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1.
Summary This paper reports that the opaque-6 (o6) mutation of maize, which causes seedling lethality and interferes in the endosperm with the synthesis of zeins and b-32 protein, is a proline requiring mutant functionally allelic to proline-1 (pro-1). Furthermore, immunological studies on the b-32 content of ten independently originated o6 and pro-1 alleles demonstrated that four alleles contain an apparently normal b-32 protein while the others are either devoid of it or contain trace amounts of cross-reacting proteins of lower molecular weight.  相似文献   
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Noninvasive ambulatory blood pressure (BP) monitoring is a developing method in clinical practice. Its interpretation needs reference standards stratified by age and gender. This study addresses ambulatory BP monitoring in elderly people with the purpose of quantifying the discrete and periodic variability of BP pattern over a 24-h period. The ABPM was performed in 92 clinically healthy subjects (45 men and 47 women) ranging in age from 76 to 102 years. The results refer to the time-qualified mean values with their dispersion, to the circadian rhythm with its parameters, and to the daily baric impact (BI) with its variability. The conclusion is drawn that BP preserves its nychtohemeral variability and circadian rhythmicity despite old age. The daily BP mean level and BI in older people in good health are comparable with those of young subjects, suggesting that humans surviving into old age are characterized by a eugenic control of their pressure regimen.  相似文献   
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The synthesis and deposition of seed storage proteins in maize are affected by several dominant and recessive mutants. The effect of three independent mutations, floury-2 (fl2), Defective endosperm-B30 (De-B30), and Mucronate (Mc), that reduce zein level in the endosperm were investigated. These mutations also control the level of b-70, a polypeptide bound to protein bodies, which is separable into the two isoforms b-70I and b-70II by two-dimensional gel electrophoresis. Both isoforms are overexpressed 10-fold in fl2; however, only b-70I is present in De-B30 and Mc, which contain an amount of total b-70 isoforms fivefold higher than in the wild type. Both b-70I and b-70II resemble heat shock protein (HSP70) in that they bind ATP, cross-react with anti-HSP antibodies, and have N-terminal sequence homology to HSP70. All maize protein body-located b-70 characteristics are typical of those of chaperone-like HSPs. A third protein, b-70III, similar in size to but slightly more acidic than b-70I and b-70II, also binds ATP and reacts with the same antibody, providing evidence for the presence in endosperm extracts of a cytosolic chaperone-like protein. The level of b-70III was not altered by the mutations studied. The results suggested that the repression effect of the three mutations on zein accumulation may be mediated by the alteration of a zein transport or zein assembly process involving b-70I and b-70II.  相似文献   
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Zein is the major storage protein of the endosperm of maize kernels. When this alcohol-soluble protein is subjected to SDS polyacrylamide gel electrophoresis, it is resolved into four fractions of different molecular weight: 10, 14, 20 and 22 kilodaltons (kd). Each fraction is heterogeneous with respect to isoelectric pH. For example, the 20 kd fraction contains at least seven subfractions as revealed by isoelectric focusing in polyacrylamide gels. In this report, we present evidence that the structural genes coding for the 20 kd proteins are clustered on the short arm of chromosome 7, a region that also bears loci regulating endosperm zein biosynthesis [opaque-2 (02) and defective endosperm-B30 (De*-B30)]. The organization of these zein genes suggests that the evolution of at least some of the maize genome has occurred as the result of repeated duplication and divergence of chromosome segments.  相似文献   
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Nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas allows the deposition of metal oxides with tunable morphology, structure, density and stoichiometry by a proper control of the plasma plume expansion dynamics. Such versatility can be exploited to produce nanostructured films from compact and dense to nanoporous characterized by a hierarchical assembly of nano-sized clusters. In particular we describe the detailed methodology to fabricate two types of Al-doped ZnO (AZO) films as transparent electrodes in photovoltaic devices: 1) at low O2 pressure, compact films with electrical conductivity and optical transparency close to the state of the art transparent conducting oxides (TCO) can be deposited at room temperature, to be compatible with thermally sensitive materials such as polymers used in organic photovoltaics (OPVs); 2) highly light scattering hierarchical structures resembling a forest of nano-trees are produced at higher pressures. Such structures show high Haze factor (>80%) and may be exploited to enhance the light trapping capability. The method here described for AZO films can be applied to other metal oxides relevant for technological applications such as TiO2, Al2O3, WO3 and Ag4O4.  相似文献   
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Grain protein content (GPC) is an important quality factor in both durum and bread wheats. GPC is considered to be a polygenic trait influenced by environmental factors and management practice. The objectives of this study were both to compare the quantitative trait loci (QTL) for GPC in a population of 65 recombinant inbred lines of tetraploid wheats evaluated in three locations for several years (eight data sets), and to investigate the genetic relationship among GPC and grain yield. QTLs were determined based on the Messapia × dicoccoides linkage map which covers 217 linked loci on the 14 chromosomes with 42 additional loci as yet unassigned to linkage groups. The map extends to 1352 cM; the average distance between adjacent markers was 6.3 cM. Seven QTLs for GPC, located on the chromosome arms 4BS, 5AL, 6AS (two loci), 6BS, 7AS and 7BS, were detected that were significant in at least one environment at P<0.001 or in at least two environments at P<0.01. One QTL was significant in all but one environment, two were significant in four or five environments, and four were significant in two out of eight environments. Six out of seven protein content QTLs had pleiotropic effects or were associated to QTLs for grain yield and explained the negative correlation among GPC and yield components. The present results support the concept that studies conducted in a single environment are likely to underestimate the number of QTLs that can influence a trait and that the phenotypic data for a quantitative trait should be collected over a range of locations to identify putative QTLs and determine their phenotypic effects.  相似文献   
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Giardia duodenalis is a well recognised enteropathogen, while Dientamoeba fragilis is rarely detected and consequently it is not recognised as an important human pathogen. In 2002-2003, a survey has been carried out on enteroparasites in faecal samples of outpatients attending a day care centre in the town of Perugia (Central Italy). To improve the detection level, at least three samples from each patient were collected at different days and within two hours from defecation. The coproparasitological examination has been carried out by direct microscopic examination, faecal concentration, and Giemsa and modified Ziehl-Nielsen stainings of faecal smears. The genotypes of Giardia duodenalis isolates were determined by PCR of the beta-giardin gene. Of 1,989 enrolled people (966 children, 1,023 adults), 165 persons (8.3%; 153 adults, 15.0%; 12 children, 1.2%), were positive for parasites, but only 1 12 adults (73.2% of those infected) and eight children (66.7% of those infected) harboured D. fragilis and G. duodenalis. Both the Assemblages A and B were detected in 18 G. duodenalis isolates examined at the beta-giardin gene. The higher prevalence of D. fragilis infections than that of G. duodenalis is probably related to the method used, a procedure, which is rarely followed in laboratories for the diagnosis of enteric parasites. These epidemiological data suggest that when faecal samples are examined after a period of time and without Giemsa staining, most D. fragilis infections goes undetected.  相似文献   
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Renal cell carcinoma (RCC) tissue is composed of a mixture of neoplastic and normal cells, which complicate proteome analysis. The aim of our study was to investigate whether it is feasible to establish primary cell cultures of RCC and of renal cortex maintaining the tissue phenotype along with a more homogeneous and enriched cytological material. Fourteen (82.3%) primary cultures from 17 surgical cases were established and characterized by morphology, growth rate, immunocytochemistry, and molecular analysis performed by Real-time PCR, Western blotting, two-dimensional electrophoresis (2-DE), and mass spectrometry. Cultures showed >90% cytokeratine-positive epithelial cells. In primary tumor cultures, the molecular phenotype of manganese superoxide dismutase and heat shock protein 27 was the same as that found in tumor tissues with overexpression and increased number of isoforms. Moreover, 27 out 28 specific proteins and their isoforms, present in spots excised from 2-DE gel of cortex or RCC cultures, corresponded to those identified on the 2-DE tissue cortex reference map, suggesting that these primary cultures retain the proteomic profile of the corresponding tissues.  相似文献   
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