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991.
The perspectives of mothers-in-law about intra-household decision-making, family size and family planning are investigated, and their views compared with those of their sons and daughters-in-law. Women (717 daughters-in-law), their husbands (717 sons) and their 522 mothers-in-law were interviewed in eight squatter settlements in Karachi, Pakistan. Decisions about the schooling and health care of children, and the purchase of jewellery, are perceived to lie within the nuclear family domain (i.e. husband and wife). There was a difference in mothers-in-law's, daughters-in-law's and sons' desire to have more children. Twenty-eight per cent of mothers-in-law versus 58%, of daughters-in-law did not want more grandsons/sons and 36%, of mothers-in-law versus 66% of daughters-in-law did not want more granddaughters/daughters. The difference was markedly greater among the mother-in-law/daughter-in-law pairs than in the mother/son pairs. Overall, the mother-in-law's role seems to be somewhat overshadowed by that of her son (family male member), except for limiting family size. It is suggested that mothers-in-law should be included in Information-Education-Communication (IEC) campaigns about family planning. 相似文献
992.
3-O-Mesyl-1,6-di-O-trityl-beta-D-fructofuranosyl-(2-->1)-6-O-trityl-alpha-D-glucopyranoside (3) was synthesized via stannylation of 6,1',6'-tri-O-tritylsucrose with dibutyltin oxide in benzene, followed by treatment of the crude product with methanesulfonyl chloride in the presence of triethylamine in dichloromethane at 0 degrees C. A similar treatment of the tri-tritylsucrose in toluene, instead of benzene, yielded 4-O-mesyl-1,6-di-O-trityl-beta-D-fructofuranosyl-(2-->1)-6-O-trityl-alpha-D-glucopyranoside (4) as the major product. The X-ray crystal structure of the corresponding acetyl derivative, 3-O-acetyl-4-O-mesyl-1,6-di-O-trityl-beta-D-fructofuranosyl-(2-->1)-2,3,4-tri-O-acetyl-6-O-trityl-alpha-D-glucopyranoside (5), confirms the position and stereochemistry of the methanesulfonyl group at C-4 of the fructofuranosyl ring. 相似文献
993.
Milestones in chloroplast genetic engineering: an environmentally friendly era in biotechnology 总被引:17,自引:0,他引:17
Chloroplast genomes defied the laws of Mendelian inheritance at the dawn of plant genetics, and continue to defy the mainstream approach to biotechnology, leading the field in an environmentally friendly direction. Recent success in engineering the chloroplast genome for resistance to herbicides, insects, disease and drought, and for production of biopharmaceuticals, has opened the door to a new era in biotechnology. The successful engineering of tomato chromoplasts for high-level transgene expression in fruits, coupled to hyper-expression of vaccine antigens, and the use of plant-derived antibiotic-free selectable markers, augur well for oral delivery of edible vaccines and biopharmaceuticals that are currently beyond the reach of those who need them most. 相似文献
994.
The Constitutive Heat Shock Protein-70 Is Required for Optimal Expression of Myelin Basic Protein During Differentiation of Oligodendrocytes 总被引:1,自引:0,他引:1
To further elucidate the role of the constitutive heat shock protein-70 (HSC70) as a chaperone for the synthesis of myelin basic protein (MBP), HSC70 content was decreased in oligodendrocyte precursor cells prior to MBP expression either by transfection with an antisense oligonucleotide specific for HSC70, or by exposure to low levels of quercetin, a bioflavonoid known to decrease synthesis of HSC70. As these cells underwent differentiation in vitro, antisense treatment decreased HSC70 levels to 66% of controls. At the same time, a sharp induction resulted in the stress-inducible heat shock protein-70 (HSP70). Levels of two other stress proteins increased as well, namely, the 25-kDa heat shock protein (HSP25) and the 78-kDa glucose regulated protein (GRP78). MBP synthesis proceeded over a normal time course, but at only 50% of control values. As HSC70 content returned to normal, MBP synthesis was also restored to normal levels. Quercetin reduced the expression of HSC70 to an even greater extent than transfection, and prevented the induction of HSP70. In contrast to antisense-treated cells, MBP synthesis was essentially blocked in quercetin-treated cells even though levels of HSP25 and GRP78 increased. Taken together, these observations (a) indicate that HSP70 partially compensates for decreased chaperoning of nascent MBP by HSC70 (HSC70 and HSP70 are closely related and perform similar functions); (b) preclude the involvement of HSP25 and GRP78 in MBP synthesis; and (c) emphasize the requirement of HSC70 for optimal synthesis of MBP. 相似文献
995.
Arbuscular Mycorrhizal Fungi Enhance Zinc and Nickel Uptake from Contaminated Soil by Soybean and Lentil 总被引:1,自引:0,他引:1
Atif Jamal Najma Ayub Muhammad Usman Dr. Abdul G. Khan 《International journal of phytoremediation》2002,4(3):205-221
Generally, soils in Pakistan are deficient in P and N. Due to intensive cropping and irrigation, Pakistani soils have also become deficient in micronutrients such as Zn, Fe, Cu, and Mn. Arbuscular mycorrhizal fungi, which form symbiotic associations with roots of most land plants, are known to enhance uptake of P and trace elements such as Cu, Ni, Pb, and Zn. The present study was conducted to investigate the role of arbuscular mycorrhizae (AM) in uptake of nickel (Ni) and zinc (Zn) by crops viz. soybean (Glycine max (L.) Merrill) and lentil (Lens culinaris Medic). Zn and Ni were applied as ZnSO4 7H2O and NiCl2 respectively, in four concentrations (0.0, 1.0, 3.0, and 5.0 g kg-1 soil). AM inoculum consisted of sand containing sporocarps, spores, and AMF infected root pieces from a pot culture of Glomus mosseae. Control plants received pot culture filtrate containing soil microflora minus AM fungal propagules. A significant difference (p < 0.05) was observed in the dry weights of roots and shoots of the mycorrhizal (M) and nonmycorrhizal (NM) cereal plants. The sievate-amended treatments did not stimulate plant growth to the same extent as the AM fungal amended treatments. Trace metals inhibited the extent of mycorrhizal colonization of the cereal roots. The concentrations of the trace metals in the plant tissues of 12-week old cereal plants were found significantly (p < 0.05) higher in M than NM plants. These results indicate that mycorrhize can be used as effective tools to supply sufficient Zn in generally Zn-deficient Pakistani soils and to ameliorate the toxicity of trace metals in polluted soils. The contents of Ni in mycorrhizal soybean plant tissues were higher than those in the mycorrhizal lentil plant tissues. The implications of these results in mycorrhizo remediation of agricultural soils are discussed. 相似文献
996.
A High Through-put Procedure for Capturing Microsatellites from Complex Plant Genomes 总被引:4,自引:0,他引:4
Connell James P. Pammi Sujata Iqbal Muhammad J. Huizinga Tim Reddy Avutu S. 《Plant Molecular Biology Reporter》1998,16(4):341-349
A method is outlined for large-scale isolation and characterization of microsatellite sequences from complex plant genomes. The method presented here differs from the previously published procedures in the use of randomly sheared (nebulized) genomic DNA for adapter-ligation, rigorous removal of biotinylated oligos, and high-density colony blots for constructing enriched libraries. Using this method we have constructed cotton microsatellite enriched libraries with over 20% (high stringency screening) or 75% (by random sequencing). Thus far we have identified and sequenced over 500 cotton microsatellites using this procedure. The procedure can be used to generate enriched SSR libraries from genomic DNA in about one week. High throughput screening and automated DNA sequencing can be accomplished in less than one month. 相似文献
997.
998.
999.
Deng Chen Muhammad Kamran Shen Chen Junjie Xing Zhiguang Qu Caiyun Liu Zhiyong Ren Xuan Cai Xiao-Lin Chen Jingbo Xu 《Molecular Plant Pathology》2023,24(4):374-390
Cell wall polysaccharides play key roles in fungal development, virulence, and resistance to the plant immune system, and are synthesized from many nucleotide sugars in the endoplasmic reticulum (ER)-Golgi secretory system. Nucleotide sugar transporters (NSTs) are responsible for transporting cytosolic-derived nucleotide sugars to the ER lumen for processing, but their roles in plant-pathogenic fungi remain to be revealed. Here, we identified two important NSTs, NST1 and NST2, in the rice blast fungus Magnaporthe oryzae. Both NSTs were localized in the ER, which was consistent with a function in transporting nucleotide sugar for processing in the ER. Sugar transport property analysis suggested that NST1 is involved in transportation of mannose and glucose, while NST2 is only responsible for mannose transportation. Accordingly, deletion of NSTs resulted in a significant decrease in corresponding soluble saccharides abundance and defect in sugar utilization. Moreover, both NSTs played important roles in cell wall integrity, were involved in asexual development, and were required for full virulence. The NST mutants exhibited decreasing external glycoproteins and exposure of inner chitin, which resulted in activation of the host defence response. Altogether, our results revealed that two sugar transporters are required for fungal cell wall polysaccharides accumulation and full virulence of M. oryzae. 相似文献
1000.
Jameel M. Al-Khayri Salha M. Alshamrani Adel A. Rezk Wael F. Shehata Mustafa I. Almaghasla Tarek A. Shalaby Ahmed M. Saad Fatmah A. Safhi Muhammad N. Sattar Arafat A. Abdel Latef Mahmoud Z. Sitohy Abdallah A. Hassanin 《Phyton》2023,92(5):1493-1512
Appropriate knowledge of the parental cultivars is a pre-requisite for a successful breeding program. This study
characterized fruit yield, quality attributes, and molecular variations of ten tomato cultivars during three consecutive generations under greenhouse conditions. Peto 86, Castle Rock, and Red Star cultivars showed the highest
fruit yield (kg/plant), total phenolic compounds (TPC), and sap acidity. Principal component analysis categorized
the evaluated fruit yield into three groups based on their quality attributes. A robust positive correlation appeared
among traits inside each group. A positive correlation was likewise noticed between the first and the second
groups. However, a negative correlation was detected between the first, the second and the third group. Molecular
profiling, using seven inter-simple sequence repeat (ISSR) primers, produced 60 loci, including 49 polymorphic
loci. The molecular analysis also pinpointed the highest genetic similarity (0.92) between P73 and Moneymaker,
while the lowest genetic similarity (0.46) was observed between Castle Rock and Moneymaker. The cultivars
P73 and Moneymaker showed the lowest genetic distance (2.24), while the highest genetic distance (5.92) was
observed between Super Marmand and Peto86, on the one hand, and between Castle Rock and Moneymaker,
on the other hand. The chemical analysis of fruit sap indicated the highest levels of TPC, total flavonoids, anthocyanin, ascorbic acid and total soluble solids in Peto 86 and Castle Rock cultivars. Phylogeny analysis of tomato
cultivars based on morphological and molecular attributes indicated four distinct clades. Peto 86, Castle Rock, and Red star cultivars can be recommended for the tomato hybridization breeding programs in the future, with other
tomato cultivars as potentially high-yielding parents. 相似文献