxide generation blocked the development of low Cd concentration-activated morphogenic responses. While the morphogenic responses of roots to low Cd concentration are induced very rapidly and probably due to the interaction of Cd with the apoplast of root tissue, high Cd concentration-induced superoxide production required the entry of Cd into the symplast. Auxin signaling is involved in the activation of Cd-induced morphogenic defence responses but not in the Cd-induced toxic superoxide generation. These results suggest that oxidative stress is not a primary cause for the Cd-induced morphogenic responses such as growth reduction and radial cell expansion in barley root tips.  相似文献   
40.
A series of substituted N-(3,5-dichlorobenzenesulfonyl)-(L)-prolyl- and (L)-azetidyl-beta-biaryl beta-alanine derivatives was prepared as selective and potent VLA-4 antagonists. The 2,6-dioxygenated biaryl substitution pattern is important for optimizing potency. Oral bioavailability was variable and may be a result of binding to circulating plasma proteins.  相似文献   
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