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111.
A spectrophotometric assay is proposed to determine the levels of aspartate aminotransferase (AAT) isoenzymes from chicken liver by a steady-state kinetic method which depends on the differential inhibition of these isoenzyme forms by high concentrations of substrate 2-oxoglutarate at pH 6.2. The use of a standard curve permits the determination of the percentage of chicken liver c-AAT and m-AAT isoenzymes. This method yields results in good correlation with those achieved by different extent adipate inhibition and by differential centrifugation.  相似文献   
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Background

Heart valve surgery outcomes are unknown in middle-income countries and thus cannot be used in health system decision making processes. This study estimated in-hospital mortality and medium and long-term survival.

Methods

This was a retrospective study of 78,806 patients who underwent heart valve surgery between 2001 and 2007 in Brazil. Two national databases were used, the Hospital Information System and the Mortality Information System. Kaplan-Meier survival analysis and log-rank tests were performed. Maximum and median follow-up was 7.7 and 2.8 years, respectively (0.002–7.707).

Results

Valve replacement accounted for 69.1% of procedures performed. Mitral stenosis, the most common valve injury, represented 38.9% of the total. In 94.7% of mitral stenosis patients, aetiology was rheumatic heart disease. In-hospital mortality was 7.6% and was higher for women, for patients who had undergone concomitant coronary artery bypass grafting (CABG) and for the elderly. Overall survival was 69.9% at the end of follow-up. Survival was worst among elderly, male and concomitant CABG patients (P<0.001).

Conclusions

Rheumatic heart disease is still a major public health problem in Brazil. In-hospital mortality and global survival rates of patients who have undergone heart valve surgery were less satisfactory than those reported in high-income countries. The findings of this study can contribute to guiding decision making processes in middle-income countries similar to Brazil and others concerned with improving the quality of care.
  相似文献   
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Advances in plant breeding through marker-assisted selection (MAS) are only possible when genes or quantitative trait loci (QTLs) can contribute to the improvement of elite germplasm. A population of recombinant inbred lines (RILs) was developed for one of the best crosses of the Spanish National Barley Breeding Program, between two six-row winter barley cultivars Orria and Plaisant. The objective of this study was to identify favourable QTLs for agronomic traits in this population, which may help to optimise breeding strategies for these and other elite materials for the Mediterranean region. A genetic linkage map was developed for 217 RILs, using 382 single nucleotide polymorphism markers, selected from the barley oligonucleotide pool assay BOPA1 and two genes. A subset of 112 RILs was evaluated for several agronomic traits over a period of 2 years at three locations, Lleida and Zaragoza (Spain) and Fiorenzuola d’Arda (Italy), for a total of five field trials. An important segregation distortion occurred during population development in the region surrounding the VrnH1 locus. A QTL for grain yield and length of growth cycle was also found at this locus, apparently linked to a differential response of the VrnH1 alleles to temperature. A total of 33 QTLs was detected, most of them for important breeding targets such as plant height and thousand-grain weight. QTL × environment interactions were prevalent for most of the QTLs detected, although most interactions were of a quantitative nature. Therefore, QTLs suitable for MAS for most traits were identified.  相似文献   
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Conventional Asante gender roles in Ghana emphasize biological motherhood for women, but Asante assume mothers' loyalties and schedule conflicts will interfere with equally female gendered expectations within marriage, not with fulltime paid work. Asante express their maternal devotion most by working tirelessly to meet their children's financial needs, not by staying home with them. In this paper I analyze urban Asante ideals and practices about gender and parenting, drawing on life histories and fieldwork with Kumasi traders since 1978. Market trading is ideal "nursing-mother work" because it generates the steady income needed to raise children successfully to adulthood, not because it is compatible with childcare. Marriage depends directly on women's intimate domestic work, creating structural tension with motherhood. Concepts about motherly fathers, manly women, and fools of both genders show how the distribution of income and capital defines gender and kin role performance. Asante have accommodated historical changes in gender expectations about work, parenihood, and marriage within their general positive emphasis on negotiability and renegoiiability of relationship content, [ gender, work, Asante, traders, parenting ]  相似文献   
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We have recently described how to achieve COX-2 selectivity from the non-selective inhibitor indomethacin (1) using a combination of a pharmacophore and computer 3-D models based on the known X-ray crystal structures of cyclooxygenases. In the present study we have focused on the design of COX-2 selective analogues of the NSAID ketoprofen (2). The design is similarly based on the combined use of the previous pharmacophore together with traditional medicinal chemistry techniques motivated by the comparative modeling of the 3-D structures of 2 docked into the COX active sites. The analysis includes use of the program GRID to detect isoenzyme differences near the active site region and is aimed at suggesting modifications of the basic benzophenone frame of the lead compound 2. The resulting series of compounds bearing this central framework is exemplified by the potent and selective COX-2 inhibitor 17 (LM-1669).  相似文献   
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Insulin production afforded by hepatic gene therapy (HGT) retains promise as a potential treatment for type 1 diabetes, but successful approaches have been limited. We employed a novel and previously untested promoter for this purpose, glucose transporter-2 (GLUT2) to drive insulin production via delivery by recombinant adeno-associated virus (rAAV). In vitro, the GLUT2 promoter was capable of robust glucose-responsive expression in transduced HepG2 human hepatoma cells. Therefore, rAAV constructs were designed to express the furin-cleavable human preproinsulin B10 gene, under the control of the murine GLUT2 promoter and packaged for delivery with rAAV expressing the type 5 capsid. Streptozotocin-induced diabetic mice were subjected to hepatic portal vein injection immediately followed by implantation of a sustained-release insulin pellet to allow time for transgenic expression. All mice injected with the rAAV5-GLUT2-fHPIB10 virus remained euglycemic for up to 35 days post-injection, with 50% euglycemic after 77 days post-injection. In contrast, mock-injected mice became hyperglycemic within 15 days post-injection following dissolution of the insulin pellet. Serum levels of both human insulin and C-peptide further confirmed successful transgenic delivery by the rAAV5-GLUT2-fHPIB10 virus. These findings indicate that the GLUT2 promoter may be a potential candidate for regulating transgenic insulin production for hepatic insulin gene therapy in the treatment of type I diabetes.  相似文献   
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Background

Cross-cultural adaptation is a necessary process to effectively use existing instruments in other cultural and language settings. The process of cross-culturally adapting, including translation, of existing instruments is considered a critical set to establishing a meaningful instrument for use in another setting. Using a multi-step approach is considered best practice in achieving cultural and semantic equivalence of the adapted version. We aimed to ensure the content validity of our instruments in the cultural context of KwaZulu-Natal, South Africa.

Methods

The Iowa Infant Feeding Attitudes Scale, Breastfeeding Self-Efficacy Scale-Short Form and additional items comprise our consolidated instrument, which was cross-culturally adapted utilizing a multi-step approach during August 2012. Cross-cultural adaptation was achieved through steps to maintain content validity and attain semantic equivalence in the target version. Specifically, Lynn’s recommendation to apply an item-level content validity index score was followed. The revised instrument was translated and back-translated. To ensure semantic equivalence, Brislin’s back-translation approach was utilized followed by the committee review to address any discrepancies that emerged from translation.

Results

Our consolidated instrument was adapted to be culturally relevant and translated to yield more reliable and valid results for use in our larger research study to measure infant feeding determinants effectively in our target cultural context.

Conclusions

Undertaking rigorous steps to effectively ensure cross-cultural adaptation increases our confidence that the conclusions we make based on our self-report instrument(s) will be stronger. In this way, our aim to achieve strong cross-cultural adaptation of our consolidated instruments was achieved while also providing a clear framework for other researchers choosing to utilize existing instruments for work in other cultural, geographic and population settings.
  相似文献   
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