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21.
The reaction of compounds 1, 2, 3, 4, or 13 with 2-chloroethyl methyl ether or 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide, afforded some acyclic and cyclic nucleosides of thieno[2,3-d]pyrimidine derivatives. Furthermore, cyclic C-nucleosides 24 and 25 were prepared from the reaction of 20, 21 or from 26, 27 with D-glucose. The antimicrobial evaluation of some prepared products showed promising antimicrobial activity.  相似文献   
22.
There is an important role of understanding the genetic diversity among and within inbred lines at the molecular level for maize improvement in different breeding programs. The present study was devoted to estimate the level of genetic diversity among the inbred lines of maize using the simple sequence repeat analysis (SSR). The application of six different SSR markers successfully provided the information on similarity or diversity as well as the heterozygosity of the allelic loci for all the eight inbred line of maize.  相似文献   
23.
From the fruits of Kigelia pinnata DC., a new furanone derivative formulated as 3-(2'-hydroxyethyl)-5-(2"-hydroxypropyl)-dihydrofuran-2(3H)-one (1), and four new iridoids named; 7-hydroxy viteoid II (2), 7-hydroxy eucommic acid (3), 7-hydroxy-10-deoxyeucommiol (4) and 10-deoxyeucommiol (5) have been isolated together with seven known iridoids, jiofuran (6), jioglutolide (7), 1-dehydroxy-3,4-dihydroaucubigenin (8), des-p-hydroxybenzoyl kisasagenol B (9), ajugol (10), verminoside (11) and 6-trans-caffeoyl ajugol (12). The structures of the isolated compounds were characterized by different spectroscopic methods.  相似文献   
24.
The objective of this review is to clarify aspects of immunological and biochemical adaptations of schistosomes to their intermediate and final mammalian hosts. Adaptations to the mammalian hosts are traced in relation to cercarial penetration of mammalian skin, glucose transport and metabolism. The unusual ability of schistosome surface membrane to escape immune recognition and damage are reviewed. Moreover, the behavioural changes induced in the intermediate hosts by schistosomes are considered. The evolutionary adaptation to molluscan hosts aims to increase the probability of transmission of the parasite into its mammalian host. This review inspires more hope for further design of anti-schistosome drugs through disturbing aspects of biochemical and immunological adaptations in schistosome parasitism.  相似文献   
25.
The alkaloids of Strychnos icaja (Loganiaceae) have been studied. An extract from Zaire leaf material yielded nine alkaloids, comprising novacine, the new base 21,22-α-epoxy-4,14-dihydroxy-3-methoxy-N-methyl-sec.-pseudostrychnine, and seven others of known structure previously obtained from the plant. Cameroun leaf material gave five alkaloids, of which one, 21,22-α-epoxy-3,4-dimethoxy-N-methyl-sec.-pseudostrychnine, is new. Fruits from Gabon afforded eight alkaloids; two of them are new and are formulated as 21,22-α-epoxy-4-methoxy-N-methyl-sec.-pseudostrychnine and the corresponding 14-hydroxy derivative.  相似文献   
26.

Background  

Xenobiotics are neurotoxins that dramatically alter the health of the child. In addition, an inefficient detoxification system leads to oxidative stress, gut dysbiosis, and immune dysfunction. The consensus among physicians who treat autism with a biomedical approach is that those on the spectrum are burdened with oxidative stress and immune problems. In a trial to understand the role of detoxification in the etiology of autism, selected parameters related to sulfur-dependent detoxification mechanisms in plasma of autistic children from Saudi Arabia will be investigated compared to control subjects.  相似文献   
27.

Background

Primary hyperoxaluria type 1 (PH1) is an autosomal recessive inherited metabolic disease, characterized by progressive kidney failure due to renal deposition of calcium oxalate. Mutations in the AGXT gene, encoding the liver-specific enzyme alanine glyoxylate aminotransferase, are responsible for the disease. We aimed to determine the mutational spectrum causing PH1 and to provide an accurate tool for diagnosis as well as for prenatal diagnosis in the affected families.

Methods

Direct sequencing was used to detect mutations in the AGXT gene in DNA samples from 13 patients belonging to 12 Tunisian families.

Results

Molecular analysis revealed five mutations causing PH1 in Tunisia. The mutations were identified along exons 1, 2, 4, 5 and 7. The most predominant mutations were the Maghrebian “p.I244T” and the Arabic “p.G190R”. Furthermore, three other mutations characteristic of different ethnic groups were found in our study population. These results confirm the mutational heterogeneity related to PH1 in Tunisian population. All the mutations are in a homozygous state, reflecting the high impact of endogamy in our population.

Conclusion

Mutation analysis through DNA sequencing can provide a useful first line investigation for PH1. This identification could provide an accurate tool for prenatal diagnosis, genetic counseling and screen for potential presymptomatic individuals.  相似文献   
28.
5-Hydroxymethylcytosine has recently been characterized as the ‘sixth base’ in human DNA. To enable research on this DNA modification, we report an improved method for the synthesis of 5-hydroxymethyl-2′-deoxycytidine (5-HOMedC) phosphoramidite for site-specific incorporation into oligonucleotides. To minimize manipulations we employed a temporary protecting group-free 2′-deoxyuridine to 2′-deoxycytidine conversion procedure that utilizes phase transfer catalysis. The desired 5-HOMedC phosphoramidite is obtained in six steps and 24% overall yield from 2′-deoxyuridine.  相似文献   
29.
ABSTRACT: BACKGROUND: Breast carcinoma is known as a heterogeneous disease because gene expression analyses identify several subtypes and the molecular profiles are prognostic and predictive for patients. Our aim, in this study, is to estimate the prevalence of breast cancer subtypes and to determine the relationship between clinico-pathological characteristics, overall survival (OS) and disease free survival (DFS) for patients coming from north-east of Morocco. METHODS: We reviewed 366 cases of breast cancer diagnosed between January 2007 to June 2010 at the Department of pathology. Age, size tumor, metastatic profile, node involvement profile, OS and DFS were analyzed on 181 patients. These last parameters were estimated by Kaplan-Meier analysis and log-rank test to estimate outcome differences among subgroups. RESULTS: The average age was 45 years, our patients were diagnosed late (57% stage III, 17.5% stage IV) with a high average tumor size. Luminal A subtype was more prevalent (53.6%) associated with favorable clinic-pathological characteristics, followed by luminal B (16.4%), Her2-overexpressing (12.6%), basal-like (12.6%) and unclassified subtype (4.9%).Survival analysis showed a significant difference between subtypes. The triple negative tumors were associated with poor prognosis (49% OS, 39% DFS), whereas the luminal A were associated with a better prognosis (88% OS, 59% DFS). The luminal B and the Her2-overexpressing subtypes were associated with an intermediate prognosis (77% and 75% OS, and 41% and 38% DFS respectively). CONCLUSION: This study showed that molecular classification by immunohistochemistry was necessary for therapeutic decision and prognosis of breast carcinoma. The luminal A subtype was associated with favorable biological characteristics and a better prognosis than triple negative tumors that were associated with a poor prognosis and unfavorable clinic-pathological characteristics.  相似文献   
30.
BackgroundSchools play a key role in supporting the well-being and resettlement of refugee children, and parental engagement with the school may be a critical factor in the process. Many resettlement countries have policies in place to support refugee parents’ engagement with their children’s school. However, the impact of these programs lacks systematic evaluation. This study first aimed to validate self-report measures of parental school engagement developed specifically for the refugee context, and second, to identify parent characteristics associated with school engagement, so as to help tailor support to families most in need.Methods and findingsThe report utilises 2016 baseline data of a cohort study of 233 Arabic-speaking parents (77% response rate) of 10- to 12-year-old schoolchildren from refugee backgrounds across 5 schools in Sydney, Australia. Most participants were born in Iraq (81%) or Syria (11%), and only 25% spoke English well to very well. Participants’ mean age was 40 years old, and 83% were female. Confirmatory factor analyses were run on provisional item sets identified from a literature review and separate qualitative study. The findings informed the development of 4 self-report tools assessing parent engagement with the school and school community, school belonging, and quality of the relationship with the schools’ bilingual cultural broker. Cronbach alpha and Pearson correlations with an established Teacher–Home Communication subscale demonstrated adequate reliability (α = 0.67 to 0.80) and construct and convergent validity of the measures (p < 0.01), respectively.Parent characteristics were entered into respective least absolute shrinkage and selection operator (LASSO) regression analyses. The degree of parents’ psychological distress (as measured by the Kessler10 self-report instrument) and postmigration living difficulties (PLMDs) were each associated with lower school engagement and belonging, whereas less time lived in Australia, lower education levels, and an unemployed status were associated with higher ratings in relationship quality with the schools’ cultural broker. Study limitations include the cross-sectional design and the modest amount of variance (8% to 22%) accounted for by the regression models.ConclusionsThe study offers preliminary refugee-specific measures of parental school engagement. It is expected they will provide a resource for evaluating efforts to support the integration of refugee families into schools. The findings support the need for initiatives that identify and support parents with school-attending children from refugee backgrounds who are experiencing psychological distress or resettlement stressors. At the school level, the findings suggest that cultural brokers may be effective in targeting newly arrived families.

Jess Baker and co-workers study engagement of Arabic-speaking refugees with their children’s schools in Australia.  相似文献   
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