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51.
Molecular and Cellular Biochemistry - Pregnancy evokes many challenges on the maternal cardiovascular system that may unmask predispositions for future disease. This is particularly evident for...  相似文献   
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An efficient method for release of ferulic acid from sweet potato stems was developed. Ferulic acid along with phenolic compounds were released from stems by acid and alkaline treatments. The base hydrolysis with 0.1 N NaOH yielded the highest quantity of total extracts (471.1 mg/g). The stems released more phenolic compounds when 0.0125∼0.025 N NaOH was employed. Where as ferulic acid release was maximal with 0.05 N H2SO4 (0.32 mg/g). Ferulic acid was separated from phenolics by column chromatography. Among the elution solvents, ethyl acetate fractions (80%) contained ferulic acid. Ethyl acetate eluants were further fractionated with n-hexane/ethyl acetate/formic acid (100/50/0.5, v/v/v). All fractions showed ferulic acid and phenolic compounds. Fraction V among them was ascribed to ferulic acid with an yield of 5.41 mg/g of dry sweet potato tissue.  相似文献   
53.
Evaluations of genetic diversity in domestic livestock populations are necessary to implement region‐specific conservation measures. We determined the genetic diversity and evolutionary relationships among eight geographically and phenotypically diverse cattle breeds indigenous to west‐central India by genotyping these animals for 22 microsatellite loci. A total of 326 alleles were detected, and the expected heterozygosity ranged from 0.614 (Kenkatha) to 0.701 (Dangi). The mean number of alleles among the cattle breeds ranged from 7.182 (Khillar) to 9.409 (Gaolao). There were abundant genetic variations displayed within breeds, and the genetic differentiation was also high between the Indian cattle breeds, which displayed 15.9% of the total genetic differentiation among the different breeds. The genetic differentiation (pairwise FST) among the eight Indian breeds varied from 0.0126 for the Kankrej–Malvi pair to 0.2667 for Khillar–Kenkatha pair. The phylogeny, principal components analysis, and structure analysis further supported close grouping of Kankrej, Malvi, Nimari and Gir; Gaolao and Kenkatha, whereas Dangi and Khillar remained at distance from other breeds.  相似文献   
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Fetal growth restriction (FGR) and coagulopathies are often associated with aberrant maternal inflammation. Moderate-intensity exercise during pregnancy has been shown to increase utero-placental blood flow and to enhance fetal nutrition as well as fetal and placental growth. Furthermore, exercise is known to reduce inflammation. To evaluate the effect of moderate-intensity exercise on inflammation associated with the development of maternal coagulopathies and FGR, Wistar rats were subjected to an exercise regime before and during pregnancy. To model inflammation-induced FGR, pregnant rats were administered daily intraperitoneal injections of E. coli lipopolysaccharide (LPS) on gestational days (GD) 13.5–16.5 and sacrificed at GD 17.5. Control rats were injected with saline. Maternal hemostasis was assessed by thromboelastography. Moderate-intensity exercise prevented LPS-mediated increases in white blood cell counts measured on GD 17.5 and improved maternal hemostasis profiles. Importantly, our data reveal that exercise prevented LPS-induced FGR. Moderate-intensity exercise initiated before and maintained during pregnancy may decrease the severity of maternal and perinatal complications associated with abnormal maternal inflammation.  相似文献   
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A halopalkaliphilic marine Saccharopolyspora sp. stain A9 with an ability to produce surfactants, oxidant and detergent stable α-amylase was isolated from marine sediments collected from west coast of India. The α-amylase from strain A9 was purified to homogeneity with the aid of ammonium sulfate precipitation and gel filtration chromatography by using Sephadex G-75, insoluble corn starch and sephacryl S-100 column, with a 39.01-fold increase in specific activity. SDS-PAGE and zymogram activity staining showed a single band equal to molecular mass of 66 kDa. Enzyme was found to be stable in presence of wide range of NaCl concentration with maximum activity found at 11% (w/v) of NaCl. Enzyme showed remarkable stability towards laboratory surfactants, detergents and oxidants. Glucose, maltose and maltotriose were the main end product of starch hydrolysis, indicating it is α-amylase.  相似文献   
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Summary In wild-type Scopolia parvilfora (Solanaceae) tissues, only the roots express the enzyme putrescine N-methyltransferase (PMT; EC 2.1.1.53), which is the first specific precursor of the tropane alkaloids. Moreover, the tropanane alkaloid levels were the highest in the root (0.9 mg g−1 on a dry weight basis), followed by the stem and then the leaves. We metabolically engineered S. parviflora by introducing the tobacco pmt gene into its genome by a binary vector system that employs disarmed Agrobacterium rhizogenes. The kanamycin-resistant hairy root lines were shown to bear the pmt gene and to overexpress its mRNA and protein product by at least two-fold, as determined by polymerase chain reaction (PCR) and Northern and Western blottings, respectively. The transgenic lines also showed higher PMT activity and were morphologically aberrant in terms of slower growth and the production of lateral roots. The overexpression of pmt markedly elevated the scopolamine and hyoscyamine levels in the transgenic lines that showed the highest pmt mRNA and PMT protein levels. Thus, overexpression of the upstream regulator of the tropane alkaloid pathway enhanced the biosynthesis of the final product. These observations may be useful in establishing root culture systems that generate large yields of tropane alkaloids. These authors contributed equally to this paper (co-first authors).  相似文献   
58.
Plant Cell, Tissue and Organ Culture (PCTOC) - Static magnetic field (SMF) as a priming method (magnetopriming) is used to invigorate plant growth and development culminating in improved...  相似文献   
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Objective

To examine the effect of peer support on duration of exclusive breastfeeding (EBF) in low and middle-income countries (LMICs).

Data Sources

Medline, EMBASE, and Cochrane Central Register for Controlled Trials were searched from inception to April 2012.

Methods

Two authors independently searched, reviewed, and assessed the quality of randomized controlled trials utilizing peer support in LMICs. Meta-analysis and metaregression techniques were used to produce pooled relative risks and investigate sources of heterogeneity in the estimates.

Results

Eleven randomized controlled trials conducted at 13 study sites met the inclusion criteria for systematic review. We noted significant differences in study populations, peer counselor training methods, peer visit schedule, and outcome ascertainment methods. Peer support significantly decreased the risk of discontinuing EBF as compared to control (RR: 0.71; 95% CI: 0.61–0.82; I2 = 92%). The effect of peer support was significantly reduced in settings with >10% community prevalence of formula feeding as compared to settings with <10% prevalence (p = 0.048). There was no evidence of effect modification by inclusion of low birth weight infants (p = 0.367) and no difference in the effect of peer support on EBF at 4 versus 6 months postpartum (p = 0.398).

Conclusions

Peer support increases the duration of EBF in LMICs; however, the effect appears to be reduced in formula feeding cultures. Future studies are needed to determine the optimal timing of peer visits, how to best integrate peer support into packaged intervention strategies, and the effectiveness of supplemental interventions to peer support in formula feeding cultures.  相似文献   
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