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101.

Background

Girl education is believed to be the best means of reducing girl child marriage (marriage <18 years) globally. However, in South Asia, where the majority of girl child marriages occur, substantial improvements in girl education have not corresponded to equivalent reductions in child marriage. This study examines the levels of education associated with female age at marriage over the previous 20 years across four South Asian nations with high rates (>20%) of girl child marriage- Bangladesh, India, Nepal and Pakistan.

Methods

Cross-sectional time series analyses were conducted on Demographic and Health Surveys (DHS) from 1991 to 2011 in the four focal nations. Analyses were restricted to ever-married women aged 20–24 years. Multinomial logistic regression models were used to assess the effect of highest level of education received (none, primary, secondary or higher) on age at marriage (<14, 14–15, 16–17, 18 and older).

Results

In Bangladesh and Pakistan, primary education was not protective against girl child marriage; in Nepal, it was protective against marriage at <14 years (AOR = 0.42) but not for older adolescents. Secondary education was protective across minor age at marriage categories in Bangladesh (<14 years AOR = 0.10; 14–15 years AOR = .25; 16–17 years AOR = 0.64) and Nepal (<14 years AOR = 0.21; 14–15 years AOR = 0.25; 16–17 years AOR = 0.57), but protective against marriage of only younger adolescents in Pakistan (<14 years AOR = 0.19; 14–15 years AOR = 0.23). In India, primary and secondary education were respectively protective across all age at marriage categories (<14 years AOR = 0.34, AOR = 0.05; 14–15 years AOR = 0.52, AOR = 0.20; 16–17 years AOR = 0.71, AOR = 0.48).

Conclusion

Primary education is likely insufficient to reduce girl child marriage in South Asia, outside of India. Secondary education may be a better protective strategy against this practice for the region, but may be less effective for prevention of marriage among older relative to younger adolescents.  相似文献   
102.
Age-related differences in the thermoregulatory response to morphine have been shown in rats. To determine if these age-related differences would be reflected in the acquisition of tolerance, we studied morphine tolerance induced by either a single morphine dose or implantation of a morphine pellet. precipitated withdrawal was also analyzed by inducing withdrawal with naloxone in morphine-pelleted rats. Senescent (26 or 27 month old), mature (10 or 11 month old) and young (3 or 4 month old) male Fischer 344 rats were restrained and changes in rectal temperature were monitored for six hours after morphine administration. Only mature and young rats exhibited increased hyperthermic responses to a second low dose of morphine (5 mg/kg s.c.). Only young rats became tolerant after a single higher morphine dose (25 mg/kg s.c.). All age groups showed tolerance three days after morphine pellet implantation. Hypothermia was equivalent in all age groups when withdrawal was induced by naloxone in morphine-pelleted rats. These results indicate that older rats were more resistant to the acquisition of tolerance to the thermic effects of morphine; however; with continued morphine treatment, rats became tolerant regardless of age.  相似文献   
103.
Internal eliminated sequences (IESs) often interrupt ciliate genes in the silent germline nucleus but are exactly excised and eliminated from the developing somatic nucleus from which genes are then expressed. Some long IESs are transposons, supporting the hypothesis that short IESs are ancient transposon relics. In light of that hypothesis and to explore the evolutionary history of a collection of IESs, we have compared various alleles of a particular locus (the 81 locus) of the ciliated protozoa Oxytricha trifallax and O. fallax. Three short IESs that interrupt two genes of the locus are found in alleles from both species, and thus must be relatively ancient, consistent with the hypothesis that short IESs are transposon relics. In contrast, TBE1 transposon interruptions of the locus are allele-specific and probably the results of recent transpositions. These IESs (and the TBE1s) are precisely excised from the DNA of the developing somatic macronucleus. Each IES interrupts a highly conserved sequence. A few nucleotides at the ends of each IES are also conserved, suggesting that they interact critically with IES excision machinery. However, most IES nucleotide positions have evolved at high rates, showing little or no selective constraint for function. Nonetheless, the length of each IES has been maintained (+/- 3 bp). While one IES is approximately 33 bp long, three other IESs have very similar sizes, approximately 70 bp long. Two IESs are surrounded by direct repeats of the sequence TTCTT. No other sequence similarities were found between any of the four IESs. However, the ends of one IES do match the inverted terminal repeat consensus sequence of the "TA" IESs of Paramecium. Three O. trifallax alleles appear to have been recipients in recent conversion events that could have been provoked by double-strand breaks associated with IES ends subsequent to IES transposition. Our findings support the hypothesis that short IESs evolved from ancient transposons that have lost most of their sequences, except those necessary for precise excision during macronuclear development.   相似文献   
104.
105.
106.
(1) The effects of thiamine deficiency as produced by pyrithiamine injections have been studied in the weanling mouse. Selected metabolites were measured in extracts from brain and liver of quick-frozen animals. Pyruvate and α-oxoglutarate dehydrogenases and transketolase were also measured. (2) In deficient brain, pyruvate and α-oxoglutarate levels were greatly increased. Xylulose-5-P and 6-P-gluconate were more than doubled. Lactate, glucose-6-P, glucose and P-creatine were moderately elevated, and ATP was increased a little. Glutamate was depressed. (3) In deficient liver, α-oxoglutarate was much increased and ATP was twice normal. Glycogen, glucose, glucose-6-P, 6-P-gluconate, pyruvate, and glutamate were not different from the controls. Lactate was depressed. (4) Pyruvate dehydrogenase activity was reduced to 25 per cent or less in brain and liver. Transketolase and α-oxoglutarate dehydrogenase activities were reduced to 50 per cent in both organs. (5) Thiamine treatment, within 5 hr, largely reversed the metabolite changes brought on by pyrithiamine in brain. At the same time pyruvate and α-oxoglutarate dehydrogenase activities were increased 60 per cent or more in both brain and liver. Transketolase activity in liver was only increased 20 per cent at this time, however, and in brain was unchanged. (6) The results are interpreted to indicate that inhibition of pyruvate and α-oxoglutarate dehydrogenases in brain is sufficient to depress in vivo function. The same seems true for the inhibition of α-oxoglutarate dehydrogenase in liver. However, the changes seen in brain 6-P-gluconate and xyluIose-5-P probably depend on factors other than, or in addition to, the decrease in transketolase activity. It seems worthy of emphasis that in spite of the partial metabolic blocks high-energy phosphate stores were actually increased.  相似文献   
107.
108.
Dothistroma septosporum is the causal agent of Dothistroma needle blight of pine trees. A novel green fluorescent protein (GFP)-based screening method was developed to assess the potential of microorganisms for biocontrol of Dothistroma. The screen utilizes GFP expression as an indicator of metabolic activity in the pathogen and hygromycin resistance selection to determine if the interaction is fungistatic or fungicidal. Results suggested that six of eight Trichoderma isolates tested have the potential to control Dothistroma in vitro, via a fungicidal action. Because D. septosporum produces a broad-spectrum toxin, dothistromin, the inhibition of Trichoderma spp. by D. septosporum was determined by growth rate measurements compared to controls. Inhibition of the Trichoderma spp. ranged from no inhibition to 30% inhibition and was influenced by the assay medium used. The GFP screening method was also assessed to determine if it was suitable for screening bacteria as potential biocontrol candidates. Although a method involving indirect-contact had to be used, two of four Bacillus strains showed antagonistic activity against D. septosporum in vitro, via a fungistatic interaction. The four bacterial strains inhibited D. septosporum growth by 14.0 to 39.8%. This GFP-based method represents a novel approach to screening fungi and bacteria for antagonistic activity.  相似文献   
109.
Abstract

The Open Bay Island skink (Oligosoma taumakae) is one of New Zealand's rarest lizard species. Until 2010, it was known only from two small islands in the Open Bay Island Group, a Māori-owned wildlife sanctuary in South Westland, New Zealand. Skinks on these islands are threatened by predation from weka (Gallirallus australis), a flightless native rail thought to have been introduced to the Open Bay Islands c. 100 years ago. Here, we describe the discovery of Open Bay Island skinks on two vegetated rock stacks located off the coast of Barn Bay, 52 km southwest of the Open Bay Islands. Although small (c. 0.10 and 0.36 ha), the Barn Islands appear to be predator-free, providing an important sanctuary for the skinks. We recommend: (1) a survey of mainland sites with suitable habitat; and (2) an evaluation of the need for island biosecurity measures for detecting and responding to incursions of small mammals.  相似文献   
110.
Yi  D; Lee  RT; Longo  P; Boger  ET; Lee  YC; Petri  WA  Jr; Schnaar  RL 《Glycobiology》1998,8(10):1037-1043
Both the Entamoeba histolytica lectin, a virulence factor for the causative agent of amebiasis, and the mammalian hepatic lectin bind to N-acetylgalactosamine (GalNAc) and galactose (Gal) nonreducing termini on oligosaccharides, with preference for GalNAc. Polyvalent GalNAc- derivatized neoglycoproteins have >1000-fold enhanced binding affinity for both lectins (Adler,P., Wood,S.J., Lee,Y.C., Lee,R.T., Petri,W.A.,Jr. and Schnaar,R.L.,1995, J. Biol. Chem ., 270, 5164-5171). Substructural specificity studies revealed that the 3-OH and 4-OH groups of GalNAc were required for binding to both lectins, whereas only the E.histolytica lectin required the 6-OH group. Whereas GalNAc binds with 4-fold lower affinity to the E.histolytica lectin than to the mammalian hepatic lectin, galactosamine and N-benzoyl galactosamine bind with higher affinity to the E. histolytica lectin. Therefore, a synthetic scheme for converting polyamine carriers to poly-N-acyl galactosamine derivatives (linked through the galactosamine primary amino group) was developed to test whether such ligands would bind the E.histolytica lectin with high specificity and high affinity. Contrary to expectations, polyvalent derivatives including GalN6lys5, GalN4desmosine, GalN4StarburstTMdendrimer, and GalN8StarburstTMdendrimer demonstrated highly enhanced binding to the mammalian hepatic lectin but little or no enhancement of binding to the E.histolytica lectin. We propose that the mammalian hepatic lectin binds with greatest affinity to GalNAc "miniclusters," which mimic branched termini of N-linked oligosaccharides, whereas the E.histolytica lectin binds most effectively to "maxiclusters," which may mimic more widely spaced GalNAc residues on intestinal mucins.   相似文献   
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